Patent ID: 7416668

Claim:
A chemical/biological wastewater treatment plant method for wastewater with dissolved and undissolved solids comprising: a. testing water quality at various points in a wastewater treatment plant for its contaminant and solids composition, b. determining the end use effluent requirements for the treatment plant's treated wastewater, c. selecting a treatment point in the wastewater treatment plant for pH adjusting and injecting sulfur dioxide into the wastewater to meet the end use effluent and solids requirements, d. deodorizing and conditioning the wastewater at the selected point by injecting into the wastewater sulfur dioxide at a pH which generates sufficient SO2 to condition solids for separation and deodorize the wastewater, e. holding the sulfurous acid treated wastewater in a detention vessel, which captures any excess SO2 emitted by the wastewater for reinjection, until the suspended solids agglomerate, dissolved solids and ammonia are conditioned, and the required effluent disinfection occurs, f. screening the agglomerated solids from the sulfurous acid treated wastewater for disposal to reduce the suspended solids in the separated treated wastewater having elevated BOD dissolved and suspended solids and ammonia nutrients to a concentration level required by the end use effluent requirements for discharge, g. pH adjusting the separated nutrient wastewater solution and any suspended solids to reduce the biocidal properties of any free SO2 in the wastewater and provide the pH required for subsequent environmental biological treatment, and h. environmentally biologically treating the separated nutrient liquid solution and any suspended solids by land applying it for plant consumption, and/or passing it through aqueous plant or microbial reduction of the dissolved solids and ammonia for BOD compliance to produce water of sufficient quality to meet open stream and ocean effluent discharge requirements.