German conference hears conflicting views on whether plastic fuel tanks can meet Californian emission standards

German conference hears conflicting views on whether plastic fuel tanks can meet Californian emission standards

Plastic fuel tanks may not meet Californian emission standards, a conference in Germany heard last week. Director of engineering fuels systems at Tesma Dr Gьnther Pozgainer told the Tank Tech 2003 conference that the PZEV (Partial Zero Emission Vehicle) standard can only be achieved with metal tanks at present. His research calculated the level of emissions from systems using metal tanks and a variety of plastic tanks.

However, other speakers maintained that plastic could meet the targets. Dr Pierre Delbarre, global director of materials and innovations at TI Automotive, said its Permblok AS6 system did comply. The system uses both EVOH and Atofina Orgalloy FT104 PA/PO blend as barrier materials. The Orgalloy welds to itself at the pinch-off of co-extruded blow moulded tanks to eliminate the permeation window in the pinch-off area that occurs when only an EVOH barrier is used.

Delbarre stressed that the PZEV emission limits could only be met with the Permblok AS6 solution when it is combined with TI Automotive’s SIB (ship in a bottle) system; this involves additional sealing of components within the tank. Inergy Automotive Systems representatives told PRW.com the company had plastic tank solutions to comply with PZEV involving additional welded plastic protection over the tank.

The PZEV emission limits of 0.35g per test and 0.054g per fuel system are due to come into force in California from 2005.