WASTEWATER TREATMENT PROCESS THAT UTILIZES GRANULAR SLUDGE TO REDUCE COD CONCENTRATION IN WASTEWATER

摘要

A wastewater treatment process that employs anaerobic granular sludge or biomass to remove chemical oxygen demand (COD) from the wastewater. Certain constituents, such as COD, nitrogen, calcium, other dissolved solids, suspended solids, can impair the effectiveness of the granular biomass. Thus, the process employs treatment units to remove these inhibiting constituents to produce a treated effluent or stream. At least a portion of the treated effluent is recycled and mixed with the influent wastewater to reduce the concentration of these inhibiting constituents.

主权项

1. A method of employing granular sludge to remove chemical oxygen demand (COD) from influent wastewater and removing constituents from the wastewater that impair the formation and effectiveness of granular sludge in reducing the concentration of COD in the wastewater, the method comprising:
directing the influent wastewater into a first reactor having the granular sludge and operating the reactor under anaerobic conditions and contacting the influent wastewater with the granular sludge to remove COD from the influent wastewater; directing the influent wastewater from the first reactor to a downstream treatment unit; in the downstream treatment unit, reducing the concentration of one or more of the inhibiting constituents and producing a treated effluent; and substantially reducing the concentration of the inhibiting constituents in the influent wastewater by diluting the influent wastewater with at least part of the treated effluent of the downstream treatment unit.