A Study on Distribution and Characteristics of Heavy Metals and Unburned Carbon in Bottom Ash of Coal-Fired Power Plant

Jeong Heum Nam; Min Sik Kim; Heon Chan Kang

doi:10.12972/ksmer.2014.51.6.786

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2014 Vol.51, Issue 6 Preview Page Next Page

Research Paper

A Study on Distribution and Characteristics of Heavy Metals and Unburned Carbon in Bottom Ash of Coal-Fired Power Plant 화력발전소 바닥재의 중금속 및 미연탄소 분포 특성 연구

31 December 2014. pp. 786-793

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Abstract

The distribution and characteristics of heavy metals and unburned carbon in bottom ash from the coal-fired power plant have been investigated. The purpose of this study is to evaluate the recycling application of bottom ash after removal of heavy metals and unburned carbon. When the bottom ash was analyzed by the Standard Method of the Soil Environment Conservation, the concentration of Cr was 5.26 mg/kg, exceeding the warning standard (5 mg/kg). According to the magnetic separation, it found that iron was present in the form of magnetite or hematite. The result of unburned carbon concentration according to the specific gravity, showed that the concentration of unburned carbon increases as the specific gravity decreases. After Heavy-liquid separation was performed to identify the minerals of heavy metals, the sinks were then analyzed by the XRD method. The sinks mainly consist of ilmenite, hematite, magnetite, nickel sulfide, pyrite. From the result of SEM/EDS analysis, it found that chromium is contented in pyrite.

Keywords

Coal-fired Power plant

Bottom Ash

Unburned carbon

Heavy metals

Chromium

화력발전소 바닥재로부터 중금속 및 미연탄소를 제거하여 활용 가능성을 평가하는 목적으로 H 화력발전소 바닥재의 중금속 및 미연탄소 분포 특성 연구 실시하였다. 중금속 함량을 분석한 결과, Cr이 5.26 mg/kg으로 1지역 우려기준을 초과하고 있었다. 자력분리에 따른 바닥재 시료 특성을 알아본 결과, 철분은 주로 적철석과 자철석의 형태로 존재하고 있었다. 비중에 따라 바닥재내에 미연탄소를 분석한 결과, 비중 2.1 이상에서는 미연탄소가 나타나지 않았으며, 비중이 낮아질수록 미연탄소 함량이 많아지는 것을 알 수 있었다. 바닥재내에 중금속 형태를 알아보기 위해 중액선별을 실시한 결과, 침강물에서 티탄철석, 적철석, 자철석, 황화니켈, 황철석 등이 존재하는 것을 확인하였고, SEM/EDS결과, Cr이 황철석에 고용되어 있는 것을 알 수 있었다.

키워드

화력발전소

바닥재

미연탄소

중금속

크롬

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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 : 51
No :6
Pages :786-793
Received Date : 2014-08-22
Revised Date : 2014-12-06
Accepted Date : 2014-12-19
DOI :https://doi.org/10.12972/ksmer.2014.51.6.786

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

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