阅读说明：本技术 一种高纯氧化钼的制备方法及装备 (Preparation method and equipment of high-purity molybdenum oxide ) 是由 陈慧 梁博 于 2020-03-31 设计创作，主要内容包括：本发明公开了一种高纯氧化钼的制备方法及装备,包括球磨、预热干燥、氧化焙烧、升华以及冷凝过程,以钼精矿为原料,其中,原料经过球磨后钼精矿的粒度范围为50～300目之间,预热干燥过程中的温度范围为100～350℃；氧化焙烧过程中氧化焙烧的温度范围为450～680℃,空气的气速为0.8～15m/s,氧化焙烧过程在沸腾炉中进行；升华过程中的保持温度范围为650～1050℃；冷凝过程中的冷凝温度范围为20～250℃；一种高纯氧化钼的制备装备,包括：原料料斗、风机、预热干燥装置、沸腾炉、炉渣槽、废气处理设备、升华炉、冷凝沉降室、成品槽以及废气室。本发明的制备方法和制备装备实现了高精度的制备高纯氧化钼,而且具有工艺流程短、制备方法简单以及生产效率高的特点。(The invention discloses a preparation method and equipment of high-purity molybdenum oxide, which comprises the processes of ball milling, preheating and drying, oxidizing and roasting, subliming and condensing, wherein molybdenum concentrate is taken as a raw material, the granularity range of the molybdenum concentrate after ball milling of the raw material is 50-300 meshes, and the temperature range in the preheating and drying process is 100-350 ℃; the temperature range of oxidizing roasting in the oxidizing roasting process is 450-680 ℃, the air speed of air is 0.8-15 m/s, and the oxidizing roasting process is carried out in a fluidized bed furnace; the temperature range of the sublimation process is 650-1050 ℃; the condensation temperature range in the condensation process is 20-250 ℃; a preparation device of high-purity molybdenum oxide comprises: raw materials hopper, fan, preheating drying device, fluidized bed furnace, slag groove, exhaust-gas treatment equipment, sublimation furnace, condensation settling chamber, finished product groove and exhaust-gas chamber. The preparation method and the preparation equipment of the invention realize the high-precision preparation of the high-purity molybdenum oxide, and have the characteristics of short process flow, simple preparation method and high production efficiency.)

1. A preparation method of high-purity molybdenum oxide takes molybdenum concentrate as a raw material, and is characterized in that: the method specifically comprises the following steps:

s110, crushing and ball-milling the molybdenum concentrate to obtain molybdenum concentrate powder, wherein the granularity of the molybdenum concentrate powder is 50-300 meshes;

s120, carrying out preheating and drying treatment on the molybdenum concentrate powder to remove oil and water in the molybdenum concentrate powder, wherein the temperature range of preheating and drying is 100-350 ℃;

s130, placing the preheated and dried molybdenum concentrate powder in molybdenum concentrate preparation equipment for oxidation roasting reaction, wherein the temperature range of the oxidation roasting reaction is 450-680 ℃, and continuously introducing air into the equipment, wherein the air velocity of the introduced air is 0.8-15 m/S;

s140, sublimating the molybdenum calcine, wherein the product obtained after the oxidizing roasting reaction is the molybdenum calcine, and the sublimating temperature is 650-1050 ℃;

s150, condensing the molybdenum calcine, wherein the temperature range of condensation is 20-250 ℃.

2. The method for preparing high-purity molybdenum oxide according to claim 1, wherein: the particle size of the molybdenum concentrate powder is less than 50 meshes.

3. The method for preparing high-purity molybdenum oxide according to claim 1, wherein: the preheating and drying temperature is more than 100 ℃, and the preheating time is more than 5 seconds.

4. The method for preparing high-purity molybdenum oxide according to claim 1, wherein: the temperature range of the oxidizing roasting is 450-680 ℃, the retention time is more than 5 seconds, and the gas velocity is kept at 0.9-1.1 m/s.

5. The method for preparing high-purity molybdenum oxide according to claim 1, wherein: the sublimation temperature range is 650-1050 ℃.

6. The method for preparing high-purity molybdenum oxide according to claim 1, wherein: the preparation equipment should be kept in a continuous boiling state in the oxidizing roasting reaction.

7. A preparation equipment of high-purity molybdenum oxide is characterized in that: the method comprises the following steps: the system comprises a raw material hopper, a fan, a preheating and drying device, a fluidized bed furnace, a slag groove, waste gas treatment equipment, a sublimation furnace, a condensation settling chamber, a finished product groove and a waste gas chamber, wherein an outlet of the raw material hopper is connected with an inlet of the preheating and drying device, an outlet of the preheating device is connected with the fluidized bed furnace, a bottom outlet of the fluidized bed furnace is connected with the slag groove, a middle reaction product outlet of the fluidized bed furnace is connected with the sublimation furnace, an outlet of the sublimation furnace is connected with the condensation settling chamber, a product outlet of the condensation settling chamber is connected with the finished product groove, the bottom of the sublimation furnace is connected with the slag groove, the top of the fluidized bed furnace is connected with the waste gas treatment equipment, and the middle of the condensation settling chamber and the waste gas treatment equipment are both connected with the waste gas chamber;

the fluidized bed furnace also comprises a heating pipeline and a waste heat recovery device, the waste heat recovery device is simultaneously connected with the preheating drying device and the sublimation furnace, and the waste heat recovery device is used for recovering waste heat in the heating pipeline; the fan is connected with the fluidized bed furnace and used for introducing air with a certain air speed into the fluidized bed furnace; and a transpiration device and a stirring device are arranged in the sublimation furnace.

