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"As much as we love them, our pets leave a lot of manure behind them in yards and on the street and that can be a major source of contamination of groundwater."
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San Francisco, a leader in urban recycling, is preparing to enlist itscaninepopulation for a first in the United States: converting dogpoopinto energy.
Norcal Waste Systems Inc., the city's largest garbage company, plans to test collection carts and biodegradable bags in a city-center park popular with dog walkers.
A city study found that almost 4 percent of all the garbage picked up at San Francisco homes was from animal waste destined for the city's landfill, Norcal Waste spokesman Robert Reid said. San Francisco has anestimated120,000 dogs.
"The city asked us to start thinking about apilotprogram to recycle the dog poop in order to cut back adding more waste in landfills," Reid said.
Dogfecescould be scooped into a methane digester, a device that uses bugs and microorganisms to gobble up the material and emit methane, which would be trapped and burned to power a turbine to make electricity or to heat homes.
Dogs and cats in the United States produce about 10 million tonnes of waste a year, Will Brinton, an environmental scientist and owner-director of Woods End Laboratories in Maine, said.
"As much as we love them, our pets leave a lot of manure behind them in yards and on the street and that can be a major source ofcontaminationof groundwater," Brinton said.
European cities such as Zurich, Frankfurt, Munich and Vienna are operating biomass programs to turn waste into gas, he said.
San Francisco runs an aggressive program to recycle bottles, cans, paper and other trash and now diverts two-thirds of its garbage away from landfills.
The city's goal is a 75 percent diversion by 2010 and zero new waste in landfills by 2020.
(Agencies)
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旧金山在城市垃圾的回收利用方面一直走在世界前列，最近又打算在其市内的"狗公民"身上大做环保文章。这是美国国内第一次尝试将狗粪转化为能源。
旧金山最大的垃圾处理公司，诺考尔废物系统有限公司计划在市中心一个遛狗人经常光顾的公园里试点使用垃圾车和可降解塑料袋。
该公司的发言人罗伯特·里德说，据一份旧金山的城市调查显示，在抽样的所有家庭中，几乎4%的垃圾都来自动物排泄物。而这些动物排泄物会被送往该市的垃圾掩埋场处理掉。在整个旧金山，大约有12万只狗。
罗伯特说："为了不再给垃圾掩埋场增添更多的负担，市里要求我们开始考虑这个试点项目，即，回收利用狗的排泄物。"
狗粪将被倒入一个沼气消化池的装置，然后被虫子和微生物分解并释放出沼气。而这些沼气被收集起来，燃烧之后可以带动涡轮发电或者给室内供暖。
缅因州伍兹恩德实验室的所有者及主管、环境科学家威尔·布林顿说，在美国，猫和狗每年产生的排泄物可达约1000万吨。
布林顿说道："我们有多爱我们的宠物，它们就在院子和大街上留下多少'肥料'。然而这些肥料将成为地下水的主要污染源。"
他还提到，像苏黎士、法兰克福、慕尼黑和维也纳这些欧洲城市也都正在开展将排泄物转化为天然气这样的生物项目。
旧金山对废旧瓶子、罐子、纸张和其它垃圾的回收再利用实行了大胆的计划。如今，该市三分之二的垃圾都不用再送到垃圾掩埋场处理了。
旧金山的目标是，到2010年，该城市的垃圾转化率达到75％，而到2010年，没有垃圾会再被送到垃圾掩埋场。
(中国日报网站编译)
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Updated: 2006-02-28 08:37
