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New tech makes renewable natural gas from sewage sludge
A pilot study of a new method for treating sewage sludge from a wastewater treatment plant efficiently created renewable natural gas while reducing the cost of the treatment. The work in the Chemical Engineering Journal could help communities sustainably clean up waste while getting renewable natural gas for their energy needs. When the researchers pretreated sludge collected from a nearby wastewater facility, they produced 200% more renewable natural gas compared to current practices and reduced the final disposal cost by nearly 50%. Renewable natural gas could be used in the same way as fossil-fuel based natural gas for a wide variety of uses, including for electricity generation, home heating, or for transportation without the same climate effect as fossil fuels. “This technology basically converts up to 80% of the sewage sludge into something valuable,” says Birgitte Ahring, corresponding author on the paper and a professor in Washington State University’s Bioproducts, Sciences, and Engineering Laboratory and the Gene and Linda Voiland School of Chemical Engineering and Bioengineering. “If we can replicate this work on other organic materials, we’ll have a waste treatment technology that is world-class when it comes to efficiency.” Wastewater treatment facilities use large amounts of electricity to clean...