Executive Summary : | Objective: Procurement and characterization of raw materials; Development of hemihydrate plaster (POP) suing FGD gypsum as per Indian standard; Development of water resistant high strength plaster using FGD Gypsum & Fly ash for use in buildings (both internal & external walls, floor etc.); Evaluation of physical and mechanical properties of the developed products; Durability studies of high strength plasters; Cost Estimation and writing of final report; Transfer of the technology for commercial exploitation. Summary: With exponential increase in population, urbanization as well as Continuous improvement in standard of living, demand of natural resources and energy has increased many folds. Massive requirement of concrete for infrastructural facilities in developing countries has created a pressure on cement and construction industry due to lack of the natural resources. Further, with advancement in science, technology and industrial revolution, the environmental pollution has assumed alarming proportions in the developed and the developing countries. The gaseous and the liquid effluents from these industries are degrading the environment and posing a hazards to both human and animal life and thus causing concerns for their disposal. Due to indiscriminate disposal trends, large areas of fertile land have become barren and unproductive for agricultural purpose. Efforts are, therefore, being made throughout the world to effectively recycle these industrial wastes. Phosphogypsum from the phosphatic fertilizer plants, fly ash from thermal power plants, flue gas gypsum from power plants, fluorogypsum produced from hydrofluoric acid industry and lime sludges from sugar, paper & acetylene units, slag from iron & steel, red mud from aluminum based industries etc. are the paramount industrial agricultural wastes of great interest. These waste materials contain harmful impurities which interfere with the setting & hardening of the cements & cementitious materials, and other building materials produced from them. Flue gas desulfurization (FGD) gypsum is produced from the desulphurization of combustion gases of fossil fuels, such as anthracite, bituminous coal, lignite and oil in large combustion plants like power plants. Burning of coal in power plants produces harmful flue gases like CO2, NO2, and SO2. To reduce the SO2 emission to the atmosphere, several flue gas desulfurization processes had been developed. Wet-type scrubbing process and dry or semi-dry scrubbing processes are generally two scrubbing methods used for desulphurization. Among these methods wet-type scrubbing process was most widely used (90%). In this process lime stone is used as a sorbent and the SO2 is converted to gypsum (CaSO4.2H2O). In India, fly ash is also generated from thermal power plants about 25 MT of fly ash is generated per annum. About 40 % fly ash utilized in cement manufacturing, cement and concrete, fly ash bricks/blocks, road etc. Fly ash is a pozzolanic material which gives cementing properties when added with water in presence of lime. It can be used as additive for development of water resistant high strength binder. Beside this, vermiculite/perlite may be used as mineral admixture as pozzolanic material for development of high strength water resistant binder. To overcome the fugitive dust emission problems during transportation, specially designed Road Tankers/ Bulkers or mechanically designed covered Trucks provided with automatic loading and unloading through compressor / vacuum pumps mounted on the tankers will be used. Tractor trolleys with box type cover on top with hydraulic unloading system may be deployed for transportation of dry or wet materials, while trasporting through habilitated areas otherwise, Tractor trolleys suitably covered with good quality of tarpaulin (made of HDPE) can be used to transport for shorter distance say upto a distance of about 10 Kms.
Installation of Bag Filters with dry collection and storage in Silos at loading and unloading points will be recommended at both locations i.e. loading at power plant site as well as at the unloading point at user’s site. |