LAPSE:2022.0053
Published Article
LAPSE:2022.0053
Model-Based Analysis of Feedback Control Strategies in Aerobic Biotrickling Filters for Biogas Desulfurization
Luis Rafael López, Mabel Mora, Caroline Van der Heyden, Juan Antonio Baeza, Eveline Volcke, David Gabriel
October 12, 2022
Biotrickling filters are one of the most widely used biological technologies to perform biogas desulfurization. Their industrial application has been hampered due to the difficulty to achieve a robust and reliable operation of this bioreactor. Specifically, biotrickling filters process performance is affected mostly by fluctuations in the hydrogen sulfide (H2S) loading rate due to changes in the gas inlet concentration or in the volumetric gas flowrate. The process can be controlled by means of the regulation of the air flowrate (AFR) to control the oxygen (O2) gas outlet concentration ([O2]out) and the trickling liquid velocity (TLV) to control the H2S gas outlet concentration ([H2S]out). In this work, efforts were placed towards the understanding and development of control strategies in biological H2S removal in a biotrickling filter under aerobic conditions. Classical proportional and proportional-integral feedback controllers were applied in a model of an aerobic biotrickling filter for biogas desulfurization. Two different control loops were studied: (i) AFR Closed-Loop based on AFR regulation to control the [O2]out, and (ii) TLV Closed-Loop based on TLV regulation to control the [H2S]out. AFR regulation span was limited to values so that corresponds to biogas dilution factors that would give a biogas mixture with a minimum methane content in air, far from those values required to obtain an explosive mixture. A minimum TLV of 5.9 m h−1 was applied to provide the nutrients and moisture to the packed bed and a maximum TLV of 28.3 m h−1 was set to prevent biotrickling filter (BTF) flooding. Control loops were evaluated with a stepwise increase from 2000 ppmv until 6000 ppmv and with changes in the biogas flowrate using stepwise increments from 61.5 L h−1 (EBRT = 118 s) to 184.5 L h−1 (EBRT = 48.4 s). Controller parameters were determined based on time-integral criteria and simple criteria such as stability and oscillatory controller response. Before implementing the control strategies, two different mass transfer correlations were evaluated to study the effect of the manipulable variables. Open-loop behavior was also studied to determine the impact of control strategies on process performance variables such as removal efficiency, sulfate and sulfur selectivity, and oxygen consumption. AFR regulation efficiently controlled [O2]out; however, the impact on process performance parameters was not as great as when TLV was regulated to control [H2S]out. This model-based analysis provided valuable information about the controllability limits of each strategy and the impact that each strategy can have on the process performance.
Keywords
biogas, biotrickling filter, control strategies, feedback control, H2S removal, process modeling
Suggested Citation
López LR, Mora M, Van der Heyden C, Baeza JA, Volcke E, Gabriel D. Model-Based Analysis of Feedback Control Strategies in Aerobic Biotrickling Filters for Biogas Desulfurization. (2022). LAPSE:2022.0053
Author Affiliations
López LR: GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, Escola d’Enginyeria, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
Mora M: GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, Escola d’Enginyeria, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
Van der Heyden C: Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
Baeza JA: GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, Escola d’Enginyeria, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain [ORCID]
Volcke E: Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
Gabriel D: GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, Escola d’Enginyeria, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain [ORCID]
Journal Name
Processes
Volume
9
Issue
2
First Page
208
Year
2021
Publication Date
2021-01-22
Published Version
ISSN
2227-9717
Version Comments
Original Submission
Other Meta
PII: pr9020208, Publication Type: Journal Article
Record Map
Published Article

LAPSE:2022.0053
This Record
External Link

doi:10.3390/pr9020208
Publisher Version
Download
Files
[Download 1v1.pdf] (3.5 MB)
Oct 12, 2022
Main Article
License
CC BY 4.0
Meta
Record Statistics
Record Views
153
Version History
[v1] (Original Submission)
Oct 12, 2022
 
Verified by curator on
Oct 12, 2022
This Version Number
v1
Citations
Most Recent
This Version
URL Here
https://psecommunity.org/LAPSE:2022.0053
 
Original Submitter
Thomas A. Adams II
Links to Related Works
Directly Related to This Work
Publisher Version