Cement, Energy and Environment

30 for the other alternatives to be used as raw material and additives. Parallely increased use of blended cement also leads to the concepts of co-utilization. Everything comes with a price but advancement and success lies in the technological innovations which are effective and cost competitive also. 3.0 Energy: Definition, Concept & Measures With rising input costs of cement production day by day, the bottom line of the cement production is always subjected to challenges for improvement. The cement industry is said to be an energy- intensive industry together with steel, paper and petrochemical industries. Energy cost is the major component of the input costs of cement manufacturing. Energy for cement industry consists of both thermal and electrical energy. Energy conservation involves improving the energy efficiency by consuming the minimum possible energy using technological developments. Energy cost reduction also involves using other cheaper energy sources such as cheaper fuels, waste heat recovery systems, thermal power plants, solar panels etc. Energy conservation measures include both short and long term solutions. These solutions will be specific to each cement plant of different production capacities with different types of main machinery. The Perform, Achieve and Trade (PAT)launched by the Bureau of Energy Efficiency under the Ministry of Power, Government of India, offers an opportunity to the industry to improve its energy efficiency and reduce energy consumption resulting in long term economic benefits in terms of reduced fuel expenditure with trading. 3.1 Electrical Energy Consumption: Roller Presses are definitely the solution for grinding circuits which consumes nearly 65% of electrical energy in cement production process. Comflex Grinding system from KHD consumes less energy compared to other process circuits and is a proven fact for raw material and slag grinding. In case of clinker grinding application also, less specific power is established with Roller Press in finish mode operations as compared to other technologies available at present. Some of the operating results which are shared in next section depict the energy efficiency of Roller Press. Talking about the Pyroprocess system the solutions from KHD are definitely lower in power due to reduced pressured drops, efficient cooler and less radiation losses across the equipments 3.2 Thermal Energy Substitution: The utilization of alternate fuel in Indian Cement Industry is at low level at present; the country average stands at less than 2 % of thermal substitution rate (TSR) compared to average TSR of about 40% in European Cement Industry. Usage of alternate fuel can be enhanced through a concerted effort of characterization and evaluating various types of Waste Derived Fuel (WDF) and establishing their suitability for use in Cement manufacture. Development of data base on availability and characterization of combustible waste and waste derived fuels and evaluation of International best practices and technology for waste management and utilization and their adaptation for Indian Cement Plant will also be helpful. Indian Cement Industry has lot of potential to use alternate fuel in the manufacture of cement with benefit in terms of conservation of natural resources and prevention of environmental hazards including mitigation of greenhouse gas emission, all of which serves the goal of sustainable growth and development in India. Industrial and mineral wastes from mineral processing industries, such as metallurgy, petrochemical, power, chemicals, paper and pulp accounts for more than 200 million tons out of which more than 6 million tons are hazardous and can be used alternatively in cement kilns. Keeping in view, long time back KHD has rolled down equipments to control the environment and curb the emissions. One such example is of combustion chamber. KHD Combustion chamber is especially designed to burn the material which is lumpy and coarse in nature as well as difficult to ignite. The Calciner process is ruled by the classical dilemma, that temperature and oxygen levels need to be reduced to the maximum in order to increase production at reduced heat consumption and emission levels while a complete burn-out is still required to avoid CO-triggered failures. Adding to the difficulty, increasingly more often secondary fuels of lumpy size and sometimes problematic combustion properties are fired, which must be given sufficient retention time to burn out and must be kept clear from the bricklining as long as they are not fully burnt out. An optimized flow pattern of the gas- meal-fuel suspension within the vessel is necessary to accomplish that without creating excessive calciner dimensions. The Calciner design is based on the requirements of Creation of subsequent zones with dedicated functions for a controlled process of NOx Reduction, staged combustion and Mixing zone for a reliable final oxidization on CO- remains.