A privately held snack-food manufacturer in the Midwest expected to increase production of potato chips by 20 percent, to about 72 million pounds a year. While more potato chips would mean more profits, it also would mean more oil-laden wastewater from washing the potatoes and the fryers used to cook them.
When operators clean the fryers used to make the chips, oil mixes with the wash water, which is discharged into the municipal water-treatment system. The plant, in a small village, is one of the municipality's largest water consumers, discharging an average 180,000 gal/day. The company wanted to install an oil-recovery system to reduce the amount of oil in its wastewater and improve its machinery's efficiency. However, the plant's 4' dia wastewater pool is in a cramped area crowded with pipes and other equipment, which limited the space available for additional equipment.
To address the company's concerns, Cleveland-based Oil Skimmers Inc. modified its standard mounting system to fit into the tight space and installed a Model 6V oil skimmer.
"We can build something to do whatever is required for that customer in that application," says Rob Fiorilli, Oil Skimmers’ eastern region sales manager. "In this case, we built a system for them that they were able to incorporate in a small, confined area."
With its anti-clogging design, the Model 6V has a polyurethane tube that attracts and collects waste oil as it floats on top of wastewater. The tube passes through a scraper system to remove the oil, which flows by gravity into a containment drum. Since installation, the unit has been removing about 2,000 gal of oil a week from the wastewater system, bringing the following benefits to the potato chip maker.
- Cost. The wastewater requires less treatment before it enters the municipal system, reducing energy, labor and chemicals. Also, sludge-removal hauling costs have fallen 30 percent because the wastewater treatment produces less sludge.
- Improved Asset Performance. The plant’s dissolved air floatation system works more efficiently. According to the company, filter-press performance has increased, requiring less operator time cleaning the press. Additionally, loading on bioreactors where the water is treated has been greatly reduced, improving efficiency.
- Decreased Material Waste. The manufacturer has found a market for the discarded oil, using companies that make biofuels, thereby keeping about 8,000 gal of discarded oil out of landfills each month.