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Brazil: A Recycled City Part 1
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By Mark Taylor A recent programme in the National Geographic series Megacities focused on São Paulo, and some of the surprising efforts underway to not only save the city from all the rubbish it produces, but in recycling, and recycling research. For those who havent had a chance to see this interesting programme heres a summary of some of what goes on around the city.
When you have around 20 million people, depending how you define São Paulo city, in one of the largest cities in the world a never ending problems is going to be rubbish, and where to put it. Everyday the city generates 14,000 tonnes of garbage. For many years this was just placed in open dumps which became magnets for rats, disease and of course people. People who made their living from groping through other peoples garbage.
Bandeirantes Landfill That which motivated the growth of São Paulo, money, is what is now proving a motivation for doing something worthwhile with the rubbish. Bandeirantes is one of the worlds largest landfills, but also a power plant. Prior to being a landfill Bandeirantes was an empty valley, the size of around 175 football fields. Now the valley is filled with layers of trash, around 5 to 8 metres high, sandwiched by layers of soil (currently a total of around 30 million tonnes). The layers of trash produce a nasty and foul smelling byproduct, leachate. To prevent contamination of the underlying soil by the leachate the whole valley is lined with a vast polyethylene blanket, 5 millimetres thick and impenetrable.
Another more useful byproduct of the decomposing rubbish is methane, which is captured by one of 200 vertical tubes placed all over the landfill. By using the methane to fuel the elecricity power plant, it can produce enough electricity to run the homes for 400,000 people. Around half the garbage from São Paulo is dumped in the landfill everyday. Initially the methane from the landfill was burned to the air, to prevent contamination. But the decision was made to prevent this waste of a useful resource and the powerplant was built.
Aside from the money generated by selling the electricity, another arguably more dubious cash earner are selling pollution credits. With the advent of the Kyoto treaty, those who sign up to it and reduce their pollution are able to sell their pollution reduction credits to other countries. Half the money Brazil earns from selling pollution reduction credits is earned from the constructive usage from burning "clean" methane at Bandeirantes.
In the power plant itself the gas is retrieved from the aforementioned tubes scattered around the landfill. The gas from the tubes is chilled and water is removed. The resulting gas is around 50% methane. To comply with the Kyoto protocol the gas volume is of course measured. The gas then flows to one of twenty four generators which converts it to electricity. Garbage in, but not quite so much garbage out.
Bandeirantes can hold about 20 years of rubbish, with the layers left during the first 5 years producing the most methane. One day the landfill will be full though, although there are possibilities to recycle the landfill itself, perhaps as a park.
Part 2 next week...
Previous articles by Mark Taylor:
Brazil: 100 Things To Do in São Paulo Part 3 Brazil: 100 Things To Do in São Paulo Part 2 Brazil: 100 Things To Do in São Paulo Part 1 GPS in Brazil Brazil: PCC Attacks in São Paulo Brazil: Tips on Buying or Renting an Apartment or House Brazil: A Critical Sensitivity Cleanliness is next to Brazilianiness Brazil: Manners Brazil: No Change, No Sale Brazilian TV Brazil: Ubatuba Brazil: Professional Children Brazil: We deliver... everything! Brazil: Terraço Itália Brazil: A Layman's Carnival Guide Brazil: Portunglish or Engluguese? Brazil: Feira Food Brazil: Bilhete Unico flexibility increases Brazil: Finding Work Brazil: U2 Ticket Chaos Brazil: Finding Work Brazil: Termites Brazil: Queues, Queues, Queues Brazil: Let's Go Fly a Kite! Brazil... the Film That Is Brazil: The Bus to Nowhere Brazil: Piracy Brazil: Gestures Brazil: Proclamation of the Republic Brazilian Film Review Brazilian Film Review Brazil: Finados (Day of the Dead) Interjections, exclamations and onomatopoeia in Brazilian Portuguese Brazil: Halloween Brazil says "No" to banning firearms Brazil Humour: Phone Etiquette Brazil's Gun Referendum Brazil: Scams Brazil: Moby Review Brazil: Keeping in touch via the Internet - Part 5 Brazil: Keeping in touch via the Internet - Part 4 Brazil: Avril Lavigne at Pacaembu Moby in Brazil Brazil: Keeping in touch via the Internet - Part 3 Brazil: Keeping in touch via the Internet - Part 2 Brazilian Film Review Brazil: Keeping in touch via the Internet - Part 1 Brazil: First season of Lost repeated on AXN
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6/13/2006
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