SEWAGE TREATMENT PROCESS

2064809 9102698 PCTABS00003 A process for the treatment of sewage or other wastewater containing organic matter which comprises the steps of: (a) mixing sewage or other wastewater containing organic matter with a coagulant/adsorbent which is finely divided particulate mineral or clay material the individual particles of which have a thin hydroxylated surface layer, under conditions whereby at least a substantial proportion of the organic material in the sewage or other wastewater containing organic matter becomes attached to the coagulant/adsorbent; (b) separating the coagulant/adsorbent with attached organic material from the mixture to leave a treated liquid effluent; (c) treating the separated coagulant/adsorbent from step (b) with alkali thereby to release the organic material therefrom, separating the coagulant/adsorbent from the resultant concentrated slurry containing the organic material; and (d) adding acid to the concentrated slurry of organic material to lower the pH to less than 4 and thereby to obtain a sludge which separates under gravity and a supernatant liquid which optionally may be recycled to acidify the incoming sewage or other wastewater containing organic matter.