Effect of continuous micro-aeration on hydrogen production by coal bio-fermentation

ABSTRACT

In order to study the effect of micro-aeration on hydrogen production from coal, bituminous coal D from the Yima mining area was selected. An experiment to simulate hydrogen production by bio-fermentation was carried out with mine water as the source of bacteria. The results show that with an increasing aeration rate, the hydrogen production continuously decreased. At the end of gas production, the total hydrogen production under aeration rates of 0.0015 L/h, 0.015 L/h and 0.15 L/h was 3.60 mL/g, 1.50 mL/g and 0.58 mL/g, respectively. The molar concentrations of volatile fatty acids (VFAs) in the reaction liquid increased continuously, and the pH decreased overall. The COD content of the liquid phase first increased and then decreased. The COD degradation rates of three different aeration rates at the end of hydrogen production were 43.67%, 16.26% and 5.87%, respectively. With the increasing aeration rate, the dominant hydrogen producing bacteria during bio-fermentation gradually changed from Clostridium to Propionibacterium, and the type of fermentation also changed from butyric acid-type fermentation to propionic acid-type fermentation. In conclusion, the experimental results provide a theoretical basis for exploring hydrogen production via coal bio-fermentation under continuous micro-aeration.

KEYWORDS:

• Coal
• micro-aeration
• bio-fermentation
• fermentation type
• hydrogen production

Highlights

1. New idea for hydrogen production from coal bio-fermentation

2. The effect of aeration rate on COD degradation rate was improved

3. Enriched the utilization way of coal bio- fermentation

4. Hydrogen production by continuous micro-aeration coal bio-fermentation can accelerate the goal of “carbon peak, carbon neutralization”

Acknowledgments

This work was supported by the National Natural Science Foundation of China (41972178, 42072193); and the Outstanding Youth Science Foundation of Henan Province (202300410168); and the Young Backbone Teacher Foundation of Henan Province (2017XQG-02).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [419721178, 42072193]; The Young Backbone Teacher Foundation of Henan Province [2017XQG-02]; The Outstanding Youth Science Foundation of Henan Province [202300410168].

Notes on contributors

Hongyu Guo

Hongyu Guo Visualization, Investigation, Methodology. Affiliated to School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China; Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region, Jiaozuo 454000, China.

Saisai Li

Saisai Li Software, Data curation. Affiliated to School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China.

Zhenwei Yang

Zhenwei Yang Conceptualization, Funding acquisition. Affiliated to Institute of Resources and Environment Henan Polytechnic University, Jiaozuo 454000, China.

Xianbo Su

Xianbo Su Resources. Affiliated to Institute of Resources and Environment Henan Polytechnic University, Jiaozuo 454000, China; Institute of Resources and Environment Henan Polytechnic University, Jiaozuo 454000, China; Unconventional Gas Research Institute, Henan Polytechnic University, Jiaozuo, 454000, China

Shufeng Zhao

Shufeng Zhao Data curation. Affiliated to School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China

Bo Song

Bo Song Writing- Reviewing and Editing. Affiliated to School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China.

Shangwei Shi

Shangwei Shi Software, Validation. Affiliated to School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China.