Electrical Power Generation From Biogas Upgrading

Abstract

Great interest has been expressed in the harnessing of methane biogas from the decomposition of biowaste to combust in an electric generator to produce electricity. Biogas produced in this way is a mixture of methane gas, carbon dioxide, and hydrogen sulfide. To use this gas as a fuel for an electric generator, the gas mixture needs to be purified and dried to create a purer methane fuel in a process called upgrading. The application of such a technology has been posed as most effective in a situation where biowaste in the form of excrement, whether human or animal, is plentiful, and where conventional reliance on electric infrastructure is difficult. The Washington State Department of Transportation (WSDOT) has proposed one such application lies in the 47 safety rest areas possessed by the state. The goal of this project is to design and prototype a system which will take biowaste, in this case cow manure, and create a self-contained system which will collect and filter biogas to create methane fuel and supply this fuel to a generator modified to run on methane to produce electricity. This project successfully produced 8.5 pounds-per-square-inch of mixed biogas in an anaerobic digester and has created a filtration system to upgrade the gas for fuel in the electric generator. The mixed biogas is at a methane concentration of 100% of the lower-explosive-limit.