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The Study on the Combustion and Ash Deposition Characteristics of Ash Free Coal and Residue Coal in a Drop Tube Furnace

DTF를 이용한 무회분 석탄과 잔탄의 연소 및 회 점착 특성에 관한 연구

Moon, Byeung Ho;Kim, Jin Ho;Sh, Lkhagvadorj;Kim, Gyu Bo;Jeon, Chung Hwan
문병호;김진호;락워더러지;김규보;전충환

  • Received : 2015.07.20
  • Accepted : 2015.09.08
  • Published : 2015.12.31

Abstract

Recently, much research has been put into finding the causes and solutions of slagging/fouling problems that occur at the end of the boiler. This slagging/fouling, caused by low-rank coal's ash, disturbs the thermal power and greatly reduces efficiency. In environmental aspects, such as NOx pollution, governments have been implementing restrictions on the quantity of emission gases that can be released into the atmosphere. To solve these problems, research on Ash Free Coal (AFC), which eliminates ash from low-rank coal, is in progress. AFC has advantages over similar high-rank coals because it increases the heating value of the low grade coal, reduces the contaminants that are emitted, and decreases slagging/fouling problems. In this study, using a DTF, the changes of NOx emissions, unburned carbon, and the characteristics of ash deposition were identified. KCH raw coal, AFC extracted from KCH, residue coal, Glencore, and Mixed Coal (Glencore 85wt% and residue coal 15wt%) were studied. Results showed that AFC had a significantly lower emission of NOx compared to that of the raw coal and residue coal. Also, the residue coal showed a higher reactivity compared to raw coal. And finally, In the case of the residue coal and mixed coal, they showed a lower ash deposition than that of low-rank coal.

Keywords

Ash Free Coal;Unburnded carbon;NOx;Ash Deposition;DTF(Drop Tube Furnace)

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Acknowledgement

Supported by : 한국에너지 기술평가원(KETEP)