Enhanced methane recovery by food waste leachate injection into a landfill in Korea

The current food waste leachate (FWL) disposal practice in Korea warrants urgent attention and necessary action to develop an innovative and sustainable disposal strategy, which is both environmentally friendly and economically beneficial. In this study, methane production by FWL injection into a municipal solid waste landfill with landfill gas (LFG) recovery facility was evaluated for a period of more than 4 months. With the target of recovering LFG with methane content ∼50%, optimum LFG extraction rate was decided by a trial and error approach during the field investigation in five different phases. The results showed that, upon FWL injection, LFG extraction rate of ∼20 m3/h was reasonable to recover LFG with methane content ∼58%. Considering the estimated methane production potential of 31.7 m3 CH4 per ton of FWL, methane recovery from the landfill was enhanced by 14%. The scientific findings of this short-term investigation indicates that FWL can be injected into the existing sanitary landfills to tackle the present issue and such landfills with efficient liner and gas collection facility can be utilized as absolute and sustainable environmental infrastructures.

► Feasibility of FWL (a liquid organic waste) injection to a landfill is investigated.
► Optimum LFG extraction rate was decided by a trial and error approach.
► LFG recovery at the rate of ∼20 m3/h with ∼58% methane was possible.
► Methane recovery was increased by 14% upon FWL injection to the landfill.