美國加州東灣水利局(East Bay Municipal Utility District, EBMUD)首創利用廚餘生產再生能源。
水利局把從舊金山和康特拉科斯塔(Contra Costa)縣的餐館和商業食品加工厰收集來的廚餘加以利用，生產綠色再生能源，並用的技術製作堆肥。
舊金山市長紐森（Newsom）於6月23日簽署了美國首項強制性堆肥法令。他表示：「這是該國最完整的回收和堆肥法令，同時也是首度全面要求一般民衆和企業將丟棄的食物作為堆肥的材料。」
如今以後，一般民衆和企業得辛苦點多做些堆肥，並且想辦法避免將廚餘送往掩埋場。
東灣水利局的厭氧沼氣池自2004年開始，即以帶頭的姿態運作至今。目前每週處理餐館和食品加工設施的廚餘量為90噸。
厭氧醱酵，顧名思義就是不用氧氣，而是借助沼氣池內的細菌來分解食物。細菌將食物中的有機碳轉換成含有二氧化碳和甲烷的沼氣。
整個過程先從把要運走作囘收處理用的廚餘分類開始。廚餘被載到水利局的主要污水處理廠之後，在一只大箱子裏分解 -- 沼氣池。
當廚餘分解時，沼氣池將其釋放出的甲烷聚集起來並轉換為能量，供污水處理設備發電使用。經過沼氣池處理過後剩餘的殘渣，可以用來做堆肥以及種植糧食作物使用的天然肥料。
廚餘是美國第二大類的都市固體廢物，佔了垃圾量的18%。
美國環保署表示，如果採用厭氧醱酵方式來處理美國國内一半以上廚餘的話，產生的電力足以供約250萬用戶一年所需。
環保署還表示，掩埋場是美國的第二大非天然（人爲因素）甲烷來源。而廚餘既是造成掩埋場釋出甲烷的主要成因。
加州一共有137個污水處理廠配有處理污泥的厭氧醱酵池。目前估計仍有15%-30%未使用的產能。環保署官員建議，過剩的產能恰巧提供了加州一個有效回收利用廚餘的機會。
The East Bay Municipal Utility District is pioneering a method of generating renewable energy using food scraps.
The utility takes food waste from San Francisco and Contra Costa County restaurants and commercial food processors and uses the waste to produce green renewable energy and compost through anaerobic digestion.
On June 23, San Francisco Mayor Gavin Newsom signed the nation's first mandatory composting law. "It's the most comprehensive recycling and composting legislation in the country and the first to require residents and businesses to compost food scraps," Newsom said.
Now, residents and businesses must begin increasing their composting efforts and finding new ways to keep food scraps out of the landfill.
EBMUD's anaerobic digester, in operation since 2004, is leading the way, and currently processes 90 tons per week of post-consumer food waste from restaurants and food processing facilities.
Anaerobic digestion, which means without oxygen, works by using bacteria inside the digester to decompose the food. It converts organic carbon in the food into biogas, which contains both carbon dioxide and methane.
The process begins when food waste is separated for disposal and pick up. At the EBMUD's main wastewater treatment plant, the food waste is broken down in large containers - the anaerobic digesters.
As the food decomposes, the digester captures the methane to power the wastewater treatment plant. Material remaining after the digestion process can be composted and used as a natural fertilizer to help grow food.
Food waste is the second largest category of municipal solid waste in the United States, accounting for 18 percent of the waste stream.
If half of the food waste produced in the United States was anaerobically digested, the U.S. EPA says, enough electricity would be generated to power about 2.5 million homes for a year.
Landfills are the second largest source of human-caused methane in the United States, and food waste contributes significantly to landfill methane production, the EPA says.
In California, there are 137 wastewater treatment plants that have anaerobic digesters for sludge, with an estimated excess capacity of 15-30 percent. This excess capacity could provide a potent recycling opportunity for post-consumer food waste in California, EPA officials suggest.
作者
In my healing journey and learning to attain the breath awareness, I become aware of the reality that all the creatures of the world are breathing the same breath. Take action, here and now. From my physical being to the every corner of this out of balance's planet.
