Combination of FeGAC/H2O2 advanced oxidation process and sequencing batch reactor for treatment pesticide wastewater

Abstract

The combination of granular activated carbon (GAC)–hydrogen peroxide (FeGAC/H2O2) (pretreatment phase) and sequencing batch reactor (SBR) (post-treatment phase) for the removal of biochemical oxygen demand, chemical oxygen demand and improvement of the biodegradability of the pesticide wastewater was studied. In the pretreatment phase, COD and TOC removal were 64.2 and 50.5 %, respectively, and biodegradability (BOD5/COD ratio) increased from 0.02 to 0.34. During the SBR, initial treatment of the pretreated wastewater without addition of municipal wastewater was not sustained. The pretreatment time was further increased before combining the wastewater with municipal treatment plant wastewater for an effective treatment. The FeGAC/H2O2-SBR reached 97.1, 98.0 and 99.9 % for COD, TOC and BOD5 removal, respectively. The FeGAC/H2O2-SBR process can be applied for the treatment of pesticide wastewater to meet the Malaysian regulatory effluent discharge standard.