8. The equipment for preparing high-purity molybdenum oxide according to claim 7, wherein: the sublimation furnace is cooled by air refrigeration, liquid nitrogen, water cooling and the like.

9. The equipment for preparing high-purity molybdenum oxide according to claim 7, wherein: the section of the transpiration device comprises any one of an isosceles triangle, a trapezoid and an arc.

Technical Field

The invention relates to the field of tungsten-molybdenum metallurgy metals in nonferrous metallurgy industry, in particular to a preparation method and equipment of high-purity molybdenum oxide.

Background

The high-purity molybdenum trioxide is that the MoO3 content is 99.8% -99.99%, and it is the basic raw material for preparing metal molybdenum powder, also can be used as raw material of high-purity reagent. The raw material for producing the high-purity molybdenum trioxide is molybdenum calcine, namely industrial molybdenum trioxide powder.

The production of high-purity molybdenum trioxide powder from molybdenum calcine has two completely opposite process roads: the first method is a wet method, the method purifies and purifies molybdenum calcine by the wet method to generate ammonium paramolybdate powder, and the ammonium paramolybdate is heated and dissociated to expel clean gas to obtain high-purity molybdenum trioxide; the second method is a pyrogenic process, in which the roasted molybdenum sand is directly heated, so that the impurities in the roasted molybdenum sand remain in the roasted slag, and most of molybdenum trioxide is purified and recrystallized to produce high-purity molybdenum trioxide powder.

The current mainstream method for producing high-purity molybdenum oxide in China is a wet method, but the current process has the following obvious defects and is long in process, and molybdenum loss can be caused in the working procedures of molybdenum calcine production, calcine leaching, ammonium paramolybdate pyrolysis and the like; the hazardous chemicals in the process are various and have great harm to the environment.

Disclosure of Invention

Aiming at the problems of long process for preparing the high-purity molybdenum oxide, more molybdenum loss in the process and more dangerous products in the process so as to influence the environmental safety, the invention provides the preparation method and equipment of the high-purity molybdenum oxide, which adopt continuous feeding and sectional preparation processes, thereby simplifying the preparation process and improving the product quality and the production efficiency; the environmental protection is realized by intensively collecting the reaction waste gas and optimizing the treatment of the reaction residues.

In order to achieve the technical purpose, the technical scheme provided by the invention is as follows:

a preparation method of high-purity molybdenum oxide takes molybdenum concentrate as a raw material, and specifically comprises the following steps:

s110, crushing and ball-milling the molybdenum concentrate to obtain molybdenum concentrate powder, wherein the granularity of the molybdenum concentrate powder is 50-300 meshes;

s120, carrying out preheating and drying treatment on the molybdenum concentrate powder to remove oil and water in the molybdenum concentrate powder, wherein the temperature range of preheating and drying is 100-350 ℃;

s130, placing the preheated and dried molybdenum concentrate powder in molybdenum concentrate preparation equipment for oxidation roasting reaction, wherein the temperature range of the oxidation roasting reaction is 450-680 ℃, and continuously introducing air into the equipment, wherein the air velocity of the introduced air is 0.8-15 m/S;

s140, sublimating the molybdenum calcine, wherein the product obtained after the oxidizing roasting reaction is the molybdenum calcine, and the sublimating temperature is 650-1050 ℃;

s150, condensing the molybdenum calcine, wherein the temperature range of condensation is 20-250 ℃.

Preferably, the particle size of the molybdenum concentrate powder is less than 200 mesh.

By adopting the technical scheme, the smaller the mesh number of the molybdenum concentrate powder is, the better the drying effect in the primary preheating and drying process is, and the faster the corresponding drying speed is.

Preferably, the preheating drying temperature is more than 320 ℃, and the preheating time is more than 5 seconds.

By adopting the technical scheme, the preheating effect of the molybdenum concentrate powder is ensured to be more perfect on the premise of protecting the chemical property of the molybdenum concentrate powder.

Preferably, the temperature range of the oxidizing roasting is 550-650 ℃, the retention time is more than 5 minutes, and the gas velocity is kept at 0.9-1.1 m/s.

By adopting the technical scheme, in the oxidation reaction process, the reaction temperature is in direct proportion to the reaction speed, namely the higher the temperature is, the faster the reaction speed is; the smaller the temperature range of high temperature, the more stable the reaction process and the less by-products of the reaction.

Preferably, the sublimation temperature range is 950-1050 ℃.

