A rubbish business model | Economist.com

A rubbish business model | Economist.com:

"Several firms have taken that idea to heart and are seeking profitable ways to turn rubbish into fuel.....

"The idea might sound far-fetched, but there are several ways to convert organic waste into various grades of fuel, at least in the laboratory. You can gasify rubbish by heating it and turning it into synthesis fuel, which is then fed into a reaction called the Fischer-Tropsch process. This technique for converting carbon monoxide and hydrogen into liquid hydrocarbons using a catalyst was invented in Germany in the 1920s and was used by the Nazis to convert coal into fuel during the second world war. An alternative method involves breaking down cellulose using various catalysts to accelerate the decomposition of organic plant residues into ethanol.

"Household rubbish presents special problems, since it is an unpredictable mishmash of all sorts of stuff. Allen Hershkowitz, director of the solid-waste programme at the Natural Resources Defence Council (NRDC), says that no technology can take large amounts of mixed household waste and profitably convert it into ethanol or any other kind of fuel. He also notes that, although the country's landfills seem to be overflowing, America in fact produces only about 230m tonnes of municipal solid waste a year, compared with more than 2 billion tonnes of farm waste. The NRDC reports that much of the solid waste in landfills is made up of recyclables like plastic, or food waste that could be used as compost. Burning such things for fuel may not count as a gain for the environment."