Molybdenum ore dressing process

Single molybdenite beneficiation method

The typical beneficiation method of single molybdenum ore is to make full use of the natural floatability of molybdenite, first rough grinding and rough selection, and then re-grinding and re-selection process. Practice has shown that under high distillation range and wide distillation point hydrocarbon oil, 1/17-1/23 of molybdenite intergrowth can float well. In the flotation process, since the molybdenum content of molybdenite is very low, this requires high molybdenum precision, so it needs to be finely concentrated several times (generally 5-10 times) to make the molybdenum ore enrichment ratio high.

In addition, since molybdenite itself is relatively soft, it is easy to be muddy during the fine grinding process, which has a significant impact on the precision of molybdenum ore. In the beneficiation process, according to the natural floatability of molybdenite, the intergrowth produced by rough grinding can be finely ground several times, so that the intergrowth can be fully dissociated and then finely selected.

1. Copper-molybdenum ore dressing method

Molybdenum recovery from copper-molybdenum ore is also the main source of molybdenum resources. Copper-molybdenum ore has good natural floatability, fine embedded particle size, low ore grade, and high symbiosis with pyrite and chalcopyrite. It is relatively more difficult to recover molybdenum ore and the process is more complicated.

Common beneficiation methods mainly include preferential flotation and mixed flotation. Among them, the mixed flotation method is more widely used. First, the copper-molybdenum rough concentrate is selected by rough selection, and then the copper and molybdenum elements are separated from the obtained rough concentrate. Since molybdenite and sulfide ore are both easy to float, it is also relatively easy to obtain copper-molybdenum concentrate. However, in order to achieve copper-molybdenum separation in copper-molybdenum ore, some separation methods are still needed:

Conventional flotation method:In order to obtain molybdenum, the floating of copper minerals must be suppressed. Conventional flotation usually uses aluminum flotation to suppress copper. There are two main types of agents currently used to suppress copper ore, one is organic agents, such as ethyl mercaptan; the other is inorganic agents, such as cyanide, sodium sulfide, etc. Adding agents during flotation can suppress copper. In order to enhance the flotation of molybdenum minerals, a small dose of non-polar oil can also be added, such as adding water glass and other adjusting agents to suppress the dispersed slurry and gangue minerals, which can improve the grade of molybdenum concentrate. After several rounds of selection, high-quality molybdenum concentrate can be obtained.

Nitrogen filling flotation method: At present, people's environmental protection awareness is deepening, and they pay more attention to the ecological environment and social environment. The use of cyanide copper inhibitors will cause certain pollution to the environment, so most molybdenum ore dressing plants currently use sodium hydrosulfide or sodium sulfide as copper inhibitors. However, sodium sulfide has a strong reducing property and will be easily oxidized by dissolved oxygen in the ore pulp during flotation. The amount of reagents used in actual practical use is also large. The use of nitrogen flotation can effectively control the use of inhibitors.

Pulsating high gradient magnetic separation: is an effective method for separating fine-grained minerals with weak magnetism. It is widely used in the separation of manganese ore, weak magnetite and other minerals. The high gradient magnetic separator has a high-frequency vibration mechanism, adopts recoil concentrate and rotating ring vertical rotation technology, and separates and removes non-magnetic minerals mixed in the ore through the action of the magnetic field, and absorbs the concentrate on the surface of the cylinder in the form of magnetic chains or magnetic clusters, and is gradually transmitted to the edge of the magnetic system. Under the action of flushing water, the concentrate is unloaded into the concentrate tank. Molybdenite is a non-magnetic mineral, so this method cannot be used. However, copper-molybdenum ore has weak magnetism, so this method can be used to separate copper and molybdenum.

Method for beneficiation of molybdenum-containing polymetallic ores

For quartz vein gold, molybdenum, lead and sulfur polymetallic ores, flotation can be used to produce mixed rough concentrates, and then the rough concentrates are cyanide leached to recover gold, and then the leached tailings are subjected to molybdenum separation and flotation to produce molybdenum concentrates, and the tailings of the flotation molybdenum concentrates are separated from lead and sulfur to produce lead concentrates and sulfur concentrates.

For low-grade tungsten, molybdenum and bismuth ores, the process flow of molybdenum-bismuth mixed selection and separation can be adopted. After the mixed rough concentrates are obtained by molybdenum-bismuth mixed rough selection, molybdenum-bismuth-sulfur separation and molybdenum-bismuth separation are carried out.