Patent ID: 7297274

Claim:
A fixed-film anaerobic system for treating flushed waste comprising: a) a digester having a floor and an upper and a lower region; b) more than one layer of non-pliant media supported within the digester, wherein said layers consist of at least one layer of media of substantially vertically-oriented channels having a first diameter and a first cross-section, and at least another layer of media of substantially vertically-oriented channels having a second diameter and a second cross-section, wherein the second diameter is different from that of the first diameter, wherein at least one layer of the media consists of non-corrugated channels and at least another layer of the media consists of corrugated channels, and wherein said media immobilizes anaerobic microorganisms; c) an influent line to direct the flushed waste into the digester; and d) an effluent line to remove treated flushed waste from the digester.