CEMENT , TYPES OF CEMENTS , PORTLAND CEMENT
TYPES OF PORTLAND CEMENT, GENERAL FEATURES OF THE MAIN TYPES OF PORTLAND CEMENT, ORDINARY PORTLAND CEMENT (OPC), RAPID HARDENING PORTLAND CEMENT, SPECIAL TYPES OF RAPID HARDENING PORTLAND CEMENT, MANUFACTURE OF PORTLAND CEMENT, Raw Materials, Crushing & Grinding of Raw Materials,Type of cement processes, Wet Process, Dry process, Burning Process, Grinding, storage, packing, dispatch,CEMENT CHEMISTRY,Chemical Compositions,Bogue’s Equations, Fineness of cement
Manufaturing Process Of Cement
Contents-
What is CEMENT ?
Introduction
Diff. B/w Cement and Portland Cement
Components Of Portland Cement
History of PORTLAND CEMENT.
Manufacturing of PORTLAND CEMENT.
Components
Processes
Dry Process
Wet Process
The document provides information about cement, including its history, chemical composition, manufacturing process, hydration, types of cement and tests conducted on cement. It begins with describing how cement is made from raw materials such as limestone, clay and iron ore through grinding, heating and cooling processes. It then discusses the chemistry and reactions involved in cement hydration. The document also lists and describes common types of cement used in construction, such as ordinary Portland cement, rapid hardening cement, white cement, as well as tests to measure cement consistency, setting time and strength.
Powerpoint presentation on CEMENT {PPT}Prateek Soni
Cement is a mixture of calcareous, siliceous, and argillaceous substances that is used as a binding agent in construction. It is produced through a process involving mixing raw materials, burning in a rotary kiln, and grinding the clinker produced. The manufacturing process can be either dry or wet. Key tests are conducted on cement to check properties like strength, color, presence of lumps, and solubility in water. There are various types of cement suited for different applications.
Cement is produced by heating limestone and clay at high temperatures to form clinker, which is then ground with gypsum. The key compounds formed are tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite. When mixed with water, cement undergoes hydration reactions that cause it to harden over time. Tricalcium silicate reacts rapidly and contributes to early strength, while dicalcium silicate reacts slowly and provides later strength. Tricalcium aluminate also reacts quickly but is retarded by gypsum addition. The reactions are exothermic and generate heat.
The document discusses different types of cement. It defines cement and describes its composition and manufacturing process. The main types discussed are ordinary Portland cement (OPC), Portland pozzolana cement (PPC), Portland blast furnace slag cement (PBSF), rapid hardening cement, low heat cement, sulfate resisting cement, and white cement. It provides details on the characteristics and common applications of each cement type.
Cement is topic;like and give credit for my free work
cement
cement and its types
Manufacturing of cement
uses of cement
wet process
dry process
portland cement
raw materials used in cement
field tests for cement
Cement is produced through a process involving crushing, grinding, and burning of limestone and clay. Joseph Aspdin first produced Portland cement in 1824. The first cement factory in India was established in Tamil Nadu in 1904. Cement production involves quarrying raw materials, crushing them, mixing with water or dry process, grinding, burning at high temperatures to form clinker, cooling clinker, and final grinding with gypsum. Cement is used widely in construction activities like building, roads, bridges due to its binding properties and high compressive strength.
Cement is a binding agent that sets and hardens after mixing with water. Romans first developed hydraulic cement by mixing volcanic ash with lime. Portland cement, the most common type today, was invented in 1824 and consists of calcium silicates and other compounds. It is produced through a process of grinding raw materials like limestone and clay, heating the mixture in a kiln to form clinker, then grinding the clinker with gypsum. The clinker compounds hydrate and harden when mixed with water. Cement is primarily used to bind sand, gravel and water into concrete for construction applications.
Manufaturing Process Of Cement
Contents-
What is CEMENT ?
Introduction
Diff. B/w Cement and Portland Cement
Components Of Portland Cement
History of PORTLAND CEMENT.
Manufacturing of PORTLAND CEMENT.
Components
Processes
Dry Process
Wet Process
The document provides information about cement, including its history, chemical composition, manufacturing process, hydration, types of cement and tests conducted on cement. It begins with describing how cement is made from raw materials such as limestone, clay and iron ore through grinding, heating and cooling processes. It then discusses the chemistry and reactions involved in cement hydration. The document also lists and describes common types of cement used in construction, such as ordinary Portland cement, rapid hardening cement, white cement, as well as tests to measure cement consistency, setting time and strength.
Powerpoint presentation on CEMENT {PPT}Prateek Soni
Cement is a mixture of calcareous, siliceous, and argillaceous substances that is used as a binding agent in construction. It is produced through a process involving mixing raw materials, burning in a rotary kiln, and grinding the clinker produced. The manufacturing process can be either dry or wet. Key tests are conducted on cement to check properties like strength, color, presence of lumps, and solubility in water. There are various types of cement suited for different applications.
Cement is produced by heating limestone and clay at high temperatures to form clinker, which is then ground with gypsum. The key compounds formed are tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite. When mixed with water, cement undergoes hydration reactions that cause it to harden over time. Tricalcium silicate reacts rapidly and contributes to early strength, while dicalcium silicate reacts slowly and provides later strength. Tricalcium aluminate also reacts quickly but is retarded by gypsum addition. The reactions are exothermic and generate heat.
The document discusses different types of cement. It defines cement and describes its composition and manufacturing process. The main types discussed are ordinary Portland cement (OPC), Portland pozzolana cement (PPC), Portland blast furnace slag cement (PBSF), rapid hardening cement, low heat cement, sulfate resisting cement, and white cement. It provides details on the characteristics and common applications of each cement type.
Cement is topic;like and give credit for my free work
cement
cement and its types
Manufacturing of cement
uses of cement
wet process
dry process
portland cement
raw materials used in cement
field tests for cement
Cement is produced through a process involving crushing, grinding, and burning of limestone and clay. Joseph Aspdin first produced Portland cement in 1824. The first cement factory in India was established in Tamil Nadu in 1904. Cement production involves quarrying raw materials, crushing them, mixing with water or dry process, grinding, burning at high temperatures to form clinker, cooling clinker, and final grinding with gypsum. Cement is used widely in construction activities like building, roads, bridges due to its binding properties and high compressive strength.
Cement is a binding agent that sets and hardens after mixing with water. Romans first developed hydraulic cement by mixing volcanic ash with lime. Portland cement, the most common type today, was invented in 1824 and consists of calcium silicates and other compounds. It is produced through a process of grinding raw materials like limestone and clay, heating the mixture in a kiln to form clinker, then grinding the clinker with gypsum. The clinker compounds hydrate and harden when mixed with water. Cement is primarily used to bind sand, gravel and water into concrete for construction applications.
Ordinary Portland cement is the most widely used type of cement globally, with over 1.5 billion tons produced annually. It is manufactured through a wet or dry process involving crushing and mixing limestone and clay, heating the mixture in a rotary kiln to form clinker, grinding the clinker with gypsum. When mixed with water, it undergoes hydration reactions where compounds in the cement chemically react and harden over time, giving cement its strength. Ordinary Portland cement is used in general construction like buildings and bridges due to its strength and resistance to cracking, though it has less chemical resistance than other cements.
Cement is a binding material made of calcareous, siliceous, and argillaceous substances. There are various types of cement used for different purposes, including ordinary Portland cement, rapid hardening cement, extra rapid hardening cement, sulphate resisting cement, quick setting cement, low heat cement, Portland pozzolana cement, Portland slag cement, high alumina cement, air entraining cement, supersulphated cement, masonry cement, expansive cement, colored cement, and white cement. The document discusses the chemical composition and functions of cement constituents and manufacturing processes.
Cement is a binding material made by burning limestone and clay at high temperatures. It is composed mainly of calcium oxides, silica, aluminum, and iron. There are different types of cement used for various purposes based on setting time and chemical resistance. Cement undergoes hydration when mixed with water, resulting in a chemical reaction that causes it to harden. The setting and hardening process allows cement to be used to bind aggregates like sand and gravel into concrete. Cement is tested for consistency, strength development over time, and other characteristics to ensure it meets specifications.
The document provides information on the process of determining the fineness of cement through dry sieving. It involves weighing 10g of cement and placing it on a 90μm sieve. The sieve is agitated to allow fine material to pass through while retaining particles larger than 90μm. The residue is weighed and reported as a percentage of the original sample weight. This process is repeated and the mean percentage residue is calculated to determine the fineness of the cement sample.
Cement is produced through a process involving mixing raw materials like limestone and clay, burning the mixture in a kiln at high temperatures, and finely grinding the resulting clinker. It is used as a binding agent in materials like mortar and concrete. The consistency test determines the appropriate water-cement ratio needed to produce a cement paste with normal consistency for standard strength tests. A Vicat apparatus is used to measure penetration of a needle into the paste, with a reading between 30-35mm below the surface considered standard consistency. There are various types of cement used for different purposes and properties.
Portland cement is produced through a four step process:
1) Limestone and other raw materials are quarried and crushed
2) The raw materials are ground and blended to ensure proper chemical composition
3) The raw materials are heated in a kiln to over 1400°C, undergoing chemical reactions to form the four main compounds that make up cement
4) The resulting clinker is ground with gypsum to produce the fine powder that is Portland cement
Popular as Building material.
Material with adhesive and cohesive properties.
To bind the fine and corse aggregate together.
Common variety of cement is known as the Portland cement.
India is the fifth largest producer of cement in the world.
Rajasthan is the second largest producer of cement in india after Andra Pradesh.
This document provides information on ordinary Portland cement grade 53, including its definition, history, manufacturing process, chemical and physical requirements, and uses. Key points:
- Cement is made from limestone, clay, and other materials that are heated to form clinker and then ground with gypsum.
- The manufacturing process involves quarrying raw materials, crushing, grinding, burning at high temperatures, cooling clinker, and grinding it with gypsum to form cement.
- Cement must meet chemical requirements for composition and physical requirements for things like setting time and strength.
- The main uses of cement are in concrete and mortar for construction of buildings, infrastructure, and more.
The document discusses the manufacturing process of cement. It begins with crushing and mixing of raw materials such as limestone, clay, and iron ore. The raw materials are then heated in a kiln to form clinker. Clinker is ground into a fine powder to produce cement. When mixed with water, cement undergoes chemical reactions that result in hardening over time as it hydrates. The hydration process involves calcium silicates and aluminates reacting with water to form compounds like calcium silicate hydrate and calcium aluminate hydrates.
This document discusses Portland cement and the cement manufacturing process. It begins with an overview of what cement is and how it is used to make concrete. It then describes the industrial process for manufacturing cement, involving grinding raw materials like limestone and clay at high temperatures in a kiln to form clinker, which is then pulverized with gypsum to become Portland cement powder. The document also provides a brief history of cement development and explains how cement kilns can beneficially reuse solid and hazardous wastes as a source of energy and raw material replacement due to the kilns' high temperatures and long retention times.
The document discusses the hydration of cement compounds. The four main compounds (Bogue's compounds) are tricalcium silicate (C3S), dicalcium silicate (C2S), tricalcium aluminate (C3A), and tetracalcium aluminoferrite (C4AF). C3S hydrates rapidly and provides early strength, while C2S hydrates slowly and provides later strength. C3A hydrates very fast unless gypsum is added, in which case it forms ettringite. C4AF hydrates similarly to C3A but more slowly. The hydration processes of the individual compounds involve formation of calcium silicate hydrate, calcium hydroxide
The document discusses the process of cement manufacturing. It begins with the raw materials used, which include limestone, clay, iron oxide, and aluminum. These materials are quarries, crushed, and transported to a plant for storage. They are then ground together and preheated before being burned in a kiln at 1500°C to produce clinker. The clinker is cooled, ground with gypsum, and stored in silos before being packaged and distributed. The document outlines the characteristics, types, grades, setting process, optimal storage conditions, and common uses of cement in construction.
