Molybdenum Ore Beneficiation Process

The beneficiation method of molybdenum in China is mainly flotation. In the deep beneficiation of molybdenum-dominated ores containing traces of copper, a partially mixed preferential flotation process is used. Jinduicheng molybdenum ore dressing plant processing ore of valuable minerals are molybdenite, pyrite and a small amount of chalcopyrite, the molybdenum-copper mixed flotation, tailings flotation pyrite, copper - molybdenum separation and molybdenum concentrates, part of the mixed-priority flotation process is used. Now, China also recover molybdenum from copper-molybdenum ore beneficiation, commonly used process is copper-molybdenum mixed flotation, and then copper-molybdenum separation and molybdenum concentrate selection.
Molybdenum ore beneficiation processes are: molybdenum beneficiation, copper molybdenum beneficiation, tungsten molybdenum beneficiation and molybdenum bismuth beneficiation to produce molybdenum concentrate.

Commonly used are sodium sulfide method and sodium cyanide method to separate copper and molybdenum and molybdenum concentrate selection. The number of molybdenum concentrates mainly depends on the total enrichment ratio of molybdenum. Generally is the total enrichment ratio is high, then the number of selection is usually more; total enrichment ratio is low, then the number of selection is usually less. Such as Luanchuan molybdenum ore dressing plant processing ore of higher grade (0.2% to 0.3%), enrichment ratio of 133 ~ 155, the original design of the total number of times selected for 7 times, and Jinduicheng a plant to deal with the molybdenum grade of the original ore of about 0.1%, the enrichment ratio of 430 ~ 520, the total number of times selected up to 12 times. In recent years, in order to meet the needs of molybdenum concentrate export, Jinduicheng Molybdenum Ore Dressing Plant adopts hydrochloric acid - ferric chloride leaching method to get rid of impurities in molybdenum concentrate.
Molybdenum ore beneficiation process flow is described:
Firstly, molybdenum ore is crushed by jaw crusher, and then crushed to reasonable fineness by fine jaw crusher, and then sent to silo by elevator.
Secondly, it will be fed into the ball mill by the feeder evenly, and then the ball mill will grind the ore.
Third, after grinding the ore fines into the spiral classifier, spiral classifier with the help of solid particles of different specific gravity, and precipitation in the liquid at different speeds of the principle of washing and grading of the ore mixture.
Fourthly, it is sent to the flotation machine for flotation operation after being stirred by the mixing drum. According to different mineral properties add different corresponding flotation chemicals, flotation machine in the dynamic collision of air bubbles and mineral particles and air bubble particles combined with static separation, so that the required minerals and other substances are separated. Favorable to the separation of fine-grained or micro-fine-grained molybdenum ore.
Fifth, with a high-efficiency concentrator to remove the water in the mineral concentrate after flotation, up to the national standard.
From China's non-ferrous system of some molybdenum ore beneficiation plant, the grade of the raw ore handled varies greatly, high in more than 0.3%, low in less than 0.1%, some only 0.02%. The actual recovery rate through the molybdenum ore beneficiation plant is overwhelmingly above 80%. The obtained concentrate grade in 45% ~ 54%, tailings grade more in 0.02% or so, high in 0.04%, low in 0.01%.
In the current industrial production of molybdenum, molybdenum ore beneficiation equipment process is mainly used for smelting of molybdenum pyroxene concentrate, there are three links of oxidative roasting, extraction of pure molybdenum trioxide, and reduction roasting into metal molybdenum powder.
Molybdenum concentrate is first oxidized and roasted in reflector furnace, multi-chamber furnace, boiling furnace, or flash furnace, after desulfurization, it is made into a kind of impure molybdenum trioxide (40% to 48%) of roasted sand, and roasted sand can produce molybdenum ferroalloys by using metal-heat method or silica-heat method. There are two methods to produce pure molybdenum trioxide from the roasted sand: one is the sublimation method, and the other is the hydrometallurgical method. With ammonia solution leaching, purification to remove impurities, followed by crystallization or hydrochloric acid neutralization method so that the molybdenum into ammonium molybdate (56%) or molybdate state precipitation, and then by roasting into pure molybdenum trioxide. Finally, pure molybdenum trioxide is made into metal molybdenum powder (99.7%~99.9%) by hydrogen reduction method, and then molybdenum ingot or molybdenum strip by powder metallurgy method or further by arc melting method.
At present, domestic and foreign molybdenum concentrate smelting process also studied and tested a number of new technologies and methods, such as molybdenum pyroxene concentrate without oxidizing roasting, directly with oxygen pressure cooking method or bacterial leaching method to extract pure molybdenum trioxide. For low-grade oxidized ore leaching with sulfuric acid, from the solution with ion exchange method or extraction method to extract pure molybdenum trioxide. In addition, molybdenum concentrate smelting methods, there are lime roasting method, nitric acid leaching method, sodium hypochlorite leaching method, electro-oxidative leaching method.
Rhenium in molybdenum concentrate, mainly from the molybdenum concentrate oxidation roasting flue gas washout or oxygen pressure cooking liquid recovery, and then from the solution using extraction or ion exchange into potassium perrhenate or ammonium perrhenate, and then made of high-purity rhenium powder by the reduction method.
Molybdenum concentrate in the harmful impurities, such as copper, lead, tin, arsenic, phosphorus, calcium, silica, etc., not only affect the quality of molybdenum products, but also affect the molybdenum smelting process and equipment, and pollution of the environment. They need to be strictly controlled before smelting or recovered in smelting, thus becoming useful components and greatly improving the industrial value of molybdenum deposits.