Next Article in Journal
Numerical Simulation of Crystalline Silicon Heterojunction Solar Cells with Different p-Type a-SiOx Window Layer
Next Article in Special Issue
Development of a Modified Plug-Flow Anaerobic Digester for Biogas Production from Animal Manures
Previous Article in Journal
Experimental and Numerical Examination of Naturally-Aged Foam-VIP Composites
Previous Article in Special Issue
Development of an Optimised Chinese Dome Digester Enables Smaller Reactor Volumes; Pilot Scale Performance
Open AccessArticle

Effect of Mixing Regimes on Cow Manure Digestion in Impeller Mixed, Unmixed and Chinese Dome Digesters

1
Centre for Energy Research and Development, Obafemi Awolowo University, 220282 Ile-ife, Nigeria
2
sub-Department Environmental Technology, Wageningen University and Research, 6708 WG Wageningen, The Netherlands
*
Author to whom correspondence should be addressed.
Energies 2019, 12(13), 2540; https://doi.org/10.3390/en12132540
Received: 10 April 2019 / Revised: 13 June 2019 / Accepted: 13 June 2019 / Published: 2 July 2019
(This article belongs to the Special Issue Biogas for Rural Areas)
This study examines the effect of mixing on the performance of anaerobic digestion of cow manure in Chinese dome digesters (CDDs) at ambient temperatures (27–32 °C) in comparison with impeller mixed digesters (STRs) and unmixed digesters (UMDs) at the laboratory scale. The CDD is a type of household digester used in rural and pre-urban areas of developing countries for cooking. They are mixed by hydraulic variation during gas production and gas use. Six digesters (two of each type) were operated at two different influent total solids (TS) concentration, at a hydraulic retention time (HRT) of 30 days for 319 days. The STRs were mixed at 55 rpm, 10 min/hour; the unmixed digesters were not mixed, and the Chinese dome digesters were mixed once a day releasing the stored biogas under pressure. The reactors exhibited different specific biogas production and treatment efficiencies at steady state conditions. The STR 1 exhibited the highest methane (CH4) production and treatment efficiency (volatile solid (VS) reduction), followed by STR 2. The CDDs performed better (10% more methane) than the UMDs, but less (approx. 8%) compared to STRs. The mixing regime via hydraulic variation in the CDD was limited despite a higher volumetric biogas rate and therefore requires optimization. View Full-Text
Keywords: mixing; Chinese dome digester; impeller mixed digester; unstirred digester; hydraulically mixed; total solids (TS) concentration mixing; Chinese dome digester; impeller mixed digester; unstirred digester; hydraulically mixed; total solids (TS) concentration
Show Figures

Figure 1

MDPI and ACS Style

Jegede, A.O.; Zeeman, G.; Bruning, H. Effect of Mixing Regimes on Cow Manure Digestion in Impeller Mixed, Unmixed and Chinese Dome Digesters. Energies 2019, 12, 2540.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop