Dielectric Properites of Iron Sulfide in Coal by Microwave Irradiation

Byoung-Gon Kim; Chong-Lyuck Park; Jae-Ryeong Lee

doi:10.12972/ksmer.2013.50.6.838

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2013 Vol.50, Issue 6 Preview Page Next Page

Research Paper

Dielectric Properites of Iron Sulfide in Coal by Microwave Irradiation 마이크로웨이브를 이용한 석탄 철황화물들의 유전특성 조사

31 December 2013. pp. 838-847

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Abstract

This study focuss on a dielectric and transformation properties of iron sulfide including pyrite, pyrrhotite, and troilite by microwave heation. The relative magnetic loss factors of pyrite at both 915 MHz and 2.45 GHz are between 0.2 and 0.4. This shows that pyrite is not a strong magnetic substance. Also, the decrease of the relative magnetic constant of pyrite is caused by the increase of electrical conductivity of sample, as indicated by the variation of permittivity. The large dielectric constant and loss factor of pyrrhotite at temperatures below 200°C suggest that this phase has good microwave absorption capability at microwave frequency. The dielectric constant and loss factor of troilite are found to be highly temperature and frequency dependent.

Keywords

Coal Desulfurization

Microwave

Dielectric Property

Iron Sulfide

Phase transition

본 연구에서는 마이크로웨이브 조사에 의한 철황화물(황철석, 자황철석, 단유철석)의 유전특성과 상전이 거동에 대하여 조사하였다. 황철석의 상대자기손실계수는 915 MHz와 2.45 GHz 모두에서 0.2~0.4로 나타났으며, 이것은 황철석은 강자성체 물질이 아님을 나타냈다. 또한 황철석의 상대자기상수는 유전율의 변화를 나타내는 전기전도도가 증가함에 따라 감소하는 경향을 보였다. 자황철석은 200°C 이하에서 높은 유전상수와 손실계수를 갖는 것으로 조사되었으며, 이것은 자황철석의 마이크로웨이브 흡수율이 높은 물질임을 보여주는 결과이다. 단유철석의 유전율과 손실계수의 온도 및 주파수 의존성을 조사한 결과, 마이크로웨이브 조사에 의해 효율적으로 가열되는 것을 알 수 있었다.

키워드

석탄탈황

마이크로웨이브

유전특성

철황화물

상전이

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Information

Publisher :The Korean Society of Mineral and Energy Resources Engineers
Publisher(Ko) :한국자원공학회
Journal Title :Journal of the Korean Society of Mineral and Energy Resources Engineers
Journal Title(Ko) :한국자원공학회지
Volume : 50
No :6
Pages :838-847
Received Date : 2013-10-04
Revised Date : 2013-12-05
Accepted Date : 2013-12-12
DOI :https://doi.org/10.12972/ksmer.2013.50.6.838

Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

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