BP bags petrol to curb VOC emissions
A collapsible bag storage system to minimise the build-up of volatile organic compounds (VOC) in the void space of fixed fuel tanks is being developed by BP Oil. The new technology may reduce the costs of controlling VOC emissions.
Petrol distribution accounts for an estimated 127,000 tonnes of VOC emissions each year in the UK (ENDS Report 202, p 6). EC legislation to curb these releases is at an advanced stage of preparation (ENDS Report 202, pp 38-9).
Normally, vapour recovery units incorporating activated carbon are used to abate VOCs. BP's technology may stop the VOCs from being produced in the first place.
The concept is simple. A collapsible bag is installed inside road and underground storage tankers. Petrol is kept inside the bag, which expands and contracts as fuel is added or removed.
About 0.5% of fuel product is lost in distribution. The bag system "will be able to reduce this figure to a small fraction - at a fraction of the costs of vapour recovery units," according to David Rulison, Technical Development Manager at BP. How much less is not yet known.
BP still needs to overcome several problems. First, a collapsible hose has to be developed to exclude air from being pumped into the bags. Secondly, a non-permeable, strong material that collapses in the right way has to be found.
BP hopes to have a road tanker trial under way by July and another, on a pilot retail tank, in October. More extensive trials are planned for 1993. But the bags are unlikely to be commercialised on a large scale for 5-15 years, David Rulison believes. Meanwhile, BP will need to install vapour recovery units to comply with new legislation on VOCs.