Evaluation of boron removal by coagulation process

Automobile industry specifically vehicle washing activities use voluminous drinkable water into wastewater contributes to the risk of global water scarcity. In the treatment of vehicle washing wastewater, coagulation process is widely applied due to its effectiveness and relatively simple operation in comparison to alternative methods such as adsorption. However, in literature review, very few studies compare the effectiveness of natural and pre-hydrolysed coagulants against conventional coagulants to assess the pollutant removal from automobile industry wastewater. Direct comparison of data with the use of different coagulants are difficult with current available research due to inconsistencies of data. Therefore, the purpose of this research aims to evaluate removal of Chemical Oxygen Demand (COD), turbidity and Total Suspended Solids (TSS) from automobile industry wastewater with the use of chitosan, alginate, aluminium sulphate (alum), ferric chloride (FeCl3), polyaluminium chloride (PAC), aluminium chlorohydrate (ACH) and polyferric sulfate (PFS) under acidic, neutral, and alkaline condition to compare natural coagulants and synthetic chemical coagulants with jar test. It this study, it was found that chitosan, ACH, and PFS has effective COD removal of up to 98 % regardless of the pH change. Complete TSS removal was found by using chitosan, ACH, and PFS at pH 5. At pH 5, turbidity removal of chitosan, ACH, and PFS were obtained as 84.26 %, 96.79 % and 99.89 %. Therefore, the performance of chitosan, ACH, and PFS are comparable to alum and hence, have potential as alternative coagulants in treating automobile industry wastewater.