F.O.G. Fats, Oils, and Grease by Dan Burke- National Waste Associates 1 Frequently Asked Questions What is FOG? Why is FOG an issue for my business? Is my business required to have a grease removal device? What is the difference between Automatic Grease Recovery Units and Interceptors? How often should devices be cleaned? What maintenance should be performed? Property of National Waste Associates 2 Defining Fats, Oils, & Grease (FOG) Organic polar compounds derived from vegetable/plant or animal sources that are composed of long chain triglycerides. Property of National Waste Associates 3 1
Food Service Establishment s FOG 2 Types Yellow grease: inedible and unadulterated spent FOG removed from FSE. Major source of yellow grease is deep frying. Put this type grease in the grease recycle bins, normally at the back of the FSE. Property of National Waste Associates 4 Food Service Establishment s FOG 2 Types Brown grease: floatable FOG, settled solids and associated wastewater retained by grease interceptors and grease traps Property of National Waste Associates 5 Yellow Grease (in recycle bin) ultimate uses: 61% Animal Feed Additive 22% Fatty Acids/Glycerol to help make surfactants, plastics, resins, textiles and cosmetics 9% Soap Making 4% Lubricants 4% Misc. (biodiesel, fuel for vehicles) Property of National Waste Associates 6 2
Major FOG sources: 90% of FOG discharged to the sewer system is from: 3 Compartment Pot wash sink Floors Pre rinse sink to dishwasher If the FSE has a pre rinse sink to the dishwasher, then there will only be 1% to 2% of the total FOG discharged to the sewer coming from the dishwasher. Many cities have in their FOG Mgt. policy to not have the dishwasher connected to the grease interceptor. This is due to high temperatures (130 to 180*F), soaps and surfactants that can allow FOG to pass through the inceptor Property of National Waste Associates 7 Fats, Oils, & Grease- Regulations Grease trap / interceptor Size of interceptor Frequency of Pumping Proof of Pumping Enzymes, digesters, and other additives Property of National Waste Associates 8 Grease Control Equipment Grease Interceptor or Outside, underground tank Grease Interceptor Means any device or equipment designed to separate fats, oils, and grease from wastewater while allowing water to flow through. Grease Trap or Inside, under the sink units, floor traps, and outdoor floor traps Property of National Waste Associates 9 3
Grease Interceptor How it Works: Property of National Waste Associates 10 Grease Interceptor Full- Needs Pumping Property of National Waste Associates 11 The Good, The Bad, The Ugly Property of National Waste Associates 12 4
Cleaning Traps Pumping & Scrapping must be performed. Property of National Waste Associates 13 Cleaning Frequency for Grease Interceptors Depends on facility s service volume Depends on size of grease interceptor At a minimum, pump complete contents of interceptor every 90 days Based on studies conducted for pollutant concentrations, depth of FOG layer and food solids layer effecting efficiency of interceptor Some facilities will have to pump every 60 days or every 30 days Make sure plumber and grease waste hauler leave the grease interceptor with all proper components Outlet T, Inlet T, Midwall baffle sweep. Its not just about pumping the interceptor For facilities that have excess flour, dough, batter will need to pump interceptor more often. Observe the 25% rule. Also, food grinders are definitely discouraged. They contribute to pipe blockages and fill up the interceptor with food solids and make it inefficient Property of National Waste Associates 14 Hydro Jetting Jetting should be done a minimum of 2 times per year. Property of National Waste Associates 15 5
Interceptor Pumping Pump complete contents of interceptor WHY? Studies have shown that partial pumps of interceptors allow for food solids buildup that can cause short circuiting and increase in the tank deterioration, ti and decrease in ph. Pump and treat t onsite vendors have been sampled and results show a pump back wastewater with concentrations ranging from 9,000 mg/l to 17,000 mg/l oil and grease. Pump at least every 90 days or as needed in order to meet the 25% rule (FOG layer and food solids layer combined are 25% or more of the total wastewater depth in the interceptor) Property of National Waste Associates 16 Cost of Interceptor Maintenance Example: FSE pumps 1500 gallon interceptor every 10 months. Thus, heavy FOG layer and food solids layer. This causes the grease waste hauler to spend much more time to clean which equals high cost (estimated $750 to $1500 for annual cleaning plus cost of sewer line jetting due to no regular maintenance) Versus 90 day cleaning easier maintenance and prevention of FOG clog in private sewer lines. Cost estimate for cleaning every 90 days would be $250 to $350, which is less than the one time per year cost of cleaning. Regular maintenance of interceptor will save time and money. Property of National Waste Associates 17 Liability Property of National Waste Associates 18 6
BEST MANAGEMENT PRACTICES Recycle waste cooking oil. Put in approved oil and grease recycle container. Make sure you have grease control equipment (interceptor or trap) installed, regularly maintained and operating properly. Property of National Waste Associates 19 BEST MANAGEMENT PRACTICES DO S DO scrape all food scraps and grease solids into the garbage. DO collect excess frying grease in a separate container for proper disposal. DO schedule regular cleaning for grease interceptors/traps. p DO inspect your grease interceptor/trap monthly to ensure it is working properly. DO clean up grease spills with absorbent material (e.g. cat litter) and put into dry trash. DO clean hood filters, floor mats, fry racks, etc. inside your kitchen. DO dispose of mop water and carpet shampoo wastewater into your mop sink. Property of National Waste Associates 20 BEST MANAGEMENT PRACTICES DON TS DON T rinse off food scraps and grease from plates, pots and pans using hot water and flush down your kitchen drain. DON T pour FOG (salad oils, butter, shortening, grease, cooking oil, soups) p) down your kitchen drains. DON T put enzymes or other additives directly into grease interceptor/trap in order to reduce cleaning schedule. DON T wait for city inspectors to tell you to clean you grease interceptor/trap. DON T use water to spray down grease spills into an outside drain. DON T clean greasy equipment outside. DON T dump mop water or carpet shampoo wastewater outside. DON T get lost in the FOG. Property of National Waste Associates 21 7
Fats, Oils, & Grease (FOG) Questions? Property of National Waste Associates 22 8