The document discusses the use of fly ash from coal combustion in power plants. It provides background on fly ash, including its composition, classification into Class F and Class C ashes, and various applications. Some key applications discussed are: use in concrete where fly ash improves workability, strength, and durability; use in road and embankment construction where it provides benefits like lighter weight and higher strength; and use in brick manufacturing where it replaces clay. The document also notes the economic and environmental benefits of utilizing fly ash, such as reducing waste, lowering costs, and decreasing greenhouse gas emissions from cement production.
High volume fly ash concrete is a concrete where a replacement of about 35% or more of cement is made with the usage of fly ash.
Fly ash concrete is an eco-friendly construction material in which fly ash replaces a part of Portland cement.
Fly ash is a fine powder that is a byproduct of burning pulverized coal in electric generation power plants.
what is fly ash
fly ash products
coal fly ash uses
class f fly ash
fly ash class c
type f fly ash
fly ash composition
fly ash uses
applications of fly ash
advantages of fly ash
disadvantages of fly ash
properties of fly ash
chemical properties of fly ash
physical properties of fly ash
uses of fly ash
fly ash price
fly ash for sale
dangers of fly ash
fly ash in construction
fly ash composition
mechanism of fly ash
Type of Fly Ash as per American Society for Testing and Materials (ASTM C618)
Type of Fly Ash as per IS Codes (IS 3812-1981)
fly ash in construction
fly ash uses
what is fly ash
fly ash for sale
fly ash price
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ash construction inc
fly ash distributor
where to buy fly ash
fly ash for sale
fly ash suppliers usa
fly ash hazards
charah fly ash
fly ash price
fly ash in concrete problems
fly ash concrete
class c fly ash suppliers
class f fly ash
where to buy fly ash
class f fly ash composition
what is fly ash
cost of fly ash
fly ash distributor
fly ash for sale
fly ash ppt
basic knowledge about performance and characteristics of fly ash based concrete. this was my first presentation....so hard core civil engineers might consider me a layman!... anyway its a good way to start knowing gist and basics.
The document summarizes a seminar presentation on fly ash utilization and disposal. Fly ash is a byproduct of coal combustion in power plants. It can be utilized in construction materials like concrete and bricks to replace resources like cement, clay, and sand. It can also be used to reclaim land or stabilize soil. However, much of the fly ash currently produced worldwide is disposed of in landfills or ash ponds, which can pollute air, water, and soil if not properly managed. The presentation discusses the composition, types, production, uses, disposal methods, and environmental impacts of fly ash.
This document discusses the use of fly ash as a partial replacement for cement in concrete. It provides background on fly ash, including its generation from coal combustion and characteristics. Fly ash is classified as either Class F or Class C based on its chemical composition. The document outlines experimental programs conducted to study the effects of varying fly ash replacement levels on the workability and compressive strength of concrete. Test results showed workability decreased with higher fly ash content, while compressive strength increased up to 10% replacement but decreased at 15% replacement or more. The conclusion is that fly ash replacement of up to 10% is effective but may require plasticizers at higher replacement levels.
This document provides information on fly ash, which is a byproduct of coal combustion in coal-fired power plants. It discusses that fly ash is produced in large quantities annually in places like the US. The document covers the chemical composition and classes of fly ash, as well as how fly ash is used in concrete, bricks, embankments, soil stabilization, and other applications. It also addresses the recycling of fly ash, environmental impacts, and references for further information.
Flyash is a byproduct of coal combustion in thermal power plants. It can replace a portion of cement in concrete, improving workability, strength, and durability while reducing costs. Flyash particles react with lime released during cement hydration to form additional calcium silicate hydrates over long periods, filling spaces and strengthening concrete. Flyash concrete exhibits lower heat release and has applications where heat control and slower strength development are important, such as in large dams and foundations.
Fly ash is a byproduct of coal combustion in power plants. It consists of fine particles that rise with the flue gases and is one of the major air pollutants from combustion. Fly ash composition varies according to the parent coal but generally contains silicon dioxide, aluminum oxide, and iron oxide as major constituents. It is classified into Class C and Class F ash based on lime content. Fly ash has various applications including use in cement, soil stabilization, bricks, asphalt concrete, and embankments due to its pozzolanic properties. However, issues include potential groundwater contamination and difficulty using in winter due to slow setting times. Current fly ash utilization in India is around 25% but there is significant potential for
High volume fly ash concrete is a concrete where a replacement of about 35% or more of cement is made with the usage of fly ash.
Fly ash concrete is an eco-friendly construction material in which fly ash replaces a part of Portland cement.
Fly ash is a fine powder that is a byproduct of burning pulverized coal in electric generation power plants.
what is fly ash
fly ash products
coal fly ash uses
class f fly ash
fly ash class c
type f fly ash
fly ash composition
fly ash uses
applications of fly ash
advantages of fly ash
disadvantages of fly ash
properties of fly ash
chemical properties of fly ash
physical properties of fly ash
uses of fly ash
fly ash price
fly ash for sale
dangers of fly ash
fly ash in construction
fly ash composition
mechanism of fly ash
Type of Fly Ash as per American Society for Testing and Materials (ASTM C618)
Type of Fly Ash as per IS Codes (IS 3812-1981)
fly ash in construction
fly ash uses
what is fly ash
fly ash for sale
fly ash price
fly ash products
ash construction inc
fly ash distributor
where to buy fly ash
fly ash for sale
fly ash suppliers usa
fly ash hazards
charah fly ash
fly ash price
fly ash in concrete problems
fly ash concrete
class c fly ash suppliers
class f fly ash
where to buy fly ash
class f fly ash composition
what is fly ash
cost of fly ash
fly ash distributor
fly ash for sale
fly ash ppt
basic knowledge about performance and characteristics of fly ash based concrete. this was my first presentation....so hard core civil engineers might consider me a layman!... anyway its a good way to start knowing gist and basics.
The document summarizes a seminar presentation on fly ash utilization and disposal. Fly ash is a byproduct of coal combustion in power plants. It can be utilized in construction materials like concrete and bricks to replace resources like cement, clay, and sand. It can also be used to reclaim land or stabilize soil. However, much of the fly ash currently produced worldwide is disposed of in landfills or ash ponds, which can pollute air, water, and soil if not properly managed. The presentation discusses the composition, types, production, uses, disposal methods, and environmental impacts of fly ash.
This document discusses the use of fly ash as a partial replacement for cement in concrete. It provides background on fly ash, including its generation from coal combustion and characteristics. Fly ash is classified as either Class F or Class C based on its chemical composition. The document outlines experimental programs conducted to study the effects of varying fly ash replacement levels on the workability and compressive strength of concrete. Test results showed workability decreased with higher fly ash content, while compressive strength increased up to 10% replacement but decreased at 15% replacement or more. The conclusion is that fly ash replacement of up to 10% is effective but may require plasticizers at higher replacement levels.
This document provides information on fly ash, which is a byproduct of coal combustion in coal-fired power plants. It discusses that fly ash is produced in large quantities annually in places like the US. The document covers the chemical composition and classes of fly ash, as well as how fly ash is used in concrete, bricks, embankments, soil stabilization, and other applications. It also addresses the recycling of fly ash, environmental impacts, and references for further information.
Flyash is a byproduct of coal combustion in thermal power plants. It can replace a portion of cement in concrete, improving workability, strength, and durability while reducing costs. Flyash particles react with lime released during cement hydration to form additional calcium silicate hydrates over long periods, filling spaces and strengthening concrete. Flyash concrete exhibits lower heat release and has applications where heat control and slower strength development are important, such as in large dams and foundations.
Fly ash is a byproduct of coal combustion in power plants. It consists of fine particles that rise with the flue gases and is one of the major air pollutants from combustion. Fly ash composition varies according to the parent coal but generally contains silicon dioxide, aluminum oxide, and iron oxide as major constituents. It is classified into Class C and Class F ash based on lime content. Fly ash has various applications including use in cement, soil stabilization, bricks, asphalt concrete, and embankments due to its pozzolanic properties. However, issues include potential groundwater contamination and difficulty using in winter due to slow setting times. Current fly ash utilization in India is around 25% but there is significant potential for
The document discusses fly ash brick production and marketing strategies in West Bengal. It provides background on fly ash as a byproduct and building material. It then details: [1] Fly ash brick production processes and raw materials used; [2] Current state of the fly ash brick industry in West Bengal with 65 operating plants; [3] Marketing is primarily direct from manufacturers and through retailers, with transportation costs limiting rural markets. The document analyzes fly ash generation and usage data from power plants to support further growth of the fly ash brick sector in the state.
This document provides an overview of fly ash, including:
- Fly ash is a byproduct of burning coal in thermal power stations and contains silica, alumina, and iron oxide.
- There are four main types of ash: fly ash, bottom ash, pond ash, and mound ash. Fly ash has pozzolanic properties that react with calcium hydroxide.
- The Bureau of Indian Standards specifies chemical and physical requirements for fly ash used in cement and concrete.
- Fly ash has various uses including in bricks/blocks, cement concrete, road construction, agriculture, and mine filling. When used in concrete it improves workability, permeability, and long-term strength.
