Choosing an oil water separator for your auto shop

Cleanawater on 23 October 2019

As an auto shop owner, the focus of your business is on the repair and maintenance of vehicles. But in the process of serving your customers, you also generate oily waste. This waste doesn’t contribute to the quality of service you offer to your customers and it may not seem like a major component of your business.

However, it does impact on your trade waste agreement with your local water authority. It could also result in damage to the environment if not treated and handled in a responsible manner.

Reach out to Cleanawater for more information about oil water separators for auto shops.

Sources of oil in auto shop trade waste 

auto shop

Dealing with auto repairs and servicing naturally means that you will be exposed to leaks and spills from car engines. Each spill may be small in itself and can even be cleaned up with appropriate absorbents. But some oil and grease will still find its way into the auto shop wastewater.

Cleaning cars, engine parts and even floor areas contributes to the build-up of oil in the wastewater, which must be cleaned before discharging to the sewer.

Trade waste permits and what they require

Local water authorities require trade waste permits to be in place before auto shops can dispose of their wastewater into a sewer. This process is designed to protect the environment from damage caused by hazardous chemicals and oils.

Hunter Water, for example, prohibits the discharge of glycols or antifreeze into their sewer system. Permits are issued on the basis of wastewater flow rate, type and quantity of contaminants as well as other corporation specific requirements. Each water corporation sets maximum limits for contaminants, such as a maximum oil content. 

Local water authorities may also require the installation of an oil water separator at a site to ensure they can meet the oil content specification.

Oil water separator options

oil water separators

Cleanawater supplies two types of oil water separators: coalescing plate separators and vertical gravity separators. They operate on a similar principle, which is to allow the oil droplets to stick together, forming larger drops which migrate to the top of the separator while clean water flows out of the bottom.

Vertical gravity separators can accommodate flow rates up to 3,000 litres per hour, while coalescing plates can have a capacity of up to 50,000 litres per hour. Vertical gravity models reduce oil content down to approximately 50 ppm, but coalescing plate models are much more efficient and can reduce oil content to as low as 10 ppm.

Maintenance and servicing

Having an oil water separator for your auto shop is an important step towards compliance, but maintaining and servicing your separator is vital for its ongoing performance. Some key maintenance and service actions include:

  • Checking the silt traps and collection pits for sludge.
  • Cleaning out the waste oil container in accordance with local regulations to prevent oil carryover with the wastewater discharge.
  • Taking the oil water separator out of service every 3 to 6 months for cleaning and servicing.

Challenges of treating auto shop trade waste

Compliance is an important issue for auto shops because a lack of compliance can lead to fines and even site closures. Where local water authorities prohibit the discharge of glycol and radiator fluid, these must be contained and disposed of through certified waste disposal companies.

Besides compliance, there are also factors that can affect the performance of treatment systems like oil water separators. For example, some detergents keep oil in an emulsion form, which prevents it from rising to the surface of a separator. Only quick break detergents should be used so that this problem is avoided, and no oil escapes with the wastewater discharge to the sewer.

Contact Cleanawater for expert advice 

Contact Cleanawater for all your oil water separator needs. We have more than 20 years of experience in the Australian market and have all the expertise to help you implement a compliant oil water separator for your auto shop. Cleanawater also provides maintenance and servicing contracts to ensure your system continues to perform year after year.

Contact Cleanawater today to arrange a consultation for your oil water separator needs.