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2024 Vol.33, Issue 4 Preview Page

Research Paper

A Study on the Optimal Process Parameters for Recycling of Electric Arc Furnace Dust (EAFD) by Rotary Kiln

Rotary Kiln에 의한 전기로 제강분진(EAFD)의 재활용을 위한 최적의 공정변수에 관한 연구

Jae-hong Yoon1*
,
Chi-hyun Yoon2
,
Myoung-won Lee1
윤 재홍1*
,
윤 치현2
,
이 명원1
1School of Materials Science & Engineering, Changwon National University, Sarimdong 9, Changwon, Gyeongnam 51140, Korea
2Production Technology Team, Hwangjo Co., Ltd, 149, Duryu-gil, Angang-eup, Gyeongju-si, Gyeongbuk-do, Korea
1창원대학교 공과대학 재료공학부
2㈜황조 생산기술부
*Corresponding Author
31 August 2024. pp. 47-61
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Abstract

As a recycling technology for recovering zinc contained in large amounts in electric arc furnace dust (EAFD), the most commercialized technology in the world is the Wealz Kiln Process. The Wealz Kiln Process is a process in which components such as Zn and Pb in EAFD are reduced/volatile (endothermic reaction) in high-temperature Kiln and then re-oxidized (exothermic reaction) in the gas phase and recovered in the form of Crude zinc oxide (60wt%Zn) in the Bag Filter installed at the rear end of Kiln. In this study, an experimental Wealz kiln was produced to investigate the optimal process variable value for practical application to the recycling process of large-scale kiln on a commercial scale. Additionally, Pellets containing EAFD, reducing agents, and limestone were continuously loaded into Kiln, and the amount of input, heating temperature, and residence time were examined to obtain the optimal crude zinc oxide recovery rate. In addition, the optimal manufacturing conditions of Pellets (drum tilt angle, moisture addition, mixing time, etc.) were also investigated. In addition, referring to the SiO2-CaO-FeO ternary system diagram, the formation behavior of a low melting point compound, a reaction product inside Kiln according to the change in the basicity of Pellet, and the reactivity (adhesion) with the castable constructed on the inner wall of Kiln were investigated. In addition, in order to quantitatively investigate the possibility of using anthracite as a substitute for Coke, a reducing agent, changes in the temperature distribution inside Kiln, where oxidation/reduction reactions occur due to an increase in the amount of anthracite, the quality of Crude zinc oxide, and the behavior of tar in anthracite were also investigated.

Keywords
Electric Arc Furnace Dust Recycling
Rotary Kiln Manufacture
Optimal Process Variables
Basicity and Refractory
Coke and Anthracite

전기로 제강분진(EAFD : Electric Arc Furnace Dust) 중에 다량 함유되어있는 아연을 회수하기 위한 재활용 기술로서, 현재 세계적으로 가장 많이 상용화된 기술은 Wealz Kiln Process이다. Wealz Kiln Process에서는, 제강분진 중의 Zn, Pb 등과 같은 성분들을 고온의 Kiln에서 환원/휘발(흡열반응)시킨 후에 다시 기체상에서 재산화(발열반응)시켜 후단에 설치된 Bag Filter에서 조산화아연(60wt%Zn)의 형태로 회수하는 프로세스이다. 본 연구에서는, 상업용 규모의 대형 kiln의 재활용 공정에 실제로 적용하기 위한 최적의 공정변수 값을 조사하기 위해서, 실험용 Wealz kiln을 제작하였다. 그리고, 전기로 제강분진과 환원제, 석회석을 혼합한 Pellet을 연속적으로 Kiln에 장입하면서, 조산화아연 회수율을 얻기 위한 최적의 장입량과 가열온도, 체류시간 등을 조사하였다. 또한 Pellet의 최적의 제조조건( Drum 경사각, 수분의 첨가량, 혼합시간 등)도 조사하였다. 또한, SiO2-CaO-FeO 3성분계 상태도를 참고하여, Pellet의 염기도(basicity)의 변화에 따른 Kiln 내부에서의 저융점 화합물의 생성거동과 Kiln내벽에 시공된 Castable과의 반응성(부착성)을 평가하여 보았다. 그리고, 환원제인 Coke의 대체제로서 무연탄의 사용 가능성을 실질적으로 평가하기 위하여, 무연탄의 첨가량 증가에 따라서 산화/환원반응이 일어나는 Kiln 내부의 온도분포변화, 조산화아연의 품위, 무연탄 중의 타르(Tar)의 거동에 대해서도 조사하였다.

