Feasibility of bioleaching combined with Fenton oxidation to improve sewage sludge dewaterability

Changgeng Liu; Panyue Zhang; Chenghua Zeng; Guangming Zeng; Guoyin Xu; Yi Huang

doi:10.1016/j.jes.2014.05.039

Feasibility of bioleaching combined with Fenton oxidation to improve sewage sludge dewaterability

J Environ Sci (China). 2015 Feb 1:28:37-42. doi: 10.1016/j.jes.2014.05.039. Epub 2014 Nov 15.

Authors

Changgeng Liu¹, Panyue Zhang², Chenghua Zeng³, Guangming Zeng⁴, Guoyin Xu⁵, Yi Huang⁵

Affiliations

¹ School of Resources and Environmental Engineering, Panzhihua University, Panzhihua 617000, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, China. Electronic address: changwyx@163.com.
² Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, China. Electronic address: zhangpanyue@hnu.edu.cn.
³ School of Resources and Environmental Engineering, Panzhihua University, Panzhihua 617000, China. Electronic address: zch1963111@sina.com.
⁴ Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
⁵ School of Resources and Environmental Engineering, Panzhihua University, Panzhihua 617000, China.

PMID: 25662236
DOI: 10.1016/j.jes.2014.05.039

Abstract

A novel joint method of bioleaching with Fenton oxidation was applied to condition sewage sludge. The specific resistance to filtration (SRF) and moisture of sludge cake (MSC) were adopted to evaluate the improvement of sludge dewaterability. After 2-day bioleaching, the sludge pH dropped to about 2.5 which satisfied the acidic condition for Fenton oxidation. Meanwhile, the SRF declined from 6.45×10(10) to 2.07×10(10) s2/g, and MSC decreased from 91.42% to 87.66%. The bioleached sludge was further conditioned with Fenton oxidation. From an economical point of view, the optimal dosages of H2O2 and Fe2+ were 0.12 and 0.036 mol/L, respectively, and the optimal reaction time was 60 min. Under optimal conditions, SRF, volatile solids reduction, and MSC were 3.43×10(8) s2/g, 36.93%, and 79.58%, respectively. The stability and settleability of sewage sludge were both improved significantly. Besides, the results indicated that bioleaching-Fenton oxidation was more efficient in dewatering the sewage sludge than traditional Fenton oxidation. The sludge conditioning mechanisms by bioleaching-Fenton oxidation might mainly include the flocculation effects and the releases of extracellular polymeric substances-bound water and intercellular water.

Keywords: Bioleaching; Dewaterabilty; Fenton oxidation; Sewage sludge.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Desiccation
Filtration
Hydrogen Peroxide / chemistry*
Iron / chemistry*
Oxidation-Reduction
Sewage / chemistry*
Waste Disposal, Fluid / methods*

Substances

Fenton's reagent
Sewage
Hydrogen Peroxide
Iron