Two heads are better than one, particularly when the heads hold knowledge of two distinct technologies being combined into a single system. That was the case when an environmental engineer from the consulting firm ESS collaborated with the operations manager of a Texas dairy that was expanding into cottage cheese production and needed a treatment system for a high-strength wastewater stream. The plant already was generating more than 10,000 gallons a day of wastewater, and the additional production would chip in another 25,000 gallons, with a chemical oxygen demand (COD) of more than 60,000 milligrams per liter (mg/L).
Aerobic digesters were rejected as too large and impractical for the site, and the men concluded available technology would not meet their requirements. The solution was to combine the dairy’s expertise in ultra-filtration with the consultant’s knowledge of anaerobic digesters.
Vince Taylor, now president of Daisy Brand Inc., Dallas, and John Ewing, now with Biothane LLC, call their system an anaerobic membrane bioreactor, or AnMBR. A beta version began operating at Daisy’s Garland, TX facility in 2007. A larger system now treats 50,000 gallons a day and discharges effluent with COD of less than 300 mg/L. Commercial development of AnMBR for a variety of applications is being guided by Biothane’s Graig Rosenberger, manager of the renewable energy group.