Sludge Transport and/or
Disposition Equipment or Services
Challenging Mix of Oil and Glycol Finding the most effective, reliable and econom- ical method for separating and concentrating die lubricant is no easy task for die casting plants – and the situation at the Metaldyne alu- minum die casting plant in Twinsburg, Ohio was no different. For over a decade, Bill Cleary, the wastewater treatment manager, worked with 22 different wastewater treatment vendors, in addition to experts from academia and the U.S. Department of Energy to find the optimal solution for his plant.
The Twinsburg Plan is a world leader in the production of aluminum valve body castings. To facilitate this process, Metaldyne has devel- oped a world class die casting process that uti- lizes a specially-formulated die lubricant, an oil and water emulsion, which helps control the temperature of the die as well as the removal of the complex castings during the part ejection process.
Each cycle of the highly-automated process begins with numerous nozzles spraying a con- trolled volume of lubricant onto specific loca- tions on the die. Next, molten aluminum, at 1,250°F, is auto-ladled into the cold chamber and injected into the die under high pressure. The plant’s drainage system collects the waste generated from the casting process, including the die lubricant, as well as detergents from washing operations and glycol from the hydraulic fluid used in the robotic machinery. In addition, some process cooling water and cooling tower bleed are piped into the waste- water treatment system. The total combined wastewater flow is 9,000 to 11,000 gpd, with chemical oxygen demand (COD) ranging from 20,000 to 40,000 mg/l. Clogged MBR and High Disposal Costs “The oil from the die lube and the glycol from the hydraulic fluid combine to create an extremely difficult wastewater treatment chal- lenge,” explains Bill Cleary. “We cannot use flammable hydraulic oil because of the high temperatures of the molten metal. Instead, we use glycol which, must be removed to meet our COD discharge limits.”
The plant’s original physical-chemical waste- water treatment system performed poorly, because it was difficult to maintain a consis- tent recipe. This situation was further compli- cated by the uncontrolled and unpredictable flow rate and the difficult composition of the wastewater stream.
In 1995, the plant installed a bioreactor system to consume the glycol. The membrane bioreac- tor (MBR) system was arranged with the tubu- lar membranes external from the bioreactor,
WedgeWireorTubeSettlers
Air Flotation Systems
Return Activated Sludge or
Bioaugmentation
Dredges
Sludge Spreading
Sludge Containers
Sludge Conveyers
Sludge Hauling
Thickeners
Clarifiers
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Brown Bear Corp.
641/322-4220
Carylon Corp.
800/621-4342
Cemen Tech Inc.
515/961-7407
Cetco Lining Technologies
847/851-1800
Converto Mfg. Co. Inc.
765/478-3205
DBS Manufacturing Inc. ; ;
404/768-2131
Dorr-Oliver Eimco ; ;
801/526-2000
Ellis Corp. ;
630/250-9222
Exair
513/671-3322
Flo Trend Systems Inc.
713/699-0152
Goodnature Products Inc.
716/855-3325
Gorman Rupp Co.
419/755-1011
www.grpumps.com
Hydrocal Inc. ;
949/455-0765
International Reserve Equip ; ;
630/325-7040
JWC Environmental
949/833-3888
Komline-Sanderson ; ;
800/225-5457, www.komline.com
Kontek Ecology Systems Inc. ; ;
877/332-8366, www.kontekecology.com
Liquid Waste Technology LLC ;
800/243-1406
Markland Specialty Engineering
905/873-7791
www.sludgecontrols.com
Mixing Systems Inc.
937/435-7227
Mt Fury Co Inc.
475/391-0747
Nasco ;
910/563-2446, www.enasco.com
Netzsch
610/363-8010
Pacific Press Co
714/525-0630
Parkson Corp. ; ;
888/727-5766
Phoenix Process Equipment Co. ;
502/499-6198
Polychem Systems ;
484/651-1417
Pro Equipment Inc. ; ;
262/513-8897
SRS Crisafulli Inc.
800/442-7867
Seepex Inc.
937/864-7150, www.seepex.com
Serfilco Ltd.
847/509-2900
Smith & Loveless Inc. ; ;
913/888-5201
www.smithandloveless.com
SSI Shredding Systems
503/682-3633
Vaughn Company Inc.
888/249-2467
Viatran Corp.
716/773-1700
Westech Engineering Inc. ; ;
801/265-1000
Z M I/Portec Chemical
712/754-3607
Manufacturer
Flocculant Systems
Centrifuge Units
Sludge Handling
or Treatment
Supplemental Equipment
Dredges
Clarifier or Thickener Drives
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KEY: CF Chemical Fixation Units HD Heated Dryers thus separating the water from the activated sludge. The effluent from the MBR was polished by a reverse osmosis (RO) system, prior to discharge into the municipal wastewater system .
Unfortunately, the tubular membranes in the MBR had difficulty handling the oils and greases, resulting in clogged pores in as little as three weeks. A scum, with a consistency of a foamy milkshake, formed on the top of the biore- actor tanks, often overflowing onto the floor. The die lube, which accounted for approximately 80 percent of the waste stream, seemed to be the source of the problem.
