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Hello blog readers,

We often get asked when grease traps should be emptied.  Below is a list of frequently asked questions and answers.

When should a grease trap be emptied?

Trapping grease isn’t rocket science however there are many misconceptions about just how they operate and when they should be emptied. So lets deal with a few assumptions

“Grease Traps Should be empty only when full”

Wrong. Grease Traps need to be emptied long before they are physically full of grease. In fact a grease trap starts to allow grease down the drain when it is around 25% full of grease.

“it’s impossible to know when to empty a grease trap on time”

Wrong, though it isn’t always obvious. There are sensors available that tell you when grease traps need emptying those these can prove costly and unreliable. Most grease traps need emptying twice a month. This can also prove costly so a better understanding of a grease trap may help you extend the frequency of pump outs. A typical restaurant can produce 2 litres of grease and sludge a day. In a 100 litre grease trap. So every two weeks is about right in that case. If the same application has a 200 litre grease trap then once a month is probably sufficient. That said, it depends on the number of meals per day and in many cases the type of food being served.

“Grease Traps stink”

Not always. In our experience the number one cause of smell is failure to maintain or desludge a grease trap. Bacteria builds up on waste left over time. Think of your fridge when something stays too long in there. It doesn’t happen over night but it can happen. Most grease traps are well sealed but even the best sealed grease traps cant hide smells forever. Emptying the grease trap periodically is essential.

“I have an automatic grease trap, I don’t need to empty it”

Wrong. Automatic units remove around 95% of free-floating grease every day. Some grease remains in the tank as does some fine sediment. The unit should be fully emptied once or twice a year. Some authorities prefer this to be done every three months.

“I use enzymes/bacteria so I don’t need to empty my grease trap”

Wrong. First check that the brand or method you are using is permitted by the municipality. Bacteria tries to digest grease whilst enzymes try and emulsify it to allow it to escape. Even the leading suppliers of bacteria admit that they can only successfully manage 70% of the waste. Taking them on their word that still means 30% is left behind. Such traps still need emptying every 2 to 3 months.

“Nobody checks whether I empty my grease trap or not”

Not for long. Some local authorities are more proactive than others. Dublin City for example operate an inspection scheme whereby grease trap maintenance is regularly checked and records must be retained as evidence. Other cities wait until there is a problem and then use cameras in the drains to trace the problem back to the source. Damage caused by grease to drains and wastewater treatment equipment is in the millions. Cities everywhere are getting more proactive and a lot stricter when it comes to pollution below ground level. Everyday a restaurant somewhere gets closed down because of grease, don’t let it be yours.

Worried about your grease trap?

We can help. Send us the following information and we can let you know exactly what you need to do

  • Location (City)
  • Type of establishment
  • Estimated meals per day if applicable
  • Type of grease trap used if any
  • Size (roughly) of grease trap
  • Current emptying frequency of grease trap

For more on grease traps visit www.greaseguardian.com

Email: sales@greaseguardian.com

Product Catalogue: www.greaseguardian.com/product-range-brochure

Phone Number: +44 (0)28 302 66616

See you again next week!


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