Biological and Chemical Atmospheric Emissions of the Biogas Industry

Abstract

Actions of French governments on waste, resource and energy management force to focus on waste treatment and recovery process. Among these processes, anaerobic digestor offers significant advantages compared to other forms of waste treatment. It permits an organic waste treatment and a double valorization. The organic waste treatment enables the production of a digestate and a combustible gas fraction called biogas. The digestate, is an improved fertilizer, and can be enhanced by spreading or composting. Biogas can be valorized to produce heat or electricity. From this activity sector, energy production is expected to increase from 1,478 GWh in 2005 to 13,701 GWh in 2020 (Club Biogas ATEE, 2011). Anaerobic digestion is widely studied to understand its mechanisms at microbial level and to improve biogas production and process stability. However, health risk for workers in these facilities and for surrounding residents is very poorly documented. Gaseous and particulate emissions are also incompletely defined. Information on odor concentrations and biogas chemical /biological composition has been investigated. Nevertheless, no data on emissions from inputs storage locations or digestate was currently available. The EMAMET project aims to improve our understanding concerning the biogas production sector. Sources of gaseous and bioaerosol emissions will be researched and characterized on the whole production chain. The chemical composition of gaseous emissions will be completed by odor concentration determination. Biological emissions will be determined by molecular methods. From this information, specific biological and/or chemical indicators of this activity will be defined. In addition, 2D and 3D emission modeling will used to determine the influence zone of the biogas production implantation. To confirm this influence area a research of biological and microbial indicators around a pilot site will be realized. These data can help to assess health and environmental risks for workers and surrounding populations. This information is necessary to develop relevant sensors for control and monitoring of such emerging energetic processes.