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

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filtration or electrostatic precipitators, before the cleaned gases are discharged
to the atmosphere.
Figure 14.: Combustion processes for mass burn incineration. (Thermal methods of
municipal waste treatment., 2009)
Mass burn incinerators are specifically designed to cope with all components in
the MSW stream, which generally has a relatively low average gross calorific
value (GCV), in the range 911 GJ/tone – about one third that of coal or plastics.
However, individual types of waste vary markedly in their calorific values, from
zero for wet putrescible wastes to over 30 GJ/ton for some plastics. Loading an
even mixture of wastes into the combustion chamber is therefore very
important to ensure that the overall heat input stays in 9-11 GJ/ton range for
which the plant is designed to operate. Wastes are therefore mixed in the
loading pit to even out obvious differences in composition before loading the
combustion chamber.
Excess amounts of high CV waste like plastics can lead to high temperature
corrosion of heat exchange surfaces due to the high concentrations of chloride
found in MSW. The need to avoid high temperature corrosion by limiting
combustion chamber temperatures is one of the main reasons why the thermal
efficiency of waste incinerators is low, compared with coal-burning steam cycle
power stations. On the other h<strong>and</strong>, if the GCV of incoming waste falls much
below about 7 GJ/tone, then the waste may not burn properly (or even at all)
under the conditions inside the combustion chamber, <strong>and</strong> efficiency of energy
recovery would markedly decrease. A pilot fuel would therefore be required to
sustain efficient combustion <strong>and</strong> to ensure that statutory temperature