Oil And Grease

Oil & Grease

The highly successful SPEL fuel/oil Separators are depended on across the globe. They are the result of extensive testing by H R Wallingford, the hydraulics research testing station, for hydrocarbon removal performance against the stringent British/European Standard BS EN 858 -1. The tests required the hydrocarbons introduced into the separator at 5ml/litre to be reduced to a maximum of 5mg/litre in the outlet.

H R Wallingford started testing SPEL Separators in 1999 and the SPEL Stormceptor® class 1 by-pass separator was the first to achieve accreditation under the standard in the UK.

The current British Standard is the succession to the well respected Environment Agency document, PPG3.

Oil has long been acknowledged as one of the great polluters of both soil and water alike, and capturing these spills is still at the forefront of any good drainage design

Spillages of oil and fuel from industrial sites, filling stations and leaks from cars,. trucks and planes, have a cumulative effect that can damage the environment in devastating way. Highway surface runoff discharge contains pollutants that have accumulated on the carriageway, and if unchecked, will end up in the natural environment. The SPEL Stormceptor Class 1 Bypass Separator is designed to treat flows from large catchments such as motorways and airport hard standing, making it ideal for these types of applications.

Petrol stations forecourts and indeed any fuel handling facility rank amongst the highest risk environments for oil spills and these need to the protected by a special Forecourt Separator as a minimum. Note: drainage design for these facilities should also reference APEA’s Blue Book guidance. The range of SPEL Forecourt Separators covers fuel handling facilities from a small petrol station through to major fuel handling facilities.

Other high risk industries include sub stations transformers, major ports, and any industry handling hydrocarbon-based fluids. Oil spills in any of these sectors can cause catastrophic impact on our environment and it is the responsibility of owner/operators to ensure the correct protection is in place. The law is simple – “THE POLLUTER PAYS”. Modern transformers can hold up to 80 tonnes of cooling oil which presents a serious risk in the event of a leak. SPEL’s constant development has resulted in a range of specially designed separators for both mineral and synthetic transformer oils with single chamber, two chamber, and National Grid specification systems available.

Where the is a risk of a water soluble pollutant, or the discharge is to a foul sewer, it is possible to install a class 2 Separator. This applies particularly to any wash down facility where detergents, degreasers or other chemicals are used in the washing process. In some cases, a Class 1 separator may be required, even when discharging to the foul, please check with the relevant authority and/or water company. In most vehicle wash sites, a pre-treatment silt trap is recommended.

A major challenge for today’s sewers is the build-up of fat and grease, known as FOG (Fat, Oil & Grease). and is the cause of blockages and contamination of the sewer infrastructure. As a result, all food processing facilities are required to treat water prior to discharge with a suitable grease separator that is regularly maintained. SPEL manufactures a comprehensive range of grease trap separators designed for easy maintenance and low running costs.

Hydrocarbon Removal Performance

All models performed well within the European Standard with an average of 0.64mg/l.

Since then, the SPEL Stormceptor® Class 1 by-pass and the Puraceptor® Class 1 full retention Separators have advanced in performance and construction as a result of technological advances in design and manufacture.
The ‘heart’ of the SPEL Separators is the unique long life, low maintenance coalescer unit/s which ‘polishes’ the final effluent after 90% hydrocarbon and silt have been separated out.

Coalescer units comprise a stainless steel basket with a robust and efficient high volume reticulated foam insert. The coalescing process brings the smaller globules of oil into larger and more buoyant forms to separate by gravity. The high volume foam safeguards against blockages and ensures a long life between servicing.

The coalescer inserts are easy to clean and simple to replace but rarely require replacing. The unique ‘insert’ format ensures that this unit can be extracted complete every time, compared to other systems where ‘wrap around’ style units allow the foam to slip off, requiring confined space entry to retrieve.

How to Select and Specify SPEL Oil Separators

Selecting the appropriate type of SPEL Separator

Follow these steps to specify your requirements

Step 1
Determine the type of separator – full retention or by-pass – Class 1 or Class 2

Step 2
Size the unit to the contributing catchment area. This is the SPEL Separator Nominal Size (NS/NSB)

Step 3
Specify whether silt capacity is required integrally or via alternative upstream of the system. SPEL models with integral silt capacities have the “SC” suffix to model numbers

Step 4
Cross check the peak flow rate including “climate change” requirements – eg. return storm frequency and percentage for climate change

This flow chart is to aid selection of the most suitable and appropriate type of SPEL Separator for use in surface water drainage systems that discharge to surface water bodies such as rivers and soakways. However, the appropriate provision on any site will require detailed consideration of the local circumstance and risk factors including:

– The discharge point of your proposed separator
– The environmental sensitivity of your location
– Activities on your site
– Spill control (see APEA Blue Book)

Is there a risk of oil contaminating the drainage from the site?

Risk of infrequent light contamination and potential for small spills only.

e.g. car park

SPEL Stormceptor® by-pass separator with alarm required.

Class 1 if discharging to surface water

Class 2 if discharging to foul sewer

Risk of regular contamination of surface water run off with oil and/or risk of larger spills.

e.g. vehicle maintenance area, goods vehicle parking or vehicle manoeuvring

SPEL full retention separator with alarm required.

Class 1 if discharging to surface water

Class 2 if discharging to foul sewer

Drainage will also contain dissolved oils, detergents or degreasers such as vehicle wash water and trade effluents.

e.g. industrial sites

Trade effluents must be directed to the foul sewer.

It may need to pass through a SPEL Class 2 full retention separator before discharge to sewer to remove free oils.

Fuel oils are delivered to and dispensed on site.

e.g. industrial sites

SPEL full retention ‘forecourt’ separator with alarm required.

SPEL Puraceptor® class 1 forecourt separator FP1C (single chamber) or FP2C (two chamber) separator.

Class 1 if discharging to surface water

Class 2 if discharging to foul sewer

Very low risk of oil contamination.

e.g. roof water

Separator not required

Roof/clean water should not be passed through the separator unless the size of the unit is increased accordingly.