폐기물의 기계적-생물학적 전처리기술

Abstract

Landfilling of untreated municipal solid waste (MSW) results in adverse environmental impacts such as emission of landfill gas, generation of leachate, and long-term settlements. When MSW is landfilled without pretreatment, landfill gas emissions may occur for a long period of time (up to 100 years). In order to reduce landfill emissions to a minimum, waste should be pretreated. The mechanical-biological pretreatment (MBP) of residual wastes before landfill is applied to several countries in Europe. The MBP is suitable for the pretreatment of wastes and considerably reduces gas emission and leachate generation by aerobic or anaerobic microbial decomposition. We mainly introduced the concept and process of MBP and landfilling of residual waste after MBP. MBP has the following effects on MSW: (1) homogenization and reduction of weight and volume; (2) reduction of biodegradable components and biological stabilization; (3) reduction of gas emission potential and of leachable generation; (4) increase of bulk-, landfilling- and storage density of waste; and (5) reduction of the hydraulic conductivity and gas permeability. Although there are several advantages of MBP, one of the major disadvantages of MBP is a high build-up of surface water. As MBP-treated MSW has high density, its permeability is low, so that small ponds may form on the surface after heavy rainfall. The MBP-treated MSW is quite different from raw MSW. As a consequence, it is important to investigate these new landfill concepts. The major objective of MSW pretreatment is to mitigate pollutant emitted from landfill. MBP can considerably reduce landfill gas and leachate production. Therefore, there is a significant need to consider introduction of MBP in Korea.