Chipboard glue from cradle to grave

Anne Berit Bjørken

Relative contributions made by production of urea, methanol, formaldehyde and UF glue to the total environmental load.

The analysis was carried out by Egil Ophus, senior lecturer in NTH's Dept. of Industrial Management and Work Science (ORAL), in collaboration with Dyno and the Research Council of Norway.

Methanol and urea are the raw materials for the urea-formaldehyde glue which is produced by Dyno in Lillestrøm and used in the manufacture of chipboard. Both methanol and urea are imported from The Netherlands. Methanol is produced from natural gas, releasing CO2. The life-cycle analysis shows that the amount of CO2 released in the course of producing sufficient methanol for one ton of glue is equivalent to the emissions from a petrol-driven private car driving 1,000 km. One ton of glue is sufficient for 10 cubic metres of chipboard.

"It is quite impossible to say whether this is a serious or a minor environmental load. Our evaluation is that total emissions from Dyno's glue manufacturing line are low, and that the most serious environmental emissions take place during the raw-materials phase," says Ophus.

The glue analysis includes data on releases of CO2, ammonia, NOx, sulphur dioxide, urea dust, formaldehyde and other waste products from all stages of the life- cycle. At the same time, data on energy consumption during all the phases of glue production are gathered. According to the researchers, emissions to the atmosphere from glue production result in only minor loads on the environment.

"Even if the environmental loads are low, we have found it possible to recommend a number of improvements which would reduce emissions of formaldehyde and possibly also of methanol during the process of manufacturing UF glue. The analysis has shown that a transfer to new technology at certain stages of production would improve the work environment, for example by reducing exposure to formaldehyde," says Ophus.

Releases to water are insignificant. The environmental loads due to the manufacture and use of chipboard are directly related to the amount of free formaldehyde in the glue and the boards themselves.

"Current environmental regulations are being satisfied, but improvements in the product are still desirable," says Ophus, who emphasizes that the amount of formaldehyde used in chipboard has fallen dramatically in the course of the past 20 years.

Even though it is the raw materials stage that offers the most important environmental challenge, the analysis has also identified a number of improvements that could be made at Dyno's Lillestrøm plants.

Participation in this project has given NTH expertise in dealing with life-cycle analyses which it will be able to use in its teaching on environmental subjects.

Life-cycle analyses of the environmental effects of products is a methodology in rapid development. A life-cycle analysis is an environmental assessment of a product "from cradle to grave," i.e. from extraction of its raw materials, manufacturing, distribution, use, and possible re-use, until it becomes waste.