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Bohra A.,National Council for Cement and Building Materials | Nema A.K.,Indian Institute of Technology Delhi | Ahluwalia P.,Tata Consultancy Services Ltd.
International Journal of Environmental Technology and Management | Year: 2012

Municipal solid waste in developing nations like India is an area of major concern. The concerns associated with waste management are not only public health and safety but also for sustainable development. Life cycle assessment (LCA) can be applied to assess the environmental sustainability of waste management systems. In the present study, global warming potential of various municipal waste management options was evaluated using LCA. The model was applied for a case study of Delhi (India). From the results of the study, it was found that the scenario of maximum diversion from sanitary landfill results in least impact to global warming. © 2012 Inderscience Enterprises Ltd. Source

Bhaumik A.K.,Indian School of Mines | Gupta A.K.,Indian Institute of Technology Kharagpur | Gupta A.K.,Wadia Institute of Himalayan Geology | Clemens S.C.,Brown University | Mazumder R.,National Council for Cement and Building Materials
Current Science | Year: 2014

Morphometric study of Melonis barleeanum and Hoeglundina elegans was carried out on 15 core top samples from the Indian Ocean. Length to breadth ratios and wall and septal thicknesses of the largest tests of both the species from each sample, along with δ13C and δ18O values of Cibicides wuellerstorfi were measured. Both the species show equal growth rates of the test in their normal habitat. However, the high organic carbon preference species M. barleeanum shows more elongation of the test during food scarcity. This effect is not evident in H. elegans, which varies in its wall and septal thicknesses with bottom-water oxygen levels of the deep water mass up to 2000 m, probably to maintain the required rate of osmosis for the intake of dissolved O2. Below this depth both parameters show parallel relationship with deviation indicating that oxygenation may play some role in the variation of wall and septal thicknesses. Thinning or thickening of the wall and septa in M. barleeanum and H. elegans has no relation with the water depth, indicating no relation with either the overlying pressure effect or nutrients as each deep water mass has a different nutrient budget. Depletion in δ13C and enrichment in δ18O below 2000 m water depth suggests that up to 2000 m depth, the Indian Ocean is bathed by the welloxygenated, low-nutrient North Atlantic Deep Water (NADW), whereas below 3000 m cold, nutrient-rich Antarctic Bottom Water (AABW) is dominant. Between 2000 and 3000 m water depths, the water mass in the Indian Ocean is a mixture of NADW and AABW. Source

Pahuja A.,National Council for Cement and Building Materials | Ali M.M.,National Council for Cement and Building Materials
Cement International | Year: 2013

In recent decades the global needs and concerns in the areas of energy, GHG emissions, conservation of natural resources and preservation of the environment have resulted in application-oriented developments in the fields of cement, concrete and other cementitious materials. The National Council for Cement and Building Materials (NCB), which guides the affairs of the Indian Cement and Construction industries, is uniquely positioned to provide technological improvement and technical support services, sustainable development and growth for the industries. Some of the noteworthy research work where the NCB has made great progress includes clinker formation under the influence of fluxes, modifiers and mineralizers, increased utilization of fly ash in PPC by mechanical, chemical and thermal activation, exploration of the potential for utilization of low grade limestone and non-conventional slags from zinc, copper and other industries in cement, increased use of alternative and waste-derived fuels, increased energy efficiency by de-bottlenecking process lines, life cycle studies, etc. The other important services rendered are development of standard reference materials, test methods and building codes along with pioneering technologies such as geopolymers, composite cements, the application of nano technology in cement and concrete, and high performance concrete. The advances achieved in the cement and concrete sectors would not have been possible without the improvement in the quality of human resources carried out by the NCB through its dedicated and tailor-made training modules. These have been made possible through the availability of multi-disciplinary expertise at the NCB, coupled with world class testing and evaluation facilities at its Ballabgarh, Hyderabad and Ahmedabad units. The achievements of the various NCB centres are described below. Source

