焦炭工艺副产氢气在多晶硅生产中的应用研究

Application of Coke Process by-Product Hydrogen inPolysilicon Production

煤炭焦化工艺副产大量焦炉煤气,焦炉煤气中氢气含量为55%~60%(体积分数),经提纯处理后氢气可广泛应用于化工行业。氢气是光伏多晶硅生产的主要原料之一,在多晶硅生产过程中用点较多、用量较大。本文主要研究焦炭工艺副产氢气经过PSA深度纯化后用于多晶硅生产系统的可行性。实验结果表明,经过深度纯化后的焦炭工艺副产氢气纯度稳定在5 N以上且不含有机杂质甲烷,满足多晶硅生产的要求。焦炭工艺副产氢气生产的多晶硅杂质含量大部分均低于原水解制氢,虽然C杂质含量波动较大,但其均值达到电子级2级品要求。采用煤焦化工艺副产的氢气替代传统的电解水制氢,多晶硅生产成本可降低270~360元/t。

Coal coking process produces a large amount of coke oven gas.The hydrogen content in coke oven gas is process 55%-60%(volume fraction).After purification,hydrogen can be widely used in the chemical industry.Hydrogen is one of the main raw materials for polysilicon production.Hydrogen is used in many places and in large quantities in the production of polysilicon.This paper mainly studied the feasibility of coke process by-product hydrogen after PSA deep purification for polysilicon production system.The experimental results show that the purity of hydrogen produced by the coke process after deep purification is stable above 5N,and does not contain organic impurity methane,which meets the requirements of polysilicon production for hydrogen quality.The content of polysilicon impurities produced by the coke process by-product hydrogen is mostly lower than that of the original hydrolysis hydrogen production.Although the content of C impurities fluctuates greatly,its average value meets the requirements of electronic grade 2 products.The production cost of polysilicon can be reduced by 270-360 yuan/t by using hydrogen produced by coal coking process instead of traditional electrolytic water to produce hydrogen.