Waste water treating process

Claim 1

A process for treating waste water, comprising of: (a) passing the water into a first chamber where large diameter solid materials settle from the water and are retained in said first chamber, (b) passing water from the first chamber into a second chamber to achieve substantial dilution, said second chamber containing a plurality of gas-water circulators which pump gas from an enclosed surrounding atmosphere into the water and continuously circulate the water in the chamber, with said second chamber being maintained under conditions which favor anaerobic bacterial digestion of waste materials in the water and containing an ash-like sludge, (c) introducing trace amounts of oxygen into the second chamber to favor the growth of a small population of microaerophilic bacteria, (d) passing water from the second chamber into a third chamber containing a plurality of gas-water circulators which pump gas from the surrounding atmosphere into the water and continuously circulate the water in the chamber, with said third chamber being maintained under conditions which favor anaerobic digestion of organic solids in the water and having floating on the surface of the water in said third chamber a plurality of discrete, highly porous media on which bacteria grow, and (e) passing water from the third chamber into a fourth chamber containing a plurality of gas-water circulators which pump gas from the surrounding atmosphere into the water and continuously circulate the water in said chamber, with said fourth chamber being maintained under conditions which favor aerobic digestion of waste materials in the water and having floating on the surface a plurality of discrete, highly porous media on which bacteria grow.