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ETV REPORT - EVALUATION OF DAVIS TECHNOLOGIES INTERNATIONAL CORP. - INDUSTRIAL WASTEWATER TREATMENT PLANT
Citation:
Concurrent Technologies Corporation (CTC). ETV REPORT - EVALUATION OF DAVIS TECHNOLOGIES INTERNATIONAL CORP. - INDUSTRIAL WASTEWATER TREATMENT PLANT. U.S. Environmental Protection Agency, Washington, DC.
Description:
Abstract: Evaluation of Davis Technologies International Corp. Industrial Wastewater Treatment Plant
The Davis Technologies International Corp. (DTIC) Industrial Wastewater Treatment Plant (IWTP) was tested, under actual production conditions, processing metalworking and metal finishing wastewater, at Federal-Mogul, Inc., in Blacksburg, Virginia. The verification test evaluated the ability of the IWTP system to remove regulated contaminants from the wastewater.
The IWTP system that was tested is a mobile unit with a flow capacity of 38 to 246 liters/min (approximately 10 to 65 gallons per minute (gpm)). This system is designed to treat various types of industrial wastewater. When used to process a combined oily and metal-bearing wastewater, the IWTP system consists of two separate processes, oil recovery and metals precipitation, and each process consists of three stages. In the first stage of oil recovery, the hydrocarbon (oil) is cracked via a pH adjustment with hydrochloric acid (HCI). The second stage is flocculation, where a proprietary polymer is added that captures the hydrocarbons in a floc. In the third stage, dissolved air is ir@ected into the wastewater, forcing the flocculated material to the surface, where it is skimmed off and pumped to a collection tank. The metals treatment process is also conducted in three stages. In the first stage, the pH of the wastewater is adjusted using sodium hydroxide. This causes metals to precipitate in a hydroxide form. In the second stage, ferric chloride (acting as a coagulant) and a proprietary polymer are added, which causes precipitated metals to agglomerate in a dense floc. In the third stage, air is injected into the wastewater, forcing the flocculated material to the surface, where it is skimmed off and pumped to a collection tank.
The test was conducted during three distinct test periods, with a different raw wastewater processed during each test run. The three wastestreams represent wastewater from three common Metal Finishing/Metal Products and Machinery category manufacturing configurations:
During the first test period, oily wastewater from metalworking operations (machining, forming, cleaning) was treated.
During the second test period, metal-bearing wastewater from metal fmishing was treated. During the third test period, a mixture of oily wastewater from metalworking and metal-bearing wastewater from metal finishing operations was treated.
The treated effluent from the IWTP system was pumped to a storage tank and fed into the existing Federal-Mogul wastewater treatment system.
ical usage, electricity usage, and sludge generation data were collected to perform the cost analysis.
The analytical results indicate that the IWTP removed the oil to near or below detection limits (1.0 mg/L) for all sampling periods. The removal percentages for aluminum, copper, lead, tin, and zinc ranged from >75 percent to 98.9 percent. During Run 3, when a combined oily and metal-bearing wastewater was treated, the IWTP removed greater than 97.2 percent of O&G (HEM).
The following parameters were considered in the cost analysis: chemical reagents, other materials, electricity, sludge management, and oil recovery. The cost of treatment was $0.88/1000 L for Run 2 and $2.21/1000 L for Run 3. The cost is based on total volumes treated during Runs 2 and 3, which were 443,663 L and 188,163 L respectively.