Change in re-use value of incinerated sewage sludge ash due to chemical extraction of phosphorus

Jiang-Shan Li; Zhen Chen; Qi-Ming Wang; Le Fang; Qiang Xue; C R Cheeseman; Shane Donatello; Lei Liu; Chi Sun Poon

doi:10.1016/j.wasman.2018.01.007

Change in re-use value of incinerated sewage sludge ash due to chemical extraction of phosphorus

Waste Manag. 2018 Apr:74:404-412. doi: 10.1016/j.wasman.2018.01.007. Epub 2018 Jan 5.

Authors

Jiang-Shan Li¹, Zhen Chen², Qi-Ming Wang², Le Fang², Qiang Xue³, C R Cheeseman⁴, Shane Donatello⁵, Lei Liu³, Chi Sun Poon⁶

Affiliations

¹ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong; State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China.
² Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
³ State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China.
⁴ Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom.
⁵ Cements and Materials Recycling Department, Eduardo Torroja Institute of Construction Sciences, Consejo Superior de Investigaciones Cientificas (CSIC), c/ Serrano Galvache, 4, Madrid, Spain.
⁶ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong. Electronic address: cecspoon@polyu.edu.hk.

PMID: 29311013
DOI: 10.1016/j.wasman.2018.01.007

Abstract

The potential of six different extractants to recover phosphorus (P) from incinerated sewage sludge ash (ISSA) was evaluated. Secondary effects such as the co-dissolution of Zn and Cu were also considered. The residual ISSA from each study was assessed in particular detail, focusing on the leachability of remaining Zn and Cu, major element composition, crystalline phases and overall degree of crystallinity and particle size distribution. The residual ISSA was also evaluated as a pozzolanic material using a Strength Activity Index (SAI) test with mortars containing Portland cement with a 20% substitution by ISSA. All results were compared to tests with untreated ISSA. Overall, the use of 3 of the 6 extractants could be ruled out due to poor P recovery potential and/or a serious compromise of the potential reuse of residual ISSA in Portland cement-based materials. The results highlight the added value of considering the potential reuse of residual ISSA when trying to optimize P recovery from ISSA by wet methods.

Keywords: Characterization; Chemical extraction; Heavy metals; Incinerated sewage sludge ash; Phosphorus; Pozzolanic activity.

MeSH terms

Construction Materials*
Incineration
Phosphorus / chemistry*
Sewage / chemistry*

Substances

Sewage
Phosphorus