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

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pulled through an induced draft blower, which maintains all equipment under
a negative pressure. (Moustakas et. al.,2003)
Once gasification is completed, the inorganic portion of waste melts by contact
with a pool of molten slag. The layer of molten slag is maintained in the liquid
state by a current flowing through two graphite electrodes. Electrodes are
positioned slightly above the surface of the bath, creating two electric arcs. The
current also flows through the molten bath. Thus, both resistive <strong>and</strong> arc mode
heating are used. Below the surface of the slag, a layer of molten iron (or iron
heel) is maintained, improving the flow of the current through the slag. (Table
4.) shows the typical application range of the main different thermal
technologies. (Moustakas et. al.,2003)
Technology
Typical application range
(tones/day)
Moving grate 120-720
Fluidised bed 36-200
Rotary kiln 10-350
Modular (starved air) 1-75
Pyrolysis 10-100
Gasification 250-500
(Table 4.): Typical throughput ranges of thermal technologies
3.3. L<strong>and</strong>filling
3.3.1. Introduction
Historically l<strong>and</strong>filling has been the major practice for municipal solid waste
disposal. Nowadays municipalities are forced to find new methods for waste
disposal due to critical environmental problems from old l<strong>and</strong>fills <strong>and</strong> a lack of
l<strong>and</strong> availability caused by a fast growing population <strong>and</strong> a higher rate of waste
production. L<strong>and</strong>filling solid waste is a permanent disposal process by which
we spread, compact, <strong>and</strong> cover (seal) waste with either ash from the Waste-to
Energy facility or soil. It is still the most common form of disposal in the vast