火法提纯冶金级硅制备太阳能级硅的最新研究进展

雷云; 马晓东; 王烨; 陈志远; 任永生; 马文会; Kazuki Morita

doi:10.1007/s12613-022-2418-3

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文章导航 > 矿物冶金与材料学报（英文） > 2022 > 29(4): 767-782

Yun Lei, Xiaodong Ma, Ye Wang, Zhiyuan Chen, Yongsheng Ren, Wenhui Ma, and Kazuki Morita, Recent progress in upgrading metallurgical-grade silicon to solar-grade silicon via pyrometallurgical routes, Int. J. Miner. Metall. Mater., 29(2022), No. 4, pp. 767-782. https://doi.org/10.1007/s12613-022-2418-3

Cite this article as:

Yun Lei, Xiaodong Ma, Ye Wang, Zhiyuan Chen, Yongsheng Ren, Wenhui Ma, and Kazuki Morita, Recent progress in upgrading metallurgical-grade silicon to solar-grade silicon via pyrometallurgical routes, Int. J. Miner. Metall. Mater., 29(2022), No. 4, pp. 767-782. https://doi.org/10.1007/s12613-022-2418-3

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特约综述

火法提纯冶金级硅制备太阳能级硅的最新研究进展

1)
昆明理工大学冶金与能源工程学院，昆明 650093，中国
2)
Sustainable Minerals Institute, The University of Queensland, St Lucia 4072, QLD, Australia
3)
四川大学化学工程学院, 成都 610065, 中国
4)
Separation and Conversion Technology, Flemish Institute for Technological Research, Mol 2400, Belgium
5)
Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan

* 共同第一作者

通讯作者:
Kazuki Morita E-mail: kzmorita@material.t.u-kyo.ac.jp

文章亮点

(1) 回顾了采用火法冶金技术提纯冶金级硅的研究进展。

(2) 对各种火法冶金提纯硅技术进行了总结和评价。

(3) 提出了一种提纯冶金级硅或回收硅废料的新方法。

中文摘要

硅基光伏太阳能作为一种可再生的绿色能源发展迅速。硅基太阳能电池的广泛使用需要使用大量的太阳能级硅(99.9999%)来制造硅基太阳电池硅片。多晶太阳能级硅的制备主要采用化学法，以改良西门子法为代表;然而，传统的化学法涉及一系列复杂的化学反应，制备过程具有腐蚀性并使用各种危险的化学试剂。另一方面，随着硅基太阳能电池的普及，将产生大量复杂难处理的失效太阳能电池和硅切割废料；然而，利用现在的化学法很难回收这些光伏废料，需要提出新的方法来制备太阳能级硅和回收硅基光伏废料。冶金法提纯硅技术具有一定的应用前景，但如何去除冶金级硅中的B和P的杂质是急需解决的关键问题。针对这一问题，研究者们提出了各种火法冶金方法以提高冶金级硅中B和P杂质的去除率。本文对目前现有的造渣法、氯化法、真空挥发法和溶剂精炼法进行了回顾，并对这四种方法的基本原理以及近年来有代表性的研究工作进行了总结和讨论。结果表明，溶剂精制法是目前最有希望、最环保的低成本太阳能级硅制备方法，也是目前冶金法提纯硅的研究热点。最后，本文提出了一种采用溶剂精炼、造渣或真空定向凝固相结合的新方法进行冶金级硅的提纯和硅废料的回收，以实现绿色低成本制备太阳能级硅和回收光伏硅废料。

关键词:

Invited Review

Recent progress in upgrading metallurgical-grade silicon to solar-grade silicon via pyrometallurgical routes

+ Author Affiliations

1)
Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China
2)
Sustainable Minerals Institute, The University of Queensland, St Lucia 4072, QLD, Australia
3)
School of Chemical Engineering, Sichuan University, Chengdu 610065, China
4)
Separation and Conversion Technology, Flemish Institute for Technological Research, Mol 2400, Belgium
5)
Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan

*These authors contributed equally to this work.

Corresponding author:
Kazuki Morita E-mail: kzmorita@material.t.u-kyo.ac.jp
Received: 7 October 2021; Revised: 17 December 2021; Accepted: 17 January 2022; Available online: 18 January 2022

Abstract

Abstract

Si-based photovoltaic solar power has been rapidly developed as a renewable and green energy source. The widespread use of Si-based solar cells requires large amounts of solar-grade Si (SoG-Si) to manufacture Si wafers. Chemical routes, mainly the modified Siemens process, have dominated the preparation of polycrystalline SoG-Si; however, traditional chemical techniques employ a series of complex chemical reactions involving various corrosive and hazardous reagents. In addition, large amounts of complex waste solar cells and Si kerf slurry waste gradually accumulate and are difficult to recycle using these approaches. New methods are required to meet the demand for SoG-Si preparation and Si waste recycling. The metallurgical route shows promise but is hindered by the problem of eliminating B and P from metallurgical-grade Si (MG-Si). Various pyrometallurgical treatments have been proposed to enhance the removal of B and P from MG-Si. This article reviews Si refining with slag treatment, chlorination, vacuum evaporation, and solvent refining, and summarizes and discusses the basic principles and recent representative studies of the four methods. Among these, solvent refining is the most promising and environmentally friendly approach for obtaining low-cost SoG-Si and is a popular research topic. Finally, a simple and green approach, i.e., a combination of solvent refining, slag treatment, or vacuum directional solidification, is proposed for low-cost SoG-Si preparation using MG-Si or Si wastes as raw materials.
- silicon refining;
- solar-grade silicon;
- solvent refining;
- vacuum evaporation;
- slag treatment;
- Si kerf slurry waste

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References

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