Causation mechanism analysis of excess emission of flue gas pollutants from municipal solid waste incineration power plants by employing the Fault Tree combined with Bayesian Network: A case study in Dongguan

Abstract

As municipal solid waste incineration (MSWI) gradually became the mainstream treatment for MSW in China, some backward MSWI power plants caused severe environmental problems of excess emission of flue gas (FG) pollutants and aroused wide concern. For analyzing the causation mechanism about excess emission of FG pollutants from MSWI power plants (top event/leaf node) in China, an efficient risk evaluation framework is established in this work. Correspondingly, an exploratory classical Fault Tree and Bayesian Network model is developed for the first time for the excess emission of FG pollutants of MSWI power plants. To figure out the key risk factors associated with the occurrence of top event/leaf node, several real MSWI power plants in Dongguan, representing advanced (Plant B), general (Plant A2), and outdated (Plant A1), are taken as case studies. After the analysis, compared with Plant B, the occurrence probability of the top event/leaf node in Plant A1 and A2 is 0.81724 and 0.44720. The key risk factors are determined as: “Outdated FG treatment process (X4)”, “Complex composition of MSW (X1)”, “Incineration technology defect (X6)”, “Aging of FG treatment equipment (X8)”, “Insufficient maintenance of FG treatment equipment (X9)” and “Aging of incineration equipment (X7)”. This work may provide a novel perspective to the environmental risk evaluation for the excess emission of FG pollutants from MSWI power plants in China, which also can offer cleaner production decision support for FG pollutants reduction in the MSWI industry.