3. FOAM PRODUCTION

Eliminating ozone depleting and global warming substances from foam production is of paramount importance, given the large volumes of chemicals involved. The global CFC consumption in the foam sector in 1990 was 174,000 metric tonnes. The global usage of CFCs in appliance foams in 1990 was 38,000 metric tonnes [approximately 21 percent of the total CFC used in the foam sector]. * In 1991, the Technology and Economic Assessment Panel of the Montreal Protocol, estimated that "...150,000 tonnes of HCFCs a year would be required to achieve a CFC phase out in foam plastics in the developed countries in 1995". **

3.1 Building insulation

Rigid Polyurethane foam (PUR) is commonly used in construction as an insulating foam. There are a number of different kinds of foam which are all rigid PUR - most noteably, boardstock, sandwich panels and spray foams .

Boardstock is prominently used in roof and wall insulation in commercial buildings. Sandwich panels, where the foam is sandwiched between facing materials such as steel and aluminium, are used for insulating cold stores, cold rooms and doors. Spray foams are made at the point of use and are literally sprayed into place. They are highly suitable for the insulation of uneven or inaccessible surfaces and are used in storage tanks, pipe work and refrigerated trailers.

Particularly in Europe (see case study), companies are using pentane - a hydrocarbon - as an alternative blowing agent for both board stock and sandwich panels. Thanex in Denmark have used a mechanical process for producing PUR insulating foam. Recticel (Belgium), the largest manufacturer of PUR foams in Europe, and Bayer, have been producing hydrocarbon blown foams for construction applications for a number of years.

Alternatively, CO2 is currently being used as the blowing agent by ICI and Liquid Polymers Group in the UK, ResinaChemie and BASF in Germany and Nassau Doors in Denmark. Carbon dioxide blowing, in combination with process changes, as demonstrated by Windsor Doors in Norway, is a proven technology for spray foams.

Often the best alternatives to polyurethane boardstock are not foam at all. Magnesium carbonate, as produced by Darchem in the UK, can be made into an insulation product for use in power stations and oil installations. Products such as mineral fibre and fibreboard have always been in competition with polyurethane. Mineral fibre is dominant in insulation products in the UK. Meanwhile, the Swiss company Isofloc produces boardstock panels made out of cellulose. The panels are made out of recycled materials.

Extruded polystyrene is also used as a rigid boardstock, where its moisture resistance and strength make it suitable for below ground construction insulation , for example, in foundations. Dow Chemicals and BASF use carbon dioxide technology to produce extruded polystyrene. The product is sold in many European countries.

* UNEP, "Elimination of CFCs from Domestic Refrigeration Manufacture": Information Paper, OzonAction Information Clearinghouse, OzonAction Programme, July 1994: Section 2.2.1, p.2 [return]

** TEAP Report 1991: Montreal Protocol On Substances that Deplete the Ozone Layer: "1991 Assessment: Report of the Technology and Economic Assessment Panel (TEAP)", December, 1991: Section 8, p.11 [return]