Integration of hydrothermal and pyrolysis for oily sludge treatment: A novel collaborative process

Yihang Duan; Ningbo Gao; Cui Quan

doi:10.1016/j.jhazmat.2023.131005

Integration of hydrothermal and pyrolysis for oily sludge treatment: A novel collaborative process

J Hazard Mater. 2023 May 5:449:131005. doi: 10.1016/j.jhazmat.2023.131005. Epub 2023 Feb 14.

Authors

Yihang Duan¹, Ningbo Gao², Cui Quan¹

Affiliations

¹ Xi'an Key Laboratory of Solid Waste Recycling and Resource, Recovery, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
² Xi'an Key Laboratory of Solid Waste Recycling and Resource, Recovery, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China. Electronic address: nbogao@xjtu.edu.cn.

PMID: 36801709
DOI: 10.1016/j.jhazmat.2023.131005

Abstract

In this study, hydrothermal treatment and in situ pyrolysis were combined to develop a novel collaborative process (HCP treatment method). In a self-designed reactor, the HCP method was used to study the influences of hydrothermal temperature and pyrolysis temperature on the product distribution of OS. The products from the HCP treatment of OS were compared with that from the traditional pyrolysis. In addition, the energy balance in the different processes of treatment was analyzed. The results showed that compared to the traditional pyrolysis method, the gas products obtained after HCP treatment achieve a higher H₂ production. As the hydrothermal temperature raising from 160 to 200 °C, the H₂ production showed an increase from 4.14 to 9.83 ml/g. In addition, GC-MS analysis showed that the content of olefins from the HCP treatment oil was increased from 1.92% to 6.01% compared to traditional pyrolysis. Energy consumption analysis showed that only 55.39% energy consumption of traditional pyrolysis is required for treating 1 kg OS by employing the HCP treatment at 500 °C. All results indicated that the HCP treatment is a clean production process of OS with low energy consumption.

Keywords: Energy consumption; H(2) yield; Hydrothermal; Oily sludge; Pyrolysis.