Application of Electro-coagulation Assisting the Fixed Carrier Biological System for Treatment of Bottom Ash Wastewater

• Main Authors: Ke-Ming Lai, 賴科名
• Other Authors: Cheng-Fang LIN
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/73895544453502951933

碩士 === 國立臺灣大學 === 環境工程學研究所 === 99 === Fixed Carrier Biological System in a single-pass process with long sludge retention time (SRT) and low solids production rate was developed and tested to achieve simultaneous removals of organic carbon and ammonia nitrogen with the assisting of electro-coagulation. This is because electro-coagulation (EC) has become an alternative application to replace chemical coagulation and effectively applied in industrial wastewater treatment because of EC can remove the suspended and colloidal solids, heavy metals and refractory substances in the wastewater. The influent of bottom ash wastewater consists 450-550 mg/L of SS, 370-420 mg/L of COD, 1.701-1.711 mg/L of heavy metals. The EC was compared with another two types of pretreatment methods, anion and cation polymers as pretreatment for FCBS. Under the experimental conditions, all the pretreatment methods able to remove up to 90% suspended solids, but anion and cation polymers were not effectively in removing the COD and heavy metals. The EC with optimum operating parameters (voltage-200 V, flow-500 mL/min) as the pre-treatment of the FCBS could remove 535 mg/L (97.3%) SS, 59 mg/L of COD (15.5%), 1.491 mg/L of heavy metals (87.44%). The effluent of EC was being fed to FCBS, and to help FCBS achieved excellent performance removal rate of SS (98.47%), COD (75.26%)and heavy metals (91.15%). Therefore, EC was selected as a better pretreatment consideration as compared with other pretreatment methods for FCBS in order to remove SS and heavy metals (copper) effectively. Further, it was found that the conductivity in the wastewater does not affect the removal rate for EC and the higher the voltage and the flow in the electro-coagulation, the higher the removal efficiency of the SS、COD、Cu and the pH is.