Influence of different substrates on the performance of a two-stage high pressure anaerobic digestion system

Publication Type

Journal contribution (peer reviewed)

Authors

Lemmer, A., Chen, Y., Lindner, J., Wonneberger, A.M., Zielonka, S., Oechsner, H., Jungbluth, T.

Year of publication

2015

Published in

Bioresource Technology

Pubisher

Elsevier Ltd.

Band/Volume

178/

ISBN / ISSN / eISSN

09608524

DOI

10.1016/j.biortech.2014.09.118

Page (from - to)

313-318

Keywords

Ammoniak

The two-stage autogenerative high-pressure digestion technique is a novel and promising approach for the production of gaseous fuels or upgraded biogas. This new technique is described in the patent DE 10 2011 015415 A1 and integrates biogas production, its upgrading and pressure boosting in one process. Anaerobic digestion under elevated pressure conditions leads to decreasing pH-values in the digestate due to the augmented formation of carboxylic acid. Model calculations carried out to evaluate the two-stage design showed that the pH-value in the pressurized anaerobic filter has a major influence on the methane content of the biogas produced. Within this study, the influence of the nitrogen content as one of the most important buffering substances on the performance of the system has been tested. The results show that higher NH₄ contents lead to higher pH-values in the digester and as a consequence to higher methane contents. © 2014 Elsevier Ltd.