To Introduce & Optimize Suitable Biocide Program to Reuse Water in Paper Manufacturing Process

Security Paper is being manufactured in Paper Mill from cellulose fiber pulp. Water is being used in various stages of pulp & paper manufacturing processes. Security Pulp & Paper Mill (SPM) is having full flagged effluent treatment plant (ETP). Back water is being treated in effluent treatment plant. SPM has installed & commissioned a state-of-the-art Filtration plant for recycle & reuse of the treated water of ETP. The recycled water is being distributed through pipelines to various sections of the Paper Mill through overhead tank. SPM has faced some technical problems while utilizing the filtration plant recycled water in paper making process. There was microbial growth (slime & algae) observed in recycled water, as back water contains fines of cellulose fibers & residuals of other paper making additives and these are good sources of food for microorganism under favorable conditions of pH and temperature, these helps in generation of slime & algae in the water tanks, pipe lines and paper making process. We studied the problem & to eliminate the microbial growth, it was planned to add biocide dosage in recycled water system to avoid growth of slime & algae. By using biocide treatment, recycled water quality has been improved and it is being recycled for paper making process as well as for the horticulture purpose.