Technique for Advanced Electrochemical Oxidation Treatment of Nanofiltration Concentrate of Landfill Leachate

• Published in: Wuhan University journal of natural sciences Vol. 19; no. 4; pp. 355 - 360
• Main Authors: Xiong, Changgui, Li, Guang, Zhang, Zhiliang, Xia, Zhengwu, Li, Jian, Ye, Hongji
• Format: Journal Article
• Language: English
• Published: Wuhan Wuhan University 01-08-2014
• Subjects: Biomedical and Life Sciences; Computer Science; Current density; Electrochemical oxidation; Electrodes; Landfills; Life Sciences; Materials Science; Nanofiltration; Oxidation; Pollutants; China, People's Rep., Hubei Prov., Wuhan; electrode; electrochemistry; nanofiltration concentrate of landfill leachate; pulse; X703.1; pollutants; advanced oxidation
• ISSN: 1007-1202; 1993-4998
• DOI: 10.1007/s11859-014-1025-1

Landfill leachate treated with combined process of ＂pretreatment ＋biological treatment ＋advanced treatment （NF）＂ to produce nanofiltration concentrate, which bio-chemical ratio （B/C） is less than 0.1 and CODer concentration is 2 000-2 500 mg/L, high salt content. Which cannot be discharged under existing environ- mental standards. According to analysis based on electrochemical advanced oxidation mechanism, a two-step electrochemical tech- nique was recommended. In the first step, a pulse electrochemical technique was adopted. With Fe as consumption electrode and current density of 10 mA/cm2, the pollutants were removed by means of Fenton reaction, electroflotation and electrocoagulation. In the second step, a double function electrode was used to per- form electrocatalytic oxidation by means of titanium metallic oxi- dates. In the condition that current density being 12.5 mA/cm2, the pollutants were further removed by oxidation and electrolytic deposition. Result shows that the removing rate of CODer, NH3-N and CI were 70%-85%, 90% and 25%, respectively; average value of B/C ratio increased from 0.09 to 0.38 and conductivity reduced by 10%.