A Study on Effective Separation of Fine Fly Ash using an Electrostatic Separator

doi:None

All Issue

2005 Vol.42, Issue 4 Preview Page

A Study on Effective Separation of Fine Fly Ash using an Electrostatic Separator 정전선별기에 의한 미립석탄회의 효과적 분리에 대한 연구: 한오형, 박병욱
Oh-Hyung Han and Byoung-Wook Park

31 August 2005. pp. 403-409

PDF

Abstract

Recently, bituminous coals used in coal-fired power plants are pulverized into finer particles in order to increase the combustion efficiency. Because of these reasons most of fly ash produced here consist more than 70 wt.% passing 500 mesh. Therefore, it is more difficult to separate the unburned carbon from the fly ash. This study was conducted to separate the unburned carbon from fine fly ash more efficiently using an exciting electrostatic separator with several modifications. The modifications included (i) undercoating the V-shaped trough with insulation super high voltage coating (ii) undercoating with plastic coating and (iii) filling the separated electrodes with plastic insulator. These procedures increased the separation efficiency more than 1.5～2.0 times with the formation of strong and high-density electric fields at the end of each separated electrode.

Keywords

Fine particle fly ash

Conductive induction

Super high voltage coating

Under coating

High density electric field

최근 국내 석탄 화력발전소에서 연료로 사용하고 있는 수입유연탄은 비교적 품위가 높으며 이들의 연소효율을 높이기 위해 미분쇄를 하기 때문에 여기서 발생되는 석탄회는 70 wt.% 이상이 500 mesh보다 작은 미립으로 이루어져 있다. 그러므로 이전에 개발된 석탄회의 선별기술을 사용하여 미립의 미연탄소분을 제거하는데 어려움이 따르게 된다. 본 연구에서는 미립의 석탄회로부터 미연탄소분을 효과적으로 분리하기위해 이미 개발된 정전유도에 의한 선별장치의 V형 전극바닥에 초고압코팅제와 플라스틱 페인트로 코팅하는 방법과 바닥전극을 분할하여 분할된 전극사이를 절연체인 플라스틱으로 채워 적용전압을 높이는 방법을 사용하였다. 그 결과 전극 끝부분에 강하고 치밀한 전기장이 형성되어 기존의 선별장치에 비해 1.5～2.0배의 선별효율을 얻을 수 있었다.

키워드

미립 석탄회

정전유도

초고압 절연코팅제

바닥코팅

고밀도 전기장

References

Anderson, J.M., Maroto-Valer, M.M., Anderson, C.A. and Battista, J.J., 1999, “Assessing the Potential of Unburned carbon as a filler for Carbon Artifacts,” Proceedings 1999 International Ash Utilization Symposium, Paper No 16, MAROTO32. pdf(CD-ROM publication).
Ban, H., Li, T.X., Schaefer, J.L., Neathery, J.K. and Stencel, J.M., 1997, “Fundamental of Triboelectrostatic Separation: A Disscution on Particle Charge, Particle Size and Separation,” Preprint, Annual Meeting of the Society of Mining, Metallurgy, and Exploration, Inc. (SME), Denver, CO., p. 1-5.
Bittner, J.D. 1997, “STI Fly Ash Separation System: Operating History at New England Power's Brayton Point Plant,” 12th International Symposium on Coal Combusion By-Product(CCB) Management and Use. EPRI TR- 107055-V2, Vol. 2, p. 62-1-64-5.
Edward K. Levy and Carlos Herrera, 1977, “Ash Beneficiation Using Fluidized Bed Separation,” 1997 International Ash Utilization Symposium, Lexington, KY., p.467-470.
Han, O,H., Jeon, H.S., Yoon, R.H., 2001, “Development of a Electrostatic Separation Technology for Removal of Unburned Carbon from fly Ash,” Journal of the Korean Institute of Mineral and Energy Resources Engineers, Vol. 38 p.416-423.
Hepher, N.M., Apparatus for Separating Particulate Materials, U.S. Patent, 1985, 4,556,486.
Inculet, I.I., Norberg, K.E. and Hepher, N.M., 1985, Method of Apparatus for Separating Particulate Materials, U.S. Patent, 4,517,078.
Kelly, E.G. and Spottiswood, D. J., 1989, “The Theory Electrostatic Separations: A Review parts Ⅱ. Particle charging:” Mineral Engineering, Vol. 2, No. 2, p. 193-205.
Maroto-Valer, M.M., Taulbee, D.N., Schobert, H.H., Hower, C.H. and Anderson, J.M 1999, “Use of Unburned Carbon in Fly Ash as Precursor for the Development of Activated Carbons,” Proceedings 1999 International Ash Utilization Symposium, Paper No. 80, MAROTO22. pdf(CD-ROM publication).
Mazumder, M.K., Tennal, K.B. and David Lindquist, 1994, “Electrostatic Beneficiation of Coal,” Proceedings of Tenth Annual Coal Preparation, Utilization and Environmental control Contractors Conference, Pittsburgh, PA, Vol. 1, p.111-116.
Stencel, J.M., Schaefer, J.L., Ban, H. and Finseth, D., 1998, Method and Apparatus for Triboelectric-Centrifugal Separation, U.S. Patent, 5,755,333.
Tennal, K.B., Mazumder, M.K., Lindquist, J., Zhang, J. and Tendeku, F., “Triboelectric Separation of Granular Materials,” 1997, IEEE Industry Application Society Annual Meeting, Louisiana , New Orleans, Vol. 3, p. 1724-1729.
Thomas, B., Mason, M.O., Liu, Y.A. and Squires, A.M., 1989, “Identifying in Shallow Vibrated Beds,” Powder Technology, Vol.57, p. 267-280.
Yoon, R.H., Han, O.H., Yan, E.S., Park, B.W., 2001, Electrostatic Method of Separating Particulate Materials, U.S. Patent, 6,320,148.

