FOERFARANDE OCH ANORDNING FOER SKYDDANDE AV EN BIOREAKTORS UNDER TRYCK VARANDE TRYCKBEHAOLLARE MOT YTTERST STORA SVALLNINGAR AV INSTROEMMANDE AVFALLSVATTEN

摘要

A method and apparatus is provided whereby a pressurized long vertical shaft bioreactor is protected against extreme surges of influent waste liquid. The method provides for the transfer of excess waste from the top of the bioreactor head tank to an adjacent collection vessel where, in response to the pressure created in the bioreactor, the collected waste is caused to overflow and is returned to the influent waste stream. The method permits the return of waste from the reactor to the influent stream while bypassing the normal circulation route through the reactor. Simplification of control is provided and float or level control valves may be eliminated thereby reducing construction, operating and maintenance costs.