In this paper, the authors have discussed about the replacement of aggregates by discarded tyre rubber. This type of concrete is known as “Rubcrete”. It will cover the problems with the natural aggregate and also the reasons behind the use of rubber. The types of tyre rubber that are used, influence of size and content of rubber on concrete, effect of surface texture are discussed. Change in the properties of rubcrete over the conventional concrete, in hardened and fresh state such as slump, unit weight, air content, plastic shrinkage, mechanical strength been discussed. Paper covers the mechanisms behind the strength change, impact resistance, heat and sound insulation, freezing and thawing resistance of rubcrete. At the last, discussion on applications of rubcrete.
This document discusses fly ash, which is a byproduct of coal combustion that can be used in concrete production. It has three main points:
1. Fly ash can replace a portion of cement in concrete, improving properties like strength and durability while also reducing costs and environmental impact. Extensive research has shown fly ash improves long-term strength and density.
2. India produces around 75 million tons of fly ash per year but only utilizes around 5% of it due to lack of processing infrastructure. Increased fly ash use would help address disposal issues.
3. High-volume fly ash concrete mixes cement with 50-60% fly ash, requiring superplasticizers for workability but offering benefits like reduced heat
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
This document discusses metakaolin, which is produced by calcining kaolin clay between 650-800°C. It has pozzolanic properties and can partially replace cement in high strength concrete. Metakaolin increases the strength and durability of concrete by reacting with calcium hydroxide to produce additional calcium-silicate-hydrate gel. It improves the physical and chemical properties of concrete, leading to applications in infrastructure like bridges, dams, and buildings where high strength and durability are important.
Fly ash is a byproduct of coal combustion that can be used as a supplementary cementitious material in concrete. Using fly ash provides environmental benefits by reducing CO2 emissions from cement production and providing an outlet to dispose of the large amounts of fly ash produced annually. Fly ash improves the properties of concrete by increasing workability, reducing water demand, improving strength development over time, and decreasing permeability. The pozzolanic reaction of fly ash with lime from cement hydration leads to increased amounts of calcium silicate hydrate, enhancing the durability of the concrete.
Hydration is the chemical reaction between cement and water that forms bonds and results in a solid mass. The main compounds in cement - C3S, C2S, C3A, and C4AF - hydrate to form calcium silicate hydrates (C-S-H gel), calcium hydroxide, and calcium aluminate hydrates. Hydration is affected by factors like composition, fineness, water-cement ratio, and curing temperature. Special cements include acid-resistant, blast furnace, expanding, colored, high alumina, hydrophobic, low heat, and oil well cements used for their properties.
This document discusses fly ash bricks as an alternative to traditional clay bricks. Fly ash is a byproduct of coal combustion in power plants, and large amounts of fly ash are produced annually in India. Fly ash bricks have several advantages over clay bricks - they are lighter, stronger, and more insulative. Various types of fly ash bricks are described, including those made from mixing fly ash with soil or adding lime, gypsum or cement. Fly ash bricks can help utilize a waste product while providing a more sustainable building material.
Its all about the new environment friendly bricks that are now in more demand as compared to clay bricks. So how its useful and what it contains is explained here.
This document discusses ground granulated blast furnace slag (GGBFS), a byproduct of steel production that can be used in concrete production. It has several benefits over traditional Portland cement concrete including greater strength, durability, and sustainability. GGBFS concrete exhibits improved sulfate and chloride resistance, reduces temperatures in large pours, and results in a lighter colored, smoother finish. It also enhances workability and pumpability while requiring less water. Overall, incorporating GGBFS in concrete delivers higher performance while reducing costs and environmental impact.
This document discusses ash handling and utilization from coal combustion. It notes that ash reduces efficiency and increases costs. Ash comprises 80% fly ash and 20% bottom ash. Options for handling ash include disposal in dry or wet embankments or utilization. Utilization involves using fly ash in materials like bricks, concrete, and agriculture to save space and resources compared to disposal. Advantages of utilization are saving space and natural resources while reducing energy use and environmental impacts.
This document presents a summary of a student's project on using red mud concrete. The student investigated replacing Portland cement with red mud, a waste product from aluminum production, in concrete. The document outlines that 1-2.5 tons of red mud is created for every ton of alumina produced. Concrete cubes were cast using different percentages of red mud replacement and tested after 28 days, with compressive and tensile strength decreasing as red mud content increased. The conclusion is that red mud concrete is suitable for ornamental works where aesthetics are important.
why we use fly ash in concrete , production of fly ash, how it improve the fresh and harden properties of concrete
how it react when mix with concrete.
This document summarizes a seminar presentation on rice husk ash (RHA). RHA is obtained by burning rice husks between 600-700°C for 2 hours. It is composed primarily of silicon dioxide and can be used to partially replace cement in concrete production. The addition of RHA increases strength and durability by reducing calcium hydroxide levels in concrete. It also reduces efflorescence and susceptibility to chemical and sulfate attacks. Using RHA in concrete can help reduce carbon dioxide emissions from cement production and provides an economic use for the agricultural waste product of rice husks. The seminar outlines the physical and chemical properties of RHA and reviews its advantages and disadvantages when used in concrete.
Refuse derived fuel (RDF) is a fuel produced from various types of waste such as paper, plastic, wood and food waste. The RDF production process involves sorting, shredding, drying and pelletizing the waste into fuel pellets. RDF has a higher calorific value than coal and burns cleaner with lower emissions. It can be used in cement kilns, power plants and industrial boilers as a renewable alternative to fossil fuels. Producing RDF from municipal solid waste generates energy while reducing the amount of waste sent to landfills.
fly ash and rubber in concrete ( eco-friendly concrete)Koppolu Abishek
This study investigated the effects of partially replacing cement with fly ash and coarse aggregate with rubber chips in concrete. Concrete mixtures were prepared with 0%, 10%, and 20% fly ash replacement of cement and 5% rubber chip replacement of coarse aggregate. Fresh and hardened properties were tested. Test results found that 5% rubber replacement slightly reduced compressive strength compared to normal concrete. However, increasing fly ash content from 10% to 20% improved mechanical properties of the rubberized concrete. Therefore, partial replacement of cement with fly ash and coarse aggregate with rubber chips has potential to produce concrete with comparable strength to normal concrete while utilizing waste materials.
This document discusses red mud, a waste product generated during alumina production from bauxite using the Bayer process. It consists primarily of iron oxide (30-60%) along with other compounds such as aluminum oxide, silicon dioxide, sodium oxide and titanium oxide. Approximately 1-2.5 tons of red mud is produced per ton of alumina. The document outlines the environmental issues with disposing of red mud, including its high pH and potential contamination of groundwater. It also describes various methods used for storage and disposal, as well as research into neutralizing and utilizing red mud for applications such as construction materials and metal recovery.
Light weight concrete-materials properties and types. Typical light weight concrete mix High density concrete and high performance concrete-materials,properties and applications, typical mix.
Fly ash is a byproduct of coal combustion in thermal power plants. Huge quantities of fly ash are generated and can be used beneficially in road construction. Fly ash has physical and chemical properties making it suitable for use in embankments and as a stabilizer in subgrades and bases. When used in embankments, fly ash must be compacted properly and protected with an earthen cover to prevent erosion. Engineering tests are required to evaluate the properties of fly ash before using it in road construction. National highway authorities are increasingly using fly ash to reduce costs and promote sustainable construction practices.
12 btceng040,fly ash for concrete ppt by RITESHMANI TRIPATHIRiteshmani Tripathi
This document discusses fly ash, a byproduct of coal combustion in coal-fired power plants. It is collected from the flue gases through filtration systems. Fly ash composition can vary but generally contains silicon dioxide, calcium oxide, iron oxide and aluminum oxide. It is classified into Class C and Class F fly ash based on calcium content. The document discusses various uses of fly ash in concrete, bricks, soil stabilization, embankments and its benefits like reduced greenhouse gas emissions and landfill needs. However, it also notes concerns around potential leaching of toxic elements from fly ash.
1. Fly ash is a byproduct of coal combustion in coal-fired power plants. It is collected but must be disposed of or recycled.
2. There are two classes of fly ash defined by ASTM based on their composition. Class F fly ash generally performs better in concrete than Class C fly ash.
3. Over half of the 131 million tons of fly ash produced annually in the US is recycled, most often in concrete, which provides environmental and mechanical benefits over traditional concrete.
The document discusses fly ash brick production and marketing strategies in West Bengal. It provides background on fly ash as a byproduct and building material. It then details: [1] Fly ash brick production processes and raw materials used; [2] Current state of the fly ash brick industry in West Bengal with 65 operating plants; [3] Marketing is primarily direct from manufacturers and through retailers, with transportation costs limiting rural markets. The document analyzes fly ash generation and usage data from power plants to support further growth of the fly ash brick sector in the state.
This document provides an overview of fly ash, including:
- Fly ash is a byproduct of burning coal in thermal power stations and contains silica, alumina, and iron oxide.
