Kitchen Drainage Systems

In most food service operations waste water is removed from the kitchen...

16th Jan 2017

In most food service operations waste water is removed from the kitchen / wash-up areas via a 50mm waste pipe system that discharges to a 110mm pipe. A grease trap is usually fitted either at the source in the wash-up area, before entering the main sewer line or underground, outside the kitchens, before the sewer line connects with effluent flowing from toilets. The purpose of the trap is to separate and trap the oil and grease, together with any foreign articles such as cloths, cutlery etc. before they enter the sewage system, in order to prevent blockages. Should a grease trap be installed?

If oil or grease is used in an establishment it will get washed into the sewage system therefore a grease trap should be installed. It is possible to install an automatic dosing pump to treat the drain lines directly, but this is an expensive and much less satisfactory option. Large amounts of oil or grease in the waste water causes trouble in the collection system pipes and the wastewater treatment plant. It decreases pipe capacity and results in pipe systems needing to be cleaned more often or even replaced sooner than expected.

Problems caused by wastes from restaurants and other grease producing establishments have served as the basis for regulations governing the discharge of grease materials into the sewer system. Consequently the installation of grease traps and grease treatment facilities are usually recommended. What if a grease trap is not installed?

If an establishment uses oil or grease in food preparation and does not have a grease trap there is a high risk of an eventual drainage maintenance problem because of a blocked building sewer line. This blockage can create sewer back up problems and ultimately a health hazard in the establishment. If the blockage is in the establishment itself, the owner will have to pay for clearing it. If the problem is in the main public sewer system and it can be traced to the establishment, the owner could be held responsible for the maintenance requirements of the public sewer. A grease trap, combined with managed maintenance is an assurance that adequate precautions are in place to prevent blockages in either case.