| abstract |
Process and installation for the treatment of liquid waste containing water and dilute organic pollutants, such as pig manure, or effluents from agro-food industries, characterized in that it comprises at least: e) a step of thermal evaporation 1 of a substantial proportion of said water, and f) a step 2 of incineration of the concentrate 9 obtained in the previous step. Preferably an evaporator 1 of the mechanical vapor re-compression type is used, combined with an incinerator 2 of the fluidized bed type and re-circulation (4) of heat-transfer material, in particular of sand, and pre-mix (5) of this heat-transfer material with at least a substantial part of the concentrate (9) obtained in the evaporation step. This process actually destroys the slurry, in particular the nitrates, by a very inexpensive process, making it possible to recover its useful elements, including water with COD <50, and the phosphates in the form of dry powder reusable in fertilizer, and which does not produces either useful or non-polluting agents. |