Cement Energy Environment

53 Thermal energy efficiency 3% CO2 capture ,utilisation & storage(CCUS) 25% Innovative technologies(exclud ing CCUS) 23% Fuel switching 12% reduction in clinker to cement ratio 37% CUMULATIVE DIRECT CO 2 EMISSION REDUCTION (GT) production (950 kg/t clinker), now if Clinker factor is reduced to 35% like in case of Portland Slag Cement where clinker factor is only35% then the total CO 2 count stands 235 only (950-390=560, 35% equal to 196+40 (for Grinding power) hence total 236 kg/t cement is possible. The detailed paper deals with all these developments in details and steps ahead. The global production of cement has currently reached 4.2 Gt in 2020 with core production in India as 329 MT which accounts for nearly 8% of Global Production. The cement production capacity in India is estimated to touch 550 MT within span of 2020-22. As far now the main producer still remains China which accounts nearly 55% of the production capacity. Depending on the current situation and the decreasing pandemic devastation rate the market is expected to grow in the forthcoming decades up to 12–20% by 2050, on account of population and urbanization trends, coupled with infrastructure development needs. As widely known the cement sector is one of the major sources of anthropogenic CO 2 , accounting for 8% of global emissions with every 0.95 t of CO 2 released per tonne of cement produced. The actual carbon footprint depends on the ratio of clinker to cement, the manufacturing process, heat consumption and heat recovery, the fuel used, the moisture content of the raw materials, capacity of the plant, optimised operations and advanced technologies for insitu inhibitions of the direct pollutants. Process emissions account for approximately 65% of the direct CO 2 emissions, whereas fuel combustion is responsible for the remainder .Total CO 2 emissions have increased by 200% since early 90s due to growth in cement demand proportionate to urbanisation. Although the decrease in the global average clinker ratio, improvement on energy efficiency, and increased usage of alternative fuels have played a significant role in curbing the pollution ,usage of coal still remains the dominant factor with a share of 65% of the total fuel consumption level by Cement Industry. On the other hand, the net climate impact of concrete products needs to account for the fact that 11–43% of the initial process emissions may be offset by gradual reabsorption of atmospheric CO 2 by the exothermic carbonation of hydrated cement. With the aim to limit global warming to 2°C above pre-industrial levels and to pursue efforts to restrain it to 1.5°C it is necessary to decarbonise the cement industry at a global scale. There is a series of mitigation measures that can contribute to the decarbonization of the cement industry: improving energy and materials efficiency (on a life cycle approach); switching to less carbon intensive fuels; reducing the clinker content in the cement by partly replacing it with cementitious materials with lower carbon footprint; developing new, innovative and clean production technologies, including waste heat recovery (WHR) to power generation, integration of renewable power generation,CCUS; and improving transport efficiency. As shown in Figure 1, highest contribution for achieving less comes from the reduction in the clinker ratio, followed by CCUS, development of clean production technologies, fuel substitution, and thermal efficiency. A detailed approach to these with possible explanations follow in the coming sections of the paper.