Evaporation plant treating effluent from hide and skin preservation process, operates two stage heating process, to flocculate and filter out contaminants, recovering salt for recycle to process
The effluent is first heated to 70 deg C, organic material being flocculated and filtered out together with other contaminants. As a function of the degree of contamination, the first stage may be carried out repeatedly. In a second stage, the filtered brine is then heated to 95 deg C and re-filtered. Salt recovered is returned to the process. The second stage is repeated until the water from the brine has been evaporated and led off as effluent vapor (11). Process stages run continuously. An Independent claim is included for the plant carrying out the process, summarized as a collection tank (1), evaporator (2), filter (3) and stock vessel (4), together with suitable supply and recycling lines. Preferred features: A pump (14) is mounted in the collection tank, another (15) in the supply line (8), with a valve (19). The filter includes a pump (18). In the recycle line (10) there is a pump (16) and three-way valve. Further plant equipment is elaborated.