Improving profitability in cement production by cutting energy costs and emissions
A growing number of cement production plants around the world are reducing energy costs, cutting emissions and improving environmental performance by replacing fossil fuels with alternative fuels made of municipal solid waste and commercial and industrial waste.
Cement producers utilizing alternative fuels such as refuse derived fuel (RDF) and solid recovered fuel (SRF) can gain a substantial competitive edge if the alternative fuel meets the required standards. In many cases, however, input waste streams contain diverse materials not suitable for co-processing in the cement kiln.
A well-designed alternative fuel production process ensures the optimal quality. To maximize the energy production with the lowest possible emissions, homogenous grain size, high calorific value, controlled material composition, the removal of fines, low chloride and a stable humidity content are a must.
Effective pre-shredding removes unwanted items so they do not contaminate the final fuel product. For RDF and SRF production, light materials like plastic products and other dry combustibles are useful, while rocks, cement lumps, sneakers, boots, wet newspapers and metals reduce the calorific value.
Opening waste bags and reducing the size of waste by pre-shredding ensures that unwanted items can be screened and separated from the process. Later, when the material content of the alternative fuel content is optimal, fine shedding turns it into the right shape and size for combustion to maximize energy generation.