难选铁矿石磁化焙烧变径回转窑设备研究

发布时间：2018-05-25 11:07

本文选题：回转窑 + 窑体结圈　；参考：《兰州理工大学》2017年硕士论文

【摘要】：近几年,钢铁行业处于微利或亏损经营状况,不少企业面临生死存亡考验,唯一求得生存的途径就是通过技术创新降低成本,而提高自产铁矿石利用率是有效降低成本一条途径。目前,国内数十亿吨难选铁矿石,受磁化焙烧工艺装备限制,不能有效利用,迫切需要开发出适合国内难选铁矿石磁化焙烧处理的回转窑装置。本课题主要以回转窑磁化焙烧装置为研究对象,对窑体结圈的机理进行研究分析,研究通过改变窑体结构抑制结圈的可行性,根据烟气流动过程中质量守恒原理和物料入窑预热、干燥、加热、还原所需时间及窑体长度,确定回转窑窑体结构设计的半径比和长径比,对实验室难选铁矿磁化焙烧回转窑窑体结构参数进行优化设计;开展变径回转窑和通径回转窑磁化焙烧处理酒钢0~15mm铁矿石分级后的1~5mm粒级粉矿窑体结圈对比验证试验,验证窑体变径优化设计对处理难选铁矿石抑制结圈的效果,根据试验结果,对已投用产业化生产的回转窑窑体结构进行设计。首先,对回转窑磁化焙烧难选铁矿石结圈机理进行分析研究,主要对窑体结圈的位置、窑体固相和液相结圈的机理及窑体结圈的影响因素进行分析,提出细粒级低熔点物质入窑和回转窑窑内局部高温是造成窑内结圈主要原因的观点。防止细粒级物料入窑可采用粒度分级的方法解决,而窑体内局部高温需通过窑体结构优化设计来解决,根据烟气流动过程中质量守恒原理和物料入窑预热、干燥、加热、还原所需时间及窑体长度,确定回转窑窑体结构设计的半径比为(?)倍和长径比为13~17倍以及回转窑窑体传动装置的参数设计。对实验室φ0.45×6m燃气通径回转窑进行窑体结构变径优化设计。其次,采用φ0.65~0.45×9m燃气变径回转窑和φ0.45×6m燃气通径回转窑,对酒钢镜铁矿1~5mm粒级粉矿进行磁化焙烧窑体结圈验证试验。验证试验结果显示,在磁化焙烧温度等其它参数相同条件下,变径回转窑较通径回转窑产能提高了50%、能耗降低20%左右,且具有明显抑制结圈功能,并对三种已投入产业化生产的回转窑进行窑体结构设计,确定了回转窑技术参数和运行参数。该项目完成后,能够有效解决回转窑受窑体结圈制约,不能广泛应用于难选铁矿石磁化焙烧领域的问题,为国内数十亿吨难选铁矿石有效利用提供高产能、低能耗的磁化焙烧装备,市场前景广阔。
[Abstract]:In recent years, the iron and steel industry has been in a state of little profit or loss, and many enterprises are facing the test of survival and death. The only way to survive is to reduce costs through technological innovation. Raising the utilization rate of self-produced iron ore is an effective way to reduce cost. At present, billions of tons of refractory iron ore in China are limited by magnetization roasting technology and equipment, so it is urgent to develop a rotary kiln which is suitable for magnetization roasting treatment of refractory iron ore in China. This topic mainly takes the rotary kiln magnetization roasting device as the research object, carries on the research analysis to the kiln body junction ring mechanism, studies through changing the kiln body structure to suppress the junction ring feasibility, According to the principle of mass conservation in the process of flue gas flow, the time required to preheat, drying, heating and reducing materials into kiln and the length of kiln body, the radius ratio and aspect ratio of structure design of rotary kiln are determined. The structure parameters of magnetized roasting rotary kiln with refractory iron ore in laboratory were optimized, and the comparative verification test of 1~5mm granular-grade powder kiln after magnetized roasting treatment of 0~15mm iron ore in Jiugang was carried out in variable diameter rotary kiln and through diameter rotary kiln. It is verified that the optimum design of kiln body diameter is effective in treating refractory iron ore. According to the test results, the structure of rotary kiln which has been put into industrial production has been designed. Firstly, the mechanism of refractory iron ore ring formation in rotary kiln magnetization roasting is analyzed. The position of kiln body ring, the mechanism of kiln solid and liquid phase ring formation and the influence factors of kiln body ring formation are analyzed. It is pointed out that the local high temperature in the kiln with fine grain and low melting point is the main reason for the formation of the ring in the kiln. The method of granularity classification can be used to prevent fine grained material from entering into kiln, and the local high temperature of kiln needs to be solved by optimizing design of kiln structure. According to the principle of conservation of mass in flue gas flow and the preheating, drying and heating of material into kiln, The reduction time and kiln length are determined to determine the radius ratio of the structure design of rotary kiln. The ratio of length to diameter is 1317 times and the parameter design of rotary kiln. The optimization design of the kiln structure for the rotary kiln with gas diameter of 0.45 脳 6 m in laboratory is carried out. Secondly, using 蠁 0.65 ~ 0.45 脳 9 m gas variable diameter rotary kiln and 蠁 0.45 脳 6 m gas path rotary kiln, the magnetization roasting kiln of 1~5mm granulated powder ore in Jiugang was tested. The experimental results show that under the same conditions of magnetization calcination temperature and other parameters, the productivity of variable diameter rotary kiln is increased by 50%, the energy consumption is reduced by about 20%, and the loop forming function is obviously inhibited. The structure of three rotary kilns which have been put into industrial production has been designed and the technical parameters and operation parameters of rotary kilns have been determined. After the completion of the project, it can effectively solve the problem that the rotary kiln is restricted by the kiln body and can not be widely used in the field of magnetization roasting of refractory iron ore, and can provide high production capacity for the effective utilization of billions of tons of refractory iron ore in China. The low energy consumption magnetization roasting equipment has a broad market prospect.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD951

【参考文献】