- Portland cement is produced by heating limestone, clay, and other materials to form clinker, which is then ground with gypsum.
- The main compounds in clinker are tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite.
- The proportions of calcium oxide, silicon dioxide, aluminum oxide, and iron oxide in the raw materials determine the compound composition through Bogue equations.
This presentation summarizes the types and properties of cement. It discusses the history of cement and how it was first used by Egyptians. It then covers the main types of cement including grey cement (e.g. OPC, rapid hardening), white/colored cement, and blended cements (e.g. PPC, PSC). The presentation also outlines the physical properties of cement such as consistency, setting time, soundness, and fineness. Finally, it summarizes the chemical properties including the main compounds in cement and how they contribute to strength.
- Cement is tested in the field to check for lumps, consistency, and ability to float in water.
- Laboratory tests include setting time, soundness, fineness, and strength. Setting time tests use a Vicat apparatus to check initial and final set. Soundness tests use a Le Chatelier apparatus to check for expansion. Fineness is measured by the Blaine air permeability test. Strength is measured through compressive testing of cement mortar cubes.
- Common cement types include ordinary Portland cement, rapid hardening cement, sulphate resisting cement, Portland slag cement, and Portland pozzolana cement made by intergrinding clinker with fly ash or calcined clay.
This document summarizes the process for manufacturing portland cement. It begins by defining cement as a powder made from calcining limestone and clay, which can be mixed with water or sand and gravel to make mortar or concrete. The main raw materials are limestone and chalk or shale and clay. The manufacturing process involves grinding these raw materials, mixing them intimately in a kiln at 1300-1500°C to form clinkers, which are then ground into a fine powder along with gypsum to make portland cement. There are two main processes - wet and dry - which differ in whether raw materials are ground with or without water during mixing and grinding. The wet process allows for more accurate mixing but the dry process
This document provides information about refractory materials. It defines refractories as materials that can withstand high temperatures, chemical reactions, and physical stresses. The document discusses the global refractory production market share, common industrial uses of refractories, and key properties such as melting point, density, and thermal expansion. It also describes common refractory materials like silica bricks and magnesia bricks, explaining their composition, manufacturing processes, and applications.
Cement is produced by heating limestone and clay at high temperatures. This causes them to chemically combine and form small balls called clinker. Clinker is then ground with gypsum into a powder to create cement. When mixed with water, cement forms a paste that binds sand, gravel and crushed rock together to form concrete. The key steps in cement production are grinding raw materials, firing the mixture in a kiln at over 1300°C to produce clinker, cooling the clinker, and grinding it with gypsum into the final cement powder. Different types of cement are produced by varying the chemical composition and fineness to achieve specific properties like rapid setting, low heat generation, or sulfate resistance.
The document describes 7 different tests conducted on cement:
1. Field testing examines the cement's appearance, texture, and behavior when mixed with water.
2. The standard consistency test determines the percentage of water needed to achieve a standardized consistency for cement paste.
3. The fineness test evaluates the particle size distribution of cement, with finer particles offering a greater surface area for hydration.
4. The soundness test ensures cement does not expand after setting, which could indicate excess lime causing unsoundness.
5. The strength test measures the compressive strength of cement mortar mixtures at various ages (3, 7, 28 days).
6. The heat of hydration test examines the heat released
Cement is produced through a process involving mixing and crushing raw materials like limestone and clay, burning the materials in a kiln, and grinding the resulting clinker. The main raw materials are limestone, silica, alumina, and iron oxide. The wet process involves grinding materials into a slurry while the dry process uses powdered materials. The slurry or powder is burned at high temperatures to produce clinker, which is then ground into cement powder. Different types of cement include ordinary Portland cement, sulfate resisting cement, and rapid hardening cement. Cement quality is tested through fineness, setting time, and compressive strength tests.
Cement is a powdery material that binds other materials together when mixed with water. It is made through a process of crushing raw materials like limestone, mixing them into a slurry or powder, burning the mixture in a kiln, and finely grinding the resulting clinker. The most common type is Portland cement, which is a finely ground powder that sets and hardens through chemical reactions with water. Cement is widely used in construction for buildings, infrastructure, and other applications due to its ability to form strong structures and conform to various shapes.
Ordinary Portland cement is the most widely used type of cement globally, with over 1.5 billion tons produced annually. It is manufactured through a wet or dry process involving crushing and mixing limestone and clay, heating the mixture in a rotary kiln to form clinker, grinding the clinker with gypsum. When mixed with water, it undergoes hydration reactions where compounds in the cement chemically react and harden over time, giving cement its strength. Ordinary Portland cement is used in general construction like buildings and bridges due to its strength and resistance to cracking, though it has less chemical resistance than other cements.
Cement is a binding material made of calcareous, siliceous, and argillaceous substances. There are various types of cement used for different purposes, including ordinary Portland cement, rapid hardening cement, extra rapid hardening cement, sulphate resisting cement, quick setting cement, low heat cement, Portland pozzolana cement, Portland slag cement, high alumina cement, air entraining cement, supersulphated cement, masonry cement, expansive cement, colored cement, and white cement. The document discusses the chemical composition and functions of cement constituents and manufacturing processes.
Cement is a binding material made by burning limestone and clay at high temperatures. It is composed mainly of calcium oxides, silica, aluminum, and iron. There are different types of cement used for various purposes based on setting time and chemical resistance. Cement undergoes hydration when mixed with water, resulting in a chemical reaction that causes it to harden. The setting and hardening process allows cement to be used to bind aggregates like sand and gravel into concrete. Cement is tested for consistency, strength development over time, and other characteristics to ensure it meets specifications.
The document provides information on the process of determining the fineness of cement through dry sieving. It involves weighing 10g of cement and placing it on a 90μm sieve. The sieve is agitated to allow fine material to pass through while retaining particles larger than 90μm. The residue is weighed and reported as a percentage of the original sample weight. This process is repeated and the mean percentage residue is calculated to determine the fineness of the cement sample.
Cement is produced through a process involving mixing raw materials like limestone and clay, burning the mixture in a kiln at high temperatures, and finely grinding the resulting clinker. It is used as a binding agent in materials like mortar and concrete. The consistency test determines the appropriate water-cement ratio needed to produce a cement paste with normal consistency for standard strength tests. A Vicat apparatus is used to measure penetration of a needle into the paste, with a reading between 30-35mm below the surface considered standard consistency. There are various types of cement used for different purposes and properties.
Portland cement is produced through a four step process:
1) Limestone and other raw materials are quarried and crushed
2) The raw materials are ground and blended to ensure proper chemical composition
3) The raw materials are heated in a kiln to over 1400°C, undergoing chemical reactions to form the four main compounds that make up cement
4) The resulting clinker is ground with gypsum to produce the fine powder that is Portland cement
Popular as Building material.
Material with adhesive and cohesive properties.
To bind the fine and corse aggregate together.
Common variety of cement is known as the Portland cement.
India is the fifth largest producer of cement in the world.
Rajasthan is the second largest producer of cement in india after Andra Pradesh.
This document provides information on ordinary Portland cement grade 53, including its definition, history, manufacturing process, chemical and physical requirements, and uses. Key points:
- Cement is made from limestone, clay, and other materials that are heated to form clinker and then ground with gypsum.
- The manufacturing process involves quarrying raw materials, crushing, grinding, burning at high temperatures, cooling clinker, and grinding it with gypsum to form cement.
- Cement must meet chemical requirements for composition and physical requirements for things like setting time and strength.
- The main uses of cement are in concrete and mortar for construction of buildings, infrastructure, and more.
The document discusses the manufacturing process of cement. It begins with crushing and mixing of raw materials such as limestone, clay, and iron ore. The raw materials are then heated in a kiln to form clinker. Clinker is ground into a fine powder to produce cement. When mixed with water, cement undergoes chemical reactions that result in hardening over time as it hydrates. The hydration process involves calcium silicates and aluminates reacting with water to form compounds like calcium silicate hydrate and calcium aluminate hydrates.
This document discusses Portland cement and the cement manufacturing process. It begins with an overview of what cement is and how it is used to make concrete. It then describes the industrial process for manufacturing cement, involving grinding raw materials like limestone and clay at high temperatures in a kiln to form clinker, which is then pulverized with gypsum to become Portland cement powder. The document also provides a brief history of cement development and explains how cement kilns can beneficially reuse solid and hazardous wastes as a source of energy and raw material replacement due to the kilns' high temperatures and long retention times.
The document discusses the hydration of cement compounds. The four main compounds (Bogue's compounds) are tricalcium silicate (C3S), dicalcium silicate (C2S), tricalcium aluminate (C3A), and tetracalcium aluminoferrite (C4AF). C3S hydrates rapidly and provides early strength, while C2S hydrates slowly and provides later strength. C3A hydrates very fast unless gypsum is added, in which case it forms ettringite. C4AF hydrates similarly to C3A but more slowly. The hydration processes of the individual compounds involve formation of calcium silicate hydrate, calcium hydroxide
The document discusses the process of cement manufacturing. It begins with the raw materials used, which include limestone, clay, iron oxide, and aluminum. These materials are quarries, crushed, and transported to a plant for storage. They are then ground together and preheated before being burned in a kiln at 1500°C to produce clinker. The clinker is cooled, ground with gypsum, and stored in silos before being packaged and distributed. The document outlines the characteristics, types, grades, setting process, optimal storage conditions, and common uses of cement in construction.
- Portland cement is produced by heating limestone, clay, and other materials to form clinker, which is then ground with gypsum.
- The main compounds in clinker are tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite.
- The proportions of calcium oxide, silicon dioxide, aluminum oxide, and iron oxide in the raw materials determine the compound composition through Bogue equations.
This presentation summarizes the types and properties of cement. It discusses the history of cement and how it was first used by Egyptians. It then covers the main types of cement including grey cement (e.g. OPC, rapid hardening), white/colored cement, and blended cements (e.g. PPC, PSC). The presentation also outlines the physical properties of cement such as consistency, setting time, soundness, and fineness. Finally, it summarizes the chemical properties including the main compounds in cement and how they contribute to strength.
- Cement is tested in the field to check for lumps, consistency, and ability to float in water.
- Laboratory tests include setting time, soundness, fineness, and strength. Setting time tests use a Vicat apparatus to check initial and final set. Soundness tests use a Le Chatelier apparatus to check for expansion. Fineness is measured by the Blaine air permeability test. Strength is measured through compressive testing of cement mortar cubes.
- Common cement types include ordinary Portland cement, rapid hardening cement, sulphate resisting cement, Portland slag cement, and Portland pozzolana cement made by intergrinding clinker with fly ash or calcined clay.
This document summarizes the process for manufacturing portland cement. It begins by defining cement as a powder made from calcining limestone and clay, which can be mixed with water or sand and gravel to make mortar or concrete. The main raw materials are limestone and chalk or shale and clay. The manufacturing process involves grinding these raw materials, mixing them intimately in a kiln at 1300-1500°C to form clinkers, which are then ground into a fine powder along with gypsum to make portland cement. There are two main processes - wet and dry - which differ in whether raw materials are ground with or without water during mixing and grinding. The wet process allows for more accurate mixing but the dry process
This document provides information about refractory materials. It defines refractories as materials that can withstand high temperatures, chemical reactions, and physical stresses. The document discusses the global refractory production market share, common industrial uses of refractories, and key properties such as melting point, density, and thermal expansion. It also describes common refractory materials like silica bricks and magnesia bricks, explaining their composition, manufacturing processes, and applications.
