TG- MS study on in-situ sulfur retention during the co-combustion of reclaimed asphalt binder and wood sawdust

Teng Wang; Hao Rong; Si Chen; Yi Zhou; Jinping Li; Yue Xiao; Yongjie Xue

doi:10.1016/j.jhazmat.2020.123911

TG- MS study on in-situ sulfur retention during the co-combustion of reclaimed asphalt binder and wood sawdust

J Hazard Mater. 2021 Feb 5:403:123911. doi: 10.1016/j.jhazmat.2020.123911. Epub 2020 Sep 19.

Authors

Teng Wang¹, Hao Rong², Si Chen¹, Yi Zhou³, Jinping Li¹, Yue Xiao³, Yongjie Xue⁴

Affiliations

¹ School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan 430073, China.
² Changjiang Institute of Survey, Planning, Design and Research, 430014, Hubei, Wuhan, China.
³ State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China.
⁴ State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China. Electronic address: xyjskl@whut.edu.cn.

PMID: 33264964
DOI: 10.1016/j.jhazmat.2020.123911

Abstract

Reclaimed asphalt binder (RAB) releases large amounts ·of hazardous sulfur-containing gases during combustion. This study attempts to introduce wood sawdust (WS) as an in-situ inhibitor of sulfur release during the combustion of refuse-derived fuel (RDF) blended with RAB-WS. The combustion characteristics, gaseous sulfur-containing products, interactions and combustion kinetics of RDF were investigated through thermogravimetry and mass spectrometry (TG-MS), and the mechanisms on migration and distribution of sulfur were revealed. Results indicated that WS additive inhibits the volatilization of light components and promotes the degradation of macromolecular components. WS addition improved the combustibility, burnout performance and combustion stability of RAB. The sulfur release of RAB-based RDF was mainly derived from resins and asphaltenes. WS addition generally decreased all gaseous sulfur-containing compounds (CH₃SH, COS, SO₂, CS₂ and thiophene). Interactions between RAB and WS restrained all sulfur-containing gas emissions, and the normalized sulfur inhibition ratio reached 40.99 %. The Sarink and DAEM models could well describe the kinetic process of the co-combustion of RAB and WS. WS addition led to a decrease in activation energy, namely, it lowered the reaction barrier. Sulfur could be retained in-situ into incineration residue through the formation of sulfate minerals during the co-combustion of RAB and WS.

Keywords: Co-combustion; Reclaimed asphalt binder; TG-MS; Wood sawdust; sulfur retention.

Publication types

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