Information

Publisher :The Korean Society of Mineral and Energy Resources Engineers
Publisher(Ko) :한국자원공학회
Journal Title :Journal of the Korean Society for Geosystem Engineering
Journal Title(Ko) :한국지구시스템공학회지
Volume : 42
No :4
Pages :403-409

[1] Anderson, J.M., Maroto-Valer, M.M., Anderson, C.A. and Battista, J.J., 1999, “Assessing the Potential of Unburned carbon as a filler for Carbon Artifacts,” Proceedings 1999 International Ash Utilization Symposium, Paper No 16, MAROTO32. pdf(CD-ROM publication).

[2] Ban, H., Li, T.X., Schaefer, J.L., Neathery, J.K. and Stencel, J.M., 1997, “Fundamental of Triboelectrostatic Separation: A Disscution on Particle Charge, Particle Size and Separation,” Preprint, Annual Meeting of the Society of Mining, Metallurgy, and Exploration, Inc. (SME), Denver, CO., p. 1-5.

[3] Bittner, J.D. 1997, “STI Fly Ash Separation System: Operating History at New England Power's Brayton Point Plant,” 12th International Symposium on Coal Combusion By-Product(CCB) Management and Use. EPRI TR- 107055-V2, Vol. 2, p. 62-1-64-5.

[4] Edward K. Levy and Carlos Herrera, 1977, “Ash Beneficiation Using Fluidized Bed Separation,” 1997 International Ash Utilization Symposium, Lexington, KY., p.467-470.

[5] Han, O,H., Jeon, H.S., Yoon, R.H., 2001, “Development of a Electrostatic Separation Technology for Removal of Unburned Carbon from fly Ash,” Journal of the Korean Institute of Mineral and Energy Resources Engineers, Vol. 38 p.416-423.

[6] Hepher, N.M., Apparatus for Separating Particulate Materials, U.S. Patent, 1985, 4,556,486.

[7] Inculet, I.I., Norberg, K.E. and Hepher, N.M., 1985, Method of Apparatus for Separating Particulate Materials, U.S. Patent, 4,517,078.

[8] Kelly, E.G. and Spottiswood, D. J., 1989, “The Theory Electrostatic Separations: A Review parts Ⅱ. Particle charging:” Mineral Engineering, Vol. 2, No. 2, p. 193-205.

[9] Maroto-Valer, M.M., Taulbee, D.N., Schobert, H.H., Hower, C.H. and Anderson, J.M 1999, “Use of Unburned Carbon in Fly Ash as Precursor for the Development of Activated Carbons,” Proceedings 1999 International Ash Utilization Symposium, Paper No. 80, MAROTO22. pdf(CD-ROM publication).

[10] Mazumder, M.K., Tennal, K.B. and David Lindquist, 1994, “Electrostatic Beneficiation of Coal,” Proceedings of Tenth Annual Coal Preparation, Utilization and Environmental control Contractors Conference, Pittsburgh, PA, Vol. 1, p.111-116.

[11] Stencel, J.M., Schaefer, J.L., Ban, H. and Finseth, D., 1998, Method and Apparatus for Triboelectric-Centrifugal Separation, U.S. Patent, 5,755,333.

[12] Tennal, K.B., Mazumder, M.K., Lindquist, J., Zhang, J. and Tendeku, F., “Triboelectric Separation of Granular Materials,” 1997, IEEE Industry Application Society Annual Meeting, Louisiana , New Orleans, Vol. 3, p. 1724-1729.

[13] Thomas, B., Mason, M.O., Liu, Y.A. and Squires, A.M., 1989, “Identifying in Shallow Vibrated Beds,” Powder Technology, Vol.57, p. 267-280.

[14] Yoon, R.H., Han, O.H., Yan, E.S., Park, B.W., 2001, Electrostatic Method of Separating Particulate Materials, U.S. Patent, 6,320,148.

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

All Issue