What is a grease interceptor and how does it work?

A grease interceptor is very similar to a grease trap in that it catches grease/oil and food debris from the outflowing water in a sink so that these elements do not cause sewage blockages and plumbing problems. However, a grease interceptor is not just a part that fits under the sink– it is a self-standing, much larger item. It’s commonly placed outside the establishment that uses it, underground. A trench is dug, the interceptor is lowered into it, and a concrete slab placed on top. An extension collar runs from the interceptor buried several feet below the ground to the access point at ground level. These large plumbing devices are mandatory for restaurants in many municipalities to pass building code regulations. Grease interceptors must be pumped regularly to remove the greasy sludge on top of the water (when it fills 25 percent of the interceptor’s capacity). The pump machine is attached to the access point that is connected by a sort of hose to the underground grease interceptor.

How much does it cost to install a grease interceptor?

The price range for grease interceptor installation varies widely, but the average range across the US is from 3000 to 6000 dollars. There are many factors that could push that price up or down. First, if the grease interceptor is one that has an 800 gallon capacity, it’s installation price will be different from a 2500 gallon unit. Additionally, automatic grease interceptors are much more sophisticated and expensive than gravity interceptors. Installing a grease interceptor is a more involved process than just putting in a simple grease trap. Trained professionals use a complicated algorithm. They figure out the volume capacity of each sink, adjust for water displacement, and determine the flowrate of water. That helps them select the correctly sized unit.

What is the difference between a grease interceptor and a grease trap?

Grease traps and interceptors are very similar in function but they also differ in several ways. Both essentially separate oil and grease from water. However, a grease interceptor is larger than a grease trap and can handle a higher volume of outflowing waste water: more than 50 gallons per minute, whereas the grease trap’s capacity tops out at 50 gals/minute. Also, while grease traps are directly under the sink, interceptors are located outside the building. Grease interceptors are usually necessary for restaurants, where large amounts of oil are used and discarded, while grease traps are the more logical options for homes.

Types of grease interceptors:

Gravity Grease Interceptors

These are passive interceptors that just separate the food, oil, and grease from the water as it flows down. Each unit is able to hold only a small percentage of grease in its total capacity and needs to be pumped every three months to remove it.

Automatic Grease Interceptors

These machines are able to hold much more grease within them. Automatic grease interceptor efficiency is much higher because they both stop the FOG (food, oil, grease) from entering the plumbing and sewage system and they skim it off into a separate container. Though their price is more upfront, they save the facilities that use them countless dollars over time in pumping fees.

Maximum-Retention Hydromechanical Grease Interceptors

These interceptors are more compact than the traditional units but they hold a lot more grease– about 85 percent of their total capacity. They’re often made of plastic or fiberglass that are much longer lasting than the steel or concrete most commonly used on gravity-based units.

If you’d like to install a grease interceptor for your Denver area restaurant, call Hoodbuilder at 303-777-7720.

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