Ali M.M.,National Council for Cement and Building Materials | Chaturvedi S.K.,National Council for Cement and Building Materials | Sharma P.S.,National Council for Cement and Building Materials
Cement International | Year: 2011

In the last decade, global needs and concerns in the areas of energy, GHG emissions, conserving natural resources and preserving the environment have resulted in application oriented developments in the field of cement, silicates and other cementing materials. In this pursuit, besides conventionally used fly ash and granulated blast furnace slags, various other industrial wastes and by products such as spent pot linings, non ferrous slags, refinery wastes, etc. have been investigated and have shown potential for beneficial use. Fly ash have been also investigated for use in sintered light weight aggregates and concrete, cement/silicate bonded fly ash/clay fly ash building bricks, precast fly ash concrete building units, cellular concrete, bricks and blocks, lime and cement fly ash concrete, structural fill for roads, construction sites, land reclamation etc., as a filler in mines, as a filler in bituminous concrete and manufacture of insulating and semi-insulating bricks, as a plastisizer and a pumping aid, as a water reducer in concrete, sulphate resisting concrete and as a filler in paints and pigments. While fly ash can find usage in many other areas as well, the use in PPC and in concrete still remain the biggest user segment of fly ash with the PPC production level reaching to ∼100 million tonnes during 2009-10 amounting to more than 62 percent of total cement production in India. Diversifications in the use of raw materials, fuel, industrial wastes and basic research findings to conserve energy in cement manufacture and generate special properties have resulted in development of jet set fluoroaluminate, expansive, oil well, alkaline, dental, nuclear and photo chromic cements. These developments were based on modifications or additions in the chemistry of Portland Cement. In the field of nuclear research, the shielding of radiation and fixation of disposal wastes need cements and development of barium aluminate and other products was quite a success. Further, the production of Portland limestone cement (PLC) is described as a fast and economical technical solution for cement industry around the world. Geo polymer cement is another area of importance as it provides the opportunity for both waste beneficiation/valorisation and immobilization, while providing an alternative to a highly polluting existing technology. The future of R&D in the area of cement and building materials will revolve around development of cost effective, consumer friendly and high performance materials based on Nano-Technology. This is one area which needs systematic and through investigations and shall generate benefits of exponential order. Source

Ali M.M.,National Council for Cement and Building Materials | Agarwal S.K.,National Council for Cement and Building Materials | Pahuja A.,National Council for Cement and Building Materials
Advances in Cement Research | Year: 2013

The addition of copper oxide in cement raw mix is known to improve its burnability, with increase in formation of the alite phase. Copper slag, a by-product of the metallurgical industry, containing copper oxide can therefore be a useful additive in the manufacture of cement, particularly for hard burning raw mixes. This paper presents a study on the effect of addition of 1.5-2.5% of a typical by-product copper slag sample to cement raw mixes prepared from two different limestone samples, with free silica content of 5.52 and 10.97% and average grain sizes of 124 and 175 μm. The clinker parameters such as limestone saturation factor, silica modulus and alumina modulus were in the ranges 0.91-0.92, 2.11-2.29 and 1.0-1.20, respectively. The fineness values of the raw mixes were 3.50-4.20 and 20.80-21.34% retained on 212 and 90 μm sieves, respectively. Burnability studies of these raw mixes were conducted at temperatures of 1300, 1350, 1400 and 14508C, with retention time of 20 min, and showed increase in the rate of lime assimilation, acceleration in the formation and growth of C3S and lowering in clinkerisation temperature by 508C. The free silica was found to be completely assimilated at 14008C in mixes containing copper slag. The mineral phase developments and microstructures of laboratory clinker samples fired at 1400 6 58C were comparable to control clinker prepared at 1450 6 58C. Physical properties of ordinary Portland cement prepared using this clinker showed performance comparable with control cement. The copper slag contains heavy elements, therefore a leaching study was also conducted by immersing hardened cement pastes in distilled water for 6 months. The leachates, such as barium, copper and chromium, were found to be 0.032, 0.005 and 0.031 ppm, indicating fixation of these elements in the clinker mineral phases. Source

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