The Johnson County Wastewater Department in Kansas received $18.2 million in funds from the American Recovery and Reinvestment Act to make improvements to the Douglas L. Smith Middle Basin Treatment Plant in Overland Park. The improvements will enable increasing the production of natural gas and include the construction of an anaerobic digester; a station for receiving fats, oil and grease from restaurants and industries; and a cogeneration system. The biogases produced will supply virtually all the plant’s operating energy.
As reported by Sun Publications, the improvements support the commitment of the Johnson County Board of County Commissioners to reduce greenhouse gas emissions from county facilities 80 percent by 2050. The fats, oils and grease will go into anaerobic digesters, along with sludge from the wastewater treatment, to produce natural gas.
According to the Sun Publications report, adding the fats, oils and grease will double or triple the production from the new cogeneration system. It is estimated that the system will reduce the county’s utility costs by $540,000 a year and will avoid the emission of 9,600 metric tons of CO2 equivalent each year. Providing a receiving station for the fats, oils and grease from local restaurants and industries will also avoid the need to haul them outside the county, saving an estimated 8,000 gallons of diesel a year.
In an article on the Water and Wastewater website, Linda Bond explains that the improvements in the Douglas L. Smith Middle Basin Treatment Plant will have additional environmental benefits in terms of water quality. The expansion increased the treatment plant’s capacity from 12 to 14.5 million gallons per day and the plant is among the first in the Kansas City metropolitan area to use biological nutrient removal to reduce the discharge of phosphorus and nitrogen. In her article, Bond quotes John O’Neil, general manager of Johnson County Wastewater, as indicating that removing the phosphorus and nitrogen will have benefits through the water stream all the way to the Gulf of Mexico, by reducing problems related to oxygen deficiency.
Ted J. Rulseh reported for the Treatment Plant Operator Magazine that the Douglas L. Smith Middle Basin Wastewater Treatment Plant Solids Improvements Project earned a National Environmental Achievement Award from the National Association of Clean Water Agencies. In addition to the environmental benefits of reducing CO2 equivalent emissions by producing gas to run the plant from local fats, oils and grease that would otherwise be trucked away, the reduced biosolids produced in the process can be recycled as a soil amendment on farm fields. The project is also credited with creating or retaining more than 270 construction jobs.
Chuck Kurtz, “County treatment plant will use discard oils to produce gas” – Sun Publications
Go Green: Turning wastewater into green energy – Sun Publications
Linda Bond, “Benefits of WWTP Upgrade Reach Beyond Local Streams” – Water and Wastewater
Ted J. Rulseh, “Kansas biosolids project wins major award” – Treatment Plant Operator Magazine