Evaluation of the efficiency of an experimental biocover to reduce BTEX emissions from landfill biogas

• Landfill is a source of volatile organic compound (VOC) emissions.
• Biocover efficiency reduce VOC emissions from 67% to 100%.
• Biocover is an interesting method to reduce VOC emissions.

Landfill emissions include volatile organic compounds (VOCs) and, particularly, benzene, toluene, ethyl-benzene and xylene isomers (collectively called BTEX). The latter are the most common VOCs found in landfill biogas. BTEX affect air quality and may be harmful to human health. In conjunction with a study aiming to evaluate the efficiency of passive methane oxidizing biocovers, a complementary project was developed with the specific goal of evaluating the reduction in VOC emissions due to the installation of a biocover. One of the biocovers constructed at the Saint-Nicéphore (Quebec, Canada) landfill site was instrumented for this purpose. The total BTEX concentration in the raw biogas ranged from 28.7 to 65.4 ppmv, and the measured concentration of BTEX in biogas emitted through the biocover ranged from below the limit of detection (BLD) to 2.1 ppmv. The other volatile organic compounds (OVOCs) concentration varied from 18.8 to 40.4 ppmv and from 0.8 to 1.2 ppmv in the raw biogas and in the emitted biogas, respectively. The results obtained showed that the biocover effectiveness ranged from 67% to 100% and from 96% to 97% for BTEX and OVOC, respectively.