(best examples and good practices) on household organic waste ...

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Gasification (Figure.19) using oxygen (which is more expensive due to
cost/hazard of oxygen generation) produces a medium heating value (MHV)
gas which can either be used as a synthesis gas (e.g. for conversion to
methanol) or for limited pipeline distribution. Steam (or pyrolytic) gasification
produces a MHV gas.
A variety of gasification reactors (running at either atmospheric pressure or
pressurized) have been developed, including fluidized (Figure 2.21) <strong>and</strong> fixed
bed. There are numerous advantages/disadvantages to each configuration.
Incomplete oxidation due to reactor design <strong>and</strong> feedstock anomalies can
contaminate the product gas, <strong>and</strong> where air is used, this will result in higher
than expected NOx emissions. Circulating fluidized bed gasifies are seen as
more versatile since char can be recycled.
Figure 19.: TPS circulating fluidized bed gasification plant <strong>and</strong> gas cleaning
plant
(Thermal methods of municipal waste treatment.,2009)
The fuel gas can be used in thermal combustion engines to produce energy; in a
steam turbine or a boiler; or as a raw material resource to produce methanol,
hydrogen or methyl acid. Syngas includes carbon dioxide, methane, carbon
monoxide, hydrogen, nitrogen <strong>and</strong> ammonia. Small quantities of hydrochloric
acid, hydrofluoric acid, hydrobaric acid, sulphur dioxide <strong>and</strong> nitrogen oxides