The aim of the research project, which comes from the University of Waterloo, is to devise technology that can generate renewable natural gas from manure. This gas could then be added to current energy supplies to allow for the heating homes and to provide power to manufacturing sites.
The study is not simply focused on generating additional energy, the second aim is to reduce levels of harmful gases, which are released into the atmosphere by naturally decomposing manure. The harmful gas levels are highest when manure is spread across farm fields as fertilizer. Moreover, the use of gas produced from manure would mean lower demand for gas produced from fossil fuels, and thus a reduction in the use of fuels that contribute to global warming.
To explore the feasibility of using manure, the scientists constructed a computer model that replicated a 2,000-head dairy farm in Ontario, which collects manure and converts it into biogas using anaerobic digesters. This showed that turning biogas from manure into renewable natural gas, required mixing the biogas with hydrogen and then processing this through a catalytic converter. A chemical reaction in the converter (methanation) leads to the production of methane from carbon dioxide in the biogas.
The computer model showed that a $5-million investment in a methanation system at the farm would give a five-year payback period. The researchers hope to gain Canadian government interest in the scheme and to establish a viable working plant.
The research has been published in the journal International Journal of Energy Research. The research paper is titled “Upgrading biogas produced at dairy farms into renewable natural gas by methanation.”
