파일롯 규모 바이오커버에 의한 생활폐기물 매립지의 휘발성유기화합물 제거

Abstract

A pilot-scale biocover was installed at a sanitary landfill for municipal waste, and the removal of volatile organiccompounds (VOCs) by the biocover was evaluated for a long period of 550 days. The biocover (2.5 m W × 5 mL × 1 m H) was constructed with the mixture of soil, perlite, earthworm cast and compost (6:2:1:1, v/v). The totalVOCs concentration of the inlet gas into the biocover was 820.3 ppb~7,217.9 ppb, and the total VOCsconcentration of the outlet gas from the surface of the biocover was 12.6 ppb~1,270.1 ppb. The average removalefficiency of total VOCs was 87.6 ± 11.0% (60.5% for minimum and 98.5% for maximum). Toluene concentrationwas the highest among the inlet VOCs, followed by ethylbenzene, m, p-xylene and o-xylene. These aromatic VOCsaccounted for more than 50% of the total VOCs concentration. Other than these aromatic VOCs, hexane,cyclohexane, heptane, benzene, and acetone were major VOCs among the inlet VOCs. Compared with the VOCprofiles in the inlet gas, the relative contribution of dichloromethane to the outlet VOCs emitted from the biocoverlayer increased from 0.1% to 15.3%. The average removal efficiencies of BTEX in the biocover were over 84%during the operation period of 550 days. The average removal efficiencies of hexane, cyclohexane and heptanein the biocover were 86.0 ± 18.9%, 85.4 ± 20.4% and 97.1 ± 4.0%, respectively. The removal efficiency of VOCsin the biocover decreased not only when the ambient temperature had fallen below 5oC, but also when the ambienttemperature had risen above 23oC. Information on the VOCs removal characteristics of the biocover installed inthe landfill field can be useful for commercializing the biocover technology for the treatment of VOCs.