Cement industry is regulated by legislation in which various measures are specified for prevention and reduction of air pollution as well as protection of human health, due to atmospheric emissions, which occur during cement production. Legislation also holds emission limit values for co-incineration of wastes i.e. alternative fuels. Waste tires as an alternative fuel can be co-incinerated i.e. co-processed in cement plants, where the high calorific value of the rubber is used to substitute fossil fuels and the mineral part to substitute the raw materials. By combustion of waste tires flue gases occur, which leads to atmospheric emissions. The question is, if use of waste tires leads to higher emissions to air and with that higher risk to human health. Fort his purpose the entire cement production process is described as well as the clinker burning process, which covers the burning of waste tires in the HOTDISC combustion device. Furthermore, the composition of waste tires and calorific values are presented comparing to fossil fuels, such as coal and petcoke. Also values for emissions during a certain period are given, which were obtained with permanent and occasional measurements. Based on production process, feed point of waste tires, conditions in HOTDISC combustion device and gethered data, various examples and conclusions are given about the impact of co-processing waste tires in cement plant on the emissions to air and to human health.
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