Oil Recovery Reduces Sewer Cleaning
Doskocil Food Service Company, a division of Foodbrands America, Hutchinson, Kan., produces 2 million pounds of pizza toppings a week. After cooking, the meat toppings are flash-frozen in one of two spiral freezers. Air currents within the freezer carry grease-containing vapors through the ammonia freezer coils, where they adhere and become lodged.
Doskocil uses 1,600 gallons of water per hour to defrost the coils. Each defrost cycle carries about 50 lbs. of grease with the water, causing an overloaded and clogged DAF (Dissolved Air Floatation) system. This was becoming a maintenance problem for the company.
Searching for a simple yet cost-effective solution, the company installed a Model 5H oil skimmer from Oil Skimmers Inc. Now the defrost water collects in a discharge reservoir, where oil separates and floats to the top, and then the Model 5H begins its job. A specially formulated polyurethane closed-loop collector tube is drawn across the surface of the grease-laden water. Oil adheres to the outside of the tube, is lifted up and out of the reservoir, then drawn through scrappers that remove the oil. Recovered oil collects in an attached container and the cleaned tube simply and continually repeats the process.
“We used to have to clean our sewer lines every month,” says Bill Hackett, maintenance engineer. “Now, we only have to do this every three months. Also, there are no shutdowns due to drain backups, and we have increased the quality of our effluent.”
Doskocil has realized an added bonus as well. It generates income by selling the recovered grease to a byproducts company. According to Hackett, the skimmer collects about 800 lbs. of grease per day; the sale of grease to the byproducts company more than paid for the cost of the unit within the first month of use.