Effect of hydraulic retention time on suppression of methanogens during a continuous biohydrogen production process using molasses wastewater. Issue 1 (2nd January 2017)

• Record Type: Journal Article
• Authors: Yun, Jeong Hee; Cho, Kyung-Suk
• Is Part Of: Journal of environmental science and health. Volume 52:Issue 1(2017)
• Page Start: 37
• Page End: 44
• Publication Date: 2017-01-02
• Subjects: Biohydrogen -- HRT control -- methanogenesis -- molasses wastewater -- suppression; Environmental engineering -- Periodicals; Environmental sciences -- Periodicals; Ecology -- periodicals; Hazardous Substances -- periodicals; 628
• DOI: 10.1080/10934529.2016.1221221
• Languages: English
• ISSNs: 1093-4529

Abstract

ABSTRACT: This study was undertaken to investigate the reduction of the hydraulic retention time (HRT) to decrease methane generation and recover hydrogen production during the long-term operation of biohydrogen production in a continuous stirred tank reactor (CSTR) using molasses wastewater. Reduction of HRT can be a simple and economic method to immediately control unfavorable methane generated during continuous operation of a hydrogen production system. The steady-state performance of the CSTR showed a hydrogen content of 41.3 ± 3.30% and a hydrogen production rate (HPR) of 63.7 ± 10.01 mmol-H2 L −1 d −1 under an organic loading rate (OLR) of 29.7 g CODL −1 at an HRT of 24 h. Increase in the methane level above 40% during long-term operation caused decrease in the hydrogen content and HPR to 5.9 ± 1.6% and 2.1 ± 1.1 mmoL-H2 L −1 d −1, respectively. When methane increased to a high level over 40%, the CSTR at the HRT of 24 h was operated at the HRT of 12 h. Reduction of the HRT from 24 to 12 h led to decrease in the methane content of 12.1 ± 4.44% and recovery of the HPR value to 48.9 ± 15.37 mmol-H2 L −1 d −1 over a duration of 13–22 d. When methane is generated in a continuously operated reactor, reduction of the HRT can be an easy way to suppress methanogens and recover hydrogen production without any additives or extra treatments.