螺磁机的研制及其在攀枝花磁选厂的选矿试验研究

【作者】 郭学君；

【导师】 文书明；

【作者基本信息】 昆明理工大学 ， 矿物加工工程， 2004， 硕士

【摘要】 新型高效磁铁矿精选设备的研制一直是选矿界的难点之一。自八十年代以来，随着矿产资源的日益贫化以及人类对钢铁需求量的不断扩大，加之环保要求，人们对高炉冶炼入炉的铁精矿品位要求越来越高，由于磁选能耗低，不需要价格昂贵的药剂，一大批新型磁选设备相继问世。攀枝花钒钛磁铁矿的磁选，已有30多年的历史，经过大量的试验研究与生产实践，磁选机筒体直径从φ750mm发展到φ1050mm，减少了磁选机的台数，显著地提高了选别作业的技术水平。然而随着市场经济的发展和产品竞争的不断升级，冶炼厂对钒钛铁精矿品位的要求，已从20世纪90年代的51.5％提升到目前的52.6％，这对选矿厂的生产产生了极大的压力。为了满足这一精矿指标的要求，选矿厂做了大量的技术工作，然而只有细磨是最有效的。通过细磨不仅可以使精矿品提升到52.6％以上，而且还有继续提升到53％的可能。但代价是巨大的，即细磨大大地降低了磨机的处理能力，选矿成本升高，同时矿石磨细后，-0.045mm粒级含量大幅度增加，粗选回收率显著下降，严重地影响了企业的经济效益和资源综合回收率。因此研究开发新型高效磁铁矿精选设备已迫在眉睫，本论文选择新型高效磁铁矿精选设备—螺磁机的研制及试验作为硕士论文的研究内容。 我们在认真分析和研究现有磁选设备的基础上，针对攀钢选厂原矿入选粒度偏粗，有用矿物钛磁铁矿中，钛铁共生为复合矿物相，单一靠磁选的方法难以明显提高其精矿品位的特点，认为利用磁重联合力场，同时加强磁场强度和加强水力的淘洗冲刷作用，有利于磁铁矿精选。以开放磁系理论为基础，结合磁团聚弱磁选理论，提出了一种全新的磁铁矿精选设备—螺磁机的设计思想，突破了传统的“提高铁精矿品位就必须降低磁场强度”的观点。对螺磁机工业样机的设计提出了如下的要求：①螺磁机的磁系使用带有四条螺旋形的开放型磁系；②分选空间必须选用不导磁的耐磨损材料；③加强磁场强度以增加对磁性矿物的回收和加强切向给入的上升水流的强度以加强对非磁性矿物的淘洗，提高精矿品位；④整台样机需运行稳定可靠，调整方便，布局合理。 螺磁机主要由旋转螺旋磁系、环形分选柱、给矿匀分器、尾矿槽、机架、精矿槽、传动系统等组成。具有分选精度高，精矿品位高，精矿回收率高以及能适用于强磁性矿物的粗选、精选和扫选的特点。 螺磁机用于选别攀枝花帆钦磁铁矿的最佳操作条件为给矿ts吨/小时、磁系转速30转/分、单元格上升水t250奄升/秒.其选别指标为:铁精矿品位53.69%，尾矿品位15.87%，回收率为97.48%. 理论研究表明:攀枝花钒钦磁铁矿现用中1050x3000mm湿式永磁筒式磁选机的磁场特性为H。·131.77‘，，J锄.0.125mm粗粒钦磁铁矿在中1050x300omm磁选机中距简体表面70.28mm处所受的磁力与机械总力平衡，该磁选机在底箱间隙小于7o.28mm时，适合于该粒级钦磁铁矿的磁选.而0.045mm粒级钦磁铁矿在距筒体表面75mm时，所受的机械总力是磁力的10倍，处于该位哭的0.045mm单颗粒钦磁铁矿磁选回收困难.因此要提高0.045mm细粒和徽细粒级钦磁铁矿的回收率，改变磁选机的磁场特性是必要的.扮咋螺磁机的上升水速应满足v>耐科(‘，一p)s 句脚其磁场强度应满足HgradH，竺兰巡色匕边叼碑川JZ磁系转速要求。.嘴李 h-科屏心阴以衬 甸姆h.处理能.~、，~，、~、:_龙D刀明甘异公双刀:9.二万q。 JU同常规的湿式永磁筒式弱磁场徽选机相比，螺徽机的精选能力有了极大的提高。更多还原

