Retention Aids and Deaerators in the Prodution of Wood-containing Printing Papers, 1999 Papermakers Conference Proceedings

Werner J. Auhorn

Developments in papermaking technology over the past forty years led to the fact that retention aids and deaerators are indispensable in the production of virtually all grades of paper. This is because of the beneficial effect they have on economics and ecology of the papermaking process and the quality of the paper produced. In case of the wood-containing printing papers referred to here, retention aids and deaerators have both played an important part in achieving high production rates and making it possible for large proportions of deinked pulp and fillers to be used. They have also been instrumental in reducing fresh water consumption and the amount of effluent generated per tonne of paper produced. They have enabled basis weights to be reduced, and they have contributed to the large net increase in productivity relative to the width of the paper machine.

In view of the great progress that has been made, it is surprising that the proportion of the total consumption of process chemicals accounted for by products such as retention aids, fixing agents, flocculants, deaerators and defoamers is not much higher than it is. Retention aids, fixing agents and flocculants account for only 5 % of consumption and deaerators and defoamers for only 1 %.