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Now-days, all over the world, construction activities are taking place on huge scale. Due to this there is great increase in cost of construction. Natural river sand is one of the key ingredients of concrete, is becoming expensive due to excessive cost of transportation from sources. Also large scale depletion of sources creates environmental problems. Unfortunately, production of cement also involves large amount of carbon dioxide gas into the atmosphere, a major contributor for greenhouse effect and the global warming. To overcome these problems there is a need of cost effective, alternative and innovative materials. Industrial by products are those which is coming from different industries other than the main proposed product. It can also called as a sub product of different processes coming in manufacturing. In recent days these products are recycled and reused for other purposes to reduce cost and problems coming from disposal. These are 50% more ch eaply than the original raw materials. In cement manufacturing process, a cement plant consumes 3 to 6 GJ of fuel per ton of clinker produced, depending on the raw materials and the process used. Most cement kilns today use coal and petroleum coke as primary fuels, and to a lesser extent natural gas and fuel oil. Selected waste and by-products with recoverable calorific value can be used as fuels in a cement kiln, replacing a portion of conventional fossil fuels, like coal, if they meet strict specifications.
Selected waste and by-products containing useful minerals such as calcium, silica, alumina, and iron can be used as raw materials in the kiln, replacing raw materials such as clay, shale, and limestone. Because some materials have both useful mineral content and recoverable calorific value, the distinction between alternative fuels and raw materials is not always clear. For example, sewage sludge has a low but significant calorific value, and burns to give ash containing minerals. Eco sand (finely graded silica) is a by-product coming from cement manufacturing process, mainly cement industries those use silica as a raw material is mainly producing eco sand as by-product.