Impact of internal conditions on the gas flow path in semi-aerobic landfill reactors

Despite the continuous development of waste disposal technology, landfill remains a significant means of municipal solid waste disposal around the world. Accelerating the process of waste stabilisation has become a pressing problem. In this study, four indoor landfill reactors were set up. Reactors A and C were semi-aerobic landfills, and in reactors B and D the gas vents were disconnected from the leachate collection pipes. Kitchen waste was the main ingredient of the sample waste (55.46%). The void fractions of reactors C and D were decreased by adding extra gravel. The void fractions were 32.82% and 33.27% in reactors A and B, respectively, whereas those in reactors C and D were about 6% lower. The temperatures of reactors A and B were higher than those of reactors C and D. The temperature peak in reactor A occurred earlier than that in Reactor B. The temperature and gas concentration measurements confirmed that not all the air was discharged directly through the gas vent, and some air passed horizontally through the waste layer of the reactor. It was finally showed that the void fraction and connections in the pipelines inside the landfill reactor affected the gas flow path.