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

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used for the construction of l<strong>and</strong>fill sites. The combustible fractions separated
out are added to the SRF.The separation of electronic scrap, iron <strong>and</strong> nonferrous
metals using magnetic <strong>and</strong> eddy current separators produces a
marketable product, the income from which helps to reduce the overall
treatment costs.
The SRF is passed over four pelleting presses (Figure 4.19) to form around 20
mm sized pellets for reuse in the Methanol Plant. The pellets are mixed with a
small quantity of coal <strong>and</strong> are then supplied to gasification reactors. There the
organic components of the input materials react with a mixture of steam <strong>and</strong>
oxygen at a pressure of 25 bar <strong>and</strong> temperatures well above 1000 °C to form
synthesis gas. (Wastesum project Del 3A,. 2010)
The synthesis gas produced primarily consists of carbon monoxide, carbon
dioxide <strong>and</strong> hydrogen. Following thorough cleaning, the synthesis gas passes
into a plant that produces methanol. At a pressure of 45 bars, a temperature of
500 °C <strong>and</strong> in the presence of a catalyst, the gas constituents react to form
methanol. Annually, approx. 16,600 t methanol are produced in the SVZ using
the 42,500 t of pelleted SRF produced in the Dresden Waste Recycling Plant
<strong>and</strong> 15% coal. This equates to 21.5 million liters. This can then replace around
16.5 million liters of petrol.
Picture 31.: Pelleting machine of the Dresden plant in Germany
(Wastesum project Del 3A., 2010)
The Dresden plant has been equipped with the thermal-regenerative waste air
treatment technique. A prerequisite for the efficient use of this cleaning