Oxygenation system lowers oxygen demand for Koch Foods’ wastewater treatment facility
A custom oxygen booster system from Linde LLC, known as the SOLVOX oxygenation system, proved effective in dramatically lowering biochemical oxygen demand (BOD) for an on-site wastewater treatment facility for Koch Foods’ poultry deboning plant in Morristown, Tenn.
The SOLVOX system was designed and retrofitted for an existing 225,000-gallon aerobic equalization tank feeding a dissolved air flotation (DAF) units, which are widely used to separate 95-99% of fats, oils and greases and total suspended solids in organic wastewater treatment plants. Yet, they are less effective in lowering BOD, which is sometimes necessary to reduce odors and meet municipal discharge requirements.
Key to success of the new system was control of soluble BOD (sBODs).The poultry processing plant produces more than 70 million pounds of cut wings and boneless chicken nuggets, tenders and breasts every year. While aeration systems may follow DAF pre-treatment and are almost always part of publicly operated wastewater treatment facilities, Larry Moore, professional engineer and professor of environmental engineering at the University of Memphis and consultant for the Tennessee Manufacturing Extension Program (TMEP), recommended oxygenating the wastewater before the DAF unit. Moore analyzed the wastewater treatment complex on behalf of the City of Morristown and TMEP and reviewed BOD treatment options. TMEP does not endorse or warranty any specific method, product, process or service. It is an industrial assistance program designed to help industries make sound decisions regarding environmental management.
“Oxygenation before DAF may be counterintuitive since water can only hold so much oxygen. But, Koch Foods’ wastewater was well below oxygen saturation concentrations because of the level of soluble BOD that remained after screening solids. The presence of the equalization tank before the DAF unit made O2 pre-treatment possible and cost effective,” he says.
Barry Calfee, certified environmental and safety compliance officer at Koch Foods, Park Ridge, Ill., contacted Linde, Murray Hill, N.J. The Linde team estimated that costs for the proposed SOLVOX system would be about as low as an acid treatment system, yet would also offer significant environmental advantages.