by Mike Miazga
June 20, 2011
Two AGI-200 interceptors skim grease off the water at a rate of 40 lbs./hr. This type of grease interceptor is experimental in Phoenix. Photo courtesy of Highland Tank.
New grease interceptor technology aids Phoenix commercial development.
Downtown Phoenix features a new mixed-use commercial development that stretches two city blocks near Chase Field, the home of the Arizona Diamondbacks baseball team.
The expansive development includes a Lucky Strike bowling alley, an Arrogant Butcher restaurant, a Napa Valley-themed grocery store, and a Five Guys Burgers and Fries eatery. Various other retail outlets dot the property.
The presence of multiple food-service establishments meant an efficient solution for the removal of fats, oils and grease was necessary. In similar commercial developments, underground grease interceptors serve multiple food-service establishments. That proved infeasible in this instance due to the requirement of long pipe runs.
Phoenix-based WJ Maloney Plumbing, along with Highland Tank and its local representative Applied Process Equipment, decided to still head underground, in a sense, to solve the grease issue. The companies designed and specified a plan calling for the installation of multiple interceptors in a parking garage on the property.
“Phoenix is red-hot and heavy about keeping grease out of the city systems,” WJ Maloney Plumbing Project Manager Alan Boughton, LEED AP, says. “Without the units we put in, the restaurants wouldn’t go in and that property wouldn’t fly. The parking garage was the best place to put them.”
Block 22 on the property houses a 5,000-gallon Highland Tank interceptor, which caused the elimination of two parking spaces. A 3,000-gallon interceptor will be installed later this year to coincide with the future opening of the chic Kimpton Palomar hotel.
The cutting-edge part of the solution is located in Block 77 of the property and features two Highland Tank AGI-200 GreaseStoppers. The AGIs differ from larger interceptors due to smaller retention capacity and the ability to physically separate grease from water. This particular AGI interceptor has a static water capacity of approximately 350 gallons and features diskimmer wheels that slowly turn and skim grease off at a rate of 40 pounds per hour.
“It holds the grease until it fills up and then pumps it out into a 55-gallon drum,” Boughton explains. “There’s a bigger 100-gallon drum on the first level. When the drum fills up, you take it away and put a new one in. It’s experimental and it’s very cost-effective. They take up far less room than the passive interceptors. There are only three of them in the city. They allowed them in Block 77 to see how they perform. The city wasn’t ready to go all the way with them.”
Currently, two food-service establishments feed into one of the AGIs and a single food-service establishment goes to the other. Block 77 also contains a Highland Tank 1,500-gallon passive interceptor that sits above ground on saddles and is equipped with heat tracing and an electric immersion heater to keep grease from congealing. A built-in lift station chamber fitted with a duplex pump package lifts effluent to the required higher elevation.
In terms of flow, central lines come through the core of the structure into each food-service establishment and then run across the parking lot to the interceptor. The 5,000-gallon interceptor is located below grade and has to pump up to a discharge line.
The design of the system is set up to handle the addition of future establishments requiring FOG removal.
“The trunk lines are all in,” Boughton states. “It’s just a tee off the line to the various retail spaces. We’re just waiting for restaurants to come into spaces. Seven are there right now and I believe another five or six are coming online.”
While it may seem odd to utilize a parking garage for the storage of the interceptors, it turned out to be the perfect solution in this space-challenged setting.
“Gravity and space were not on the side of the clients,” Highland Tank Division Manager Chas Tevis states. “Locating the grease interceptors on the sidewalks of a busy downtown area was simply not an option. Grease interceptors tend to smell, especially when being serviced. It was not practical to use point-of-use interceptors in this application. Each food-service establishment would require two to four interceptors. They had very few options. They needed grease abatement and this solution provided that.”
An interceptor retrofit has helped with the bottom line at Elmer’s restaurant in Pocatello, Idaho. Photo courtesy of Earl Coffman.
Mike Miazga
miazgam@bnpmedia.com
Mike Miazga is the senior editor of pme. He can be reached at 847/405-4056.
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