Cement is produced by heating limestone and clay at high temperatures. This causes them to chemically combine and form small balls called clinker. Clinker is then ground with gypsum into a powder to create cement. When mixed with water, cement forms a paste that binds sand, gravel and crushed rock together to form concrete. The key steps in cement production are grinding raw materials, firing the mixture in a kiln at over 1300°C to produce clinker, cooling the clinker, and grinding it with gypsum into the final cement powder. Different types of cement are produced by varying the chemical composition and fineness to achieve specific properties like rapid setting, low heat generation, or sulfate resistance.
The document describes 7 different tests conducted on cement:
1. Field testing examines the cement's appearance, texture, and behavior when mixed with water.
2. The standard consistency test determines the percentage of water needed to achieve a standardized consistency for cement paste.
3. The fineness test evaluates the particle size distribution of cement, with finer particles offering a greater surface area for hydration.
4. The soundness test ensures cement does not expand after setting, which could indicate excess lime causing unsoundness.
5. The strength test measures the compressive strength of cement mortar mixtures at various ages (3, 7, 28 days).
6. The heat of hydration test examines the heat released
Cement is produced through a process involving mixing and crushing raw materials like limestone and clay, burning the materials in a kiln, and grinding the resulting clinker. The main raw materials are limestone, silica, alumina, and iron oxide. The wet process involves grinding materials into a slurry while the dry process uses powdered materials. The slurry or powder is burned at high temperatures to produce clinker, which is then ground into cement powder. Different types of cement include ordinary Portland cement, sulfate resisting cement, and rapid hardening cement. Cement quality is tested through fineness, setting time, and compressive strength tests.
Cement is a powdery material that binds other materials together when mixed with water. It is made through a process of crushing raw materials like limestone, mixing them into a slurry or powder, burning the mixture in a kiln, and finely grinding the resulting clinker. The most common type is Portland cement, which is a finely ground powder that sets and hardens through chemical reactions with water. Cement is widely used in construction for buildings, infrastructure, and other applications due to its ability to form strong structures and conform to various shapes.
Portland cement was first patented in 1824 by Joseph Aspdin. It is made by heating limestone and clay at high temperatures in a kiln, which produces cement clinker. The clinker is then ground into a fine powder that sets and hardens when mixed with water. The hydration process involves chemical reactions between the cement compounds (C3S, C2S, C3A, C4AF) and water that produce heat and calcium silicate hydrates and calcium hydroxide, binding the concrete mixture. Cement is tested for fineness, setting time, soundness, and strength to ensure quality control.
This document discusses different types of admixtures used in concrete, including their uses and effects. It covers mineral admixtures like fly ash and silica fume that can reduce costs and improve properties. It also discusses chemical admixtures, specifically highlighting water reducers, superplasticizers, accelerators, and retarders. Water reducers and superplasticizers can lower the water-cement ratio while maintaining workability, leading to increased strength. Accelerators can reduce setting time while retarders have the opposite effect of delaying setting.
1) Cement is a substance used to bind together sand and aggregates like stone. Hydraulic cement forms water resistant products when mixed with water.
2) The main chemical compounds in Portland cement are tri-calcium silicate (C3S), di-calcium silicate (C2S), tri-calcium aluminate (C3A), and tetra-calcium aluminoferrite (C4AF).
3) When mixed with water, cement undergoes hydration reactions where the compounds react to form products like calcium silicate hydrates and calcium hydroxide that harden and bind the materials together.
Portland cement is produced by heating limestone, clay, and other materials in a kiln to form clinker, which is then ground with gypsum. The key compounds formed are tricalcium silicate (C3S), dicalcium silicate (C2S), tricalcium aluminate (C3A), and tetracalcium aluminoferrite (C4AF). Their proportions can be estimated using Bogue's equations based on the oxide composition measured through chemical analysis. The document provides details on the production process, chemical reactions, composition standards, and example calculations.
The document provides an overview of the cement industry in India. It discusses that cement is made from limestone, shale, clay and iron ore. It then outlines the various types of cement produced. The manufacturing process and key raw materials are also summarized. The document highlights that India is the second largest cement producer globally. It provides statistics on the growth, investments, exports and contribution to GDP of the Indian cement industry. The major players in the industry are also listed along with issues faced and the structural drivers shaping the industry.
1. The document discusses the hydration process of cement, which involves a series of irreversible chemical reactions between cement and water. This leads to the formation of hydration products over time, causing the cement paste to stiffen, set, and harden.
2. There are five stages of cement hydration: mixing/dissolution, dormant period, acceleration, deceleration, and densification. The hydration reactions produce compounds like calcium silicate hydrate (C-S-H) and calcium hydroxide (CH) that provide strength to the concrete.
3. Factors that affect the hydration process include the chemical composition of cement, cement type, sulfate content, fineness,
This document provides an overview of concrete ingredients and their properties. It discusses that concrete is composed of a binding medium (cement) and aggregates (sand and gravel) held together by water. Portland cement is the most common type of cement used due to its availability and properties. The document outlines the manufacturing processes for Portland cement and describes different cement types. It also discusses tests performed on cement to ensure quality, including fineness, setting time, consistency and compressive strength. Concrete's widespread use is attributed to its resistance to water, ability to be molded, and relatively low cost.
Internship report-2 D.G cement company limited (d.g khan)Zuhair Bin Jawaid
Muhammad Yousif Gurmani completed an internship at D.G. Khan Cement Company Limited (DGKCC) in Lahore, Pakistan. DGKCC is one of the largest cement manufacturers in Pakistan, with a production capacity of 5,500 tons of clinker per day. During his internship, Gurmani learned about the various processes involved in cement production, including limestone and clay crushing, grinding in raw mills and coal mills, heating in kilns, cement grinding, packing, and quality control. He observed these processes firsthand at the different sections of the DGKCC plant over the course of his internship.
This presentation provides an overview of cement industries. It defines cement as a powdered material that hardens when mixed with water. There are four main types of cement: Portland, pozzolana, calcium aluminate, and special or corrosion resistant cement. The history, manufacturing process, raw materials, reactions, and uses of cement are described. Cement production involves mining limestone and clay, crushing and mixing them, burning the mixture in a kiln to form clinker, and grinding the clinker with gypsum. The main constituents of cement are lime, silica, alumina, and iron oxide. Cement is primarily used in construction applications such as buildings, roads, bridges, and more.
Portland Cements, Calcium and Magnesium CompoundsZanny Barluado
This document provides an overview of Portland cements and related calcium and magnesium compounds. It discusses the history and development of Portland cement by Joseph Aspdin in 1824. It describes the manufacturing process which involves mining limestone and clay, grinding and heating the materials in a kiln to form clinker, and then grinding the clinker with gypsum to produce cement. Different types of Portland cement are outlined based on their properties and uses. Other cements like pozzolanic and high alumina cements are also discussed. Key calcium compounds like limestone, lime, and their uses are summarized. The manufacturing process for lime is outlined.
Portland Cement
Portland cement is extensively used in the construction of nuclear waste facilities and as a matrix for shielding and immobilization of radioactive species. It affords both a physical and chemical potential for immobilization. These potentials are quantified and related to specification, fabrication, and performance. However, performance in the long term depends on the cement formulation as well as the geochemistry of the disposal environment and interactions between cement and its near field environment including inactive waste components and other containment materials. Future performance can be estimated using data from natural analogs,
the experience of the performance of historic structures, and by modeling. A comparison of Portland cement with other non-Portland cement is also made.
This document discusses different types of cement. It describes ordinary Portland cement as the most widely used type, and also discusses low heat cement, rapid hardening cement, sulphate resistant cement, and white/colored cement. Each type has different compositions and properties that make them suitable for specific construction applications. For example, low heat cement produces less heat during curing to prevent cracking in large concrete structures, while sulphate resistant cement provides protection against sulfate attack in foundations or other applications exposed to sulfate salts.
Cement is produced by heating limestone and clay in a kiln to form clinker, which is then ground with gypsum. There are two main types: hydraulic cement hardens when mixed with water due to a chemical reaction, while non-hydraulic cement hardens through carbonation. The Romans used early forms of concrete and cement in structures like the Colosseum. Modern cement production involves mining raw materials, grinding and heating them to form clinker, and then grinding the clinker to produce cement powder. Cement is used primarily in concrete and mortar for construction of buildings, roads, bridges and other infrastructure.
This presentation discusses cement industries and the process of cement manufacturing. It begins by defining Portland cement as a powdered material that hardens when mixed with water. There are various types of Portland cement depending on setting rate and strength. The manufacturing process involves mining limestone and clay as raw materials, grinding them, heating the mixture in a kiln to form clinker, and grinding the clinker with gypsum. The reactions that occur in the kiln form the key compounds that provide strength. Cement is an important building material used in construction of structures like roads, buildings and bridges.
Cement is produced by burning limestone and clay at high temperatures. It was first produced commercially in England in 1842. The main ingredients in cement are lime, silica, alumina and iron oxide. When water is added, cement undergoes hydration, hardening over time. There are different types of cement used for various purposes, such as pozzolana cement, which has stronger water resistance, and blast furnace slag cement, which is more durable but gains strength slowly. Cement is widely used in construction for buildings, bridges, roads and more.
Cement is a binding material made of a mixture of calcareous, siliceous, and argillaceous substances. There are two main processes for manufacturing cement - the dry process and wet process. In the dry process, raw materials are ground without water, while in the wet process water is added during grinding. The ground raw materials are then burned in a kiln at high temperatures to form clinker, which is then ground with gypsum. There are different types of cement used for various purposes, and cement is tested for qualities like fineness, setting time, and compressive strength.
Cement class 12 notes of cement chapter.pdfSafalPoudel6
Cement is produced through a process involving crushing and grinding raw materials such as limestone and clay, heating the materials in a kiln to form clinker, cooling and grinding the clinker, and adding gypsum. The main raw materials used are limestone, clay, iron oxide, and aluminum oxide. During the heating process in a rotary kiln, the raw materials undergo chemical reactions to form calcium silicates and calcium aluminates which fuse together to form clinker. Gypsum is added to the ground clinker to regulate the setting time of cement.
The document provides information on a presentation about different types of cement. It discusses the definition and constituents of cement. It then covers the history of cement use in Nepal. The main types of cement discussed include Ordinary Portland Cement (OPC), Portland Pozzolana Cement, Rapid Hardening Cement, Extra Rapid Hardening Cement, Sulphate Resisting Cement, and others. For each type, the document outlines their manufacturing process, properties, and common uses.
This document provides information on concrete, including its common components, production processes, and types of cement. It discusses the key ingredients of concrete - cement, coarse aggregate, fine aggregate, and water. It also describes the manufacturing of Portland cement, different types of cement including rapid hardening, low heat, and sulfate resisting cements. The document outlines methods for batching, mixing, transporting, curing and testing concrete. Reinforcement and additives that can be used in concrete are also mentioned.
This document discusses concrete technology and testing methods. It defines concrete as a hard building material formed from a mixture of cement, sand, gravel, and water through hydration. It categorizes concrete based on compressive strength and lists its typical components and properties. Several types of Portland cement are described based on their chemical compounds and intended uses. Finally, various AASHTO test methods are outlined for evaluating properties of fresh and hardened concrete such as slump, density, air content, temperature, consistency, compressive strength, and flexural strength.
This document provides an overview of cement, including its history, main chemical compounds, properties, hydration process, setting, and types. It discusses how Joseph Aspdin first produced Portland cement in 1824 and how cement production has expanded globally. The four main compounds in Portland cement are tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite. The document also examines cement's physical properties like fineness and strength, as well as the hydration and setting processes. Different cement types include ASTM Types I-V as well as masonry cement and natural cement.
