Salinity Reduction of Borneo Tropical Brackish Peat Water with Electrocoagulation Treatment

• Main Author: Calvin, Jose Jol
• Format: Thesis
• Language: English; English
• Published: Universiti Malaysia Sarawak 2023
• Subjects: T Technology (General); TP Chemical technology
• Online Access: http://ir.unimas.my/id/eprint/42035/1/Calvin%20Jose%20Jol%20-%20%20Master%20Thesis%202023%20-%20Chemical%20Engineering.pdf; http://ir.unimas.my/id/eprint/42035/3/Declaration%20Form%20-%20Calvin%20Jose%20Jol.pdf; http://ir.unimas.my/id/eprint/42035/
• Institution: Universiti Malaysia Sarawak

Sarawak located on Borneo Island has vast availability of brackish peat water sources especially in some coastal rural areas. However, brackish peat water is currently underutilized as the source for water treatment plants in the state due to excessive salinity levels. As such, this study aims to investigate the salinity reduction in brackish peat water sources for domestic consumption in Sarawak coastal rural areas by utilizing continuous electrocoagulation treatment with aluminium electrodes. Correspondingly, this study analyzes the effects of seawater percentage, electric current, and flow rate on salinity reduction with electrocoagulation treatment. This study has found that the treated salinity levels in brackish peat water with 30% of seawater percentage meet the Malaysia Class I standard in National Water Quality Standard. The study has also identified both monolayer and multilayer adsorption that occur in electrocoagulation treatment as the precursor to salinity reduction. In addition, the presence of in-situ aluminium hydroxides coagulants could adsorb some sodium chloride from brackish peat water with 70% of seawater percentage at 2,503 mg/g of maximum adsorption capacity and 2.65 min-1 of adsorption rate. From the statistical analysis conducted, this study found that electrocoagulation treatment could achieve 91.78% of maximum salinity reduction efficiency with an optimum electric current of 5 A and flow rate of 1.2 L/min in brackish peat water with a 30% of seawater percentage. This treatment system costs only RM 0.29 per meter cubic of treated brackish peat water at optimum conditions. Overall, this study demonstrates that continuous electrocoagulation treatment could reduce the salinity levels in brackish peat water with 30% of seawater percentage which is considered safe for domestic consumption in Sarawak coastal rural areas at reasonable cost. Keywords: Brackish peat water, electrocoagulation, salinity reduction, adsorption