Fats, oils and grease blockages

Date: 13/06/19 | In: Industrial Wastewater

Fats, Oils and Grease (FOG) come from food products such as butter, lard, vegetable oils, animal fats, meats, sauces and dairy products. FOG is typically generated during the preparation of food containing these products and from associated cleaning/washing up processes .Blockages in sewer networks caused by fats, oils and grease are a major environmental, operational and financial headache for water and sewage companies (WASCs) across the UK.

Why are fats, oils and grease (FOG) such a problem?

Over the last two decades, our eating habits have changed significantly. We eat out far more and the number of restaurants, cafés and takeaways has consequently increased to meet demand.

In line with the growing amount of food outlets, the waste that each catering business produces has also grown. Fats, oils and greases are commonplace in any commercial kitchen, irrespective of its size, and, once they have served their purpose such as the oil used for frying chips, they are often disposed of straight down the sink into the drain.

This oil from a chip fryer goes down the drain in liquid format straight into the public sewer. When it begins to cool, it congeals and hardens. Over time, this hardened fat sticks to the inside of drainage pipes and the sewer walls themselves and the flow of wastewater is restricted. Such restrictions can cause pipes and whole stretches of sewers to block completely which, in turn, can cause other part of the sewer to flood resulting in damaging spills and pollutions.

The blockages caused by the build-up of FOGs are expensive and time-consuming to tackle for both the business owner but also the WASC. And the potential environmental harm a spill or pollution from a flooded sewer can deliver can be irreversible.

Disposing and dealing with fats, oils and greases responsibly

It is imperative, therefore, that any FOGs your business uses or creates are disposed and dealt with responsibly to ensure that they don’t end up in the drains and public sewer network.

There are a number of different ways to achieve this including:

  • Staff training: all members of staff should have an understanding of why it is so important to ensure FOGs shouldn’t enter the drains and sewers
  • Preparation: scrape all food waste from plates, pots and utensils into a bin before washing them in the sink or dishwasher
  • Make sure every sink has a strainer fitted
  • Implement a grease trap: a grease trap can be placed into the drain pipes to trap and separate FOGs from wastewater
  • Recycle waste cooking oil: collect waste oil from any fryers and arrange for it to be picked up and turned into bio-diesel or incineration to generate electricity