- There are four main types of ash: fly ash, bottom ash, pond ash, and mound ash. Fly ash has pozzolanic properties that react with calcium hydroxide.
- The Bureau of Indian Standards specifies chemical and physical requirements for fly ash used in cement and concrete.
- Fly ash has various uses including in bricks/blocks, cement concrete, road construction, agriculture, and mine filling. When used in concrete it improves workability, permeability, and long-term strength.
In this paper, the authors have discussed about the replacement of aggregates by discarded tyre rubber. This type of concrete is known as “Rubcrete”. It will cover the problems with the natural aggregate and also the reasons behind the use of rubber. The types of tyre rubber that are used, influence of size and content of rubber on concrete, effect of surface texture are discussed. Change in the properties of rubcrete over the conventional concrete, in hardened and fresh state such as slump, unit weight, air content, plastic shrinkage, mechanical strength been discussed. Paper covers the mechanisms behind the strength change, impact resistance, heat and sound insulation, freezing and thawing resistance of rubcrete. At the last, discussion on applications of rubcrete.
This document discusses fly ash, which is a byproduct of coal combustion that can be used in concrete production. It has three main points:
1. Fly ash can replace a portion of cement in concrete, improving properties like strength and durability while also reducing costs and environmental impact. Extensive research has shown fly ash improves long-term strength and density.
2. India produces around 75 million tons of fly ash per year but only utilizes around 5% of it due to lack of processing infrastructure. Increased fly ash use would help address disposal issues.
3. High-volume fly ash concrete mixes cement with 50-60% fly ash, requiring superplasticizers for workability but offering benefits like reduced heat
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
This document discusses metakaolin, which is produced by calcining kaolin clay between 650-800°C. It has pozzolanic properties and can partially replace cement in high strength concrete. Metakaolin increases the strength and durability of concrete by reacting with calcium hydroxide to produce additional calcium-silicate-hydrate gel. It improves the physical and chemical properties of concrete, leading to applications in infrastructure like bridges, dams, and buildings where high strength and durability are important.
Fly ash is a byproduct of coal combustion that can be used as a supplementary cementitious material in concrete. Using fly ash provides environmental benefits by reducing CO2 emissions from cement production and providing an outlet to dispose of the large amounts of fly ash produced annually. Fly ash improves the properties of concrete by increasing workability, reducing water demand, improving strength development over time, and decreasing permeability. The pozzolanic reaction of fly ash with lime from cement hydration leads to increased amounts of calcium silicate hydrate, enhancing the durability of the concrete.
Hydration is the chemical reaction between cement and water that forms bonds and results in a solid mass. The main compounds in cement - C3S, C2S, C3A, and C4AF - hydrate to form calcium silicate hydrates (C-S-H gel), calcium hydroxide, and calcium aluminate hydrates. Hydration is affected by factors like composition, fineness, water-cement ratio, and curing temperature. Special cements include acid-resistant, blast furnace, expanding, colored, high alumina, hydrophobic, low heat, and oil well cements used for their properties.
This document discusses fly ash bricks as an alternative to traditional clay bricks. Fly ash is a byproduct of coal combustion in power plants, and large amounts of fly ash are produced annually in India. Fly ash bricks have several advantages over clay bricks - they are lighter, stronger, and more insulative. Various types of fly ash bricks are described, including those made from mixing fly ash with soil or adding lime, gypsum or cement. Fly ash bricks can help utilize a waste product while providing a more sustainable building material.
Its all about the new environment friendly bricks that are now in more demand as compared to clay bricks. So how its useful and what it contains is explained here.
This document discusses ground granulated blast furnace slag (GGBFS), a byproduct of steel production that can be used in concrete production. It has several benefits over traditional Portland cement concrete including greater strength, durability, and sustainability. GGBFS concrete exhibits improved sulfate and chloride resistance, reduces temperatures in large pours, and results in a lighter colored, smoother finish. It also enhances workability and pumpability while requiring less water. Overall, incorporating GGBFS in concrete delivers higher performance while reducing costs and environmental impact.
This document discusses ash handling and utilization from coal combustion. It notes that ash reduces efficiency and increases costs. Ash comprises 80% fly ash and 20% bottom ash. Options for handling ash include disposal in dry or wet embankments or utilization. Utilization involves using fly ash in materials like bricks, concrete, and agriculture to save space and resources compared to disposal. Advantages of utilization are saving space and natural resources while reducing energy use and environmental impacts.
This document presents a summary of a student's project on using red mud concrete. The student investigated replacing Portland cement with red mud, a waste product from aluminum production, in concrete. The document outlines that 1-2.5 tons of red mud is created for every ton of alumina produced. Concrete cubes were cast using different percentages of red mud replacement and tested after 28 days, with compressive and tensile strength decreasing as red mud content increased. The conclusion is that red mud concrete is suitable for ornamental works where aesthetics are important.
why we use fly ash in concrete , production of fly ash, how it improve the fresh and harden properties of concrete
how it react when mix with concrete.
This document summarizes a seminar presentation on rice husk ash (RHA). RHA is obtained by burning rice husks between 600-700°C for 2 hours. It is composed primarily of silicon dioxide and can be used to partially replace cement in concrete production. The addition of RHA increases strength and durability by reducing calcium hydroxide levels in concrete. It also reduces efflorescence and susceptibility to chemical and sulfate attacks. Using RHA in concrete can help reduce carbon dioxide emissions from cement production and provides an economic use for the agricultural waste product of rice husks. The seminar outlines the physical and chemical properties of RHA and reviews its advantages and disadvantages when used in concrete.
Refuse derived fuel (RDF) is a fuel produced from various types of waste such as paper, plastic, wood and food waste. The RDF production process involves sorting, shredding, drying and pelletizing the waste into fuel pellets. RDF has a higher calorific value than coal and burns cleaner with lower emissions. It can be used in cement kilns, power plants and industrial boilers as a renewable alternative to fossil fuels. Producing RDF from municipal solid waste generates energy while reducing the amount of waste sent to landfills.
fly ash and rubber in concrete ( eco-friendly concrete)Koppolu Abishek
This study investigated the effects of partially replacing cement with fly ash and coarse aggregate with rubber chips in concrete. Concrete mixtures were prepared with 0%, 10%, and 20% fly ash replacement of cement and 5% rubber chip replacement of coarse aggregate. Fresh and hardened properties were tested. Test results found that 5% rubber replacement slightly reduced compressive strength compared to normal concrete. However, increasing fly ash content from 10% to 20% improved mechanical properties of the rubberized concrete. Therefore, partial replacement of cement with fly ash and coarse aggregate with rubber chips has potential to produce concrete with comparable strength to normal concrete while utilizing waste materials.
This document discusses red mud, a waste product generated during alumina production from bauxite using the Bayer process. It consists primarily of iron oxide (30-60%) along with other compounds such as aluminum oxide, silicon dioxide, sodium oxide and titanium oxide. Approximately 1-2.5 tons of red mud is produced per ton of alumina. The document outlines the environmental issues with disposing of red mud, including its high pH and potential contamination of groundwater. It also describes various methods used for storage and disposal, as well as research into neutralizing and utilizing red mud for applications such as construction materials and metal recovery.
Light weight concrete-materials properties and types. Typical light weight concrete mix High density concrete and high performance concrete-materials,properties and applications, typical mix.
Fly ash is a byproduct of coal combustion in thermal power plants. Huge quantities of fly ash are generated and can be used beneficially in road construction. Fly ash has physical and chemical properties making it suitable for use in embankments and as a stabilizer in subgrades and bases. When used in embankments, fly ash must be compacted properly and protected with an earthen cover to prevent erosion. Engineering tests are required to evaluate the properties of fly ash before using it in road construction. National highway authorities are increasingly using fly ash to reduce costs and promote sustainable construction practices.
12 btceng040,fly ash for concrete ppt by RITESHMANI TRIPATHIRiteshmani Tripathi
This document discusses fly ash, a byproduct of coal combustion in coal-fired power plants. It is collected from the flue gases through filtration systems. Fly ash composition can vary but generally contains silicon dioxide, calcium oxide, iron oxide and aluminum oxide. It is classified into Class C and Class F fly ash based on calcium content. The document discusses various uses of fly ash in concrete, bricks, soil stabilization, embankments and its benefits like reduced greenhouse gas emissions and landfill needs. However, it also notes concerns around potential leaching of toxic elements from fly ash.
1. Fly ash is a byproduct of coal combustion in coal-fired power plants. It is collected but must be disposed of or recycled.
2. There are two classes of fly ash defined by ASTM based on their composition. Class F fly ash generally performs better in concrete than Class C fly ash.
3. Over half of the 131 million tons of fly ash produced annually in the US is recycled, most often in concrete, which provides environmental and mechanical benefits over traditional concrete.
