The effects of digestate pyrolysis liquid on the thermophilic anaerobic digestion of sewage sludge — Perspective for a centralized biogas plant using thermal hydrolysis pretreatment

Hämäläinen, Anna and Kokko, Marika and Chatterjee, Pritha and et al, . (2022) The effects of digestate pyrolysis liquid on the thermophilic anaerobic digestion of sewage sludge — Perspective for a centralized biogas plant using thermal hydrolysis pretreatment. Waste Management, 147. pp. 73-82. ISSN 0956-053X

Text
Waste_Management.pdf - Published Version
Available under License Creative Commons Attribution.
Download (952kB)

Abstract

The use of pyrolysis process to valorize digestate from anaerobic digestion (AD) of municipal sewage sludge for biochar production was piloted in a central biogas plant. The pyrolysis also generates pyrolysis liquid with high organics and nutrient contents that currently has no value and requires treatment, which could potentially be done in AD. As the pyrolysis liquid may contain inhibitory compounds, we investigated the effects of adding the pyrolysis liquid on AD of sewage sludge and thermal hydrolysis pretreated sewage sludge (THSS) simulating the full-scale centralized biogas plant conditions. In batch assays, the pyrolysis liquid as such did not produce any methane, and the 1% and 5% (v/w) shares suppressed the methane production from THSS by 14–19%, while a smaller decrease in methane production was observed with sewage sludge. However, in the semi-continuous reactor experiments, pyrolysis liquid at a 1% (v/w) share was added in sewage sludge or THSS feed without affecting the methane yields or digestate characteristics. The laboratory results indicated that pyrolysis liquid can be treated in AD, while extrapolating the results to the centralized biogas plant indicated minor increase in the overall methane production and an increased potential for ammonium recovery. © 2022 The Author(s)

[error in script]

IITH Creators:

IITH Creators	ORCiD
Chatterjee, Pritha	https://orcid.org/0000-0002-7989-6131

Item Type:

Article

Additional Information:

The financial support from the Maj and Tor Nessling Foundation (Anna Hämäläinen), the Industrial Research Fund at Tampere University of Technology (Anna Hämäläinen), and Gasum Ltd. are gratefully acknowledged. The authors are grateful to Gasum Ltd. Topinoja biogas plant for providing the materials and to the laboratory staff member Antti Nuottajärvi for providing and servicing the equipment used.

Uncontrolled Keywords:

Anaerobic digestion; Digested sewage sludge; Pyrolysis liquid; Thermal prehydrolysis

Subjects:

Civil Engineering

Divisions:

Department of Civil Engineering

Depositing User:

. LibTrainee 2021

Date Deposited:

18 Oct 2022 07:17

Last Modified:

18 Oct 2022 07:17