Molybdenum beneficiation of half a century of history, molybdenum processing plant developed from an old Chinese only Yangjiazhangzi molybdenum processing plant now has more than 50 molybdenum processing plant, copper processing plant molybdenum, tungsten, molybdenum, bismuth and molybdenum processing plant selected The factory produces molybdenum concentrate. The gap between molybdenum beneficiation technology and advanced foreign countries has become smaller and smaller. Wire Mesh,Metal Mesh,Chicken Wire Fence,Chicken Wire Mesh Anping Guangtong Hardware Wire Mesh Co.,Ltd , https://www.gt-meshfilter.com
The method of mineral processing of molybdenum in China is mainly flotation. In the deep selection of molybdenum-based ores containing trace amounts of copper, a partial mixing-priority flotation process was employed. Valuable mineral ore dressing plant Jinduicheng Molybdenum process is molybdenite, pyrite and minor chalcopyrite, using a molybdenum-copper flotation, flotation pyrite tailings, copper - molybdenum and molybdenum separation Partial blending of concentrates - priority flotation process. At present, China also recovers molybdenum from copper molybdenum ore. The common process is copper-molybdenum mixed flotation, and then copper-molybdenum separation and molybdenum concentrate.
The selection of copper-molybdenum separation and molybdenum concentrate is mainly carried out by sodium sulfide method and sodium cyanide method. The number of molybdenum picks depends primarily on the total enrichment ratio of molybdenum. Generally, the total enrichment ratio is high, and the number of selections is usually more; the total enrichment ratio is lower, and the number of selections is usually less. For example, the ore grade of the ore processed by Luanchuan Molybdenum Plant is higher (0.2%-0.3%), the enrichment ratio is 133-155, and the total number of selected original designs is 7 times, while Jinduicheng No.1 Plant The treated ore has a molybdenum grade of about 0.1%, an enrichment ratio of 430 to 520, and a total number of selections of 12 times. In recent years, in order to meet the needs of molybdenum concentrate export, Jinduicheng Molybdenum Separation Plant uses hydrochloric acid-ferric chloride leaching method to remove impurities in molybdenum concentrate.
From the perspective of some molybdenum plants in China's non-ferrous systems, the treated ore grades vary greatly, with highs above 0.3%, lows below 0.1%, and some only 0.02%. The actual recovery rate of mineral processing is over 80%. The refined concentrate grade is between 45% and 54%, the tailings grade is about 0.02%, the high is 0.04%, and the low is 0.01%.
In the current industrial production of molybdenum, mainly using molybdenite concentrate for smelting, there are three links of oxidative roasting, extraction of pure molybdenum trioxide, reduction roasting into metal molybdenum powder.
The molybdenum concentrate is first oxidized and roasted in a reverberatory furnace, a multi-hearth furnace, a boiling furnace, or a flash furnace, and is desulfurized to form an impure molybdenum trioxide (Mo ≥ 40% to 48%) of calcined sand. A ferromolybdenum alloy can be produced by a metal thermal method or a silicon thermal method. There are two methods for producing pure molybdenum trioxide from calcination: one is sublimation and the other is hydrometallurgy. The impurities are leached and purified by ammonia solution, and then the molybdenum is precipitated into ammonium paramolybdate (Mo ≥ 56%) or molybdic acid by crystallization or hydrochloric acid neutralization, and then purified to form pure molybdenum trioxide. Finally, the pure molybdenum trioxide is made into metal molybdenum powder by hydrogen reduction method (Mo≥99.7%～99.9%), and then molybdenum ingot or molybdenum strip is prepared by powder metallurgy or further by arc melting method (Mo≥99.8%～99.95%) .
At present, some new technologies and methods have been studied for the smelting of molybdenum concentrates at home and abroad. For example, molybdenite concentrates are directly oxidized and calcined, and pure molybdenum trioxide is directly extracted by oxygen pressing or bacterial leaching. The low-grade oxidation ore is leached with sulfuric acid, and pure molybdenum trioxide is extracted from the solution by ion exchange or extraction. In addition, the smelting method of the molybdenum concentrate includes a lime roasting method, a nitric acid leaching method, a sodium hypochlorite leaching method, an electrooxidation leaching method, and the like.
Molybdenum concentrate rhenium, roasting fumes from the primary molybdenum concentrate leaching solution or oxygen pressure cooking liquor for recovery, and then extracted with a solution from a method or an ion exchange method as potassium perrhenate or ammonium perrhenate And then use the reduction method to make high-purity glutinous powder.
Harmful impurities in molybdenum concentrates, such as copper, lead , tin , arsenic , phosphorus , calcium, silica, etc., not only affect the quality of molybdenum products, but also affect the process and equipment of molybdenum smelting, and pollute the environment. It must be strictly controlled before smelting, or recycled in smelting, thus becoming a useful component and greatly increasing the industrial value of molybdenum deposits.