Module on pozzolanic materials and fly ash ErankajKumar
This document discusses pozzolanic materials and fly ash. It defines pozzolanic materials as finely powdered materials that can be added to lime or cement mortar to increase durability through chemical reactions. The document outlines various natural and manufactured sources of pozzolanic materials including volcanic ash, burnt clay, slag, ashes of organic origin, and certain sands. It also discusses the properties and reactivity of pozzolans and their effects on mortar and concrete qualities like strength and stiffness. Additionally, the document defines fly ash as a byproduct of burning coal used in concrete for its cementitious properties. It notes the two main types of fly ash, Class C and Class F, and outlines fly ash's
Utilisation of Fly Ash in Cement ConcretePramey Zode
This document discusses the use of fly ash as a partial replacement for cement in concrete. Fly ash is a byproduct of coal combustion in thermal power plants. Using fly ash in concrete can reduce costs, improve workability and durability, and provide environmental benefits by reducing the amount of cement needed. The document examines the chemical properties of fly ash and how it reacts with cement. It recommends using fly ash to replace up to 50% of cement in high-volume fly ash concrete, which can further improve sustainability and concrete performance.
fly ash a_boon_for_concrete BY RAJ PREMANIRAJPREMANI
This document discusses the use of fly ash in concrete and other construction materials. Fly ash is a byproduct of coal combustion in power plants that is commonly disposed of in ash ponds. However, fly ash can be used beneficially in concrete, cement production, and brick making. When used to replace 15-30% of cement in concrete, fly ash increases strength and durability while reducing costs and greenhouse gas emissions from cement production. Fly ash bricks can be manufactured with less energy and emissions compared to clay bricks. Overall, the document promotes the use of fly ash as an eco-friendly and economical supplement in various construction materials.
The document discusses using fly ash as a partial replacement for cement in concrete. Fly ash is a byproduct of coal combustion in power plants. There are two classes of fly ash - Class F contains less than 7% lime and requires a cementing agent, while Class C has self-cementing properties due to more than 20% lime. The document explores the physical, chemical and geotechnical properties of fly ash. It finds that replacing cement with fly ash in concrete can improve strength, durability and reduce costs and CO2 emissions compared to traditional concrete. Common uses of fly ash include concrete, bricks/blocks, road construction and mine filling.
- Fly ash is a byproduct of coal burning in thermal power plants and is currently a major waste disposal problem.
- The document discusses using fly ash to produce bricks, cement, and fertilizer as ways to utilize it productively.
- Field trials showed that adding an optimal amount of fly ash to soil increased crop yields of rice and wheat, likely by improving soil structure and water retention. However, more research is needed before conclusions can be drawn.
IRJET- An Evaluation on the Composition of Coal Fly Ash and its Co-Placement ...IRJET Journal
This document analyzes the composition of coal fly ash and its potential use when mixed with concrete. Coal fly ash is a byproduct of coal combustion in power plants. It consists of fine glassy particles that are spherical in shape. The composition of fly ash depends on the type of coal burned, but generally contains silicon dioxide, aluminum oxide, and iron oxide. Fly ash is classified as Class C or Class F depending on its calcium oxide content. When mixed with concrete, fly ash can improve workability, decrease water demand, reduce heat generation, increase strength over time, and improve durability. Using fly ash as a partial cement replacement in concrete can thus provide benefits while reducing environmental impacts.
Fly ash is a byproduct of coal combustion that can be used as a supplementary cementitious material in concrete. There are two main classes of fly ash - Class F contains a greater combination of silica, alumina and iron, while Class C has a higher lime content. Fly ash particles fill voids in concrete, improving workability and reducing water requirements. While fly ash concrete has slightly lower early strength, it achieves higher ultimate strength and is more durable due to reduced permeability and alkali-silica reactivity. Using fly ash in concrete provides benefits like reduced heat of hydration, improved pumpability, and environmentally friendly use of an industrial byproduct.
Experimental Study On Strength Properties Of Geopolymer ConcreteIRJET Journal
This document presents the results of an experimental study on the strength properties of geopolymer concrete. Geopolymer concrete is made from fly ash, alkaline liquids like sodium hydroxide and sodium silicate, replacing ordinary Portland cement. The study investigated the compressive strength, flexural strength, Young's modulus, and deflection behavior of geopolymer concrete beams cured at 60°C for 24 hours. The results found that geopolymer concrete can achieve compressive strengths in the range of 20-35 MPa. The measured elastic modulus and Poisson's ratio values of geopolymer concrete were similar to ordinary concrete. The stress-strain behavior of geopolymer concrete under compression also fit well with models for ordinary concrete.
It consists of required concrete ingredients such as Cement, Fine Aggregate, coarse aggregate and water. Steps to reduce carbon footprint,Hydration of cement and M-sand introduction.
IRJET- Experimental Study of Concrete using Seashell and FlyashIRJET Journal
This document presents an experimental study on concrete using seashell and fly ash as partial replacements for cement and coarse aggregate. The study aims to reduce the cost of concrete. Concrete cubes were made with 10%, 20%, and 30% replacement of coarse aggregate with seashell. Additional mixes replaced 5%, 10%, and 15% of cement with fly ash. Compressive strength tests were conducted on the normal concrete and seashell/fly ash mixes. The strengths obtained from the alternative mixes are compared to conventional concrete to evaluate the use of industrial byproducts in concrete.
Synergistic Effect on Ternary Blended Cementitious Systemijtsrd
This paper presents a detailed experimental investigation on the synergestic effects on ternary blended cementitious system containing fly ash and silica fume. The experimental programme consisted of three parts, the first part was to obtain the super plasticizer demand for each mix so as to obtain a workability of 110±5 , the second part was to determine the strength and durability properties of the mortar samples having different fly ash and silica fume contents and the third part was to determine the synergy existing in the ternary blends both in terms of durability and strength. Test results have shown that the ternary blended mixtures improved the mortar performance by improving the workability, strength and durability, therefore are applicable. Ternary mixtures performed in accordance with their ingredients however the degree of improvement that they contribute varies based on the selected dosage and type of SCMs. Synergy between the fly ash and silica fume is the main reason for the outstanding performance of ternary mixtures. The results obtained thus are encouraging for partial replacement. Jasir Thachaparambil "Synergistic Effect on Ternary Blended Cementitious System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-7 , December 2022, URL: https://www.ijtsrd.com/papers/ijtsrd52289.pdf Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/52289/synergistic-effect-on-ternary-blended-cementitious-system/jasir-thachaparambil
The document discusses an experimental investigation into producing cost-effective geopolymer bricks. Geopolymer bricks are made from fly ash or GGBS activated by an alkaline solution. The study will make geopolymer bricks using fly ash and GGBS with sodium hydroxide and sodium silicate activators. Tests will evaluate the compressive strength, water absorption, acid resistance, and efflorescence of the geopolymer bricks. The goal is to manufacture affordable, high-quality geopolymer bricks as an alternative to traditional clay bricks.
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.
CELLULAR LIGHT WEIGHT CONCRETE BLOCKS WITH DIFFERENT MIX PROPORTIONSIjripublishers Ijri
Burnt Clay Brick is the predominant construction material in the country. The CO2 emissions in the brick manufacture
process have been acknowledged as a significant factor to global warming. Now-a-days there are so many technologies
involved in the recent development of concrete. Cellular Lightweight Concrete (CLC) is one of the recent emerging technology
in making concrete. The usage of Cellular Light-weight Concrete (CLC) gives a prospective solution to building
construction industry along with environmental preservation. By using this type of concrete, we have found so many
advantages when compared to the burnt clay bricks.
This document discusses various types of admixtures that are added to concrete to modify its properties. It describes 15 types of admixtures classified according to their function, including plasticizers, superplasticizers, retarders, accelerators, air-entraining agents, and pozzolanic materials. Common chemical admixtures are discussed in more detail, along with their effects on properties of fresh and hardened concrete. Mineral admixtures like fly ash, blast furnace slag, rice husk ash, and silica fume are also summarized in terms of their composition and impact on improving concrete quality and durability.
This document discusses various admixtures used in concrete, including fly ash, silica fume, rice husk ash, metakaoline, surkhi, and ground granulated blast furnace slag (GGBS). Fly ash is the most widely used pozzolanic material and can replace cement. Silica fume improves strength but increases water demand. Rice husk ash and metakaoline also improve properties. Surkhi was commonly used in India but quality varied. GGBS reduces water and heat of hydration when substituted for cement. These admixtures generally improve strength, permeability, and chemical resistance of concrete.
