Manure treatment according to the Trevi-concept

In Flanders great amounts of livestock, especially pigs, lead to a surplus of manure that can not be spread on farmland because of the prevailing fertilizing restrictions. Aside that, Flemish government obliges farmers with a surplus of 7500 kg total P2O5 production to treat this excess of manure partially or totally. Trevi N.V. developed a manure treating system that starts with the separation of the raw manure in a solid fraction and a liquid fraction. The solid fraction can be exported after drying and hygienisation in the condensation drier, which is characterised by the absence of off-gases. The liquid fraction is treated in a biological plant and contains only 10 to 15% of the original amount of nutrients. As a result of this, the biological effluent can be spread on farmland at a bigger quantity (100-150 ton/ha) in comparison with raw manure. This biological effluent needs further polishing to obtain an effluent that can be discharged into surface waters. This was realised in coordination with Danis N. V. at the Discover plant in Izegem. In this plant, an evaporator treats the biological effluent and produces a dischargable condensate.