Grease Collection System for Bio Diesel
By: Robert D Judson, PE

Emergent Construction Technologies designed, fabricated, and installed a grease recovery system for Odom’s Tennessee Pride, a pork processing plant. The recovery system was installed on a 6,000/lb/hr sausage cooker to collect airborne grease particles from the cooker hood exhaust and cooking grease from the cooker cooling water stream.

The airborne grease collection system is made up of a roof mounted air scrubber/demister and a skimmer tank with two tank mounted belt skimmers for floating grease removal.

The air scrubber consists of an air receiver and baffled demister screens with a steam back wash assembly. Airborne grease particles are collected from the stack exhaust on a stainless demister screen and steam back washed to a skimmer tank. Back wash is done through a PLC differential pressure monitoring system. Cooker oil-laden cooling water is recovered at the cooker discharge and reclaimed in a common skimmer tank.

Oil recovery from the two waste oil streams yield three totes of high quality “lard” a day or approximately 3,000 lbs/day. The recovered grease is sold for bio-diesel conversion. Income from grease sales is projected at $100,000/yr at a current price of $.10/lb. The efficient removal of the oil and greases from the plant wastewater stream has brought the plant’s FOG discharge to the City Municipal Wastewater plant in compliance with the City’s effluent requirements. The reduced oil loadings to the sewer has eliminated FOG wastewater surcharges and eliminated the need for a pending wastewater treatment plant.