The document provides information on cement, including its history, chemical composition, manufacturing process, and hydration. It discusses how cement is made by heating limestone, clay, and other materials in a kiln to form clinker, which is then ground with gypsum. The manufacturing process involves quarrying limestone, grinding raw materials, sintering in a rotary kiln at high temperatures, cooling the clinker, and final grinding with gypsum. Hydration of cement occurs as its compounds (C3S, C2S, C3A, C4AF) react with water, releasing heat and forming hydrates that harden the concrete.
Concrete Technology Introduction By DR. Vishwanath KantheBhavesh Bagul
The document discusses the key ingredients of concrete including cement, fine aggregate, coarse aggregate, and water. It provides details on the properties and testing of cement and aggregates.
Cement is the most important ingredient and is made by grinding raw materials like limestone and clay and burning them in a kiln. The chemical composition and hydration process of cement are described. Different types of cement like ordinary Portland cement and sulfate resisting cement are also mentioned.
The properties of aggregates like size, shape, texture and strength are outlined. Tests for properties like specific gravity, water absorption and sieve analysis are noted. The effect of aggregate size and shape on concrete properties is summarized.
Here are the steps to solve this nominal mix design problem based on mass:
1) Given: Cement mass = 150 kg
Mix ratio = 1:2:4
Densities:
Cement = 1440 kg/m3
Fine aggregate = 1640 kg/m3
Coarse aggregate = 1390 kg/m3
2) Calculate cement volume:
Cement mass / Cement density = Volume
150 kg / 1440 kg/m3 = 0.104 m3
3) Calculate fine aggregate volume based on mix ratio:
Cement volume x Fine aggregate ratio = Fine aggregate volume
0.104 m3 x 2 = 0.208 m3
The objectives of this course in iron ore Resources and iron industry are:
i) acquainting students (majors and non-majors) with the basic tools necessary for studying iron ore deposits and processes,
ii) different processes for phosphorus removal from iron ore
iii) beneficiation processes of iron ore deposits.
iv) different processes and techniques that used to enrichment low-grade iron ore resources
v) understanding the different ironwork processes and technology,
vi) understanding the different types of iron ore products,
vii) prominent routes for steelmaking
viii) understanding the relationship between the distribution of iron ore and scrap, as well as steelmarkets,
ix) steel industry in Egypt , and
x) gaining some knowledge of the global iron ore as well as environmental problems associated with the extraction and utilization of iron ore resources.
There are plenty of hard-to-beneficiate iron ores and high-grade tailings in India and all over the world; As the volume of high-grade iron ores declines.
Minerals phase transformation by hydrogen reduction (MPTH) can efficiently revitalize hard-to-beneficiate iron ore resources and tailings, turning the waste into profitable products. It may also improve the concentrate quality comparing to that from the previous method. From the economic and environmental aspects, MPTH is the most effective method to recover iron oxides.
The clean minerals phase transformation by hydrogen reduction (MPTH) was proposed.
Industrial utilization of limonite/goethite, limonite-hematite, sulfur-bearing refractory iron ore was achieved, where Sulfur-bearing minerals decomposed or formed sulfate after oxidation roasting.
Sulfur content of iron ore concentrate was significantly reduced to 0.038 %.
Improving utilization efficiency of refractory iron ore resources is a common theme for the sustainable development of the world’s steel and iron industry.
Magnetization Roasting is considered as an effective and typical method for the beneficiation of refractory iron ores.
After magnetization roasting, the weakly magnetic iron minerals, including hematite, limonite and siderite, are selectively reduced or oxidized to ferromagnetic magnetite, which is relatively easier to enrich by Magnetic Separation after liberation pretreatments.
The Primary Magnetization Roasting Methods include: Shaft Furnace Roasting, Rotary Kiln Roasting, Fluidized Bed Roasting, and Microwave assisted roasting. The developments in magnetization roasting of difficult to treat iron ores, including: Shaft Furnace Roasting, Rotary Kiln Roasting, Fluidized Bed Roasting, and Microwave Assisted Roasting in the Past Decade.
Shaft Furnace Roasting is gradually eliminated due to its high energy consumption and low industrial processing capacity, and the primary problem for rotary kiln roasting is the kiln coating which affects the yield of iron resource and its industrial application.
Fluidized Bed Roasting and Microwave assisted roasting are considered as the most effective and promising methods.
Suspension (Fluidized) Magnetization Roasting is recognized as the most effective and promising technology due to its high reaction efficiency, low energy consumption and large processing capacity. Moreover, an industrial production line with a throughput of 1.65 million t/a for beneficiation of a specularite ore has been built.
Microwave Assisted Roasting is a potential alternative technology for magnetizing iron ores. However, it is currently limited to laboratory research and has no industrial application. Forwarding microwave assisted magnetization roasting methods into industrial applications needs long way and time to achieve.
Furthermore, using biomass, H2 or siderite as a reducing agent in the magnetic reduction roasting of iron ores is a beneficial way to reduce carbon emissions, which can be called clean and green magnetization roasting technology.
In the future, technical research on clean and green magnetization roasting should be strengthened. Maybe microwave magnetization roasting using biomass/H2/siderite as reductant can be further studied for a more effective and greener magnetization of iron ores.
WORLD RESOURCES IRON DEPOSITS
Iron Ore Pellets Market Industry Trends
Scope and Market Size
Market Analysis and Insights
DRI Production in Plants Using Merchant Iron Ore
Outlook for DR grade pellet supply‐demand out to 2030
DRI and the pathway to carbon‐neutral steelmaking
Supply‐side challenges for the steel & iron ore industries
scrap is the main raw material, is growing in the structure of global steelmaking capacities; SCARP/ RECYCLING IRON ; EAF steel production method in the world; Scrap for Stock; A Global Scrap Shortage;Availability of Ferrous Scrap Resources; EGYPT IRON SCRAP IMPORTS.
The iron ore production has significantly expanded in recent years, owing to increasing steel demands in developing countries.
However, the content of iron in ore deposits has deteriorated and low-grade iron ore has been processed.
The fine ores resulting from the concentration process must be agglomerated for use in iron and steelmaking.
Bentonite is the most used binder due to favorable mechanical and metallurgical pellet properties, but it contains impurities especially silica and alumina.
Better quality wet, dry, preheated, and fired pellets can be produced with combined binders, such as organic and inorganic salts, when compared with bentonite-bonded pellets.
While organic binders provide sufficient wet and dry pellet strengths, inorganic salts provide the required preheated and fired pellet strengths.
The industrial development program of any country, by and large, is based on its natural resources.
Currently the majority of the world’s steel is produced through either one of the two main routes: i) the integrated Blast Furnace – Basic Oxygen Furnace (BF – BOF) route or ii) the Direct Reduced Iron - Electric Arc Furnace (DRI - EAF) route.
Depleting resources of coking coal, the world over, is posing a threat to the conventional (Blast Furnace [Bf]–Basic Oxygen Furnace [BOF]) route of iron and steelmaking.
During the last four decades, a new route of ironmaking has rapidly developed for Direct Reduction (DR) of iron ore to metallic iron by using noncoking coal/natural gas.
This product is known as Direct Reduced Iron (DRI) or Sponge Iron.
Processes that produce iron by reduction of iron ore (in solid state) below the melting point are generally classified as DR processes.
Based on the types of reductant used, DR processes can be broadly classified into two groups: (1) coal-based DR process and (2) gas-based DR process.
Details of DR processes, reoxidation, storage, transportation, and application of DRI are discussed in this presentation.
This presentation reviews the different DR processes used to produce Direct Reduced Iron (DRI), providing an analysis on the quality requirements of iron-bearing ores for use in these processes. The presentation also discusses the environmental sustainability of such processes. DR processes reduce iron ore in its solid state by the use of either natural gas or coal as reducing agents, and they have a comparative advantage of low capital costs, low emissions and production flexibility over the BF process.
Currently the majority of the world’s steel is produced through either one of the two main routes: i) the integrated Blast Furnace – Basic Oxygen Furnace (BF – BOF) route or ii) the Direct Reduced Iron - Electric Arc Furnace (DRI - EAF) route.
In the former, the blast furnace uses iron ore, scrap metal, coke and pulverized coal as raw materials to produce hot metal for conversion in the BOF. Although it is still the prevalent process, blast furnace hot metal production has declined over the years due to diminishing quality of metallurgical coke, low supply of scrap metal and environmental problems associated with the process. These factors have contributed to the development of alternative technologies of ironmaking, of which Direct Reduction (DR) processes are expected to emerge as preferred alternatives in the future.
This presentation reviews the different DR processes used to produce Direct Reduced Iron (DRI), providing an analysis on the quality requirements of iron-bearing ores for use in these processes. The presentation also discusses the environmental sustainability of such processes. DR processes reduce iron ore in its solid state by the use of either natural gas or coal as reducing agents, and they have a comparative advantage of low capital costs, low emissions and production flexibility over the BF process.
Ironmaking represents the first step in steelmaking.
The iron and steel industry is the most energy-intensive and capital-intensive manufacturing sector in the world (Strezov, 2006).
Steelmaking processes depend on different forms of iron as primary feed material. Traditionally, the main sources of iron for making steel were Blast Furnace hot metal and recycled steel in the form of scrap.
The Blast Furnace (BF) has remained the workhorse of worldwide virgin iron production (i.e., hot metal) for more than 200 years. Over the years, BFs have evolved into highly efficient chemical reactors, capable of providing stable operation with a wide range of feed materials.
However, operation of modern efficient BFs normally involves sintering and coke making and their associated environmental problems.
More than 90% of iron is currently produced via the BF process, while the rest is coming from Direct Reduction (DR) processes, Mini Blast Furnaces (MBFs), Corex, Finex, Ausmelt, etc. Additionally, the severe shortage of good-quality metallurgical coal has remained an additional constraint all over the world. In view of this, there is an increasing awareness that the BF route needs to be supplemented with alternative ironmaking processes that are more environment friendly and less dependent on metallurgical coal.
The document discusses reduction roasting followed by magnetic separation as a promising technique for enriching iron values from low-grade iron ores. It provides an overview of the technique, noting that reduction roasting involves reducing hematite and goethite phases in iron ores to magnetite, which can then be separated magnetically. The document reviews reduction roasting studies on various types of low-grade iron ores, including oolitic iron ores, banded iron ores, iron ore slimes and tailings. Emerging trends in reduction roasting such as microwave-assisted and biomass-assisted methods are also examined.
Phosphorus removal from iron ore is important for efficient steelmaking. Various processes have been developed to reduce phosphorus levels prior to smelting, including physical separation techniques that leverage differences in particle properties, and chemical/hydrometallurgical methods utilizing reagents to selectively remove or transform phosphorus. Further optimization is needed to improve phosphorus removal efficiency and minimize environmental impacts.
Overview of IRON TYPES: Pig Iron, Direct Reduced Iron (DRI), Hot Briquetted Iron (HBI), Cold Briquetted Iron (CBI) and Cold Briquetted Iron and Carbon (CBIC) Specifications .
Comparison of Pig Iron and DRI
Properties; Manufacturing Process; Uses; Largest producers and markets
Iron ore mining plays a critical role in supplying the raw material necessary for steel production, supporting various industries and economic development worldwide.
From the extraction of iron ore to its processing and eventual export, each stage of the mining process requires careful planning, technological advancements, and environmental considerations.
By adopting sustainable mining practices and mitigating environmental impacts, the future of iron ore mining can be aligned with the principles of responsible resource utilization and environmental stewardship
The Egyptian steel sector is the second largest steel market in the Middle East and North Africa region in terms of production and third largest in terms of consumption.
