Executive Summary : | Objective: To develop the formulation for mosaic/concrete tiles (flooring/wall) and paver blocks; To develop the formulation for Autoclaved aerated concrete; Scale up of the developed proccess up to pilot level Summary: Marble is a metamorphic rock resulting from the transformation of pure lime stone. There are around 4000 marble stone mines, 1200 marble cutters and 400 Automatic Tiling Plants spread all over the 20 districts (out of 33 districts) of Rajasthan. The major deposits of marble stone are Rajsamand- Udaipur - Chittorgarh region, Kishangarh- Makrana (Ajmer) region, Dungarpur- Banswara region, Jhiri (Alwar)- Andhi (Jaipur) region, Sirohi and Jaisalmer region. According the Department of Mines and Geology, Rajasthan; each year, about 6-7 MT (Production :13-15 MT) per year of marble stone is being generated out of 3600-3700 marble mining leases which poses major environmental and ecological problems such as –.
Choking of drains in rainy season
Dust nuisance
Fine particles of slurry (with size less than 363 micron) getting air borne and causing air pollution.
Slurry affecting productivity of land due to decreased porosity, water absorption and percolation.
Slurry dumped areas unable to support vegetation and remaining degraded (Fig. 1)
Due to long-term deposition of slurry on land, finer particles blocking the flow regime of aquifers, thus seriously affecting underground water availability
chemical composition is 28 – 35% CaO, 3-25 % SiO2,10 – 14%, MgO, 1 –2.5% R2O3, 15 - 20% Acid insoluble and 35 – 40% Loss on ignition with traces of Titanium Oxide and Lead. This waste can be used for making value added product for different building applications. As per literature, it has been seen that the replacement of waste marble with cement or aggregate in conventional concrete has improved properties of hardened concrete. But, replacement depends on the aggregate crushing strength, aggregate impact value, aggregate abrasion resistance, size & shape of aggregates with their angularity as on site by site basis. So, it is not typical that same mix proportion will be applicable to the waste aggregate of different sites. Severe problems of disposal of this huge waste are being faced by marble stone industry. There is no law to prevent the industries for dumping the waste in this haphazard manner. Slurry is identified as a hazardous waste by the Rajasthan Pollution Control Board. Therefore, it is very much interested to make out its use through development of value added product out of it for building applications. |
