Research Developments of Metallurgical Grade Silicon Refining by Al Si Alloying Process
Silicon production for photovoltaic industry using a metallurgical refining process of metallurgical grade silicon(MG Si) has been attractive to many researchers,especially in China,due to its high efficiency,energy saving and environment friendly features.Generally,the process is combined with two or more refining steps,including hydrometallurgical purification,alloying refining,directional solidification,vacuum smelting,etc.MG Si refining by Al Si alloying process shows high efficiency for impurity removal with low operation temperature and simple equipment,and is getting more and more attention recently.In present work,principle,refining procedure and research results of Al Si alloying process are described.In addition,the recent proceeding of the process is summarized and its further development is propected.