IRJET- Experimental Study on Flexural Behaviour of Flyash based Geopolymer Co...IRJET Journal
This document presents an experimental study on the flexural behavior of fly ash-based geopolymer concrete with the addition of ground granulated blast furnace slag (GGBS) as a supplementary cementitious material. Five mixes were tested with varying percentages of GGBS replacement of fly ash (0%, 10%, 20%, 30%, 40%). The mixes were tested at 7 and 28 days for compressive strength, split tensile strength, and flexural strength. The results showed that incorporating GGBS in geopolymer concrete can increase its strength properties while allowing curing at ambient temperatures. This research aims to develop sustainable "green concrete" as an alternative to ordinary Portland cement concrete that can reduce CO2 emissions in the construction industry
EXPERIMENTAL STUDY ON COIR FIBRE REINFORCED FLY ASH BASED GEOPOLYMER CONCRETE...IAEME Publication
Background/Objectives: By using the fly residue as option substance to bond in concrete it reduces the usage of normal Portland cement in usual concrete which results in the development of Geopolymer concrete furthermore in the lessening of CO2 levels which thusly reduces the Global Warming. Methods/Statistical analysis: This paper presents the trial examination done on the execution of coir fibre reinforced fly residue based geopolymer concrete subjected to severe ecological conditions. The mixes were considered for molarity of 10M. The basic arrangement utilized for present revise is the blend of sodium silicate and sodium hydroxide arrangement with the proportion of 1:2.5. Coir fibre with the varying percentages of 0, 0.75, 1.5, 2.25 and 3 are used as fibre reinforcement. The test specimens of 150mmx150mmx150mm cubes, 150mmx300mm cylinders, 1000mmx150mmx150mm beams are cast and cured under encompassing temperature conditions. Findings: The geopolymer solid examples are tried for their compressive quality, flexural and split tractable tests at 7days, 14days and 28days.The test grades demonstrate that the blend of fly ash and coir fibre can be used for the improvement of geopolymer concrete. Applications: It possesses superior distinctiveness such as high strength, very little drying shrinkage , low creep, durable nature, eco-friendly, fire proof ,better compressive strength etc to be used as an alternative of OPC.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
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Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
International Conference on NLP, Artificial Intelligence, Machine Learning an...gerogepatton
International Conference on NLP, Artificial Intelligence, Machine Learning and Applications (NLAIM 2024) offers a premier global platform for exchanging insights and findings in the theory, methodology, and applications of NLP, Artificial Intelligence, Machine Learning, and their applications. The conference seeks substantial contributions across all key domains of NLP, Artificial Intelligence, Machine Learning, and their practical applications, aiming to foster both theoretical advancements and real-world implementations. With a focus on facilitating collaboration between researchers and practitioners from academia and industry, the conference serves as a nexus for sharing the latest developments in the field.
CHINA’S GEO-ECONOMIC OUTREACH IN CENTRAL ASIAN COUNTRIES AND FUTURE PROSPECTjpsjournal1
The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
reserves and the ancient silk trade route, along with China's diplomatic endeavours in the area, has been
referred to as the "New Great Game." This research centres on the power struggle, considering
geopolitical, geostrategic, and geoeconomic variables. Topics including trade, political hegemony, oil
politics, and conventional and nontraditional security are all explored and explained by the researcher.
Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
in Central Asia. This study adheres to the empirical epistemological method and has taken care of
objectivity. This study analyze primary and secondary research documents critically to elaborate role of
china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
pipeline politics, and winning states, according to this study, thanks to important instruments like the
Shanghai Cooperation Organisation and the Belt and Road Economic Initiative. According to this study,
China is seeing significant success in commerce, pipeline politics, and gaining influence on other
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Cooperation Organisation and the Belt and Road Economic Initiative.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
LLM Fine Tuning with QLoRA Cassandra Lunch 4, presented by Anant
Fly ash utilization
1. [Type text] Page 1
Contents
Abstract...............................................................................................3
INTRODUCTION....................................................................................6
COMPOSTION ......................................................................................8
CLASSIFICATION...................................................................................9
Class F fly ash...........................................................................9
Class C fly ash...........................................................................9
APPLICATIONOF FLY ASH ...................................................................11
RECYCLING AND REUSE.......................................................................11
AREAS OF APPLICATION......................................................................12
3.1 Advantages of using fly ash for road and embankment construction
..........................................................................................................13
3.2. Economy in use of fly ash.............................................................16
3.3. Environmental Impact of Fly ash use ............................................17
APPLICATION IN CONCRETE................................................................18
4.1. Features of fly ash concrete .........................................................18
4.2. Contribution to Workability..........................................................20
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4.3. Contribution to Strength..............................................................21
4.4. Environmental Impact..................................................................22
APPLICATIONIN BRICKS......................................................................23
5.1. Features of Fly ash bricks .............................................................24
5.2. Environmental Impacts ................................................................25
5.3. Economic Benefit.........................................................................26
INDIAN SCENARIO IN FLY ASH APPLICATIONS ......................................27
Ash Concrete......................................................................................28
Advantages and Disadvantages of Using Fly ash In Concrete................28
The disadvantages of using fly ash in concrete ....................................31
Chemical composition and classification .............................................32
Disposal and market sources ..............................................................36
Environmental problems ....................................................................38
Exposure concerns .............................................................................43
CONCLUSION .....................................................................................44
REFERENCES:......................................................................................47
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Abstract
India has a vast coal reserve of 211 billion tones making
coal one of the most extensively used fossil fuel for
generating power. More than 175 million tones of fly ash
are expected to be generated in the country due to
combustion of coal by the year 2012. This would require
about 40000 hectares of land for the construction of ash
ponds for ash disposal.
Power plant ashes are generated as the finer pozzolanic
fly ash. Recognizing the reutilization of fly ash, the huge
pressures on land and water and the grave environmental
consequences, power plants are shifting to separating the
bottom ash and the fly ash and collecting ash to send it to
alternative users.
Fly ash utilization has great potential to lower green house
gas emissions by decreased mining activities and reducing
Carbon dioxide production during manufacture of
materials that can be substituted by fly ash. Fly ash holds
a potential to improve the physical health of the soil.
Owing to its pozzolanic properties, fly ash is used as a
replacement for some of the Portland cement content of
concrete .Use of fly ash as a partial replacement for
Portland cement is generally limited to Class F fly
ashes.Fly ash can substitute up to 66% of cement in the
construction of dams. It is also used as a pozzolanic
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substitute for cement in Roller Compacted Concrete dams.
Fly ash from coal fired thermal power plants is an
excellent material for the manufacture of other
construction materials like fly ash bricks, mosaic tiles and
hollow blocks. The manufacture of conventional clay bricks
requires the consumption of large amounts of clay. This
depletes top soil and leads to degradation of land. Some
of the high volume applications of fly ash are for use in
paving, building embankments and mine fills. Utilizing fly
ash in bricks and roads saves top soil, avoids creation of
low lying areas, does not deprive the nation of the
productivity of top soil and reduces the demand of land for
fly ash disposal. It also finds use in stabilization of soil, in
flowable fills and mine reclamation.
Various experimental research activities have revealed
that use of fly ash contributes towards enhancing the
property of the material in which it is used. Their use
contributes towards higher durability, lower shrinkage,
reduced heat of hydration, higher long term strength and
decreased permeability. Due to the spherical shape of fly
ash particles, it increases the workability of cement while
reducing water demand.
The use of fly ash has really good impacts on the
environment. The replacement of Portland cement with fly
ash is considered by its promoters to reduce the
greenhouse gas "footprint" of concrete, as the production
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of one ton of Portland cement produces approximately one
ton of carbon dioxide as compared to zero CO2 being
produced using existing fly ash. Utilization of fly ash not
only minimizes the disposal problem but also help in
utilizing land in a better way. The Indian Government has
taken a lot of initiatives and made certain stipulations to
encourage reuse of fly ash. Proper and efficient use of fly
ash results in saving of hundreds of crores of rupees
resulting in a positive impact on the economy.
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Project Member
INTRODUCTION
7. Optimization in FLY ASH PPC
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Fly ash is one of the residues generated in combustion,
and comprises of fine particles that rise with the flue
gases. In an industrial context, fly ash usually refers to
ash produced during combustion of coal. Fly ash is
produced through the combustion of coal used to generate
electricity. After coal is pulverized, it enters a boiler where
flame temperatures reach up to 1500 degrees Celsius.
Upon cooling, the inorganic matter transforms from a
vapour state to a liquid and solid state. During this
process individual, spherical particles are formed. This is
fly ash. It is then collected by either using electrostatic
precipitators, bag houses or a combination of both. Fly
ash from these systems is collected in hoppers and then
transferred to storage silos. Fly ash is tested for physical
properties such as fineness, loss on ignition, and
moisture, before it is allowed to be shipped to its end
user.
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COMPOSTION
They consist mostly of silicon dioxide (SiO2 ), aluminium
oxide (Al2O3) and iron oxide (Fe2O3). The chemical
properties of the fly ash are largely influenced by the
chemical content of the coal burned (i.e., anthracite,
bituminous, and lignite).
Fly ash also contains environmental toxins in significant
amounts, including arsenic (43.4 ppm); barium (806
ppm); beryllium (5 ppm); boron (311 ppm); cadmium
(3.4 ppm); chromium (136 ppm); chromium VI (90 ppm);
cobalt (35.9 ppm); copper (112 ppm); fluorine (29 ppm);
lead (56 ppm); manganese (250 ppm); nickel (77.6
ppm); selenium (7.7 ppm); strontium (775 ppm);
thallium (9 ppm); vanadium (252 ppm); and zinc (178
ppm).
Fly ashes are generally highly heterogeneous, consisting
of a mixture of glassy particles with various identifiable
crystalline phases such as quartz, mullite, and various iron
oxides.
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CLASSIFICATION
Two classes of fly ash are defined by ASTM C618:
1.Class F fly ash
2.Class C fly ash
The chief difference between these classes is the amount
of calcium, silica, alumina, and iron content in the ash.
