Purification method of dispersing gas guided in to metallic silicon

Abstract

The invention discloses a dispersing gas leading-in metal silicon purification method which aims at simplifying the traditional ventilation leading-in mode so as to cause the gas to fully react with the molten silicon and prolong the service life of the silicon container. The invention firstly uses micron grade fireresistant metal-oxide particles, formulates a dispersing microporous by high-pressure forming to get through a gas discharging head which is arranged in the center of the bottom of the silicon container; a gas bottom conduit passes through the bottom of the silicon container so as to connect a gas source; and a gas control valve is arranged at the combination part of the gas source. According to the gas type and the molten silicon volume, the intake pressure is adjusted, taking the molten silicon surface not forming significantly boiling as better, and simultaneously, the gas supply can be stopped or the gas type can be changed. After each operation is finished and the residue at the container wall is removed, the silicon container can be used continuously. The invention overcomes the disadvantage that the existing gas discharging head is easy to be obstructed when the gas supply is stopped; the practice proves that the gas discharging head which is manufactured with the method can continue to be used for 50 times when the oxygen is used, and 100 times when the argon is used.

Description

technical field [0001] The invention relates to a gas introduction method in the metal purification process, in particular to a gas introduction method in the metal silicon purification process. Background technique [0002] In recent years, demand for silicon as a solar cell material has rapidly increased due to heightened concerns about energy / environmental issues such as the consumption of fossil fuel energy and global warming issues. With the rapid development of the photovoltaic industry, the growth rate of polysilicon demand for solar cells is higher than that of semiconductor polysilicon. In 1994, the total output of solar cells in the world was only 69MW, but in 2004 it was close to 1200MW, an increase of 17 times in just 10 years. Experts predict that the solar photovoltaic industry will surpass nuclear power to become one of the most important basic energy sources in the first half of the 21st century. [0003] At present, there are three main sources of solar po...

AI Technical Summary

Problems solved by technology

This method overcomes the shortcomings of the loose combination of particles in the previous method, but the particles used in this method are relatively large, and their diameters are on the order of mm, so the ventilation is not uniform enough; the gaps between the particles are large, and in the case of a sudden interruption of the gas supply , it is still difficult to avoid the phenomenon of sucking

Melt is easy to enter the gap and block