高炉煤气水解-氧化耦合脱硫技术中试研究

PILOT STUDY OF BLOW FURNACE GAS HYDROLYSIS-OXIDATION COUPLED DESULFURIZATION TECHNOLOGY

钢铁行业是我国国民经济重要的支柱性产业。2021年我国粗钢产量居世界第一。在火电行业全面推进超低排放后,钢铁行业成为工业部门最大的大气污染排放源,工艺产污环节多、污染物排放量大。钢铁企业“三气”中高炉煤气占64%,是产量最大的可燃气体,产量高达8000~10000亿m^(3)/a。针对高炉煤气气量大、成分复杂、硫含量低的特点,研发了高炉煤气水解-氧化耦合脱硫技术,并通过高炉煤气脱硫中试平台评价了中试系统的运行效果。从中试运行效果看,特制的双层预处理剂有效去除了高炉煤气中的粉尘和HCl,降低了杂质对水解催化剂的影响;针对高炉煤气研发的水解催化剂可实现COS的高效脱除,同时大大延长了使用寿命,整个中试期间始终未在水解塔出口检出COS,且水解塔的压降低于3 kPa;通过对工况和催化剂添加量的精准把控,脱硫效率在95%以上,氧化脱硫系统运行平稳。中试系统的脱硫效率可满足高炉煤气应用端高炉热风炉的超低排放要求,且压力损失低,同时也验证了脱硫技术和反应器设计的合理性。

The steel industry is an important pillar industry of China's national economy.In 2021,China's crude steel production ranked first in the world.After the thermal power industry has comprehensively promoted ultra-low emissions,the steel industry has become the largest source of air pollution emissions in the industrial sector,with many process pollution links and large pollutant emissions.Blast furnace gas accounts for 64%of the"three gases"of iron and steel enterprises,which is the largest combustible gas in output,with an output of 8000~10000 billion m^(3)/a.Aiming at the characteristics of large gas volume,complex composition and low sulfur content of blast furnace gas,the combined desulfurization technology of hydrolysis-oxidation of blast furnace gas was developed,and the operation effect of the pilot system was evaluated by the blast furnace gas desulfurization pilot platform.From the pilot operation effect,the special double-layer pretreatment agent effectively removed the dust and HCl in the blast furnace gas,and reduced the influence of impurities on the hydrolysis catalyst.The hydrolysis catalyst developed for blast furnace gas can achieve efficient removal of COS,and at the same time greatly extend the service life,COS has not been detected at the outlet of the hydrolysis tower during the entire pilot period,and the pressure of the hydrolysis column has been reduced to 3 kPa.Through the precise control of the working conditions and catalyst addition,the desulfurization efficiency is above 95%,and the oxidative desulfurization system runs smoothly.The desulfurization efficiency of the pilot system can meet the ultra-low emission requirements of the blast furnace hot blast furnace at the blast furnace gas application end,and the pressure loss is low,which also verifies the rationality of the desulfurization technology and reactor design.