A gasification pilot project in Sherbrooke, Quebec, which examined gasification as an emerging energy recovery option for diverting municipal solid waste residues from landfill operations, was recently completed. (See "Sherbrooke Evaluates Gasification" in the August/September 2002 edition.)
The project involved two samples of household plastic packaging residues that were gasified: plastic film and a mixed stream of rigid plastic residues. Both samples were subjected to a partial oxidation chemical process able to convert the carbon and hydrogen present into a clean, synthetic gas. Arthur Gordon Environmental Evaluations Ltd. conducted the chemical analysis.
Some of the testing results showed that:
over 93 per cent of the carbon in the plastic residues was converted to synthetic gas (syngas);
90 to 96 per cent of the inherent energy in the feed material was accounted for, with 75 per cent of the energy in the feed converted to syngas;
the levels of lead, mercury and cadmium in the solid residues collected at the cyclones after gasification were all below the level of detection; and,
all of the emissions to atmosphere after the combustion of the syngas were significantly lower than those prescribed by the Province of Ontario’s A-7 Guidelines, which are among the most stringent in the world.
EPIC will provide a more detailed summary of the results on its web site (www.plastics.ca) in late summer 2003