Read the story of Abfad’s double-skin linings, which protect tanks from corrosion and offer integrity monitoring
In 2021, Abfad celebrated 25 years of providing access and corrosion prevention and monitoring solutions to the oil and gas and power generation industries. Their award winning Fuelvac double skin lining system has undergone several design and development changes over this time and continues to provide an answer to the protection and monitoring of above- and underground storage tanks.
THE CREATION OF ABFAD
Abfad was formed in 1996 by directors Alan Fada and Chris Haritou, with the vision of providing high quality trade experienced industrial coating rope access personnel, which was eventually extended to provide other trade services for construction and maintenance. A high level of specialist coating knowledge existed within the business which led the company to develop the award winning Fuelvac double skin tank lining system.
Abfad started out with five personnel, an old van and two bags of rope access equipment as a specialist abseiling coating company in 1996. Both directors had experience working in the industry offshore and onshore in the UK and Europe and Abfad quickly established synergy within shipyards providing specialist coating skills whilst working at height, without the need for scaffolding, platforms, or cradles.
SOLVENT-FREE TANK
LINING SPECIALISTS
In the early 2000s Abfad was approached by several large oil and gas companies to provide long lasting solvent-free coating protection for their underground storage tanks in the UK.
In 2002 BP requested refurbishment of their fuel forecourt underground storage tanks nationally within the UK. Abfad had four lining teams with plant and equipment set up to refurbish several of BP’s network of tanks throughout the UK.
The coating services provided by Abfad went well and BP requested that they supply a double skin liner for existing single wall steel and fibreglass storage tanks. This would need to be monitored using vacuum pressure transducer valves to comply with UK legislation passed in 1990.
Double skin liners are usually installed in storage tanks that cannot be removed from the ground or replaced with new constructed steel or fibreglass tanks. This can be for various reasons such as their location, they may be in busy built-up areas or where there are existing tunnels or waterways located, or in other locations where planning permission would not be granted. Cost is also a deciding factor for operators as installing a double skin lining system is a cheaper solution than storage tank replacement.
From this Fuelvac was created.
FUELVAC DOUBLE
SKIN LINING SYSTEM
Fuelvac is Abfad’s innovative double skin lining system and uses non-toxic, environmentally friendly materials including solvent free coating for final protection of stored cargo.
Fuelvac complies with COMAH regulations which set down rules for the prevention of major accidents involving dangerous substances, and to seek to limit the consequences for human health and environmental incidents. Fuelvac is certified to the European Standard
BS EN 13160-7 and has been successfully operating in above and underground storage tanks since 2007.
Where other double skin lining systems in the world use glass-reinforced plastic (GRP) or solvented resins which are hazardous for applicators and environment, Fuelvac is completely solvent-free and non-hazardous. The existing GRP systems on the market tend to be wet lay-up systems, meaning that the double skin layers are inserted into wet glass reinforced plastic resin. Fumes from this process cause damage to applicators, the public and the environment and are present throughout the whole process, which can last weeks or months as the resins are used daily.
Fuelvac is a sprayed solvent-free epoxy coating system. When coating a storage tank with a solvent-free, high solid epoxy resin a greater level of thickness can be achieved per application cycle. For this reason, these are typically one coat systems. Being able to apply the coating in a single application to achieve the required film thickness is a huge time saver and provides the best opportunity for long-term storage tank protection for operators.
With the correct preparation, solvent-free epoxies have excellent adhesion to the steel and will dry to form a hard tile-like finish. This gives the storage tank a ‘second skin’ which is resistant to sulphate-reducing bacteria corrosion, extending the service life of the tank. Solvent-free epoxies meet all the performance criteria of traditional solvent-based coatings, but in a more environmentally friendly way with the added benefit of long-term protection for steel and concrete.
WHAT DOES FUELVAC DO?
Fuelvac double skin tank liner prevents corrosion from impacting on the steel of the storage tank, whilst at the same time providing a safety net if there is ever a breach, so stored product will remain safely contained.
Fuelvac is a fully monitored system, containing an interstice (space) between the two layers of protective solvent-free resin, through which a vacuum is pulled and held. This vacuum alerts the client if a breach occurs, either internally or externally, as any breach to the tank would cause a drop in the vacuum which in turn would cause the system to alarm.
The Fuelvac system can be installed in both above and below ground tanks of any size and enables the safe and successful storage of hazardous liquids including crude oil, petroleum products and ethanol.
THE DEVELOPMENT OF
FUELVAC OVER THE YEARS
Over the years Fuelvac has consistently been developed and improved upon. The first double skin liners which would later become the Fuelvac system used a solvent-free epoxy coating for the protection of the tank steel, then once the coating was applied, a series of plastic sheets were fixed to the wall, floor and roof areas of the tank with hot melt adhesive. The idea was to create a tank within a tank and enable a space for monitoring between the original steel wall and the new plastic sheeting.
The second version of the double skin lining system used similar plastic sheeting as the first system but the initial solvent-free coating onto the steel was changed to be a solvent-free polyurethane paint. This system was installed in several sites for Network Rail throughout the UK.
After this the system was further developed to use polyvinylidene fluoride (PVDF), which is a chemical-resistant plastic ideally suited for the oil and gas industry. The coating used for this system was changed back to an epoxy solvent-free coating due to the changes in fuel additives and the start of biofuels. This system was used by Total UK in 2005 and installed in multiple sites across the UK.
The fourth and current version of the Fuelvac system solved the problems
with the speed at which the system could be installed.
Although all the previous versions of the lining system were successful, due to the unknown condition of the steel (which was often buckled and dented and could not be seen until the storage tanks were emptied, degassed, and cleaned) it was difficult to install plastic sheeting and Abfad wanted to reduce the amount of time it took to install over the defects within the tank steel. It was determined that a coating system with layers of materials which were non-hazardous to install and could create a monitoring space was needed.
This system took until 2007 to develop where it was installed for BP, Total and many other companies in the oil and gas industry. The monitoring space for this system is 1 mm as opposed to the 10 mm of space that was used in the first system. The space depth for monitoring the tank is important as it reduces the amount of stored fuel within the storage tanks which can be sold.
The monitoring space needs to be created from a material that maintains an open flow of air or liquid, even when compressed by the weight of the stored product. This is important as any compression of the interstitial space will mean parts of the storage tank are not monitored by the vacuum pressure. Therefore, the space created between the original steel wall and the double skin liner will not be able to provide an alarm should a breach occur in the sections which have been compressed.
Many types of materials were researched along with the thickness of the material layers for this system. The adhesion of the solvent free epoxy coatings to the materials and the ability to create strength within the liner were key factors in its development.
This current version of the Fuelvac double skin lining system has been successfully installed and is operating in over 180 storage tanks in the UK.
ACCREDITATIONS AND AWARDS
A milestone for Fuelvac and Abfad was reached in April 2018 as Fuelvac was accredited by TUV NORD to the European Double Skin Storage Tank Lining Standard BS EN 13160-7. Abfad believe Fuelvac is the only accredited solvent free double skin lining system in the world.
So successful was the development and advancement of Fuelvac that in 2019 it won first place in the Advanced Manufacturing category at the North East Innovation Awards in the UK against some stiff competition in a packed category of innovative companies.
For more information:
www.abfad.co.uk
