Air Products Converts Wastewater Gas to Hydrogen Fuel
August 20, 2011
Air Products began pumping hydrogen generated from a California municipal wastewater treatment plant into fuel cell vehicles this month. In addition to generating hydrogen, the project also creates electricity and heat for the Orange County Sanitation District (OCSD) in Fountain Valley, CA.
Methane gas from the facility's wastewater treatment holding tanks enters a purification system and then feeds into a fuel cell where it is reformed to hydrogen. This fuel cell produces electricity for use at the OCSD facility. Hydrogen not used by the fuel cell in creating electricity to operate the facility is further purified to vehicle grade for automobile fuel cells. According to Air Products, the process will produce enough hydrogen to fuel 25 to 50 electric vehicles per day, plus generate 250 kilowatts of electricity for the plant.
Hydrogen from renewable sources is required to be in the mix in fueling stations in California. The project received partial funding from the United States Department of Energy and involved the OCSD, Air Products, FuelCell Energy (a fuel cell manufacturer), the National Fuel Cell Research Center at the University of California, Irvine, the California Air Resources Board and the South Coast Air Quality Management District.
Air quality is a major issue in this Southern California region, and emissions are heavily regulated. The project seeks do demonstrate how power, heat and a transportation fuel with no emissions can be generated from a renewable source. Other feedstock sources such as agricultural, food, and brewery wastes and landfill gas can also use this technology.
Air Products is a global supplier of hydrogen and has been a leader in developing hydrogen fueling stations with more than 50 patents in hydrogen dispensing technology. Air Products has long served the huge industrial market for hydrogen, where it is used in refining crude oil, in treating metals, and to hydrogenate oils and fats in the food industry. Other important uses are found in the chemical and pharmaceutical industries and in the manufacture of semiconductors.
While many see hydrogen as the fuel of the future, it cannot compete economically today with the major hydrocarbon fuels such as oil, natural gas and coal. According to the National Energy Education Development Project (www.need.org), hydrogen from electrolysis is ten times more costly than natural gas and three times more costly than gasoline per Btu.
In a two-page white paper on hydrogen (download the PDF here), NEED explains that industry produces most of its hydrogen in a process called steam reforming, where high-temperature steam separates hydrogen from the carbon atoms in methane (CH4). While the NEED paper calls this the most cost effective way to produce hydrogen, it points out the downside is it uses fossil fuels both in the manufacturing process and as the heat source.
Unless, of course, the methane comes from wastewater. Then you've got a whole new equation, which is what Air Products hopes to demonstrate in Fountain Valley.