Environmental Analysis on Co-Processing of Domestic Waste in Cement Kiln

The annual output of domestic waste has exceeded 400 million tons in China since 2016, which causes an urgent demand on harmless disposal in the current rapid process of urbanization. Compared with traditional disposal means (e.g. incineration and landfill), co-processing with cement production seems to be a better chose to meet the requirements of domestic waste treatment (i.e. harmless, volume reduction, waste utilization). However, co-processing technology also has some negative impact (e.g. extra energy consumption for pretreatment of domestic waste), so the environmental feasibility of domestic waste co-processing in cement kiln should be verified. In this paper, the influences caused by domestic waste co-processing on the cement clinker products including resource/energy consumption, as well as the pollutant emissions were quantify based on the investigation of typical plants in China. Moreover, the environment impact between landfill treatment and co-processing scenario were compared using life cycle assessment (LCA) method. The result shows that the energy consumption and CO2 emission per ton cement clinker production increased by 3.6% and 0.8% after co-process domestic waste, respectively. Furthermore, compared with sanitary landfill treatment, the co-processing in cement kiln will increase the impact of FFP, but reduce GWP and HTP impacts, especially significantly decrease the impact of LOP and SOP, bring in a good beneficial on material saving and energy saving.