Study On Desulfurization Of Low Energy Consumption From Blast Furnace Gas And Desulfurization Of Product Gas With High CO₂ Content

Iron and steel blast furnace gas(BFG),as a flammable gas produced in the process of blast furnace ironmaking,can realize the reuse of energy and reduce the energy consumption of the steel industry.However,the SO2 produced by combustion pollutes the atmospheric environment and endangers human health.Therefore,the research of BFG desulfurization technology has become the top priority.Pre-combustion desulfurization can avoid the problem of high desulfurization cost caused by large gas H2S Adsorption process respectively,and the following two pvolume of combustion products and scattered emission points after combustion.Precombustion desulfurization mainly focuses on the preparation of H2S removal materials and technology research.In 2019,the Ministry of Ecology and Environment issued strict environmental standards on sulfur emissions.H2S removal alone cannot meet the emission requirements,and desulfurization and emission reduction targets can be achieved through H2S removal combined with carbonyl sulfur(COS)removal process.At present,the commonly used pretreatment desulfurization process is catalytic hydrolysis COS and H2S adsorption process.In order to obtain a higher desulfurization rate,the process needs to first increase the temperature of the raw material to improve the hydrolysis rate of COS,and then reduce the temperature of the raw material to improve the adsorption rate of H2S.Therefore,the process has the problem of high energy consumption.In addition,sulfur compounds such as H2S and COS are found in the high-concentration CO2 product gas produced by desulfurization and deacidification processes such as low-temperature methanol washing.Total sulfur content directly affects CO2 recycling,so in order to meet the standard of CO2 recycling,it is necessary to carry out fine desulfurization of high concentration CO2.However,the lack of research on the effect of operating conditions under high CO2 content on the desulfurization efficiency of the process affects the engineering application of the process.In view of the problems existing in the desulfurization process combining the catalytic hydrolysis of carbonyl sulfur and H2S Adsorption,Aspen Plus and Aspen Adsorption software were used to simulate the hydrolysis process of carbonyl sulfur and arts of work were completed.Firstly,explore the influence of temperature and pressure,the key influencing factors of energy consumption,on total sulfur removal and energy consumption,and identify the desulfurization scenarios with low energy consumption that meet the emission reduction standards.The results show that the hydrolysis pressure has little effect on energy consumption and total sulfur.The total sulfur content decreased with the increase of adsorption pressure,but the change of energy consumption was small.Hydrolysis temperature and adsorption temperature are the key factors affecting desulfurization and energy consumption.Secondly,explore the influence of CO2 volume fraction,temperature,pressure and other operating conditions on the desulfurization effect of product gas with high CO2 content,and according to the above rules,take a steel plant blast furnace gas decarbonization product gas as a case to study its desulfurization effect.According to the above rules,the desulfurization effect of decarbonization product gas of blast furnace in a steel plant was studied as a case.The results show that the volume fraction of CO2 and temperature are negatively correlated with the total sulfur removal rate,and the increase of pressure helps to improve the total sulfur removal rate.The study case of decarburization product gas from blast furnace of a steel plant also confirms the above rule,and some scenarios meet the desulfurization standards.