Water purificn., esp. of sewage - uses only two basic tanks and is used by small family units

摘要

In the continuous automatic cyclic treatment of sewage and waste materials (esp. those contg. >25 ppm. BOD and >25 ppm. total solids) in which the accumulation of sewage in a main tank is time dependent with periods of max. and min. ave. accumulation occurring at regular intervals, (a) in the main tank a biological-chemical oxidn. of accumulated sewage is effected by aeration during periods of max. accumulation. then settling is allowed during the initial portion of min. accumulation; and (b) a pre-reacted floc (I) is introduced into the effluent from the main tank before the end of the biological-chemical oxidn. to produce an instantaneous floc-agglomeration with the effluent kept at optimum pH and with zeta-potential stabilised at -5 to +5 ZP. During the period of min. accumulation, effluent is removed from the tank and more (I) is introduced into it to produce further instantaneous floc-agglomeration. Suspended solids and colloidal particles are then filtered out, and dissolved organic solids are removed by adsorption. Finally (during periods of effluent removal the produced sepd. solids and adsorbed materials are oxidised and removed. Automatic system is esp. designed for use by small family units, and on such a basis it affords high quality effluent H2O suitable (perhaps after chlorination) for use in a variety of domestic or industrial applications (irrigation, washing operations, even as drinking H2O). Costs are very low, and using only 2 basic containers or tanks the system can run for is not 5 years without cleaning.