Kinetic analysis and mathematical modeling of low-rank coal drying by using swirl fluidized bed dryer on varied angles of guide vane and temperatures

ABSTRACT

Low-rank coal is currently widely used as fuel to cover the increasing needs of boilers. This kind of coal must be upgraded due to its high moisture content to increase its quality. The drying using a fluidized swirl bed has not been studied to reduce the moisture content of Low-Rank Coal. In contrast, the drying kinetic model has never been found. This study used the angle of guide vanes (AGV) 10°, 20°, and 30° to produce swirl flow. Experiments with varying temperatures used temperatures of 40°C, 45°C, and 50°C. The purpose of this work was to determine the drying characteristics, the best-drying kinetics models, the effective moisture diffusion value, SMER, MER, and SEC on swirl fluidized bed drying. The study results show that the Khazaei and Rational drying kinetic model was the most suitable for the two experimental variations. For experiments with varying AGV, the R2 values obtained are 0.9989–0.9992 and 0.9980–0.9983, while for the variable temperature, the values are 0.9990–0.9992 and 0.9983–0.9992 for each model. The research also found that the smaller AGV angle and higher temperature result in a faster drying rate and consume less energy.

KEYWORDS:

• Kinetic analysis
• low-rank coal
• swirl fluidized bed
• angle of guide vane
• temperature

Author’s note

The author(s) declare(s) that there is no conflict of interest regarding the publication of this article. The authors confirmed that the data and the paper are free of plagiarism.

Acknowledgements

The author would like to thank the students of Mechanical Engineering ITS Surabaya and Universitas Sumatera Utara for the assistance provided for this research.

Disclosure statement

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

Additional information

Notes on contributors

Melvin Emil Simanjuntak

Melvin Emil Simanjuntak completed his PhD at Sepuluh Nopember Institute of Technology, Surabaya, Indonesia, in 2018. He is an associate professor in the Mechanical Engineering Department at Medan State Polytechnic, Indonesia. His research interests are drying, biomass combustion, CFD, and fluid machinery.

M. B. H. Sitorus

M. B. H. Sitorus completed his Master’s degree at Sepuluh Nopember Institute of Technology, Surabaya, Indonesia, in 2011. He is a Lecturer in the Mechanical Engineering department at Medan State Polytechnic, Indonesia. His research interests are in solid mechanics and welding.

Idham Kamil

Idham Kamil completed his PhD at North Sumatera University, Medan, Indonesia, in 2023. He is a lecturer in the Mechanical Engineering department at Medan State Polytechnic, Indonesia and interest is heat transfer.

Berta Br Ginting

Berta Br Ginting completed her Master’s at North Sumatera University, Medan, Indonesia. 2011. She is an associate professor in the Mechanical Engineering department at Medan State Polytechnic, Indonesia. Her research interest is in biodiesel and the machining process.

Teng Sutrisno

Teng Sutrisno completed his PhD at Sepuluh Nopember Institute of Technology, Surabaya, Indonesia, in 2017. He is a lecturer in the Mechanical Engineering Department at Petra Christian University Surabaya, Indonesia. His research interests are fluid mechanics, heat transfer, computational fluid dynamics, and internal combustion engines.

Wawan Aries Widodo

Wawan Aries Widodo completed his PhD at Sepuluh Nopember Institute of Technology, Surabaya, Indonesia, in 2010. He is an associate professor in the Mechanical Engineering Department at Sepuluh Nopember Institute of Technology, Surabaya, Indonesia. His research interests are fluid mechanics, powerplant systems, and CFD.

Prabowo Prabowo

Prabowo Prabowo completed his PhD degree at Hiroshima University, Japan, in 1997. He is a Professor in the Mechanical Engineering Department at Sepuluh Nopember Institute of Technology, Surabaya, Indonesia. His research interests are convective heat transfer, geothermal, organic Rankine cycle, and CFD.

Tulus Burhanuddin Sitorus

Tulus Burhanuddin Sitorus completed his PhD at North Sumatera University, Medan, Indonesia, in 2017. Now, he is an associate professor in the Mechanical Engineering Department at North Sumatera University, Medan, Indonesia. His research is mainly in internal combustion engines and refrigeration.