Fundamental Aspects of Silicon Refining

硅精炼的基本方面

• 批准号: 346130-2012
• 负责人: Barati, Mansoor
• 金额: $ 2.11万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=595620
• 关键词: Fundamental; Aspects; Silicon; Refining

Silicon is the primary material for manufacture of solar cells, accounting for over 90 percent of today's market for photovoltaic (PV) materials. Nevertheless, the limited supply and high price of Si have created a major obstacle to realizing the technology's potential for becoming a major electricity producer. This is chiefly because currently there is no dedicated process for production of solar grade silicon (SoG-Si) at acceptable cost and high production rate. In the past several years, our Sustainable Materials Processing Research Group, along with several other groups have been striving for developing technologies that would produce SoG-Si at a lower cost compared to today's processes. Most of the emphasis in such research works has been development of process(es) through experimental work followed by optimization, that will reach commercial scale in the shortest time possible. Similar to any other development, often the fundamental aspects that are essential to optimizing the technology have not been looked into, in details in several cases. Though this discovery grant, the fundamental aspects of several silicon purification techniques will be investigated. In particular, four topics related to the thermodynamics of Si refining are of interest and will be studied (a) distribution of impurities (P and B) between solid silicon and binary silicon alloys with Fe, Cu, and Zn, (b) thermodynamics of impurity distribution between slag and metal for slags containing various oxides and under a range of oxygen potentials, (c) thermodynamics of P and B distribution between alloys of Si (with Cu, Al) and molten salt, and (d) solubility of silica in cryolite based molten salts. This kind of research is essential in supporting the previous activities related to developing a technology for generation of SoG-Si. In addition, such fundamental studies are critical in creating a knowledge base in the relatively young field of high purity Si processing by pyrometalllurgical techniques. The long term benefits are generation of clean energy through advancing solar energy field, and training several graduate and undergraduate students with expertise in the fields of materials processing, energy materials, and characterization.

硅是制造太阳能电池的主要材料，占当今光伏（PV）材料市场的90%以上。然而，硅的有限供应和高价格已经成为实现该技术成为主要电力生产商潜力的主要障碍。这主要是因为目前还没有以可接受的成本和高生产率生产太阳级硅（SoG-Si）的专用工艺。在过去的几年里，我们的可持续材料加工研究小组，以及其他几个小组一直在努力开发技术，以更低的成本生产SoG-Si与今天的工艺相比。这类研究工作的重点是通过实验工作开发工艺，然后进行优化，以便在最短的时间内达到商业规模。与任何其他开发类似，通常对优化技术至关重要的基本方面还没有进行研究，在几个案例中有详细的研究。虽然这一发现获得批准，但将对几种硅净化技术的基本方面进行研究。特别是，与硅精炼热力学相关的四个主题是值得研究的(a)固体硅和含铁、铜和锌的二元硅合金之间杂质（P和B）的分布，(B)含各种氧化物和氧势范围内的炉渣和金属之间杂质分布的热力学，(c)硅（含铜、铝）合金和熔盐之间P和B分布的热力学，(d)二氧化硅在冰晶石基熔盐中的溶解度。这种研究对于支持与开发SoG-Si生成技术有关的先前活动至关重要。此外，这些基础研究对于在相对年轻的高温冶金技术高纯硅加工领域建立知识库至关重要。长期利益是通过推进太阳能领域产生清洁能源，并培养几名具有材料加工，能源材料和表征领域专业知识的研究生和本科生。