Separating and dealing with oil and grease waste is an important and often challenging aspect in commercial food service design. Highland Tank has been on the front lines of this battle for almost 30 years.

Plumbing Engineer recently spoke to Charles Tevis, division manager of Grease Removal Systems at Highland Tank. Tevis shared his thoughts about the different types of grease abatement strategies and how they function in different applications.

PE: Can you tell us a little about the history of Highland Tank?

CT: Highland Tank has been manufacturing steel storage tanks in the United States since 1946. In 1986, we entered the era of wastewater treatment, manufacturing oil/water separators to meet the EPA Guidelines. Highland moved into the FOG abatement industry in 2001 when we purchased Lowe Engineering. There are six manufacturing facilities, which manufacture fuel and chemical storage tanks, oil-water separators, oil-sand interceptors, grease interceptors, water storage tanks, ASME pressure vessels, propane storage tanks, etc. Highland tank is unique in many ways, but our willingness to engineer and manufacture customized products for different applications sets us apart from many of our competitors.

PE: You note three main types of grease abatement: traditional point of use, automatic, and large volume. Is there pretty equal distribution of use between those three types?

CT: The preferred method of grease abatement varies based on the authority having jurisdiction (AHJ). For example, New York City food service establishments (FSE) typically install point of use grease interceptors, sometimes referred to as grease traps due to useable space and cost. The State of Connecticut requires by code that all interior grease interceptors to be of the automatic grease removal type. In Las Vegas, they prefer large underground grease interceptors with sample boxes. However, the Atlantic City Casinos require large automatic grease interceptors. Meeting the AHJ requirements and clients’ concerns should be the determining factors in selection of the grease abatement system.

PE: If there is one method that is more commonly used, why do you think that is?

CT: Traditional point of use grease interceptors are common based simply on upfront cost. Often overlooked is the maintenance cost associated with properly maintaining this type of grease interceptor. One of the benefits of this type is they are closer to the source providing protection to the building drainage system.

Automatic grease interceptors are used to reduce or eliminate maintenance cost. They, too, are typically located closer to the source providing protection to the building drainage system.

Large volume exterior underground grease interceptors are used to reduce maintenance frequency, however add upfront cost and provide little protection to the building drainage system.

PE: Can you give examples of different applications where one of each of the three types of grease abatement might be best suited?

CT: Traditional point of use grease interceptors are common for small food service establishments (FSE) with simply a 3-comp sink.

Automatic grease interceptors should be considered in small to medium sized food service establishments to reduce costly maintenance fees or in cases where the location of the interceptor is a challenge for maintenance. An example is if the kitchen area is located a 100 feet or more internally from the service point. Large volume exterior grease interceptors are common for medium to large sized food service establishments

PE: What does Highland Tank offer (products, services, etc.) for each type of system?

CT: Highland Tank offers all types of grease abatement systems. Interior, exterior, aboveground, underground, large, small and automatic grease removal systems to meet AHJ requirements. Highland Tank offers systems with monitors to alert personnel of required maintenance, pumps to transfer grease or wastewater, controls, etc. Other optional equipment associated with grease abatement includes sample boxes, distribution boxes, heat trace, solids interceptors and lift stations.

PE: Do you recall any horror stories of situations where grease abatement wasn't handled well?

CT: Most failures occur due to lack of maintenance. Other contributing factors include sizing, location and design. Gravity flow to grease interceptors is always best. Pumping kitchen waste into a grease interceptor should be avoided.

Grease interceptors should be located to allow for ease of maintenance. Avoid underground grease interceptors that exceed 20 feet to the bottom of the interceptor. Avoid long distances to the grease interceptor, which would promote blockages and deep burial depths.

PE: Are there any success stories you are most proud to have been involved with?

CT: Highland Tank has been fortunate to be in the position to solve many challenges when dealing with grease abatement. They have been known to reduce maintenance fees simply by the design of their interceptors. In other cases, they have eliminated fines being levied against the FSE, due to effluent quality. While still others, they have provided solutions for restricted space applications. Nearly every casino in Atlantic City has our automatic grease interceptors, some of which have been in operation for over 25 years.

PE: What is your outlook for 2014 and 2015?

CT: Highland Tank has been a leader in wastewater treatment since 1986. With water being an important resource, it is becoming increasingly apparent we protect this resource and our environment. The EPA has determined that sewer pipe blockages are the leading cause of sewer overflows, and grease is the primary cause of sewer blockages. Installing grease abatement systems engineered to trap fats, oils, grease and solids to the EPA guidelines, in lieu of a box, is imperative.