Egypt was the third-ranked producer of Direct-Reduced Iron (DRI) in the Middle east and North Africa region after Iran and Saudi Arabia and accounted for 5.4% of the world’s total output
The Egyptian steel industry represents one of the cornerstones of Egypt’s economic growth and development, due to its linkages to almost all other industries that stimulate economic expansion, such as construction, housing, infrastructure, consumer goods and automotive. All these industries rely heavily on steel industry and so, the importance and development of the steel sector is significant for the progress of the Egyptian economy in general.
The Egyptian market has many companies that produce different steel products.
This document provides the curriculum vitae of Prof. Dr. Hassan Zakaria Harraz. It details his personal and academic background, including his education, positions held, research interests, and publications. He is currently a professor of economic geology and ore resources at Tanta University in Egypt. The CV outlines his extensive experience in economic geology, mineral exploration, and research focused on gold deposits in Egypt. It also lists over 30 of his published papers on related topics.
Exploration in Deep Weathering Profiles, Supergene, R-mode factor analysis; Multi-element association geochemistry; Assessment of Au-Zn potentiality in Gossan; Rodruin-Egypt
Mineral Processing: Crusher and Crushing; Secondary and Tertiary Crushing Circuits; Types of Crusher; Types of Crushing; Types of Jaw Crushers; Impact Crusher; Types of Cone Crushers; Ball Mill; BEST STONE MANUFACTURERS; Local Quality and High quality ; International and Country/Hand made
Classification Equipment
Introduction; Chemical composition of garnet; Structure; Classification; Physical properties; Optical properties; Occurrences; Gem variety; and Uses
Garnet group of minerals is one of the important group of minerals.
Since they are found in wide variety of colours, they are also used as gemstones.
Garnet group of minerals are also abrasives and thus have various industrial applications.
Better Builder Magazine brings together premium product manufactures and leading builders to create better differentiated homes and buildings that use less energy, save water and reduce our impact on the environment. The magazine is published four times a year.
Online train ticket booking system project.pdfKamal Acharya
Rail transport is one of the important modes of transport in India. Now a days we
see that there are railways that are present for the long as well as short distance
travelling which makes the life of the people easier. When compared to other
means of transport, a railway is the cheapest means of transport. The maintenance
of the railway database also plays a major role in the smooth running of this
system. The Online Train Ticket Management System will help in reserving the
tickets of the railways to travel from a particular source to the destination.
1. Topic 6: CEMENT
Hassan Z. Harraz
hharraz2006@yahoo.com
2013- 2014
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement
2. OUTLINE OF TOPIC 6:
CEMENT
TYPES OF CEMENTS
PORTLAND CEMENT
TYPES OF PORTLAND CEMENT
GENERAL FEATURES OF THE MAIN TYPES OF PORTLAND CEMENT
ORDINARY PORTLAND CEMENT (OPC)
RAPID HARDENING PORTLAND CEMENT
SPECIAL TYPES OF RAPID HARDENING PORTLAND CEMENT
MANUFACTURE OF PORTLAND CEMENT:-
1) Raw Materials
2) Crushing & Grinding of Raw Materials
3)Type of cement processes:
a)Wet Process
b)Dry process
4) Burning Process
5) Grinding
6) storage, packing, dispatch
CEMENT CHEMISTRY
Chemical Compositions
Bogue’s Equations
Fineness of cement
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 2
3. CEMENT
DEFINATION:
Cement is the mixture of calcareous, siliceous, argillaceous and other substances.
Cement is a hydraulic binder and is defined as a finely ground inorganic material which, when mixed with
water, forms a paste which sets and hardens by means of hydration reactions and processes which, after
hardening retains it's strength and stability even under water.
Popular as building material.
Material with adhesive & cohesive properties.
To bind the fine & coarse aggregate together
To fill voids in between fine & coarse aggregate particle form a compact mass.
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 3
TYPES OF CEMENTS:
Cement may be hydraulic or non-hydraulic:
1)Non-hydraulic cements (e.g. gypsum plaster) must be kept dry
in order to retain their strength.
2)Hydraulic cements harden because of hydration, chemical
reactions that occur independently of the mixture's water content;
they can harden even underwater or when constantly exposed to
wet weather. The chemical reaction that results when the
anhydrous cement powder is mixed with water produces hydrates
that are not water-soluble. Hydraulic cement may be:
i) Portland cements
ii) Natural cements
iii) Expansive cements
iv) High-alumina cements
5. CEMENT
PORTLAND CEMENT
Made by mixing substances containing Calcium Carbonate such as chalk / limestone,
with substances containing silica , alumina and iron oxide such as clay/ shale.
•Clay/shale:
SiO2 Silica (silicon oxide) abbreviated S
Fe2O3 Ferrite (iron oxide) abbreviated F
Al2O3 Alumina (aluminium oxide) abbreviated A
•Limestone/chalk
CaCO3 Calcium carbonate abbreviated C
•then the mixture heated and became clinker.
•Clinker then grounded to powder.
•The hardening Portland cement is a chemical process during which heat is evolved.
Why is it called "portland" cement?
Joseph Aspdin, an English mason who patented the product in 1824, named it portland
cement because it produced a concrete that resembled the color of the natural limestone
quarried on the Isle of Portland, a peninsula in the English Channel
6. PORTLAND CEMENT
DEFINATION:
is a hydraulic cement that hardens in
water to form a water-resistant
compound.
The hydration products act as binder
to hold the aggregates together to form
concrete.
made by finely clinker produced by
calcining to incipient fusion a mixture of
argillaceous and calcareous materials:
Limestone + Shale/Clay + Heat = Clinker +CKD + Exit Gas
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 6
7. TYPES OF PORTLAND CEMENT
According to the ASTM standard, there are five basic types of Portland Cement:.
1) Regular cement, general use, called Ordinary Portland cement (OPC) – Type Ι
2) Moderate sulphate resistance, moderate heat of hydration, C3A < 7% , Modified cement -
Type ΙΙ
3) Rapid-hardening Portland cement , With increased amount of C3S, High early strength –
Type ΙΙΙ
4) Low heat Portland cement – Type ΙV
5) High Sulfate-resisting Portland cement – Type V
It is possible to add some additive to Portland cement to produce the following types:
Portland blastfurnace cement – Type ΙS
Pozzolanic cement - Type ΙP
Air-entrained cement - Type ΙA
White Portland Cement (WPC)
Colored Portland Cement
Note:
sulphates can react with C4ASH18 to from an expansive product. By reducing the C3A
content, there will be less C4ASH18 formed in the hardened paste.
Physically and chemically, these cement types differ primarily in their content of C3A and in
their fineness.
In terms of performance, they differ primarily in the rate of early hydration and in their ability
to resist sulfate attack.
• The general characteristics of these types are listed in Table 2.
• The oxide and mineral compositions of a typical Type I Portland cement were given in Tables.21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement
7
8. GENERAL FEATURES OF THE MAIN TYPES OF PORTLAND CEMENT
ASTM
Type Classification Characteristics Applications
Type I General purpose
Fairly high C3S content for
good early strength
development
General construction (most
buildings, bridges,
pavements, precast units,
etc)
Type II
Moderate sulfate
resistance (Modified
cement)
Low C3A content (<8%) Structures exposed to soil or
water containing sulfate ions
Type III High early strength
(Rapid-hardening)
Ground more finely, may have
slightly more C3S
Rapid construction, cold
weather concreting
Type IV Low heat of hydration
(slow reacting)
Low content of C3S (<50%)
and C3A
Massive structures such as
dams. Now rare.
Type V High sulfate
resistance Very low C3A content (<5%) Structures exposed to high
levels of sulfate ions
White White color No C4AF, low MgO Decorative (otherwise has
properties similar to Type I)
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 8
Chemical composition of
the main types of
Portland cement
9. RAPID HARDENING PORTLAND CEMENT
This type develops strength more rapidly than ordinary Portland cement. The initial strength is
higher , but they equalize at 2-3 months
Setting time for this type is similar for that of ordinary Portland cement
The rate of strength gain occur due to increase of C3S compound, and due to finer grinding of
the cement clinker ( the min. fineness is 3250 cm2/gm (according to IQS 5)
Rate of heat evolution is higher than in ordinary Portland cement due to the increase in C3S
and C3A, and due to its higher fineness
Chemical composition and soundness requirements are similar to that of ordinary Portland
cement
Uses
a)The uses of this cement is indicated where a rapid strength development is desired (to develop
high early strength, i.e. its 3 days strength equal that of 7 days ordinary Portland cement), for
example:
i) When formwork is to be removed for re-use
ii) Where sufficient strength for further construction is wanted as quickly as practicable, such
as concrete blocks manufacturing, sidewalks and the places that can not be closed for a
long time, and repair works needed to construct quickly.
b) For construction at low temperatures, to prevent the frost damage of the capillary water.
c) This type of cement does not use at mass concrete constructions.
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 9
10. SPECIAL TYPES OF RAPID HARDENING PORTLAND CEMENT
A) Ultra High Early Strength Cement
The rapid strength development of this type of cement is achieved by grinding the cement to a very high
fineness: 7000 to 9000 cm2/g. Because of this, the gypsum content has to be higher (4 percent expressed as
SO3). Because of its high fineness, it has a low bulk density. High fineness leads to rapid hydration, and
therefore to a high rate of heat generation at early ages and to a rapid strength development ( 7 days strength of
rapid hardening Portland cement can be reached at 24 hours when using this type of cement). There is little
gain in strength beyond 28 days.
It is used in structures where early prestressing or putting in service is of importance.
This type of cement contains no integral admixtures.
B) Extra Rapid Hardening Portland Cement
This type prepare by grinding CaCl2 with rapid hardening Portland cement. The percentage of CaCl2 should not
be more than 2% by weight of the rapid hardening Portland cement.
By using CaCl2:
The rate of setting and hardening increase (the mixture is preferred to be casted within 20 minutes).
The rate of heat evolution increase in comparison with rapid hardening Portland cement, so it is more
convenient to be use at cold weather.
The early strength is higher than for rapid hardening Portland cement, but their strength is equal at 90 days.
Because CaCl2 is a material that takes the moisture from the atmosphere, care should be taken to store this
cement at dry place and for a storage period not more than one month so as it does not deteriorate.
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 10
11. MANUFACTURING OF CEMENT
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 11
1) Quarry
2) Raw Material
3) Mixing and crushing of raw
materials:
a) Dry process
b) Wet process
4) Burning
5) Grinding
6) Storage
7) Packing
8) Dispatch
12. Step in the Manufacture of Portland Cement
1. BLASTING : The raw materials that are used to manufacture cement (mainly limestone and clay) are blasted from the quarry.
Quarry face
1. BLASTING 2. TRANSPORT
quarry
3. CRUSHING & TRANSPORTATION
2. TRANSPORT : The raw materials are loaded into a dumper.
crushing
conveyor
dumper
storage at
the plant
loader
Typical Quarry operation:
Typically shale provides the argillaceous components: Silica (SiO2, Aluminum (Al2O3) & Iron (Fe2O3)
Limestone provides the calcareous component: Calcium Carbonate (CaCO3 )
Raw materials may vary in both composition and morphology.
13. THE CEMENT MANUFACTURING PROCESS
1. RAW GRINDING : The raw materials are very finely ground in order to produce the raw mix.
1. RAW GRINDING
Raw grinding and burning
2. BURNING
2. BURNING : The raw mix is preheated before it goes into the kiln, which is heated by a flame that can
be as hot as 2000 °C. The raw mix burns at 1500 °C producing clinker which, when it leaves the kiln, is
rapidly cooled with air fans. So, the raw mix is burnt to produce clinker : the basic material needed to
make cement.
conveyor
Raw mix
kiln
cooling
preheating
clinker
storage at
the plant
Raw mill
14. MANUFACTURE OF ORDINARY PORTLAND CEMENT
Ordinary Portland Cement (OPC) is one of several types of cement being manufactured throughout the
world.
