Abstract
Coal is an important energy source whose consumption increases continuously. One of the many ways to use coal is coal blending, which is a very effective technique in power stations. However, coal blending generates unsuspected problems, one of which is ash deposition that causes slagging and fouling. In fact, most blends accelerate and generate heavier ash depositions than their parent coals.
This work investigates the characteristics of ash behavior including fusibility and deposition when blending both bituminous and subbituminous coals in a pulverized coal combustion. Two coals used in Japan were used for this study: bituminous (Bit-A) and subbituminous coal (Sub-A). In order to investigate, the blending ratio was changed. A Thermomechanical analysis (TMA) and a Drop tube furnace (DTF) were used for ash fusibility and deposit, respectively. Ash components were determined using X-ray fluorescence at the coal research center of Idemitsu Kosan Co., Ltd., in Japan. These tests revealed that as the blending ratio of Sub-A increased, fusibility in the TMA and the melting propensity increased. Capture efficiency and energy-based growth increased with the blending ratio, and were highest at 80%. Finally, a new approach based on the relation between ash fusibility and deposit derived for predicting adhesion tendency on blended coals was created by deriving the relation between the fusibility and deposit results that affected slag formation.
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Ho Lim received his B.S. in Mechanical Engineering from Kumoh Institute of Technology, 2009. He then received his M.S. degree from Pusan National University in 2011. He is currently a Ph.D. student at Pusan National University.
Lkhagvadorj Shagdarsuren received his B.S. in Mechanical Engineering from Mongolian University of Science and Technology, 2008. He is currently an Integrated Ph.D. course student at Pusan National University.
Seung-Mo Kim received his B.S. (1999) and M.S. (2001) in Environmental Engineering from Hoseo University. He then received his Ph.D. degree in Mechanical Engineering from Osaka University in 2004. Dr. Kim is currently a research professor at Pusan Clean Coal Center at Pusan National University.
Akihiro Hoshino received his B.S. from Kanazawa University in 2006. He then received his M.S. degree in Chemical Engineering from Gunma University in 2008. He is currently a research engineer at the Coal & Environment Research Laboratory of Idemitsu Kosan Co., Ltd.
Toru Yamashita received his M.S. in Mineral Resources and Material Engineering from Waseda University in 1989. He then received his Ph.D. degree in Chemical Engineering from Chubu University in 2008. He is currently a general manager at the Coal & Environment Research Laboratory of Idemitsu Kosan Co., Ltd.
Chung-Hwan Jeon received his B.S. (1985), M.S. (1987) and Ph.D. (1994) degrees from Pusan National University. Dr. Jeon is currently a professor in the school of Mechanical Engineering at Pusan National University, and is currently serving as a director of Pusan Clean Coal Center.
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Lim, H., Shagdarsuren, L., Kim, SM. et al. The effect of blending of bituminous and sub-bituminous coals on ash fusibility and deposition formation. J Mech Sci Technol 30, 1413–1420 (2016). https://doi.org/10.1007/s12206-016-0249-8
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DOI: https://doi.org/10.1007/s12206-016-0249-8