TOWARDS the end of “Toy Story 3”, with Andy having left for college, his
much-loved toys from childhood mistakenly face destruction in the maw
of a moving-grate garbage incinerator. If, in real life, the plant had
been built prior to 1989, the plastic toys would have produced a nasty
dose of dioxins and furans—toxic emissions from combustion taking place
in the presence of chlorine—as well as heavy metals and dubious organic
compounds. Until then, few people were aware that such chemicals
presented a serious health hazard, capable of upsetting the immune
system, damaging the liver and causing cancer. Unwittingly, municipal
incinerators were among the worst offenders.
Industry subsequently spent billions retrofitting incinerators with activated-carbon injectors and particle traps to capture the dioxins and furans, as well as volatile metals like cadmium and mercury. Thanks to new regulations, the emission of such toxic chemicals from waste processing has been reduced a thousandfold. Today, the total emission of dioxins and furans produced by all the incinerators in America is less than ten grams a year, according to the Environmental Protection Agency (EPA). By contrast, homeowners burning rubbish in their backyards are reckoned to contribute up to 500 grams a year. Some of the worst emitters are the fireworks used to celebrate the Fourth of July.
Even so, municipal incinerators—especially the new waste-to-energy (WTE) plants that use rubbish as a fuel for generating electricity and heat for local distribution—continue to have an image problem. In America, most communities prefer their waste to be composted—provided, of course, the landfills are nowhere near their own backyards. Yet, without costly plumbing, landfills produce copious quantities of methane from their decomposing waste. As a greenhouse gas, methane does more than 20 times the damage to the environment as comparable emissions of carbon dioxide.
Read more: http://www.economist.com/blogs/babbage/2012/04/garbology-0
Industry subsequently spent billions retrofitting incinerators with activated-carbon injectors and particle traps to capture the dioxins and furans, as well as volatile metals like cadmium and mercury. Thanks to new regulations, the emission of such toxic chemicals from waste processing has been reduced a thousandfold. Today, the total emission of dioxins and furans produced by all the incinerators in America is less than ten grams a year, according to the Environmental Protection Agency (EPA). By contrast, homeowners burning rubbish in their backyards are reckoned to contribute up to 500 grams a year. Some of the worst emitters are the fireworks used to celebrate the Fourth of July.
Even so, municipal incinerators—especially the new waste-to-energy (WTE) plants that use rubbish as a fuel for generating electricity and heat for local distribution—continue to have an image problem. In America, most communities prefer their waste to be composted—provided, of course, the landfills are nowhere near their own backyards. Yet, without costly plumbing, landfills produce copious quantities of methane from their decomposing waste. As a greenhouse gas, methane does more than 20 times the damage to the environment as comparable emissions of carbon dioxide.
Read more: http://www.economist.com/blogs/babbage/2012/04/garbology-0
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