Class F fly ash
Class F fly ash is produced by the burning of harder, older
anthracite and bituminous coal. This fly ash is pozzolanic
in nature, and contains less than 20% lime (CaO).
Possessing pozzolanic properties, the glassy silica and
alumina of Class F fly ash requires a cementing agent,
such as Portland cement, quicklime, or hydrated lime,
with the presence of water in order to react and produce
cementitious compounds.
Class C fly ash
Class C fly ash is produced from the burning of younger
lignite or sub-bituminous coal, in addition to having
pozzolanic properties, also has some self-cementing
properties. In the presence of water, Class C fly ash will
harden and gain strength over time. Class C fly ash
generally contains more than 20% lime (CaO). Unlike
Class F, self-cementing Class C fly ash does not require an
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activator. Alkali and sulfate (SO4) contents are generally
higher in Class C fly ashes. Class C will generate more
heat of hydration than Class F. Class C ash will generate
more strength at early ages than Class F.
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APPLICATION OF FLY ASH
RECYCLING AND REUSE
The recycling of fly ash has become an increasing
concern in recent years due to increasing landfill costs
and current interest in sustainable development.
Recognizing the reutilization of fly ash, the huge
pressures on land and water and the grave
environmental consequences, power plants are shifting
to separating the bottom ash and the fly ash and
collecting ash to send it to alternative users
The reuse of fly ash as an engineering material
primarily stems from its –
1)Spherical shape:
Less water is needed which ultimately makes the
concrete stronger and reduces particle segregation
while the concrete sets and improves workability while
the concrete is being finished.
Pumping properties are improved as the round
particles essentially act as a lubricant.
Cohesion between the cement paste and aggregate is
also improved since the particles are so fine.
2) Pozzolanic properties
3) Relative uniformity
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AREAS OF APPLICATION
Portland cement
Embankments and structural fill
Waste stabilization and solidification
Raw feed for cement clinkers.
Mine reclamation
Stabilization of soils
Road sub-base
Agriculture related applications
Aggregate
Flowable fill
Mineral filler in Asphaltic concrete
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APPLICATION OF FLY ASH IN ROADS
AND EMBANKMENTS
3.1 Advantages of using fly ash
for road and embankment
construction
Fly ash is a lightweight material, as compared to
commonly used fill material i.e. local soils, therefore,
causes lesser settlements. It is especially attractive for
embankment construction over weak sub grade such as
alluvial clay or silt where excessive weight could cause
failure.
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Fly ash embankments can be compacted over a wide
range of moisture content, and therefore, results in less
variation in density with changes in moisture content.
Easy to handle and compact because the material is
light and there are no large lumps to be broken down.
Compaction can be done using either vibratory or static
rollers.
High permeability ensures free and efficient drainage.
After rainfall, water gets drained out freely ensuring
better workability than soil. Work on fly ash fills/
embankments can be restarted within a few hours after
rainfall, while in case of soil it takes much longer.
Fly ash has considerably low compressibility resulting in
negligible subsequent settlement within the fill.
Use of fly ash helps in conserving good earth, which is
precious topsoil, thereby protecting the environment.
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Devendra Kumar Patel Page 15
It has higher value of California Bearing Ratio as
compared to soil thus, providing for a more efficient
design of road pavement.
Pozzolanic hardening property imparts additional
strength to the road pavements/ embankments and
decreases the post construction horizontal pressure on
retaining walls.
Fly ash is amenable to stabilisation with lime and
cement.
It can replace a part of cement and sand in concrete
pavements thus making them more economical than
roads constructed using conventional materials.
Fly ash admixed concrete can be prepared with zero
slump making it amenable for use as roller compacted
concrete.
Considering all these advantages, it is extremely
essential to promote use of fly ash for construction of
roads and embankments.
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3.2. Economy in use of fly ash
Use of fly ash in road works results in reduction in
construction cost by about 10 to 20 per cent. Typically
cost of borrow soil varies from about Rs.100 to 200 per
cubic metre. Fly ash is available free of cost at the power
plant and hence only transportation cost, laying and
rolling cost are there in case of fly ash. Hence, when fly
ash is used as a fill material, the economy achieved is
directly related to transportation cost of fly ash. If the
lead distance is less, considerable savings in construction
cost can be achieved. Similarly, the use of fly ash in
pavement construction results in significant savings due to
savings in cost of road aggregates. If environmental
degradation costs due to use of precious top soil and
aggregates from borrow areas quarry sources and loss of
fertile agricultural land due to ash deposition etc. the
actual savings achieved will be much higher.
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Devendra Kumar Patel Page 17
3.3. Environmental Impact of
Fly ash use
Utilization of fly ash not only minimizes the disposal
problem but also help in utilizing land in a better way.
Construction of road embankments using fly ash
involves encapsulation of fly ash in earthen core or with
RCC facing panels. Since there is no seepage of rain
water into the fly ash core, leaching of heavy metals is
also prevented. When fly ash is used in concrete, it
chemically reacts with cement and reduces any leaching
effect.
In stabilization work, a similar chemical reaction takes
place which binds fly ash particles.
Hence chances of pollution due to use of fly ash in road
works are negligible
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APPLICATION IN CONCRETE
4.1. Features of fly ash concrete
Higher durability
It is more resistant to attack by sulfate, mild acid,
soft water and sea water.
Similar abrasion resistance to as that of normal
concrete
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Relatively lower drying shrinkage
The lubricating action of fly ash reduces the water
content and thus drying shrinkage.
Reduced heat of hydration
The pozzolanic reaction between fly ash and lime
generates less heat, resulting in reduced thermal
cracking when fly ash is used to reduce Portland
cement
Reduced sulphate attack and reduced
efflorescence.
Fly ash ties up free lime that can create efflorescence
and also combine with sulfates to create destructive
expansion.
High strength
Fly ash continues to combine with free lime,
increasing compressive strength over time.
Decreased permeability
Increased density and long term pozzolanic action of
fly ash, which ties up free lime, results in fewer bleed
channels and decreases permeability.
Higher setting time
This is beneficial in hot weather as it allows more
time for transporting and placing concrete. In cold
weather, excessive set retardation can be avoided by
raising the temperature or using set accelerating
admixtures.
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4.2. Contribution to Workability
Light weight concrete
Easier to pump as pumping requires less energy
Improved finishing:
This results in creamier texture and sharp, clearer
architectural definition is easier to achieve
Reduced segregation and bug holes
Improved cohesiveness of fly ash reduces
segregation.
Reduced Bleeding
Fewer bleed channels decrease permeability and
chemical attack. Bleeding
of HVFAC ranges from negligible values to low
values due to its very low
water content.
Less sand needed in the mix to produce required
workability.
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4.3. Contribution to Strength
Cement normally gains majority of its strength within 28
days. So the specifications normally require the 28-day
strength as standard. Typically concrete made with fly ash
will be slightly lower in strength than straight cement
concrete upto 28 days, almost equal strength at 28 days
and substantially higher strength within a year’s time.
Conversely in cement concrete, this lime would remain
intact and over time it would be susceptible to the effects
of weathering and loss of strength and durability
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4.4. Environmental Impact
Studies show that one ton of Portland cement production
discharges 0.87 tonnes of Carbon dioxide in the
Environment. Another Japanese study indicates that every
year barren land approximately 1.5 times of the Indian
Territory need to be afforested to compensate for the total
global accumulation of Carbon Dioxide discharged into the
atmosphere because of total global cement production.
The replacement of Portland cement with fly ash is
considered by its promoters to reduce the green house
gas "footprint" of concrete, as the production of one ton of
Portland cement produces approximately one ton of
carbon dioxide as compared to zero CO2 being produced
using existing fly ash. Utilization of fly ash in cement
concrete minimizes the Carbon dioxide emission problem
to the extent of its proportion in cement.
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APPLICATION IN BRICKS
Bricks made of lime and sand, popularly known as calcium
silicate bricks are hardened by high pressure steam
curing. The process requires finely ground sand. Fly ash,
which is already fine, replaces ground sand partially or
totally, thus conserving on grinding costs. Being a
pozzolan, fly ash also reacts with lime resulting in bricks
of superior quality.
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Devendra Kumar Patel Page 24
5.1. Features of Fly ash bricks
Good earthquake resistance features
Fire resistant
Easy handling and faster construction
Excellent acoustic barriers
Reduction in plastering almost by 50% due to even
walls
Due to high strength, practically no breakage during
transport & use
No soaking in water required for 24 hours. Only
sprinkling of water before use.
Good freeze-thaw resistance.
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5.2. Environmental Impacts
The Various environmental concerns regarding fly ash
bricks are
Potential for radon and mercury vapor emission
Potential for leaching pollutants (heavy metals)
Potential for polluting landfills when building is
demolished and broken fly ash products enter
landfills.
But the bricks made out of fly ash have been found to
be environmentally safe .
Fly ash bricks made from class C fly ash do not emit
mercury into air. On contrary they adsorb mercury
from air, making ambient air cleaner .
