Bioremediation of Paper Mill Effluent using Bacillus subtilis and Escherichia coli

Abstract

Effluent from onward paper mill limited Nigeria was collected and analyzed. Bacillus subtilis, Escherichia coli and mixed cultures of both organisms were used to bioremediate the effluent collected. The setups were inoculated with Bacillus subtilis, Escherichia coli and mixed cultures of these two organisms, respectively. Setup of E was inoculated and used as a control. Physicochemical and microbiological analyses were carried out for 12weeks to check the effectiveness of the organisms in carrying out the bioremediation process. The nitrate, phosphate and sulphate levels showed a reduction throughout this experiment. The pH ranged from 6.4-7.6. The BOD levels decreased in all setups, indicating microbial activities from 120mg /L - 92 mg /L in setup A. The mean population density of all the microorganisms for culture development also increased. It increased from 2.3x103 - 3.5x103 for Bacillus subtilis. This shows microbial growth and multiplication. Also, the dissolved oxygen level increased from 3.8mg /L - 4.7mg /L in setup D. The experiment indicates that the inoculated organisms carried out a certain degree of bioremediation.