Biogas Processing and utilization

A presentation on the properties, cleanup, processing, and utilization of biogas. Includes project results

Biogas Processing - Final Report

Anaerobic digestion offers an effective way to manage dairy manure by addressing the principal problem of odor and environmental control while offering an opportunity to create energy from the conversion of biogas with a system of combined heat and power (CHP). The use of biogas as an energy source has numerous applications. However, all of the possible applications require knowledge about the composition and quantity of constituents in the biogas stream. This study provides data on the composition of anaerobic digestion biogas (ADG) over time (hourly, daily, weekly and year), results from the use of dairy-manure compost as a biofilter to remove hydrogen sulfide H2S from the ADG, and an assessment of the feasibility of injecting ADG into the natural gas pipeline. Results agree well with the often quoted generalized concentrations of 60% CH4, 40% CO2 and 600 BTUs for dairy-derived biogas. They also show that, depending on additives to the dairy manure and quality of farm water supply, the H2S concentrations can vary substantially from less than 1000 ppm to well over 6000 ppm. Utilization of cow-manure compost for removal of H2S from AD biogas using small-scale reactors was studied and shows promise. A technical and economic assessment of processing of biogas for injection to the natural gas pipeline, while dependent on biogas quantity, price for processed biogas, proximity of the biogas producer to the natural gas pipeline and the interest rate, suggests that a real possibility exists for injecting biogas to the natural gas pipeline dependent, of course, on the values of the parameters indicated