Modification of hydrochar increased the capacity to promote anaerobic digestion

Jun He; Shuang Ren; Shicheng Zhang; Gang Luo

doi:10.1016/j.biortech.2021.125856

Modification of hydrochar increased the capacity to promote anaerobic digestion

Bioresour Technol. 2021 Dec:341:125856. doi: 10.1016/j.biortech.2021.125856. Epub 2021 Aug 30.

Authors

Jun He¹, Shuang Ren¹, Shicheng Zhang², Gang Luo³

Affiliations

¹ Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China.
² Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
³ Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address: gangl@fudan.edu.cn.

PMID: 34479140
DOI: 10.1016/j.biortech.2021.125856

Abstract

Hydrochar has been demonstrated to increase methane production rate during anaerobic digestion (AD) of organic wastes/wastewater by facilitating direct interspecies electron transfer (DIET). The present study compared the hydrochars prepared at different conditions (260 °C-1 h, 260 °C-8 h, 320 °C-1 h and 320 °C-8 h) on AD of glucose. Hydrochar prepared at lower temperature and residence time (260 °C-1 h) resulted in the highest methane production rate, which was 237% higher of control experiment without hydrochar. Modification of hydrochar (260 °C-1 h) by ball-milling further increased the capacity to increase methane production rate. Hydrothermal liquefaction (HTL) conditions affected the surface oxygen-containing functional groups that related with DIET, and hydrochar (260 °C-1 h) had higher peaks relating with C-O and O-H functional groups. Ball-milling enhanced the formation of such groups. Microbial analysis showed hydrochar (260 °C-1 h) by ball-milling resulted in the formation of different microbial communities as compared with control experiments, and Azospira and Methanosarcina were enriched, which might be involved in DIET.

Keywords: Anaerobic digestion; Hydrochar; Microbial analysis; Surface oxygen-containing functional groups.

MeSH terms

Anaerobiosis
Methane*
Oxygen
Sewage*
Temperature

Substances

Sewage
Methane
Oxygen