What Is A Grease Trap?
A grease trap is a appliance that is used to collect and remove solid material and especially fat, oil and grease (FOG’s) that could enter the sewers from your kitchen. They should only have wastewater from kitchens flowing through them. No other wastewater from other drainage system sources, such as toilets, should be allowed. Removing FOGs, can reduce the number of drain blockages you might suffer and also prevent huge fatbergs in the main sewer system, bad smells, disruption in the street and possibly pest infestations. You can find out more about them here.
There are two types of grease trap: above or below ground.
How Does A Grease Trap Work?
When the waste water from your kitchen enters the trap, it flows first through a sediment basket which removes larger solid particles. The grease in the water is less dense (“lighter”) than water and doesn’t mix with it, so it floats to the top (see this diagram).
Grease traps have to be cleaned regularly to remove these FOGS, otherwise, they build-up, and can eventually overflow through the outlet and even back-up through the inlet. Special cleaning materials can be used to reduce or prevent FOG build-up in internal piping. You should check whether these are allowed in your area, before using them. Not all water authorities allow their use.
GREASE TRAPS FOR COMMERCIAL KITCHENS
A large amount of fat, oil and grease (FOG) is produced by commercial kitchens and food establishments in the UK every day. If left untreated or not removed before joining the main sewage system, it can cause major issues with main sewers and a huge amount of disruption to businesses as it is cleared. In the UK, it is a legal requirement to install a suitable grease treatment system for effective FOG removal from wastewater from commercial hot food premises.