Maintenance Technology published a great story about reframing wastewater from a business of waste disposal into one or resource recovery. Much of the piece focuses on WEF’s recently released Energy Roadmap, which you can read about in this previous Ebulletin story. It also does an in-depth case study of East Bay Municipal Utility District.
Water professionals speak in reverential terms about the wastewater treatment facility run by the East Bay Municipal Utility District (M.U.D.) in Oakland, CA. With regard to sustainability, “These people have already succeeded,” says Barry Liner, Director of the Water Environment Federation’s (WEF) Water Science and Engineering Center. “They had visionaries 20 years ago who started this plant. Now it’s the first recognized wastewater utility in the U.S. to become energy-positive,” a feat it achieved in February 2012. East Bay M.U.D. became energy-positive by adding organic waste to its normal sewage intake and sending the mix to its anaerobic digesters to generate biogas, which it then burns for electricity. The added organic waste includes food-processing and agricultural waste, fats, oils, grease and food scraps, much of which previously went to landfill. The plant’s digesters turn the mixed wastes into nutrient-rich biosolids and biogas, an energy-rich mix of methane and carbon dioxide. A new 4.6 MW turbine helps the plant take advantage of all the gas it produces and create enough extra electricity to sell a portion back to the grid. The process is so successful that the plant is bringing on an additional digester that has nothing to do with wastewater. “It will simply process organic waste and generate more power,” says Liner.
Liner is pleased to note that WEF’s new Energy Roadmap(written to help water treatment plants become more sustainable and using East Bay as an example of the potential) can also help this highly successful operation. “The interesting thing about East Bay is that, because they had all this organic waste, [energy-] generation was the low-hanging fruit for them,” he says. “But they never really looked at energy conservation on the demand side.” He adds that the cutting-edge facility sees the Roadmap as an effective way to help ensure that its daily operation is as energy-efficient as it is energy-positive.