Avoid Grease Trap Problems With Proper Maintenance

A grease trap (also known as grease interceptor, grease recovery device and grease converter) is a plumbing device (a type of trap) designed to intercept most greases and solids before they enter a wastewater disposal system. Common wastewater contains small amounts of oils which enter into septic tanks and treatment facilities to form a floating scum layer. This scum layer is very slowly digested and broken down by microorganisms in the anaerobic digestion process. Large amounts of oil from food preparation in restaurants can overwhelm a septic tank or treatment facility, causing release of untreated sewage into the environment. High-viscosity fats and cooking grease such as lard solidify when cooled, and can combine with other disposed solids to block drain pipes.

Restaurant and foodservice kitchens produce much waste grease which is present in the drain lines from various sinks, dishwashers and cooking equipment such as combi ovens and commercial woks. If not removed, the grease can clump and cause blockage and back-up in the sewer.

In the US, sewers back up annually “an estimated 400,000 times, and municipal sewer overflows on 40,000 occasions”. The EPA has determined that sewer pipe blockages are the leading cause of sewer overflows, and grease is the primary cause of sewer blockages. Even if accumulated FOG does not escalate into blockages and sanitary sewer overflows, it can disrupt wastewater utility operations and increase operations and maintenance requirements”

For these reasons, depending on the country, nearly all municipalities require commercial kitchen operations to use some type of interceptor device to collect grease before it enters sewers. Where FOG is a concern in the local wastewater system, communities have established inspection programs to ensure that these grease traps and/or interceptors are being routinely maintained.

There are three primary types of devices. The most common are the types specified by ASME (American Society Of Mechanical Engineers), utilizing baffles, or a proprietary inlet diffuser.

Grease trap sizing is based on the size of the 2- or 3-compartment sink, dishwasher, pot sinks, and mop sinks.

The second most common type of interceptor is the large in-ground tank, which is usually 500–2,000 US gallons (1,900–7,600 l; 420–1,670 imp gal).

A third system type, GRDs (grease recovery devices), removes the grease automatically when trapped.

Passive grease traps and passive grease interceptors must be emptied and cleaned when 25% full. As the passive devices fill with fats, oils, and grease, they become less productive for grease recovery. A full grease trap does not stop any FOG from entering the sanitary sewer system. The emptied contents or “brown grease” is considered hazardous waste in many jurisdictions. “Brown grease” is generally not recycled and goes to landfill waste.

It is estimated 50% of all sewer overflows are caused by grease blockages, with over 10 billion US gallons (3.8×1010 l; 8.3×109 imp gal) of raw sewage spills annually.

Avoid grease trap problems, a proper maintenance and routine cleaning is important to keep drains flowing smoothly and prevent major problems from happening in your home or restaurant.

Information by Wikipedia