Strategies for heat recovery in a reverse flow reactor designed to lessen coal mine methane emissions test

ABSTRACT

Thermal pollution resulting from the release of ventilation air methane (VAM) has emerged as a pressing concern in coal mining. This study aims to address this issue by harnessing the waste VAM energy and converting it into reusable resources, employing an efficient thermal flow reversal reactor. The research investigates five distinct heat extraction strategies and compares their performance. The numerical analysis focuses on transient heat recovery performance by employing a two-step reaction mechanism. Furthermore, the study uncovers the heat transfer characteristics of heat exchange tubes and conducts an analysis of construction costs and profit periods for the different strategies. The findings indicate that the central heat recovery strategy exhibits inferior recovery performance, resulting in higher outlet temperatures and lower extracted power. Conversely, the end recovery strategy successfully reduces heat loss by 56%. The two-sided strategy demonstrates better recovery performance, maintaining an average outlet temperature of 311 K. Additionally, the heat recovery efficiency of the heat exchange tube is approximately 85.6%. Although the combination strategy appears to reduce outlet heat loss, it results in an extended investment payback period.

KEYWORDS:

• Heat recovery strategy
• Reverse flow reactor
• Heat exchange tube
• Efficiency
• Coal mine methane
• Heat extracted power

Acknowledgements

This study was supported by Shandong Provincial Natural Science Foundation, China (ZR2018MEE006 and ZR2017LEE019) and the National Key R&D Program of China (2017YFB0603504-2)

Disclosure statement

The author declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Additional information

Notes on contributors

Yuqi Zhou

Yuqi Zhou is currently studying for a doctorate at Shandong University of Technology. Her current research field is low-grade energy gas combustion and waste heat recovery and utilization.

Yongqi Liu

Yongqi Liu is currently a professor and doctoral supervisor at Shandong University of Technology. He graduated from University of Shanghai for Science and Technology with a doctor's degree. At present, he is the president of Energy Conservation Technology Research Institute of Shandong University of Technology, and also the director of China Internal Combustion Engine Society. The research direction is low-grade energy combustion, heat and mass transfer, and waste heat utilization.

Yueyue Shi

Yueyue Shi graduated from Shandong University of Technology with a doctoral degree. During her doctoral studies, she focused on the recovery of ventilation air methane and the characteristics of steam-water circulation.

Yuqiu Zhang

Yuqiu Zhang is currently studying for a doctorate at Shandong University of Technology. Her current research field is the flow of solid particles.

Junrui Shi

Junrui Shi is currently a professor and doctoral supervisor at Shandong University of Technology. He graduated from Dalian University of Technology with a doctor's degree. His research direction is the utilization of low calorific value gases. He took charge of projects such as the study of non-equilibrium characteristics of low-speed filtration combustion.

Peng Sun

Peng Sun is currently an associate professor and master's supervisor at Shandong University of Technology. He graduated from Xi'an Jiaotong University with a doctor's degree. His research interests include gas-solid two-phase flow, heat transfer, and combustion.