OPC consists mainly of lime (CaO), silica (SiO2) , alumina (Al2O3) , iron (Fe2O3) and sulphur trioxide
(SO3). Magnesium (MgO) and other Oxide elements are present in small quantities as an impurity
associated with raw materials.
When cement raw materials containing the proper proportions of the essential oxides are ground to a
suitable fineness and then burnt to incipient fusion in a kiln, chemical combination takes place, largely
in the solid state resulting in a product named clinker.
This clinker, when ground to a suitable fineness, together with a small quantity of gypsum (SO3) is
Portland Cement. SO3 is added at the grinding stage to retard the setting time of the finished cement.
Basic Chemical Components of Portland Cement:
Calcium (Ca)
Silicon (Si)
Aluminum (Al)
Iron (Fe)
Typical Raw Materials:
Limestone (CaCO3)
Sand (SiO2)
Shale, Clay (SiO2, Al2O3, Fe2O3)
Iron Ore/Mill Scale (Fe2O3)
2/3 calcareous materials (lime bearing) - limestone
1/3 argillaceous materials (silica, alumina, iron)- clay
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 14
15. 2) Raw Materials for Cement Manufacture
The first step in the manufacture of Portland Cement is to combine a variety of raw ingredients so that
the resulting cement will have the desired chemical composition.
These ingredients are ground into small particles to make them more reactive, blended together, and
then the resulting raw mix is fed into a cement kiln which heats them to extremely high temperatures.
Since the final composition and properties of Portland Cement are specified within rather strict bounds,
it might be supposed that the requirements for the raw mix would be similarly strict. As it turns out,
this is not the case. While it is important to have the correct proportions of calcium, silicon, aluminum,
and iron, the overall chemical composition and structure of the individual raw ingredients can vary
considerably. The reason for this is that at the very high temperatures in the kiln, many chemical
components in the raw ingredients are burned off and replaced with oxygen from the air.
Table 1 lists just some of the many possible raw ingredients that can be used to provide each of the
main cement elements.
Table 1: Examples of raw materials for Portland Cement manufacture
Calcium Silicon Aluminum Iron
Limestone Clay Clay Clay
Marl Marl Shale Iron ore
Calcite Sand Fly ash Mill scale
Gypsum Shale Aluminum ore
refuse
Shale
Marly limestone Fly ash Phyllite Blast furnace
dust
Sea Shells Rice hull
ash
slate slag
Cement kiln dust Silica
Chalk Sand
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 15
16. Typical Composition of Raw Materials
21 November
Prof. Dr. H.Z. Harraz Presentation Cement 16
17. 2) Crushing & Grinding of Raw Materials
Due to the variable nature of these components, they are pre-blended prior to their use.
It is crushed and stored in a pre-blending hall, utilizing the chevron pile stacking
method. In this method, stacking takes place at one end of the pile. At the other end of
the pile the material is reclaimed and then stored in a feeding hopper which is ready for
use.
The limestone is crushed to less than 25mm in size.
Grinding and blending prior to entering the kiln can be performed with the raw
ingredients in the form of a slurry (the wet process) or in dry form (the dry process). The
addition of water facilitates grinding. However, the water must then be removed by
evaporation as the first step in the burning process, which requires additional energy.
The wet process, which was once standard, has now been rendered obsolete by the
development of efficient dry grinding equipment, and all modern cement plants use the
dry process. When it is ready to enter the kiln, the dry raw mix has 85% of the particles
less than 90 µm in size
21 November
Prof. Dr. H.Z. Harraz Presentation Cement 17
18. Mixing and crushing of raw materials: Actually the purpose of both processes is to
change the raw materials to fine powder.
Dry process Wet process
This process is usually used when raw
materials are very strong and hard.
This process is generally used when raw materials are
soft because complete mixing is not possible unless
water is added.
In this process, the raw materials are
changed to powdered form in the absence
of water.
In this process, the raw materials are changed to
powdered form in the presence of water
Dehydration zone requires a somewhat
shorter distance than wet process.
Dehydration zone would require up to half the length of
the kiln easiest to control chemistry & better for moist
raw materials
74% of cement produced. 26% of cement produced
kilns less fuel requirements High fuel requirements - fuel needed to evaporate
30+% slurry water- The kiln is a continuous stream
process vessel in which feed and fuel are held in
dynamic balance
In this process calcareous material such
as lime stone (calcium carbonate) and
argillaceous material such as clay are
ground separately to fine powder in the
absence of water and then are mixed
together in the desired proportions.
Water is then added to it for getting thick
paste and then its cakes are formed, dried
and burnt in kilns.
In this process, raw materials are pulverized by using a
Ball mill, which is a rotary steel cylinder with hardened
steel balls. When the mill rotates, steel balls pulverize
the raw materials which form slurry (liquid mixture). The
slurry is then passed into storage tanks, where correct
proportioning is done. Proper composition of raw
materials can be ensured by using wet process than dry
process. Corrected slurry is then fed into rotary kiln for
burning.
19. 3) Burning in a Kiln – Formation of Cement Clinker
The next step in the process is to heat the blended mixture of raw ingredients (the
raw mix) to convert it into a granular material called cement clinker.
This requires maximum temperatures that are high enough to partially melt the raw
mix. Because the raw ingredients are not completely melted, the mix must be
agitated to ensure that the clinker forms with a uniform composition.
This is accomplished by using a long cylindrical kiln that slopes downward and rotates
slowly.
To heat the kiln, a mixture of fuel and air is injected into the kiln and burned at the
bottom end. The hot gases travel up the kiln to the top, through a dust collector, and
out a smokestack. A variety of fuels can be used, including pulverized coal or coke,
natural gas, lignite, and fuel oil. These fuels create varying types and amounts of ash,
which tend to have compositions similar to some of the aluminosilicate ingredients in
the raw mix. Since the ash combines with the raw mix inside the kiln, this must be
taken into account in order to correctly predict the cement compassion. There is also
an increasing trend to use waste products as part of the fuel, for example old tires. In
the best-case scenario, this saves money on fuel, reduces CO2 emissions, and
provides a safe method of disposal.
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 19
20. Clinker Burning
For the production of cement clinker, the raw meal which is known as
kiln feed at this stage has to be heated to a temperature of about
1550 oC in the long cylindrical rotating kiln.
The kiln feed enters the system at the top of the pre-heater and fall
until the lower end of the kiln.
The heat exchange occurs during this process when the hot gases
from the kiln end rise up to the top of the pre-heater.
The clinker formation process is divided into four parts: drying,
calcining, sintering and cooling.
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 20
And the Hottest
21. The raw materials used for manufacturing Portland Cement are limestone, clay and
Iron ore.
a) Limestone (CaCO3) is mainly providing calcium in the form of calcium oxide
(CaO)
CaCO3 (1000oC) → CaO + CO2
b) Clay is mainly providing silicates (SiO2) together with small amounts of Al2O3 +
Fe2O3
Clay (1450oC) → SiO2 + Al2O3 + Fe2O3 + H2O
c) Iron ore and Bauxite are providing additional aluminum and iron oxide (Fe2O3)
which help the formation of calcium silicates at low temperature. They are
incorporated into the raw mix.
d) The clinker is pulverized to small sizes (< 75 μm). 3-5% of gypsum (calcium sulphate)
is added to control setting and hardening.
The majority particle size of cement is from 2 to 50 μm.
(Note: “Blaine” refers to a test to measure particle size in terms of surface area/mass)
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 21
22. Kiln Process Thermochemical Reactions
Kiln Process
Process Temperature (oC) Reactions Chemical Transformation
Drying 20 - <100 Escape of free water (i.e., Free
Water evaporates)
Pre-heat
100 - 300 Escape of adsorbed water (i.e.,
Crystallization water driven out)
400 - 750 Chemical water driven out,
Decomposition of shale., with
formation of metakaolinite
Al4Si4O10(OH)8
2(Al2O3.2SiO2) + 4H2O
600 - 900 Decomposition of metakaolinite and
other compounds, with formation of
reactive oxide mixture
Al2O3.2SiO2 Al2O3.+ 2SiO2
Calcining 600 - 1000 Decomposition of limestone, CO2
Driven out, Formation of Free lime ,
with formation of CS (CaO.SiO2) and
CA (CaO.Al2O3)
3CaCO3 3CaO + 3CO2
3CaO + 2SiO2 + Al2O3
2(CaO.SiO2) + CaO.Al2O3
Sintering
Clinkering
800 – 1550 (1350
exothermic)
Uptake of lime by CS and CA,
Formation of Liquid Phase,
Formation of: Belite (C2S),
Aluminates (C3A) and Ferrites (C4AF)
CS + C C2S
2C + S C2S
CA + 2C C3A
CA + 3C + F C4AF
Cooling
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 22
24. Burning Process
Kiln is typically about 180 m long and 6 m in diameter, has a downward slope of 3-4%,
and rotates at 1-2 revolutions per minute.
The raw mix enters at the upper end of the kiln and slowly works its way downward to
the hottest area at the bottom over a period of 60-90 minutes, undergoing several
different reactions as the temperature increases. It is important that the mix move
slowly enough to allow each reaction to be completed at the appropriate temperature.
Because the initial reactions are endothermic (energy absorbing), it is difficult to heat the
mix up to a higher temperature until a given reaction is complete.
The general reaction zones are as follows:
1) Dehydration zone (up to ~ 450˚C)
2) Calcination zone (>450˚C – 900˚C)
3) Solid-state reaction zone (>900˚ - 1300˚C)
4) Clinkering zone (>1300˚C – 1550˚C)
5) Cooling zone
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 24
25. i) Generalized Diagram of a Long Dry Process Kiln
Reaction
Material
Temperature
Gas
Temperature
The kiln exit gas
temperature will
depend on the
process
Zone
Exhaust
GasesRaw
Feed
Clinker Out
26. Reaction Zone Temperature (oC) Characteristics
Dehydration up to ~ 450
This is simply the evaporation and removal of the free water
Even in the “dry process” there is some adsorbed moisture in the raw mix.
Although the temperatures required to do this are not high, this requires significant time and
energy.
In the wet process, the dehydration zone would require up to half the length of the kiln, while
the dry process requires a somewhat shorter distance.
Calcination 450˚C – 900
The term calcination refers to the process of decomposing a solid material so that one of its
constituents is driven off as a gas.
At about 600˚C the bound water is driven out of the clays,
and by 900˚C the calcium carbonate is decomposed, releasing carbon dioxide.
By the end of the calcination zone, the mix consists of oxides of the four main elements which
are ready to undergo further reaction into cement minerals.
Because calcination does not involve melting, the mix is still a free-flowing powder at this
point.
Solid-state
reaction
>900˚ - 1300
This zone slightly overlaps, and is sometimes included with, the calcination zone.
As the temperature continues to increase above ~ 900˚C there is still no melting, but solid-
state reactions begin to occur.
CaO and reactive silica combine to form small crystals of C2S (dicalcium silicate; Belite), one of
the four main cement minerals.
In addition, intermediate calcium aluminates (C3A) and calcium ferrite (C4AF) compounds form.
These play an important role in the clinkering process as fluxing agents, in that they melt at a
relatively low temperature of ~1300˚C, allowing a significant increase in the rate of reaction.
Without these fluxing agents, the formation of the calcium silicate cement minerals would be
slow and difficult.
In fact, the formation of fluxing agents is the primary reason that Portland (calcium silicate)
Cements contain aluminum and iron at all.
The final aluminum- and iron-containing cement minerals (C3A and C4AF) in a Portland Cement
contribute little to the final properties.
As the mix passes through solid-state reaction zone it becomes “sticky” due to the tendency
Burning Process (Cont.)
