软锰矿干法烧结烟气脱硫研究

发布时间：2018-07-05 20:56

  本文选题：低品位软锰矿 + 烧结烟气　； 参考：《贵州大学》2015年硕士论文

【摘要】：针对我国钢铁行业SO2气体排放量大,传统石灰法、氨-硫铵法、氧化镁法等湿法脱硫技术存在运行成本较高、设备腐蚀结垢、占地面积大、消耗大量水和二次污染等问题,论文提出软锰矿烧结烟气干法脱硫工艺。该方法将低品位软锰矿粉直接接触高温烧结烟气,利用软锰矿中二氧化锰(MnO2)的氧化性和烧结烟气中二氧化硫(SO2)的还原性发生氧化还原反应,在脱除烧结烟气中低浓度SO2的同时得到高附加值的硫酸锰(MnSO4),从热力学角度和动力学角度详细分析了软锰矿干法烧结烟气脱硫工艺的可行性。主要研究内容如下:根据软锰矿干法烧结烟气脱硫系统中可能发生的反应,对其进行热力学计算,并绘制了Mn-S-O系、Fe-S-O系等温优势区相图。结果表明:在烧结烟气的温度范围内(120-180℃)脱硫具有很大的反应趋势,反应进行的很彻底,升高温度对脱硫反应不利;同时软锰矿与SO2反应的过程中对氧分压的要求不大,能够得到MnSO4和Fe2O3共存产物,理论上认为低品位软锰矿可实现选择性硫化。采用压缩空气和纯SO2气体混合后合成模拟烟气,在U型玻璃管中进行脱硫试验,考察了烧结烟气温度、软锰矿粒度、SO2浓度和气体流速等因素对脱硫率的影响。结果表明:软锰矿干法脱硫率随烧结烟气温度的升高而升高、随软锰矿目数的增加而增加、随进气口SO2浓度的增加而减少、随混合气体流速的增加而减少,每组试验达到70%左右的脱硫率,脱硫后的烟气可以达到排放标准。同时对软锰矿干法脱除烧结烟气中低含量SO2的动力学进行了研究,得出:干法脱硫过程由外传质和内扩散控制,与界面化学反应无关,可由反应速率随温度的变化试验、表观活化能及试验数据计算分析得到,同时可得到软锰矿干法脱硫的宏观动力学方程为:其中。本课题的研究有望解决钢铁行业中低浓度含硫烧结烟气污染问题,同时最大程度上实现了低品位软锰矿的资源化利用,为后续锰制品的制备奠定了基础,对含硫烧结烟气治理和锰制品行业的发展具有重要意义。
[Abstract]:In view of the large amount of so _ 2 emission in iron and steel industry in our country, the problems of traditional lime method, ammonia ammonium sulfate process, magnesium oxide method and so on, such as high operating cost, corrosion and scaling of equipment, large area of land, large consumption of water and secondary pollution, etc. The dry desulfurization process of pyrolusite sintering flue gas is put forward in this paper. In this method, the low-grade pyrolusite powder was directly contacted with the high-temperature sintering flue gas, and the oxidation of manganese dioxide (MNO _ 2) in the pyrolusite and the reduction of sulfur dioxide (so _ 2) in the sinter flue gas were redox. Manganese sulfate (MnSO _ 4) with high added value was obtained by removing so _ 2 from sintering flue gas. The feasibility of dry sintering flue gas desulfurization process with pyrolusite was analyzed in detail from the point of view of thermodynamics and kinetics. The main research contents are as follows: according to the possible reactions in the dry sintering flue gas desulfurization system of pyrolusite, thermodynamic calculation is carried out, and the phase diagram of the isothermal dominant zone of Mn-S-O system is drawn. The results show that desulphurization has a great reaction tendency in the temperature range of 120 ~ 180 鈩，

本文编号：2101758