Types of Grease Interceptors

A grease interceptor is a series of containers designed to trap fats, oils and grease before they can drain into the public sewer system and clog up the pipes. Grease interceptors are most often found connected to the sink or dishwasher of a restaurant or other high-volume commercial operation.

Function

Grease interceptors use two containers to separate the heavy grease and oils from the water. The waste water is drained into the first container, where it is allowed to cool. The grease solidifies and floats to the top of the container. The remaining water drains out through a hole in the bottom. When it reaches the second container, the same separation process occurs to pull out any remaining debris that has passed through the first container.

Types

The most common type of grease interceptor uses a small tank to hold the grease that is removed from the waste water. This setup is installed in the drainage system of an individual sink or dishwasher unit. For commercial operations, a large tank may be built into the ground to handle all of the grease disposal for the entire site. These tanks are generally made out of steel, fiberglass or concrete and can hold as much as 1,000 gallons of grease.

Size

The capacity of a grease interceptor is measured in the number of gallons of wastewater it can process per minute. The National Plumbing Code provides a table of grease interceptor sizes based on the diameter of the drain pipe that it must service. For example, a sink with a 2-inch drain pipe would require a grease interceptor that can handle at least 22-1/2 gallons per minute.

Significance

If grease, fat and oil are allowed to drain into the sewer system, they can clog up the pipes and cause the system to back up. A severe clog may even lead to burst pipes, creating expensive repairs for the local utility company. Today, most cities in the United States require commercial kitchens to install some form of acceptable grease interceptor to minimize these occurrences.

Considerations

Disposing of the grease from an interceptor's trap can be messy and cumbersome. This leads to many restaurants putting off the unpleasant task and allowing the grease interceptor to back up and spill over into the sewer line. Third-party vendors can be called to dispose of the grease and clean out the interceptor's trap. Most of these disposal companies attempt to recycle as much of the waste as possible.

References

• Grease Interceptor Guide