WHEN the monthly gas bill persistently registered about $16,000 per month, up from about $6,000 per month, Bob Young at Lafayette Sani-Wash decided to take action.
“Seeing those bills certainly got our attention,” says Young, owner of the Lafayette, Indiana, tank cleaning facility.
After having success with using waste motor oil for fuel to power a furnace in one of his barns, he thought of a plan using waste motor oil and soybean oil residue recovered from tank trailers to help heat the water for the cleaning bays.
Before recovering the soybean oil, Young was paying to have the product hauled off for disposal. To implement the plan using the oil, he purchased a waste oil heater from Clean Burn and installed a 1,200-gallon stainless steel tank to hold the hot water. The soybean and motor oils are stored in individual tanks with 600-gallon capacity each.
Water in the tank is preheated to approximately 70° F by using the condensate recovered from the system and another heat exchanger. It is then circulated through the Clean Burn system at 25 gallons per minute, achieving a 20° F rise on every pass.
“With this system we get a low fire versus a high fire,” says Young. “With a low-fire system, it is like the engine of your car in idle versus running full bore. When we don't hear the system running full bore, we know we are saving money. It also ensures that all the water is 180 degrees when used for tank cleaning.”
While motor oil can be burned as is, soybean oil is prepared by being heated with the steam coil in the Clean Burn system.
“Burning soybean oil is not without problems,” Young says. “It is slimy and collects on the equipment. That's why we are thinking about making biodiesel by adding methanol alcohol and caustic to the soybean oil. That would remove the glycerin. The resulting fuel would burn cleaner and eliminate the slime that clogs up our present unit.”
Young isn't sure yet how much money he is saving, but will have better calculations after the system has been online longer. He does concede that it will take several years to get the payback involved in the equipment purchase.