27. Reaction Zone Temperature (oC) Characteristics
Clinkering >1300 – 1550
This is the hottest zone where the formation of the most important cement mineral, Alite
(C3S), occurs.
The zone begins as soon as the intermediate calcium aluminate (C3A) and ferrite (C4AF) phases
melt.
The presence of the melt phase causes the mix to agglomerate into relatively large nodules
about the size of marbles consisting of many small solid particles bound together by a thin
layer of liquid.
Inside the liquid phase, Alite (C3S) forms by reaction between Belite (C2S) crystals and CaO.
(C2S + C C3S)
Crystals of solid Alite (C3S) grow within the liquid, while crystals of Belite (C2S) formed earlier
decrease in number but grow in size.
The clinkering process is complete when all of silica is in the C3S and C2S crystals and the
amount of free lime (CaO) is reduced to a minimal level (<1%).
Cooling
As the clinker moves past the bottom of the kiln the temperature drops rapidly and the liquid
phase solidifies, forming the other two cement minerals C3A (aluminate) and C4AF (ferrite).
In addition, alkalis (primarily K) and sulfate dissolved in the liquid combine to form K2SO4 and
Na2SO4.
The nodules formed in the clinkering zone are now hard, and the resulting product is called
cement clinker.
The rate of cooling from the maximum temperature down to about 1100˚C is important, with
rapid cooling giving a more reactive cement.
This occurs because in this temperature range the C3S can decompose back into C2S and CaO,
among other reasons.
It is thus typical to blow air or spray water onto the clinker to cool it more rapidly as it exits the
kiln.
Rapid cooling of the clinker is essential as this hampers the formation of crystals, causing
part of the liquid phase to solidify as glass.
The faster the clinker cooling the smaller the crystals will be when emerging from the liquid
phase.
28.
29. Suspension Preheaters and Calciners
The chemical reactions that occur in the dehydration and calcination zones are
endothermic, meaning that a continuous input of energy to each of the particles
of the raw mix is required to complete the reaction. When the raw mix is piled up
inside a standard rotary kiln, the rate of reaction is limited by the rate at which
heat can be transferred into a large mass of particles. To make this process more
efficient, suspension preheaters are used in modern cement plants to replace the
cooler upper end of the rotary kiln. Raw mix is fed in at the top, while hot gas
from the kiln heater enters at the bottom. As the hot gas moves upward it creates
circulating “cyclones” that separate the mix particles as they settle down from
above. This greatly increases the rate of heating, allowing individual particles of
raw mix to be dehydrated and partially calcined within a period of less than a
minute.
Alternatively, some of the fuel can be burned directly within the preheater to
provide even more heating to the suspended particles. The area of the preheater
where fuel is burned is called a precalciner. With a precalciner, the particles are
nearly completely calcined as they enter the rotary kiln. Preheaters and
precalciners save on fuel and increase the rate at which the mix can be moved
through the rotary kiln.
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 29
31. 4) Grinding and the Addition of Gypsum
Now the final process is applied which is grinding of clinker, it is first cooled down to atmospheric temperature.
Grinding of clinker is done in large tube mills.
After proper grinding gypsum (Calcium sulphate CaSO4) in the ratio of 01-04 % is added for controlling the
setting time of cement.
Finally, fine ground cement is stored in storage tanks from where it is drawn for packing.
Once the nodules of cement clinker have cooled, they are ground back into a fine powder in a large grinding mill.
At the same time, a small amount of calcium sulfate such as gypsum (calcium sulfate) is blended into the
cement. The calcium sulfate is added to control the rate of early reaction of the cement
Cement is produced by grinding clinker with gypsum (calcium sulfate) in the finish-grinding mill to a required
fineness.
A small quantity of gypsum, about 3 to 5 %, is needed to control the setting time of cement produced.
The amount of gypsum being used is determined by the Sulphuric anhydride (SO3) contents in cement.
Cement Grinding
32. Cement Storage & Distribution
• At this point the manufacturing process is complete and the
cement is ready to be bagged or transported in bulk away
from the plant After the grinding process, cement is
pumped into the storage silos.
• This silo is preventing the moisture to react with cement.
• When needed cement from the silos is packed into bags or
loaded into road tankers and rail wagons for dispatch.
• However, the cement is normally stored in large silos at the
cement plant for a while so that various batches of cement
can be blended together to even out small variations in
composition that occur over time.
21 November
Prof. Dr. H.Z. Harraz Presentation Cement 32
33. CHEMICAL COMPOSITIONS
Oxide Notation
CaO C
SiO2 S
Al2O3 A
Fe2O3 F
SO3
H2O H
MgO M
Na2O N
S
The properties of cement
during hydration vary
according to:
Chemical composition
Degree of fineness
It is possible to manufacture
different types of cement by
changing the percentages of
their raw materials.
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 33
1) Cement chemistry notation based on oxides
CEMENT CHEMISTRY
34. Chemical Name Chemical
Formula
Oxide Formula Cement
Notation
Mineral Name
Tricalcium Silicate Ca3SiO5 3CaO.SiO2 C3S(40-60%) Alite
Dicalcium Silicate Ca2SiO4 2CaO.SiO2 C2S(16-30%) Belite
Tricalcium Aluminate Ca3Al2O6 3CaO.Al2O3 C3A(7-15%) Aluminate
Tetracalcium
Aluminoferrite
Ca2AlFeO5 4CaO.Al2O3.Fe2O3 C4AF(7-12%) Ferrite
Calcium hydroxide Ca(OH)2 CaO.H2O CH Portlandite
Calcium sulfate
dihydrate
CaSO4.2H2O CaO.SO3.2H2O CSH2 Gypsum
Calcium oxide CaO CaO C Lime
Compound Composition of
Clinker / Cement
21 November
Prof. Dr. H.Z. Harraz Presentation Cement 34
35. Phase Diagram
Tricalcium Silicate Tricalcium Aluminate
SiO2
CaO
CaOCaO
CaO
Al2O3
CaOCaO
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 35
36. Bogue’s Equations – Compound composition
To calculate the amounts of C3S, C2S, C3A, and C4AF in clinker (or the
cement) from its chemical analysis (from the mill certificate)
Assumptions in calculations:
Chemical equilibrium established at the clinkering temperature
Components maintained unchanged through the rapid cooling
period
Compounds are “pure”
• A simple estimate of the phase composition of a Portland Cement can be
obtained from the oxide composition if one assumes that the four main
cement minerals occur in their pure form.
• With this assumption, all of the Fe2O3 is assigned to C4AF and the
remaining Al2O3 is assigned to C3A.
• This leaves a set of two linear equations to be solved for the amounts of
C2S and C3S.
• This method is named after the cement chemist R.H. Bogue. A
standardized version of this simple method is given in ASTM C 150. There
are two sets of equations, based on the ratio of A/F in the cement (both
inputs and outputs are in weight percent):
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 36
38. Types of Cement
Depending upon our requirements i.e. using it at a suitable place, we use
different types of cement.
Ordinary Portland Cement
Rapid Hardening or High early strength Cement
Sulphate Resisting Cement
Quick setting Cement
High Alumina Cement
Portland Slag Cement
Low Heat Cement
Air Entraining Cement
White Cement
Coloured Cement
Portland Pozzolona Cement
39. Ordinary Portland Cement:
It is the variety of artificial cement.
It is called Portland cement because on hardening (setting) its colour resembles
to rocks near Portland in England. It was first of all introduced in 1824 by
Joseph Asp din, a bricklayer of Leeds, England.
Chemical Composition of O.P. Cement:
O.P.C has the following approximate chemical composition:
The major constituents are:
1. Lime (CaO) 60- 63%
2. Silica (SiO2) 17- 25%
3. Alumina (Al2O3) 3- 8%
The auxiliary constituents are:
1.Iron oxide (Fe2O3) 0.5- 6%
2.Magnesia (MgO) 1.5- 3%
3.Sulphur Tri Oxide (SO3) 1- 2%
4.Gypsum 1 to 4%
40. Functions of Cement Manufacturing Constituent
(i) Lime (CaO):
Lime forms nearly two-third (2/3) of the cement. Therefore sufficient quantity of the lime must
be in the raw materials for the manufacturing of cement. Its proportion has an important
effect on the cement. Sufficient quantity of lime forms di-calcium silicate (Ca2SiO2) and tri-
calcium silicate in the manufacturing of cement.
Lime in excess, causes the cement to expand and disintegrate.
(ii) Silica (SiO2):
The quantity of silica should be enough to form di-calcium silicate (Ca2SiO2) and tri-calcium
silicate in the manufacturing of cement. Silica gives strength to the cement. Silica in excess
causes the cement to set slowly.
(iii) Alumina (Al2O3):
Alumina supports to set quickly to the cement. It also lowers the clinkering temperature.
Alumina in excess, reduces the strength of the cement.
(iv) Iron Oxide (Fe2O3):
Iron oxide gives colour to the cement.
(v) Magnesia (MgO):
It also helps in giving colour to the cement.
Magnesium in excess makes the cement unsound.
(vi) Calcium Sulphate (CaSO4) (or) Gypsum (CaSO4 . 2H2O) :
At the final stage of manufacturing, gypsum is added to increase the setting of cement.
41. Rapid Hardening Cement (or) High Early Strength cement
This type cement gets the strength faster than OPC, However its Initial and Final setting is same as those
of OPC. It contains more of Tri-Calcium Silicate and is more finely grounded. It gives out more Heat while
setting so it is as such unsuitable for massive concrete. It is Used for the Structures which are Subjected
to loads early e.g. Roads, Bridges.
This cement contains more % age of C3S and less % of C2S.
This is in fact high early strength cement. The high strength at early stage is due to
finer grinding, burning at higher temperature and increased lime content. The strength
obtained by this cement in 4 days is same as obtained by O.P.C in 14 days.
This cement is used in highway slabs which are to be opened for traffic quickly. This is
also suitable for use in cold weather areas.
One type of this cement is manufactured by adding calcium chloride (CaCl2) to the
O.P.C in small proportions. Calcium chloride (CaCl2) should not be more than 2%.
When this type of cement is used, shuttering material can be removed earlier.
Quick Setting cement
It sets faster than the Ordinary Portland Cement.
When concrete is to be laid under water, quick setting cement is to used.
This cement is manufactured by adding small % of aluminum sulphate (Al2SO4) which accelerates the
setting action.
The setting action of such cement starts with in 5 minutes after addition of water and it becomes stone
hard in less than half an hour.
It is required for making concrete that is required to set early as for lying under water or in running water.
Initial setting being very little there is always the danger of concrete having undergone its initial setting.
Thus this type of cement is used in more special cases.
42. High Alumina Cement
It is manufactured by the burning of bauxite ore and lime stone in correct proportions and at high temperature.
The resulting product is then ground finely.
It develops Strength Rapidly.
It is of black colour and resists well the attack of chemicals especially of sulphates and sea water.
Its ultimate strength is much higher than OPC.
Its initial setting takes more than 2 hours and the final set takes place immediately thereafter.
Most of the heat it gives in the first 10 hrs as a result it can be conveniently used in freezing temperatures.
At ordinary temperature it is used in thin layers.
This cement contains high aluminate % usually between 35-55%.
It gains strength very rapidly with in 24 hours.
It is also used for construction of dams and other heavy structures.
It has resistance to sulphates and action of frost also.
Portland Slag Cement
It is obtained by mixing clinker, gypsum and granulated slag in a proper proportion.
The Properties of this cement is very similar to that of OPC which are as under.
It has lesser heat of hydration and has better resistance of soils, sulphates of alkali metals, alumina and iron.
It has better resistance to acidic water.
This type of cement is mostly used in Marine Works.
