| Water use reduction and effluent reduction in pulp and paper mills have become a very hot topic in North America during the past several years. This trend has had a much longer history in the European pulp and paper community where most of the research has been performed.; This study examines the current bleach plant at Fraser Papers Inc., Edmundston Operations, in an attempt to help reduce the quantity of the overall mill effluent, which currently approaches the government set limits.; Simulation of the bleach plant was performed using WinGEMS 4.0, with the objective to quantify all the fresh water usage and sewered streams, and to predict the effect of process changes on the entire system. It was found that the bleach plant uses approximately 12,200 m3/day or 3.22 million usgpd fresh water, mostly for shower water on the washers. It was also found that the sewer flow rate can vary from about 28,000 m3/day or 7.39 million usgpd to 40,000 m3/day or 10.6 million usgpd.; The study shows that there are many opportunities to significantly reduce the bleach plant effluent flow without major capital expenditure by reuse of filtered white water as shower water, wire cleaning shower water and dilution water. |
