Ch2m Hill, Inc.

Ch2m Hill Canada Limited

Gore & Storrie Limited

George V Crawford

Glen T Daigger

Bruce R Johnson

Paul F DaSilva

This disclosure describes wastewater treatment systems and methods of treating wastewater. In one exemplary method, a wastewater is split into first and second wastewater fractions. The first fraction is delivered to a membrane bioreactor, which may produce an effluent with a low pollutant concentration, and the second fraction is delivered to a biological wastewater treatment system, which may yield a higher pollution concentration yet have a shorter solids retention time. Some implementations of the invention can routinely meet or even exceed pollution discharge standards quite economically during normal operation, yet retain significant flexibility for handling seasonal or sudden variations in the flow rate of wastewater into the system. In select adaptations, waste activated sludge containing heterotrophs, autotrophs, and (optionally) polyphosphate accumulating organisms is delivered from the membrane bioreactor to the biological wastewater treatment system.

Wastewater treatment system

Method of treating wastewater

An anaerobic reactor for treatment of waste water comprises a primary reactor or zone of the suspended growth type and a secondary reactor or zone of the fixed filter bed type disposed directly above and in liquid contact with the primary reactor. Liquid to be treated is fed continuously into the primary reactor and moves upwardly through the primary reactor, then through the filter bed and out via an outlet above the filter bed. Gas generated in the primary reactor moves upwardly through the liquids and through the filter bed, to cause vertical mixing throughout the zones and to keep the filter bed from clogging.

Hybrid high rate anaerobic treatment apparatus

Hybrid high rate anaerobic treatment process

Growing community of inventors

Toronto, Canada

George V Crawford