Low Heat Cement
The Heat Generated by cement while setting may cause the structure to crack in case of concrete. This Heat
generation is controlled by keeping the percentage of Tri-calcium silicate and that of Tri-calcium aluminate (C3 A) low.
In this cement the heat of hydration is reduced by tri-calcium aluminate (C3 A) content.
It contains less % of lime than ordinary port land cement.
It is used for mass concrete works such as dams …etc.
Its initial setting and Final setting times are nearly the same as those of OPC. It is not very suitable for
Ordinary structures because the use of cement will delayed time of drying. It will also need more curing.
43. Air Entraining Cement
This type of cement was first of all developed in U.S.A to produce such concrete which would have resistance
to weathering actions and particularly to the action of frost.
It is the OPC mixed with some air entraining agents.
Natural resins, fats, oils and fatty acids ….etc are common used as air entraining agents.
These materials have the property of entraining air in the form of fine air bubbles. The bubbles render the
concrete to become more plastic, workable and more resistant to freezing. However because of air
entrainment the strength of concrete reduces and as such the quantity of air so entrained should not exceed
5%.
It is found that entrainment of air or gas bubbles while applying cement, increases resistance to frost action.
Air entraining cement is produced by grinding minute air entraining materials with clinker or the materials are
also added separately while making concrete.
Entrainment of air also improves workability and durability. It is recommended that air contents should be 3- 4
% by volume.
White Cement
This cement is called snowcrete.
It is the cement of pure white colour and having same properties as those of Ordinary Portland
Cement(Greyish colour of cement is due to iron oxide (FeO)).
As iron oxide gives the grey colour to cement, it is therefore necessary for white cement to keep the content of
iron oxide as low as possible.
White cement is manufactured from chalk or limestone and China clay free from Iron Oxide are suitable for its
manufacturing.
Oil fuel and not the coal is used for the burning of this cement.
It is much more costly than ordinary cement.
This cement is costlier than O.P.C.
It is mainly used for architectural finishing in the buildings.
.
44. Sulphate Resisting Cement:
It is modified form of O.P.C and is specially manufactured to resist
the sulphates.
In certain regions/areas where water and soil may have alkaline
contents and O.P.C is liable to disintegrate, because of unfavourable
chemical reaction between cement and water, S.R.C is used.
This cement contains a low % of C3A not more than 5%.
This cement requires longer period of curing.
This cement is used for hydraulic structures in alkaline water and for
canal and water courses lining.
It develops strength slowly, but ultimately it is as strong as O.P.C.
45. Coloured Cement
Various coloured cement are prepared when required in special
cases. Suitable pigments are added with OPC to get red or brown
cement but for other colours 5 – 10% of desired pigments are
grounded with white cement. Pigments used should be chemically
inert and also durable so as they must not fade due to the effect of
lights sun or weather.
Portland Pozzolona Cement
Portland Pozzolona cement is produced by grinding together
Portland cement and Pozzolona. This cement has properties similar
to those of OPC and can therefore be used for all general purpose.
Portland Pozzolona cement produces less heat of hydration and
offers greater resistance to attack of aggressive water or sulphates
bearing than OPC. Portland Pozzolona cement are particularly used
in marine works. It takes a little longer to gain strength. Ultimate
Strength of this cement is more than OPC
46. HYDRATION
It's a process of chemical reaction between
cement and water.
It results first in setting (the concrete become
solid) and then hardening (increase of
strength and stiffness).
Heat is liberated during hydration process.
Thus, during the hardening process, the
concrete is being continually warmed by
internal heat generated
47. WHAT IS SETTING ?
When cement is mixed with sufficient water, within 1 or 2 hr after the mixing, the
sticky paste losses its fluidity ; within a few hours after mixing, noticeable
stiffening commences.
Setting can be divided to 2 stage that is:
a) Initial Set
b) Final Set
Initial set is when the paste begin to stiffen
Final set is when the paste beginning to harden and able to sustain some loads.
Initial Setting Time is the time lapse from the addition of water in the mix to the
initial set.
Initial Setting Time and Final Setting Time can be determine by using Vicat
Apparatus in laboratory.
They are measure at lab. As the time required for the cement paste to withstand
a certain arbitrary pressure.
The time taken for a 1-mm diameter needle in the Vicat apparatus to penetrate a
depth of 25mm into the cement past sample is the initial setting time.
The final setting time is reached when in the modified Vicat apparatus only the
needle penetrates the surface, while the attachment fails to do so.
The rate of setting is also a measure of the rate of heat of hydration.
51. Consistency Test
• It is used to determine the % of water required for preparing cement pastes for
other tests
Procedure:
1. Take 300g cement, add 30% or 90g of water
2. Mix water and cement on a non-porous surface. Mixing should be done.
• Fill the mould of Vicat apparatus.
• The interval between the addition of water to the commencement of filling the
moulds is known as the time of gauging.
Among the factors affect the setting time are:
a) Fineness of cement
b) Chemical composition
c) Amount of water
Gypsum added to clinker to retard setting and prevent flash set.
Flash set is defined as the rapid development of permanent rigidity of the cement
paste along with high heat.
False set is the rapid development of rigidity without the evolution of heat .
52.
53. Compressive strength
• Mortar of cement & sand is prepared, 1:3.
• Water is added, water cement ratio 0.4:1
• It is placed in moulds & form cubes of sides 70.6 or 76 mm.
• The cement required is 185 or 235g
• Compacted in vibrating machine in 2 min.
• Moulds placed in damp cabin for 24 hrs
• Specimens are removed & placed in water for curing.
• It is tested in compressive testing machine after 3 and 7 days.
• Every side is calculated and average is taken.
• For 3 days: > 115 kg/cm2 or 11.5 N/mm2
• for 7 days: > 175 kg/cm2 or 17.5 N/mm2
54. Tensile Strength
• Procedure:
1. Mortar is prepared cement(1) : Sand (3)
2. Water is added 8%
3. Mortar is placed in briquette moulds
55.
56.
57. • Typical briquette is formed.
• A small heap is formed at its top.
• It is beaten down by a standard spatula till water appears on
the surface.
• Same procedure is repeated for other sides of briquettes.
• 12 standard briquettes are prepared
• The quantity of cement may be 600g for 12 briquettes
• It is kept in damp cabin for 24 hrs.
• It is carefully removed from mould and submerged in clean
water for curing.
• It is tested in testing machine after 3 and 7 days
• The cross section of briquettes at least section is 6.45 cm2
• Ultimate tensile stress = failing load
6.45
58. • After 3 days: > 20 kg/cm2
• After 7 days: > 25 kg/cm2
59. HARDENING
Hardening is the development of strength over an extended period of time, is
completed for months or years.
Hydration is the key for strength development in concrete.
Hydration process are gradual and require continuous presence of water.
Adding water to the cement would cause temperature of the mixture rise rapidly
due to reaction between Tricalcium Aluminate and water that is initially quite
rapid.
This is because of since it takes some time for the gypsum to dissolve
sufficiently to control the reaction of Tricalcium Aluminate.
Gypsum prevents flash setting that happen due to the reaction of Tricalcium
Aluminate.
Thereafter, setting and gradual hardening take place by the reaction of
Tricalcium Silicate
and Dicalcium Silicate with water.
Atmosphere doesn't take part in hydration process
Hydration process can't take place completely without enough water in the
mixture.
Hydration rate depends surface area of clinker expose and fineness of grinding.
Rate of hydration decreases continuously with age as the resistance to water
penetration of unhydrated cement grains progressively rises.
61. Colour should be uniform
Typical cement colour (gray colour
with light greenish shade)
It gives an indication of excess of
lime or clay and the degree of
burning.
62. Physical properties
Feel smooth when touched or rubbed in between
fingers.
If felt rough, indicates adulteration with sand.
If hand is inserted in cement bag, hand feels cool
and not warm.
If it immersed in water, it should sink and should
not float
A paste of cement feel sticky
If it contains clay & silt as adulterant, it give
earthy smell.
63. Presence of Lumps
•It should free from hard lumps.
•It is due to the absorption of moisture
from atmosphere.
•If a bag contains lumps it should be
rejected.
64. Strength
• It is tested by three methods:
1. Briquettes with a lean or weak mortar are made (75mm x
25mm x 12mm).
The proportion of cement & sand is 1:6.
Immersed in water for 3 days.
• If cement is good it will not be broken easily and difficult to
convert powder form.
2. A block is prepared (25 x 25 x 200) and immersed in water for
7 days.
• Then it is placed on supports 150 mm apart and loaded
340N.
• It should not show signs of failure.
3. Thick paste of cement with water is made on thick glass and
kept in water for 24 hours.
• It should set and not crack
65. TO CHECK THE QUALITY OF CEMENT IN THE FILED:
1) Colour greenish grey.
2) One feels cool by thrusting one’s hand in the cement bag.
3) It is smooth when rubbed in between fingers.
4) A handful of cement thrown in a bucket of water should float.
QUALITY TESTS OF CEMENT:
1) Fineness Test,
2) Consistency test / setting time test
3) Setting Time Test
4) Compressive strength test
66. Fineness of cement
• Grinding is the last step in
processing
• Measures of fineness
Specific surface
Particle size
distribution
• Blaine’s fineness
Measure of air
permeability
• Typical surface areas
350m2 / kg (Normal
cements)
~ 500 m2 / kg (High early
strength cements)
Significance of fineness
Finer cement = Faster reaction
Finer cement = Higher heat of
hydration
Large particles do not react
with water completely
Higher fineness
Higher shrinkage
Reduced bleeding
Reduced durability
More gypsum needed
21 November 2015 Prof. Dr. H.Z. Harraz Presentation Cement 66
67. (1) Fineness Test:
Finer cements react quicker with water and develop early strength,
though the ultimate strength is not affected. However finer cements
increase the shrinkage and cracking of concrete. The fineness is
tested by:
By Sieve analysis:
Break with hands any lumps present in 100 grams of cement placed
in IS sieve No.9 and sieve it by gentle motion of the wrist for 15
minutes continuously.
The residue when weighed should not exceed 10 percent by weight
of the cement sample.
68. (2) Consistency Test /Setting Time Test :
This test is performed to determine the quantity of water required
to produce a cement paste of standard or normal consistency.
Standard consistency of cement paste may be defined as the
consistency which permits the Vicate’s plunger (10 mm, 40 to 50
mm in length) to penetrate to a point 5 mm to 7 mm from the
bottom ( or 35 mm to 33 mm from top) of Vicat mould.
When the cement paste is tested within the gauging time ( 3 to 5
minutes) after the cement is thoroughly mixed with water.
Vicat apparatus is used for performing this test.
69. (3) Setting Time Test:
In cement hardening process, two instants are very important, i.e.
initial setting and final setting.
a) Initial Setting Time:
The process elapsing between the time when water is added to the
cement and the time at which the needle ( 1 mm square or 1.13 mm
dia., 50 mm in length) fails to pierce the test block ( 80 mm dia. and
40 mm high) by ~5 mm, is known as Initial Setting Time of Cement.
b) Final Setting Time:
The process elapsing between the time when water is added to the
cement and the time at which a needle used for testing final setting
upon applying gently to the surface of the test block, makes an
impression thereon, while the attachment of the needle fails to do so,
is known as final Setting Time of Cement.
70. (4) Compressive Strength test of Cement:
This test is very important. In this test, three moulds of (face area
50 cm2) are prepared and cured under standard temperature
conditions and each cube tested by placing it between movable
jaws of the compressive strength testing machine. The rate of
increasing load is zero in the beginning and varies at 350 kg/cm2
per minute. The load at which the cube gets fractured divided by
the cross sectional area of the cube, is the compressive strength of
the cube. The average of the compressive strengths of three cubes
is the required compressive strength of the cement sample.