Substitution of fossil energies in water management, DE

Using Shredder Fibres for sludge de-watering

In order to centralize the sewage sludge treatment in the catchment of the river Emscher the Emschergenossenschaft runs a sludge pipeline system for 3 large waste water treatment plants (WWTP), the WWTP Emscher mouth with 2,400,000 PE, the WWTP Alte Emscher Duisburg with 500,000 PE and the WWTP Bottrop with 1,340,000 PE. The sludge conditioning process, the sludge de-watering in chamber filter presses and the incineration in fluidised bed furnaces takes place on the WWTP in Bottrop.

Before incinerating a conditioning and de-watering of the sludge is necessary. Fine black coals are mixed with sludge to support the de-watering process and to provide a higher calorific value.

Now the idea is to substitute coal with a product from car recycling, the so called shredder fibres, a material with a good de-watering result. The effect is a reduction of fossil fuels. The substitution of coal to recycled material reduces the green house gas emissions which contributes to climate change mitigation measures.

A testing phase has been conducted in 2008 to make sure that no dangerous matters end up in the final effluent of the WWTP or in the emissions of the incineration. The testing phase is attended by a large monitoring programme including an extensive analysing programme which will be scientifically reviewed by March 2009. A positive evaluation assumed, the preparation and modifications for regular operation will be started in 2009.