Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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The study of geopolymer utilization of reclaimed ash by using magnetic separation method

자력선별법을 이용한 화력 발전소 매립회의 지오폴리머 원료화 연구

  • Kim, Kangduk (Department of Advanced Materials Engineering, Kyonggi University)
  • Received : 2017.08.29
  • Accepted : 2017.09.27
  • Published : 2017.10.31
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Abstract

Using a magnetic separation process, pond ash generated in thermoelectric power plants was separated into magnetic materials and nonmagnetic materials in order to make it into a raw material of geopolymers and unburned carbon; screening characteristics according to the particle sizes and magnet strength levels of the pond ash were observed. Based on the results of magnetic separation into fine particle (0.15~0.84 mm) and rough particle (0.84~2.4 mm) pond ash using 3000 G magnets, the weight fraction and ignition loss of nonmagnetic materials were found to be higher than those of magnetic materials, regardless of the particle size. In the case of fine particle pond ash, when the magnet strength was increased from 3000 G to 10000 G, even those materials that were weakly magnetic were separated into magnetic materials, leading to drastic increases in the weight fraction of magnetic materials, such that the ignition loss accounted for 66.9 % (22.8 wt%) of the entire ignition loss of 32.6 wt%, despite of the low ignition loss. Based on the results of measurement of the compressive strength levels of geopolymers made of magnetic-separated rough particle pond ash, the compressive strength of geopolymers made of magnetic materials containing small amounts of unburned carbon was found to be 20 MPa.

화력발전소에서 발생되는 매립회의 지오폴리머 원료화를 위하여 자력선별 공정을 이용하여 자성체와 비자성체로 분리하였으며, 매립회의 입도 및 자석의 세기에 따른 미연탄소의 선별 특성을 관찰하였다. 3000 G 자석을 이용한 세립(0.15~0.84 mm)과 조립(0.84~2.4 mm) 매립회의 자력선별 결과, 매립회는 입도에 상관없이 비자성체의 무게분율과 강열감량이 자성체보다 높게 나타났으며, 세립 매립회의 경우 자석의 세기를 3000 G에서 10000 G로 증가시키면, 약한 자성을 띠는 물질들도 자성체로 분리됨에 따라 자성체의 무게 분율이 급격히 증가되면서 낮은 강열감량에도 불구하고 전체 강열감량의 32.6 wt%의 66.9 %(22.8 wt%)를 차지하였다. 자력 선별된 조립 매립회로 제조된 지오폴리머의 재령일별 압축강도 측정결과, 미연탄이 적게 포함된 자성체로 제조된 지오폴리머의 압축강도가 20 MPa를 나타내었다.

Keywords

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