Effect of air pollution-controlled residue of a sewage sludge incinerator on the drying shrinkage and the pore structure of alkali-activated materials

Jiaxing Ban; Keke Sun; Jian-Xin Lu; Hafiz Asad Ali; Jun Yao; Geoffrey Sunahara; Chi-Sun Poon

doi:10.1016/j.wasman.2023.03.003

Effect of air pollution-controlled residue of a sewage sludge incinerator on the drying shrinkage and the pore structure of alkali-activated materials

Waste Manag. 2023 Apr 15:161:178-186. doi: 10.1016/j.wasman.2023.03.003. Epub 2023 Mar 6.

Authors

Jiaxing Ban¹, Keke Sun², Jian-Xin Lu³, Hafiz Asad Ali⁴, Jun Yao⁵, Geoffrey Sunahara⁶, Chi-Sun Poon⁷

Affiliations

¹ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, China; School of Water Resource and Environmental, Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), Beijing 100083, China. Electronic address: jiaxiban@polyu.edu.hk.
² Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, China. Electronic address: ke-ke.sun@polyu.edu.hk.
³ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, China. Electronic address: jianxin.lu@polyu.edu.hk.
⁴ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, China. Electronic address: hafiz-asad.ali@polyu.edu.hk.
⁵ School of Water Resource and Environmental, Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), Beijing 100083, China. Electronic address: yaojun@cugb.edu.cn.
⁶ School of Water Resource and Environmental, Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), Beijing 100083, China; Department of Natural Resource Sciences, McGill University, 21111 Lakeshore Drive, Ste-Anne-de-Bellevue, Quebec H9X 3V9, Canada. Electronic address: geoffrey.sunahara@mcgill.ca.
⁷ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, China. Electronic address: cecspoon@polyu.edu.hk.

PMID: 36889124
DOI: 10.1016/j.wasman.2023.03.003

Abstract

Recycling air pollution-controlled residues (APCR) generated from sewage sludge incinerators can be used for waste management, but the leaching of potentially toxic heavy metals from APCR poses environmental and human health issues. The present paper describes a procedure using APCR to produce alkali-activated materials and thereby realize their disposal. The effect of APCR on the compressive strength and drying shrinkage of the alkali-activated slag/glass powder was investigated. The pore structure characteristics were analyzed for clarifying its relationship with drying shrinkage. The results indicated that the drying shrinkage of the alkali-activated material was related to the mesopore volume. The drying shrinkage was slightly increased after the incorporation of the 10 % APCR, which was likely attributed to the high volume of mesopores compared to the 20 % APCR that lowered the drying shrinkage and compressive strength. This decrease in drying shrinkage was due to the recrystallization of sodium sulfate in the pore solution that can act as expansive agents and aggregates. The growth stress of the crystalline sodium sulfate within the matrix can offset the tension stress caused by the water loss. In addition, leaching studies using the SW-846 Method 1311 showed that recycling APCR into the alkali-activated system did not present a toxicity leaching risk or release unacceptable concentrations of heavy metals. The incorporation of waste APCR and waste glass can make AAMs a very promising and safe environmental technology.

Keywords: Alkali-activated reaction; Leaching; Volume stability; Waste glass powder; Waste management.

MeSH terms

Air Pollution* / analysis
Alkalies / analysis
Alkalies / chemistry
Humans
Metals, Heavy* / analysis
Sewage / chemistry

Substances

Sewage
sodium sulfate
Alkalies
Metals, Heavy