On August 29, a man in Hancheng City, Weinan, Shaanxi Province, released a real-name video, reporting that a local resource recycling enterprise violated the rules of construction and destroyed the environment, causing a total of 700,000 tons of mixed solid waste, including fly ash, domestic waste, construction waste and industrial waste, to flow into the Yellow River. It is better to use cement kilns to co-dispose of solid waste
than to put it into rivers to endanger the ecological environment. Cement kiln co-processing can not only replace part of raw materials and fuels, reduce energy and resource consumption, but also reduce environmental pollution and health damage to residents through waste treatment. At the same time, it can save land resources, promote the green and low-carbon transformation and development of cement enterprises, realize the recycling, harmlessness and reduction of solid waste, and beautify the urban living environment.
Cement kiln co-disposal of solid wastes refers to the process of putting solid wastes that meet the requirements of entering the kiln or meet the requirements of entering the kiln after pretreatment into the cement kiln, and realizing the harmless disposal of solid wastes while producing cement clinker.
Cement kiln co-processing of industrial solid waste has strong advantages. It is understood that compared with the current conventional waste incineration and other disposal methods, the same is incineration, the temperature of the waste incinerator is only eight or nine hundred degrees Celsius, the temperature is relatively low, easy to produce dioxins. Cement kiln material melting can reach 1450 degrees Celsius, and the gas produced can reach 1700 degrees Celsius. In the case of high temperature gas, urban garbage, sludge and hazardous waste will be decomposed, and it is not easy to produce dioxins. In addition, cement kiln is an alkaline environment, which can effectively absorb a lot of gases, and the emission of harmful gases is less. Moreover, heavy metals can be effectively wrapped in the burning process of cement clinker without causing secondary pollution.
In addition, the statistical analysis shows that if the 5000t/d cement clinker production line co-processes domestic waste, the disposal scale is 400t/d, the coal consumption per ton of clinker will be reduced by about 5%, the power consumption will be increased by 2.7 ~ 5.3 kW · H, and the CO CO emission per ton of clinker will be reduced by about 10.8kg. If the 5000t/d cement clinker production line adopts 60% carbide slag batching, the CO CO emission per ton of clinker will be reduced by 227.5kg. If the 5000t/d cement clinker production line co-processes municipal sludge, the disposal scale is 500t/d, the coal consumption per ton of clinker will be reduced by about 6 kg, the power consumption will be increased by 3 kW · H, and the CO discharge per ton of clinker will be reduced by 11.5 kg.
Cement industry is the most suitable industry for co-processing of hazardous wastes. Promoting the application of cement kiln co-processing solid waste technology can not only effectively solve the current problems of solid waste treatment, but also bring new development opportunities for the cement industry.