【Abstract】 It has always been the difficulties to develop a new type of efficient equipment for cleaning magnetite in the mill. Since the 1980s, because of the indigence of mineral resources, the ever-increasing need for the steel, and protecting the environment, we need better quality of iron concentrate and the lowness of the energy consumption and chemical regents, a new set of equipment of magnetic separation appeared. Panzhihua vanadium titanium magnetite separation has a history of about 30 years. Magnetism separator has developed from 750mm to 1050mm; there is a reduction in the number of machines and operations technical level is obviously increased. However, with the development of market economy and the upgrade of the product competition, the smelt factory calls for the high grade of vanadium titanium concentrate, the grade has risen to 52.6% from 51.5% in the 1980s, which has led to the much pressure for the smelt factory. In order to meet the needs of this index, the factory has done a lot of technical work, but only fine grinding is most efficient. The concentrate grade not only rises to 52.6% but also rises to 53% through the fine grinding. But the cost is high, the fine grinding decreases the machine processing capacity, makes the cost increase, at the same time the contain of the -0.045mm particles increases largely, the recovery decreases apparently, which seriously affects the economic profits and the recovery of the resources. It is urgent to develop a new type of equipment, so the thesis focuses on the study of the new type efficient magnetic iron ore separation equipment ?spiral magnetic separation machine.We have analyzed and studied the present magnetic separators carefully, the results show that the Pangang raw mineral particle size is a little big, vanadium titano-magnetite is complex mineral combination available, it is difficult to promote the concentrate grade by a single separate method. So we consider definitely to make use of magnetic-gravity and to strengthen magnetic intensity and water. We have done much to design of the magnetic system and introduced a new designation of the spiral magnetic system firstly. It is based on the theory of the open magnetic system and the low magnetic coagulation theory; we put forward a new designation conception about spiral magnetic separator. It breaks down the traditional opinions-must be decreased magnetic intensity to improve Fe concentrate grade. It is required that the need of the designation of industrial prototype: 甌he designation of the four spiral magnetic is an important basis to realize the theory. (2) In order to realize the theory, the separation space must be un-conducted magnetic materials. (3) The water and the magnetic must be improved and strengthen, so that the recovery of the magnetic mineral and the Fe concentrate grade is improved. (4) The prototype must run steadily, be adjusted conveniently and layout reasonably.The spiral magnetic separator is made up of revolving spiral magnetic system, loop separation tube, presenting ore even disport organ, trailing groove, frame, concentrate groove, drive system. This machine has the characteristics of high separation precision, grade andrecovery and can be used in the coarse separation, fine separation and scavenging of the strong magnetic minerals.The optimal operation conditions of the spiral magnetic separator in Panzhihua are as follows: feed rate is 5t/h, rotation speed is 30r/h, and ascending water is 250ml/s. The index is follow: iron concentrate grade is 53.69%, tailing grade is 15.87%, and the recovery is 97.48%.According to the theory and research, magnetism characteristic of the wet permanent magnetic tube separator is . The magnetic force acting on the 0.125mm coarse particles titanium magnetite iron, which is 70.28mm from tube surface in the diameter 1050x3000mm separator, is balanced with mechanic resultant force. If the bottom separation space is less than 70.28mm in the machine, it adapts to the recover of the titanium magnetite. However, when the 0.045mm titanium magn更多还原