They emit radon but only 50% of what is emitted by
concrete. So safe to use.
Leaching of pollutants from fly ash bricks caused by
rain is negligible
They are non-hazardous for land fills.
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5.3. Economic Benefit
180 billion tonnes of clay brick production per year
consumes 540 million tonnes of clay, makes 65000
acres of land barren, and consumes 30 million tonnes of
coal equivalent, generates26 million tonnes of Carbon
Dioxide. A 10% switchover to fly ash bricks will use 30
million tonnes of fly ash every year, save environment
and coal and yield a benefit of 300 crores by way of
reduction in brick cost production
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INDIAN SCENARIO IN FLY ASH
APPLICATIONS
The Fly-ash mission was commissioned in 1994 with
the Department of Science and Technology as the
nodal agency and the Technology Information and
Assessment Council (TIFAC) as the implementing
agency. The Ministry of Environment and Forests, Govt.
of India, Ministry of Power, Thermal Power stations,
R&D Institutions and Industry together have launched
a Technology Project in Mission Mode (TPMM). Their
focus is on the demonstration of coal ash related
technologies for infusing confidence and thus ensuring
large scale adoption
The Government of India has withdrawn the 8% excise
duty imposed earlier on fly ash products. Now no
excise duty is levied on manufacture of goods in which
a minimum of 25% w/w fly ash is used.
Government of Orissa has exempted fly ash bricks and
other products from sales tax.
Financial support, in many forms, is being extended to
promote industrial units for production of building
materials based on fly ash products.
Ministry of Environment and Forests (MOEF) and
Ministry of Power stipulations are made for 20% Fly
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Ash Concrete
Advantages and Disadvantages
of Using Fly ash In Concrete
Fly ash is the residue that is left from burning coal, and
this is formed when the gaseous releases of the coal is
efficiently cooled. It is somewhat like a glass powder
that is fine in nature. However, the chemical
constituents of this residue might vary from one other.
Fly ash has several industrial applications and is widely
found in power plant chimneys. The material is also
used as substitute cement by mixing it with lime and
water. The material is embedded with myriad beneficial
features and so is being utilized as a significant building
material for the construction purposes. This type of
concrete is much dense and smooth. Below listed are
few of the advantages and disadvantages of fly ash
concrete.
The Pros and Cons of Using Fly ash
Fly ash is used in many countries because of its
advantages. There are also some disadvantages of using
fly ash in concrete. These pros and cons are described
in brief below.
The significant benefits of using fly ash in concrete
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The advantages of using fly ash in concrete
includes the followings.
Fly ash in the concrete mix efficiently replaces
Portland cement that in turn can aid in making big
savings in concrete material prices.
It is also an environmentally-friendly solution, which
meets the performance specifications. It can also
contribute to LEED points.
It improves the strength over time and thus, it offers
greater strength to the building.
Increased density and also the long-term
strengthening action of flash that ties up with free
lime and thus, results in lower bleed channels and
also decreases the permeability.
The reduced permeability of concrete by using fly
ash, also aids to keep aggressive composites on the
surface where the damaging action is reduced. It is
also highly resistant to attack by mild acid, water
and sulfate.
It effectively combines with alkalis from cement,
which thereby prevents the destructive expansion.
It is also helpful in reducing the heat of hydration.
The pozzolanic reaction in between lime and fly ash
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will significantly generate less heat and thus,
prevents thermal cracking.
It chemically and effectively binds salts and free
lime, which can create efflorescence. The lower
permeability of fly ash concrete can efficiently reduce
the effects of efflorescence.
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The disadvantages of using fly
ash in concrete
There are also some disadvantages of using fly ash that
should be considered.
The quality of fly ash to be utilized is very vital. Poor
quality often has a negative impact on the concrete.
The poor quality can increase the permeability and thus
damaging the building.
Some fly ash, those are produced in power plant is
usually compatible with concrete, while some other
needs to be beneficiated, and few other types cannot
actually be improved for using in concrete. Thus, it is
very much vital to use only high quality fly ash to
prevent negative effects on the structure of the building.
The aforesaid is few advantages and disadvantages of
fly ash concrete. This type of concrete offers many
advantages and as mentioned above it also has some
disadvantages. There are various other advantages of
utilizing fly ash concrete such as it is much easier to
place with reduced effort and it is also able to have
improved finishing to the structure with such type of
concrete. Fly ash concrete can certainly add greater
strength to the building.
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Chemical composition and
classification
ComponentBituminous Subbituminous Lignite
SiO2 (%) 20-60 40-60 15-45
Al2O3 (%) 5-35 20-30 20-25
Fe2O3 (%) 10-40 4-10 4-15
CaO (%) 1-12 5-30 15-40
LOI (%)0-15 0-3 0-5
Fly ash material solidifies while suspended in the
exhaust gases and is collected by electrostatic
precipitators or filter bags. Since the particles solidify
rapidly while suspended in the exhaust gases, fly ash
particles are generally spherical in shape and range in
size from 0.5 µm to 300 µm. The major consequence of
the rapid cooling is that few minerals have time to
crystallize, and that mainly amorphous, quenched glass
remains. Nevertheless, some refractory phases in the
pulverized coal do not melt (entirely), and remain
crystalline. In consequence, fly ash is a heterogeneous
material. SiO2, Al2O3, Fe2O3 and occasionally CaO are
the main chemical components present in fly ashes. The
mineralogy of fly ashes is very diverse. The main phases
encountered are a glass phase, together with quartz,
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mullite and the iron oxides hematite, magnetite and/or
maghemite. Other phases often identified are
cristobalite, anhydrite, free lime, periclase, calcite,
sylvite, halite, portlandite, rutile and anatase. The Ca-
bearing minerals anorthite, gehlenite, akermanite and
various calcium silicates and calcium aluminates
identical to those found in Portland cement can be
identified in Ca-rich fly ashes.[5] The mercury content
can reach 1 ppm,[6] but is generally included in the
range 0.01 - 1 ppm for bituminous coal. The
concentrations of other trace elements vary as well
according to the kind of coal combusted to form it. In
fact, in the case of bituminous coal, with the notable
exception of boron, trace element concentrations are
generally similar to trace element concentrations in
unpolluted soils.
Two classes of fly ash are defined by ASTM C618: Class
F fly ash and Class C fly ash. The chief difference
between these classes is the amount of calcium, silica,
alumina, and iron content in the ash. The chemical
properties of the fly ash are largely influenced by the
chemical content of the coal burned (i.e., anthracite,
bituminous, and lignite).[8]
Not all fly ashes meet ASTM C618 requirements,
although depending on the application, this may not be
necessary. Ash used as a cement replacement must
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meet strict construction standards, but no standard
environmental regulations have been established in the
United States. 75% of the ash must have a fineness of
45 µm or less, and have a carbon content, measured by
the loss on ignition (LOI), of less than 4%. In the U.S.,
LOI must be under 6%. The particle size distribution of
raw fly ash tends to fluctuate constantly, due to
changing performance of the coal mills and the boiler
performance. This makes it necessary that, if fly ash is
used in an optimal way to replace cement in concrete
production, it must be processed using beneficiation
methods like mechanical air classification. But if fly ash
is used also as a filler to replace sand in concrete
production, unbeneficiated fly ash with higher LOI can
be also used. Especially important is the ongoing quality
verification. This is mainly expressed by quality control
seals like the Bureau of Indian Standards mark or the
DCL mark of the Dubai Municipality.
Class F fly ash
The burning of harder, older anthracite and bituminous
coal typically produces Class F fly ash. This fly ash is
pozzolanic in nature, and contains less than 7% lime
(CaO). Possessing pozzolanic properties, the glassy
silica and alumina of Class F fly ash requires a
cementing agent, such as Portland cement, quicklime,
or hydrated lime—mixed with water to react and
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produce cementitious compounds. Alternatively, adding
a chemical activator such as sodium silicate (water
glass) to a Class F ash can form a geopolymer.
Class C fly ash[edit]
Fly ash produced from the burning of younger lignite or
sub-bituminous coal, in addition to having pozzolanic
properties, also has some self-cementing properties. In
the presence of water, Class C fly ash hardens and gets
stronger over time. Class C fly ash generally contains
more than 20% lime (CaO). Unlike Class F, self-
cementing Class C fly ash does not require an activator.
Alkali and sulfate (SO
4) contents are generally higher in Class C fly ashes.
At least one US manufacturer has announced a fly ash
brick containing up to 50% Class C fly ash. Testing
shows the bricks meet or exceed the performance
standards listed in ASTM C 216 for conventional clay
brick. It is also within the allowable shrinkage limits for
concrete brick in ASTM C 55, Standard Specification for
Concrete Building Brick. It is estimated that the
production method used in fly ash bricks will reduce the
embodied energy of masonry construction by up to
90%.[9] Bricks and pavers were expected to be
available in commercial quantities before the end of
2009.[10]
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Disposal and market sources
In the past, fly ash produced from coal combustion was
simply entrained in flue gases and dispersed into the
atmosphere. This created environmental and health
concerns that prompted laws that have reduced fly ash
emissions to less than 1% of ash produced. Worldwide,
more than 65% of fly ash produced from coal power
stations is disposed of in landfills and ash ponds,
although companies such as Duke Energy are starting
initiatives to excavate coal ash basins due to the
negative environmental impact involved.
