Treating water used for cleaning food smoking equipment - by reducing pH of water by acid, mixing with bentonite, sedimenting and passing over carbon filter bed

摘要

In treating waste water from smoked food prodn. units, acid is added to the water to bring its pH value to 1 to 2, it is then mixed with silicate flour and undergoes a sedimentation process, from which the remaining liq. is taken to a C filter. Sodium bisulphate is the pref. acid, and the silicate flour is pref. in the form of bentonite. Granular lignite coke is used in the carbon filter, and the water remains in contact with it for 0.5-1.0 hrs.. The filter is regenerated by repeated flushing with clean water. The treated water may be recirculated for further use in cleaning the smoking equipment and chambers, as may be the water used for regenerating the carbon filters. USE/ADVANTAGE - This invention applies to the treatment of water which has been used for cleaning equipment used for producing smoked fish etc., and which is therefore very alkaline and is contaminated with smoke and with food particles. The chemical oxygen deficiency of the waste water is reduced to an acceptable level using an economical procedure.