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

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12. International <strong>best</strong> <strong>practices</strong>
12.1. The SUMTER plant in South Carolina, USA
In the city of Sumter two are existent problems in waste management. These
are sewage sludge <strong>and</strong> waste wood, mainly tree bark from industry operating in
the region.
Picture 71.: Sumpter drying plant
The problem was solved by producing energy from the woodchips in order for
the sewage sludge to be dried. The sludge is used in agriculture as a fertilizer.
The plants specification are:
storage area for wood <strong>and</strong> bark waste
shredding equipment for waste wood
front loader <strong>and</strong> weighing device
buffer silo for wood/bark
combined grate firing with lean gas combustion (1000°C hot gas) with
automatic ash discharge
directly fired st<strong>and</strong>ard drum drying plant for evaporation of 4 t
liquid/hour, approx. 5,500 tones d.s. annually, with sewage sludge predewatered
to 15% d.s. (digested). Alternatively, the drying plant can be
operated partially or entirely with primary energy.
At the following figure the process that takes place in the plant can be seen
(Figure 57.):