The recycling of fly ash has become an increasing
concern in recent years due to increasing landfill costs
and current interest in sustainable development. As of
2005, U.S. coal-fired power plants reported producing
71.1 million tons of fly ash, of which 29.1 million tons
were reused in various applications.[11] If the nearly 42
million tons of unused fly ash had been recycled, it
would have reduced the need for approximately 27,500
acre·ft (33,900,000 m3) of landfill space.[11][12] Other
environmental benefits to recycling fly ash includes
reducing the demand for virgin materials that would
need quarrying and cheap substitution for materials
such as Portland cement.
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As of 2006, about 125 million tons of coal-combustion
byproducts, including fly ash, were produced in the U.S.
each year, with about 43% of that amount used in
commercial applications, according to the American Coal
Ash Association Web site. As of early 2008, the United
States Environmental Protection Agency hoped that
figure would increase to 50% as of 2011.[13]
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Environmental problems
Present production rate of fly ash
In the United States about 131 million tons of fly ash
are produced annually by 460 coal-fired power plants. A
2008 industry survey estimated that 43% of this ash is
re-used.
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Groundwater contamination
Since coal contains trace levels of trace elements (like
e.g. arsenic, barium, beryllium, boron, cadmium,
chromium, thallium, selenium, molybdenum and
mercury), fly ash obtained after combustion of this coal
contains enhanced concentrations of these elements,
and therefore the potential of the ash to cause
groundwater pollution needs to be evaluated. In the
USA there are documented cases of groundwater
pollution which followed ash disposal or utilization
without the necessary protection means.
In 2014, residents living near the Buck Steam Station in
Dukeville, North Carolina, were told that "coal ash pits
near their homes could be leaching dangerous materials
into groundwater."
Spills of bulk storage
Tennessee Valley Authority Fly Ash containment failure
on 23 December 2008 in Kingston, Tennessee
Where fly ash is stored in bulk, it is usually stored wet
rather than dry to minimize fugitive dust. The resulting
impoundments (ponds) are typically large and stable for
long periods, but any breach of their dams or bunding is
rapid and on a massive scale.
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In December 2008, the collapse of an embankment at
an impoundment for wet storage of fly ash at the
Tennessee Valley Authority's Kingston Fossil Plant
caused a major release of 5.4 million cubic yards of coal
fly ash, damaging 3 homes and flowing into the Emory
River. Cleanup costs may exceed $1.2 billion. This spill
was followed a few weeks later by a smaller TVA-plant
spill in Alabama, which contaminated Widows Creek and
the Tennessee River.
In 2014, tens of thousands of tons of ash and 27 million
gallons (100,000 cubic meters) of contaminated water
spilled into the Dan River near Eden, NC from a closed
North Carolina coal-fired power plant that is owned by
Duke Energy. It is currently the third worst coal ash spill
ever to happen in the United States.[40][41] A 48-inch
(120 cm) pipe spilled arsenic and other heavy metals
into the river for a week, but was successfully plugged
by Duke Energy. The U.S. federal government plans to
investigate, and people along the river have been
warned to stay away from the water. Fish have yet to
be tested, but health officials say not to eat them.[42]
New regulations published in the Federal Register on
December 19, 2015 stipulate a comprehensive set of
rules and guidelines for safe disposal and storage.[43]
Designed to prevent pond failures and protect
groundwater, enhanced inspection, record keeping and
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monitoring is specified. Procedures for closure are also
included and include capping, liners, and dewatering.
Contaminants
Fly ash contains trace concentrations of heavy metals
and other substances that are known to be detrimental
to health in sufficient quantities. Potentially toxic trace
elements in coal include arsenic, beryllium, cadmium,
barium, chromium, copper, lead, mercury,
molybdenum, nickel, radium, selenium, thorium,
uranium, vanadium, and zinc.[45][46] Approximately
10% of the mass of coals burned in the United States
consists of unburnable mineral material that becomes
ash, so the concentration of most trace elements in coal
ash is approximately 10 times the concentration in the
original coal.[47] A 1997 analysis by the U.S. Geological
Survey (USGS) found that fly ash typically contained 10
to 30 ppm of uranium, comparable to the levels found in
some granitic rocks, phosphate rock, and black
shale.[47]
In 2000, the United States Environmental Protection
Agency (EPA) said that coal fly ash did not need to be
regulated as a hazardous waste.[48] Studies by the U.S.
Geological Survey and others of radioactive elements in
coal ash have concluded that fly ash compares with
common soils or rocks and should not be the source of
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alarm.[47] However, community and environmental
organizations have documented numerous
environmental contamination and damage
concerns.[49][50][51]
A revised risk assessment approach may change the
way coal combustion wastes (CCW) are regulated,
according to an August 2007 EPA notice in the Federal
Register.[52] In June 2008, the U.S. House of
Representatives held an oversight hearing on the
Federal government's role in addressing health and
environmental risks of fly ash.
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Exposure concerns
Crystalline silica and lime along with toxic chemicals are
among the exposure concerns. Although industry has
claimed that fly ash is "neither toxic nor poisonous," this
is disputed. Exposure to fly ash through skin contact,
inhalation of fine particle dust and drinking water may
well present health risks. The National Academy of
Sciences noted in 2007 that "the presence of high
contaminant levels in many CCR (coal combustion
residue) leachates may create human health and
ecological concerns".[1]
Exposure to crystalline silica like that in fly ash is known
to cause lung disease, in particular silicosis.
Another fly ash component of some concern is lime
(CaO). This chemical reacts with water (H2O) to form
calcium hydroxide [Ca(OH)2], giving fly ash a pH
somewhere between 10 and 12, a medium to strong
base. This can also cause lung damage if present in
sufficient quantities.
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CONCLUSION
Fly ash utilization has great potential to lower green house
gas emissions by decreased mining activities and reducing
carbon dioxide production during manufacture of materials
that can be substituted by fly ash. Utilization of fly ash is
beneficial not only from environmental considerations, but
also to avoid land usage for fly ash dumping. Though
there has been a steady progress in fly ash utilization
from 1990, we have a long way to go to reach the target
of 100 per cent fly ash utilization. Fly ash can become a
wealth generator by making use of it for producing ‘green
building’ materials, roads, agriculture etc. Full utilization
of the generating stock will provide employment potential
for three hundred thousand people and result in a
business volume of over Rs.4,000 crores.
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RESULT
PropertiesofFly ash Bricks Comparedto ClayBricks
Common Load Bearing Clay Load BearingFly ash Bricks
Bricks
Factory location On site of raw materials Anywhere,preferablyonsite
of coal powerstation
Factory location Must change whenmaterial No change needed
depletes
Excavation needed required None
Raw materialsqualities Variesdaily consistent
Raw material neededper 4-5 tonnesof clayand shale 2.75 tonnesof flyash
1000 bricks
Raw materialswastage per 1.7-2 tonnesof clayand shale None
1000 bricks
Grindingof rocks required None to grind
Mixingdry materials required None
Additive (subjectto None Required@0.2L/100 kg
provisional confidentiality)
Drying greenunits 7 days 3 days
Temperature of firingthe 1000o
C- 1300o
C 1000o
C- 1300o
C
units (1832 F-2372 F) (1832 F-2372 F)
Length of firingtime 1day-7 days Few hours(subjectto
provisional confidentiality)
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Brick Type
Compressive
Strength
Modulusof
Rupture
Absorptio
n(IRA)
Absorpti
on
Capacity
Aver
age
Dens
ity
ClayBricks
Typical isfrom12 to 40
MPa. (1740 psi – 5800
5800psi)
From lessthan1
MPa (145 psi)to
greaterthan 2 Pa
MP 290 psi).
Default
value is0.8
MPa
(116 psi)
Typical range
between0.2
and 5
kg/m2
/min.
(5.9-147.5
lb/in2
/min)
5-20%
1800-2000
kg/m3
(112-125
lb/ft3
)
FlashBricks
43 MPa 10.3 MPa 4.5 kg/m2
/min 10%
(6235 psi) (1494 psi) (133 lb/in2
/min)
10.3 MPa
(1494 psi)
4.5 kg/m2
/min
(133 lb/in2
/min)
10%
1450 kg/m3
(91 lb/ft3
)
Samplesof the
bestclay bricks
34.8 MPa
(5046 psi)
3.6 MPa
(522 psi)
5.9
kg/m2
/min
(174 lb/in2
/min)
6%
2000 kg/m3
(125 lb/ft3
)
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REFERENCES:
Eco-friendly Techniques developed at Central Road
Research Institute ,India
Headwaters resources, “Fly ash for concrete”
N.Bhanumathidas and N.Kalidas, “ Fly ash: The
resource for construction industry”, Indian Concrete
Journal ,April 2003
Sciencedirect.com
Wikipedia
wealthywaste.com