Zimpro/passavant Inc.

Zimpro Environmental, Inc.

Zimpro Passavatn Environmental Sys.

John K Berrigan, Jr

William M Copa

David A Beula

A process is described for aerobically treating wastewater containing volatile compounds to degrade the volatile compounds without liberating them to the atmosphere. Influent wastewater and return sludge from an aerobic biophysical wastewater treatment system are contacted in a preaeration zone where a minimum dissolved oxygen concentration of about 1 mg/l is maintained. In this preaeration zone a significant portion of the volatile compounds are biologically degraded. The minimum oxygen concentration in the preaeration zone is attained by prior aeration of the return sludge or by adding a small amount of oxygen to the preaeration zone. The mixture of influent wastewater and biophysical solids depleted of volatile compounds then flows to an aeration zone for further removal of pollutants.

Preparation treatment of volatile wastewater components

Preaeration treatment of volatile wastewater components

Regenerated adsorbent particles, such as activated carbon, are recovered from a wet oxidation-regenerated mixed liquor sludge from a wastewater treatment system by diluting and settling a blowdown slurry from the wet oxidation reactor to obtain a first aqueous phase containing primarily regenerated adsorbent particles and fine ash particles and a first solids phase containing primarily grit particles. The first aqueous phase is combined with a portion of the regenerated adsorbent particle slurry withdrawn from the upper portion of the wet oxidation reactor and, after treatment with a dispersing agent and then an anionic flocculating agent, the resulting mixture is settled to obtain a second aqueous phase containing primarily fine ash particles and a second solids phase containing primarily regenerated adsorbent particles. The second solids phase is recycled to the treatment system for reuse and, after treatment with a cationic flocculating agent, the second aqueous phase is settled to obtain a substantially particle-free third aqueous phase and a third solids phase containing primarily fine ash particles. Slurries containing the grit and fine ash particles are combined and dewatered prior to disposal.

Growing community of inventors

Wausau, WI, United States of America

John K Berrigan, Jr