QQ客服 官方微博 反馈留言

题名	铁、磷矿石熔融还原及煤氧浸没喷射气化研究
作者	郭占成
学位类别	博士
答辩日期	1992-06-30
授予单位	中国科学院研究生院
授予地点	北京
导师	许志宏
学位专业	化学工艺
中文摘要	八十年代以来，世界各国将钢铁冶金新技术研究开发重点转向熔融还原新流程。本论文就铁浴煤氧造气与熔融还原过程的若干问题进行了基础研究，并在此基础上对熔融还原磷进行了探讨。将煤粉和预还原矿喷入铁浴中可产生高质量的煤气和实现预还原矿终还原的目的。本文研究了煤粉在熔铁中热解时，煤粉颗粒的温度分布、气相万分和温度变化，以及煤粉颗粒大小对热解时间的影响；通过观察石墨溶解试样的表面形貌，发现初始表面光滑的石墨在熔铁中溶解后，溶解反应面变为凸凹交错的粗糙面，即真实反应面积大于表观面积，通过引入溶解反应面粗糙度系数和概念，使石墨在熔铁中溶解反应的传质系数得到了较好的修正；实验证实了在铁浴煤氧喷射造气过程中，熔铁内有弥散分布的 FeO 液滴存在，对欠浴煤氧喷射造气机理作出了解释；在对铁浴煤氧（矿）喷射造气与熔融还原过程中的煤粉的热解、溶解、气化反应和预还原铁精矿粉还原动力进行了理论分析的基础上，建立了煤氧矿喷射造气与熔融还原动力学模型。硫磷是生铁中的主要有害元素。根据多相多组分平衡原理，在铁浴－－煤氧喷射气条件下，对硫的走向进行了单元模化，并在 100kg 级热模型上探讨了利用铁浴煤氧（矿）喷射造气与熔融还原设备直接进行脱硫精练，比较了 CaO-CaC_2、CaO-Al_2O_3-CaF_2、CaO-CaF_2、CaO-CaF_2-Al_2O_3、CaO-SiO_2 五种渣的脱硫能力大小和喷粉方式对脱硫速度的影响，建立了渣金反应动力学模型；在 25kg 级感应炉上进行了固体碳还原熔融含磷渣、碳饱和熔铁还原熔融含磷渣、碳饱和熔铁还原熔融预还原矿、CO 气体还原熔融含磷渣的试验，比较了高炉练铁与熔融还原练铁中磷行为的差别，初步揭示了熔融还原过程中磷的物理化学行为。为拓宽熔融还原技术的发展范围，特别是为实现以煤代焦、降低能耗的目的，本论文在铁浴煤氧（矿）喷射造气与熔融还原研究的基础上，探索了磷矿石渣浴煤氧（磷矿）喷射熔融还原练磷（或 P_2O_5）的可能性。论文中分析计算了不同工艺和操作参数条件下的能量消耗；计算机模拟了煤氧在熔盐中燃料廛，煤粉颗粒的温度分布、气相成分和温度变化、气－固－液三相传热等，以及煤粉粒径、煤种、碳氧比、熔池深度等因素对煤粉燃烧的影响；在 25kg 级感应米上分别进行了固体石墨碳、煤粉、铁碳磷饱和熔体、CO 气体还原熔融渣中磷酸盐的试验，并研究了不同还原剂还原熔渣中磷酸盐的反应速度，以及熔渣组成对固体石墨碳还原磷酸盐的影响。
英文摘要	This investigation is focused on coal gasification under the condition of immerged coal-oxygen injection in molten iron or slag bath and on behaviors of sulfur and phosphorus in smelting reduction process. In order to broaden the field of application of smelting reduction, the phosphorus making process was also studied. The coal gasification and final reduction of prereduced iron one can be carried out in the process of coal-oxygen-ore injection into liquid iron bath. In order to describe the mechanics and kinetics of this process, a mathematical model of pyrolysis of coal was established. Based on the experimental result, a model was set up on gasification and smelting reduction of coal-oxygen(-ore) immerged injection process. The calculation and experimental results of gas composition and content of FeO in iron are conformable with the results of pilot scale experiment done by the MEFOS factory in Sweden. Sulfur is one of the harmful elements in iron. In this paper, the behavior of sulfur was studied in the process of gasification. In case of multi-phase and multi-component equilibrium, it was calculated by using the Program Package of Equilibrium Calculation (PPEC). The behavior of phosphorus was also investigated in this paper. In this paper, material consumption was analyzed, the combustion of particle coal in slag melt was modeled, and the experiments were done. The phosphate in molten slag was reduced by graphite, liquid iron saturated with carbon and phosphorus, and CO gas respectively. The energy analysis was made for the system of coal-oxygen injection into the bath of slag with Fe-P alloy. The mathematical model for coal gasification in molten slag combines heat transfer, multi-component equilibrium with the kinetics of pyrolysis and combustion. Degree of combustion, temperature distribution within a particle, temperature and composition of bubbling gas, as well as heat transfer to slag were calculated along the raceway of particle. The results of phosphate reduction in molten slag by graphite show that the temperature and basicity of slag are the most important factors. The higher the basicity (in the range of 0.7～1.5) and temperature, the quicker the reduction rate. But the higher the basicity, the more phosphate retained in slag. The apparent reduction rate constant may be expressed as following for slag basicity CaO/SiO_2 = 1.1 k = 1.1 ·10~3 exp(52000/RT) The result of phosphate reduction by rotating graphite bar shows the reduction rate constant linearly increasing with the square root of rotating rate. The liquid iron saturated with carbon and phosphorus has larger reduction rate than graphite and CO gas.
语种	中文
公开日期	2013-10-31
页码	121
内容类型	学位论文
源URL	[http://ir.ipe.ac.cn/handle/122111/4669]
专题	过程工程研究所_研究所（批量导入）
推荐引用方式 GB/T 7714	郭占成. 铁、磷矿石熔融还原及煤氧浸没喷射气化研究[D]. 北京. 中国科学院研究生院. 1992.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。