Plumbing codes state grease interceptors shall be provided to prevent the discharge of fats, oils, grease, and other substances (solids) harmful to the public sewer, the private sewage system, or the sewage treatment plant or processes. This applies to several types of food service establishments such as restaurants, cafés, schools, colleges, universities, medical facilities, correctional facilities, malls, stadiums, arenas, convention centers, casinos, etc.
When the sewer system, which conveys wastewater, including human waste, overflows, this event is known as a
sanitary sewer overflow (SSO). The EPA’s Report to Congress on sanitary sewer overflows identifies that grease is the most common cause of blockages. The National Pretreatment Program provides authority to state and local publicly owned treatment works to reduce or eliminate sanitary sewer overflows. One method of enforcement is effluent quality. The EPA identifies an effluent quality of 100 mg/l as a common pretreatment limit. The type of grease interceptor varies based on the client’s needs, site restrictions, number and type of drainage fixtures, authority having jurisdiction, etc.
Highland Tank is the leading manufacturer of grease interceptors. Point of use hydromechanical grease interceptors are designed to be installed indoors, closer to the source. These are designed to protect the building’s drainage system as well. These systems require routine maintenance. The automatic grease interceptor is designed to reduce costly maintenance fees. Constructed of 304 stainless steel with integral solids interceptor, the automatic grease
interceptor skims grease into an adjacent grease storage container on a daily basis. Automatic grease interceptors are available in on-floor models or flush-in-floor. The other types of grease interceptors are passive grease interceptors.
Typically located outside of the food service establishments, further from the source, they are designed to operate on retention time for separation. Since they are larger in volume, generally about 500 gallons and greater, they require less frequent maintenance. The Highland Tank PGI series grease interceptors offer a superior warranty to traditional
concrete grease interceptors and most importantly are engineered to produce superior effluent quality. These are most commonly installed underground but are also available in above ground models occasionally found in parking
garages.