키워드
전기로제강분진 재활용
로타리 키른 제작
공정변수
염기도와 내화물
코크스와 무연탄
References
1

S. Nakazawa, T. Azakami, A. Yazawa, 1999 : Simulation of Pyrometallurgical Processing of EAF Dust Bearing Nonferrous Metals, MMIJ, 115(10), pp.781-786.

10.2473/shigentosozai.115.781
2

Chi hyun Yoon, Myungwon Lee, Jaehong Yoon, et al., 2014 : A Study on Roasting Refinement of Crude-ZnO from Electric Arc Furnace Steel Dust, J. of Korean Inst. of Resources Recycling, 23(1), pp.58-63.

10.7844/kirr.2014.23.1.58
3

Jaehong Yoon, Chihyun Yoon, Myungwon Lee, 2017 : A Study on Kinetic of Volatilization Behavior of Metal Elements Contained in Electric Arc Furnace Dust, J. of Korean Inst. of Resources Recycling, 26(3), pp.17-25.

4

Jaehong Yoon, Chi-hyun Yoon, 2021 : A Study on the Separation and Recovery of Useful Metallic Elements(Zn, Pb) from the 2nd Dust in Refining of Crude-Zinc Oxide, Resources Recycling, 30(1), pp.66-76.

10.7844/kirr.2021.30.1.66
5

Jaehong Yoon, Chihyun Yoon, Hirofumi Sugimoto, et al., 2023 : A Study on the Resource Recovery of Fe-Clinker generated in the Recycling Process of Electric Arc Furnace Dust, Resources Recycling, 32(1), pp.50-59.

10.7844/kirr.2023.32.1.50
6

K. B. Yoon, 2000 : A Study on Reduction Treatment of EAF's Dusts Mixed with Millscale, J. of Korean Inst. of Resources Recycling, 9(6), pp.45-52.

7

B. S. Kim, J. M. Yoo, J. T. Park, et al., 2006 : A Kinetic Study of the Carbothermic Reduction of Zinc Oxide with Various Additives, Material Transactions, 47(9), pp.2421-2426.

10.2320/matertrans.47.2421
8

H. Oda, T. Ibaraki, Y. Abe, 2006 : Dust Recycling System by the Rotary Hearth Furnace(RHF), Nippon-steel Technical Report, No.94, July 2006, pp.147-152.

9

J. Ruetten, 2009 : The Topical Waelz Process for Recycling of EAF Dust State of the Art and Future Challenges, 10th Inst. Sympo. on East Asian Resource Recycling Technology (Earth 2009), 2-6 November 2009, Jejudo, Korea.

10

B. J. Jung, S. M. Bae, 2001 : A Study on Behavior of Volatile Compounds by Carbon Materials in Initial Reduction Stage of EAF dust, J. of Korean Soild Wastes Engineering Society, 18(2), pp.121-128.

11

Xiao Yan Liu, Eckehard Specht, 2006 : Mean residence time and hold-up of solids in rotary kilns, Chemical Engineering Science, 61(15), pp.5176-5181.

10.1016/j.ces.2006.03.054
12

Sai, P. S. T., Surender, G. D., Damodaran A. D., et al., 1990 : Residence time distribution and material flow studies in a rotary kiln, Metallurgical Transactions B, 21(6), pp.1005-1011.

10.1007/BF02670271
13

A. Yazawa, T. Azakami, K. Itagaki, et al., 1999 : Metal Smelting and Refining Engineering, pp.107-110, 2nd Edition, Japan Institute of Metals and Metals Society of Japan, Japan.

14

Ingrid J. Paredes, Bereket Yohannes, Heather Emady, et al., 2017 : The effect of operating conditions on the residence time distribution and axial dispersion coefficient of a cohesive powder in a rotary kiln, Chemical Engineering Science, 158(2), pp.50-57

10.1016/j.ces.2016.09.028
15

Zisheng Zhang, Yuanqing Wu, Hong Li, et al., 2018 : A simple step-change method to determine mean residence time in rotary kiln and a predictive model at low inclination, Powder Technology, 333(15), pp.30-37.

10.1016/j.powtec.2018.04.002
Information
  • Publisher :The Korean Institute of Resources Recycling
  • Publisher(Ko) :한국자원리싸이클링학회
  • Journal Title :Resources Recycling
  • Journal Title(Ko) :자원리싸이클링
  • Volume : 33
  • No :4
  • Pages :47-61
  • Received Date : 2024-08-09
  • Revised Date : 2024-08-21
  • Accepted Date : 2024-08-22
  • DOI :https://doi.org/10.7844/kirr.2024.33.4.47
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