By Karen Mancl
In 2000, a small, family owned meat processor was facing closure. They were under orders from Ohio EPA to change the way they handled their wastewater. Abandoning the smelly lagoon system they were permitted to use for years to connect to the city treatment plant was too expensive.
Through industry, university and government cooperation, a new way to treat their wastewater was developed and it saved the company. The Ohio EPA agreed to allow the company to work with Ohio State University to study using sand bioreactors to treat the high-strength, high-fat content wastewater. After a 2-year lab study in the Department of Food, Agricultural and Biological Engineering at OSU using the meat processing wastewater, the simple technology was tested in a small pilot plant built by the meat processor.
The pilot plant success led to obtaining a permit to construct a full-scale sand bioreactor treatment plant in 2010. The meat processor was able to build the 200,000-gallon per day plant themselves on 4 acres that went into operation in August 2012.
The reaction of the neighbors was surprising. The residents in the subdivision of homes across the road from the treatment plant were understandably concerned about odors. In November 2012, the company owner visited nearby homes to thank the neighbors for their patience and offered them a turkey in apology for the construction dust. The neighbors asked if the plant would smell when it went online. The company owner happily informed them that the system had already been operating for 3 months and no one noticed. The special OSU design created no noise and no odor.
City treatment plants need to assess a surcharge to companies, like food processors, that discharge high-strength wastewater. The cost is justified, as their wastewater can be difficult to treat. Before they could connect to the city system, the meat processor would need to remove most of the fat from the wastewater, by constructing and operating a pre-treatment plant. Those expenses would be in addition to paying a surcharge of $10.56 for every 1,000 gallons they sent to the city plant.
Instead, the sand bioreactor system developed by OSU does not require pre-treatment to remove the fat. The system was specially designed to treat the high-strength, high-fat wastewater as is. After operating the plant for seven years now, the costs to build and operate the sand bioreactor system are $3.90 per 1,000 gallons.
Not only was the sand bioreactor system one-third the cost, it also works extremely well. The plant meets or exceeds all of the permit limits imposed by Ohio EPA. The clear treated wastewater discharges to a recreational river.
Through industry, university and government agency cooperation, a win-win-win solution was developed. The environment is protected, university students and faculty learned and developed a new treatment approach and the company saved jobs and money.
To find out more about rural wastewater treatment check the website for the Ohio State University Soil Environment Technology Learning Lab at setll.osu.edu.
Karen Mancl is a Professor in the Ohio State University Department of Food, Agricultural & Biological Engineering. This column is provided by the OSU Department of Food, Agricultural and Biological Engineering, OSU Extension, Ohio Agricultural Research & Development Center, and the College of Food, Agricultural and Environmental Sciences. For more information, Mancl can be reached at 614-292-4505 or Mancl.firstname.lastname@example.org.