EFFLUENT TREATMENT IN THE FINNISH PULP AND PAPER-INDUSTRY - PRESENT STATE AND FUTURE-PROSPECTS

In Finland, the regulation of effluent loadings is based on discharge permits and Water Rights Court procedures, both of which differ from the practice in most other countries. This is because most waters in Finland are in private hands. The recommendations given for the regulation of discharges, which are based partly on technological progress and partly on the results of international cooperation, will probably acquire greater significance, both in Finland and elsewhere. Reducing effluent loadings goes hand in hand with measurement methods developed for this purpose, i.e. with the effluent parameters. However, in Finland, the suitability of the parameters currently used for pulp and paper mill effluents is questionable. The present situation is holding back progress, particularly in regard to effluent treatment processes. Most of Finland's activated sludge plants were built during the 1980s. Although plenty of mistakes were made, most of there have now been put right. At the same time, much useful information has been gained for both process design and treatment plant control. One of the biggest challenges in the near future is likely to be minimizing phosphorus discharges from chemical pulp mills prompted mainly by the need to bring down high spot loadings. The rapid progress being made in chemical pulping will bring not merely benefits but possibly also the need to further develop effluent treatment processes.