Stripper stamps out the stink

That 'new smell' - the one that hits you when you step into a brand new car - is on the way out, thanks to a process developed by Shell.

Polyol chemicals are used widely to create flexible polyurethane foams for the polyurethane furnishing and automotive seating markets. However, foams made from polyols can emit very small amounts of harmless volatile organic compounds (VOCs) if they are not properly prepared and stored prior to conversion into the final article.

It's these VOCs in polyol that are, in part, responsible for odour in a new car or sofa. As well as causing potential odours in furnishing industry products, it is thought that polyol-based products used in car interior products are also a contributing factor in causing 'fogging' - a small build-up of condensation on the inside of windscreens.

Polyols themselves are produced via the reaction of glycerine with propylene oxide and ethylene oxide in the presence of a catalyst. VOCs are formed as by-products during the course of the reaction.

To address the issue, polyols producers and the European flexible foam manufacturers industry group, EUROPUR, launched an initiative to find ways of reducing residual foam odours.

Three years ago, Shell chemicals companies also launched their own 'VOC and odour lean' plan. Initially, several steps were taken in the polyol production process to suppress odour. However, this did not totally eliminate the issue.

Last year, however, a team at the Shell Pernis plant in the Netherlands set out to design a piece of equipment that strips out the VOCs from the polyols process. This column takes the polyols at the top end and, in a vacuum, a stripping agent is blown through it.

According to Pieter Oldenhove, a process technician at the Pernis polyols plant: 'The odour stripper has proven to be very successful and is the culmination of our three year 'odour lean' programme. One of the important things is that it is able to do the job without impacting production capacity.'

The technology has also been 'exported' to the Shell polyols plant in Singapore. A similar piece of equipment has been installed in the Seraya complex there, and will also be incorporated in the new extension of the plant due to come on-stream in April this year.