An integrated plant for municipal solid waste co-combustion in cement production

This paper presents a novel and highly integrated design of cement and electricity production by co-combustion of municipal solid waste (MSW) and fuel. By tightly integrating the three processes, energy generated from the co-combustion can be effectively utilized for cement production and electricity generation. This synergy also results in significant reduction in new pollutant emissions. Solid wastes such as fly ash from the combustion can be used as feedstock for cement production. The raw material of cement production such as lime (CaO) works as an adsorbent for converting polluting gas such as SOx generated from the combustion to components of cement such as calcium sulfate (CaSO₄). The reduction of chlorine compounds in the combustion process plays a key role in managing dioxin formation from the combustion process. Lime again is good adsorbent for chloride to prevent it from being converted into dioxin during the high temperature process. Using the heat generated from the combustion process, wooden wastes sorted from MSW can be converted into active carbon that is a ideal adsorbent for dioxin in the downstream air pollution control processes of the waste gases. The large amount of lime used in cement production and the low-cost active carbon cleanup the waste gases in the most economic and effective way, These three processes are perfectly integrated reducing overall energy consumption and pollution. An integrated pilot unit is being built in Hong Kong and will be ready for operation by the end of year 2002.