Grease Trap Waste (GTW)
A grease trap is an engineered tank designed to remove Fats, Oils and Grease (FOG) and food-based solids and debris from food service establishments’ waste streams, preventing their entry into sewage collection networks. The grease trap captures those wastes and contains them until a waste hauler/pumper service can collect and properly dispose of them.
Grease Trap Waste Disposal
Grease Trap Waste (GTW) is typically transported to and dumped at receiving stations which are located at a relatively few municipal sewage plants (POTWs), where they pay an average tipping fee of $0.10/gallon (US data). While very few companies have land application permits allowing for incorporating the waste into soil, this practice is discouraged for several environmental and sanitation reasons. Some haulers dewater the waste, splitting it into sewered and landfilled streams. This is both costly and labor intensive, and used only when other methods are very expensive regionally.
FOG – Fats, Oils and Greases
FOG is the collective term for the by-product of food preparation and dishwashing consisting of animal fats (lard), vegetable oils, and cooking grease. This product is commonly labeled “brown grease” in the industry. The traps that capture FOG are often neglected, which allows FOG to pass through into the sewer systems. Three-quarters of the sewage collection infrastructure in the U.S. is so clogged or damaged by brown grease that they work at half capacity, causing 40,000 sewage spills per year. According to the Wall Street Journal (June 2001), local governments spend $25 billion a year to remediate grease-related issues to keep the sewers flowing. Municipalities are cracking down on grease trap neglect, so there is a growing need for cost-effective GTW treatment. Also growing is a significant economic opportunity: FOG contains the same BTUs as diesel fuel, burns clean, and qualifies as a bio-fuel created from biomass. It substitutes for #6 fuel oil (bunker fuel) and can also be used as a poultry-feed additive.