By adopting the technical scheme, the sublimation process is higher in sublimation temperature and faster in sublimation speed, the chemical performance of the high-purity molybdenum oxide is ensured to be complete under the premise of guaranteeing high-efficiency sublimation of the temperature interval, and the generation of other byproducts is reduced.

Preferably, the preparation equipment in the oxidizing roasting reaction is kept in a continuous boiling state.

By adopting the technical scheme, the sintering of the molybdenum concentrate and the generation of molybdate can be reduced by keeping the continuous boiling state, so that the oxidation reaction is more thorough, and the reaction precision is improved.

Compared with the prior art, the invention has the beneficial effects that: the process is simple, the loss of molybdenum in the process is less, and the preparation precision of the high-purity molybdenum oxide is high.

The invention also provides preparation equipment of the high-purity molybdenum oxide, which comprises the following components: the device comprises a raw material hopper, a fan, a preheating and drying device, a fluidized bed furnace, a slag groove, waste gas treatment equipment, a sublimation furnace, a condensation settling chamber, a finished product groove and a waste gas chamber, wherein an outlet of the raw material hopper is connected with an inlet of the preheating and drying device; the fluidized bed furnace also comprises a heating pipeline and a waste heat recovery device, the waste heat recovery device is simultaneously connected with the preheating drying device and the sublimation furnace, and the waste heat recovery device is used for recovering waste heat in the heating pipeline; the fan is connected with the fluidized bed furnace and used for introducing air with a certain air speed into the fluidized bed furnace; the sublimation furnace is internally provided with a transpiration device and a stirring device.

In the preparation equipment of the molybdenum oxide, the collection equipment of waste gas and waste residue is added, the collected waste gas is introduced into a waste gas chamber, and the waste gas is further treated and decomposed by the waste gas chamber, so that the discharged waste gas reaches the emission standard required by the environment; the slag in the slag groove comprises a mixture of silicon dioxide and other metal oxides which are byproducts of the reaction, and the byproducts are collected and transferred to a smelting unit for further comprehensive utilization.

Preferably, the sublimation furnace is cooled by air refrigeration.

By adopting the technical scheme, the flow velocity of air in the sublimation process is controlled by the fan, so that the control is convenient, the operation is convenient, and the production cost is low.

Preferably, the cross section of the transpiration device comprises any one of an isosceles triangle, a trapezoid and a circular arc.

By adopting the technical scheme, the transpiration device in the form of isosceles triangle, trapezoid and arc increases the transpiration area in the sublimation furnace, accelerates the sublimation process of molybdenum trioxide, and reduces the generation of molybdate.

Compared with the prior art, the preparation equipment of the high-purity molybdenum oxide provided by the invention realizes the preparation of the high-purity molybdenum oxide with the purity of 99.9%, comprehensively simplifies the preparation process of the molybdenum oxide, reduces the loss of molybdenum in the preparation process, simultaneously reduces the discharge of dangerous substances, and protects the safety of ecological environment.

The beneficial effects of the invention are that:

the raw material molybdenum concentrate is preheated and dried in a preheating and drying device, water and oil in the molybdenum concentrate are removed, the preheated and dried molybdenum concentrate is put into a fluidized bed furnace for oxidation roasting reaction, desulfurization is realized, relatively pure molybdenum trioxide is produced, and then sublimation and condensation post-treatment are carried out on the relatively pure molybdenum trioxide after oxidation desulfurization, so that high-purity molybdenum trioxide is obtained. The preparation method and the preparation equipment realize high-precision preparation of high-purity molybdenum oxide, and have the characteristics of short process flow, simple preparation method and high production efficiency.

Drawings

FIG. 1 is a flow chart of a preparation method for preparing high-purity molybdenum oxide according to an example;

FIG. 2 is a schematic view of a production equipment for producing high purity molybdenum oxide according to an example;

in the figure: 1-a raw material hopper; 2-a fan; 3-fluidized bed furnace; 4-a slag groove; 5-a waste gas treatment device; 6-a sublimation furnace; 7-condensation settling chamber; 8-finished product groove; 9-an exhaust chamber.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the terms "upper", "lower", "left" and "right" in the present application are consistent with the terms "upper", "lower", "left" and "right" in the drawings, but are not limited to specific structural orientations.

A preparation method of high-purity molybdenum oxide comprises the following steps of S110, S120, S130, S140 and S150, and the content of each step is described as follows:

in advance, the molybdenum concentrate is used as a raw material, as shown in fig. 1, the content of the specific steps is as follows:

a preparation method of high-purity molybdenum oxide takes molybdenum concentrate as a raw material, and specifically comprises the following steps:

s110, crushing and ball-milling the molybdenum concentrate to obtain molybdenum concentrate powder, wherein the granularity of the molybdenum concentrate powder is 50-300 meshes;

s120, carrying out preheating and drying treatment on the molybdenum concentrate powder to remove oil and water in the molybdenum concentrate powder, wherein the temperature range of preheating and drying is 100-350 ℃;

s130, placing the preheated and dried molybdenum concentrate powder in molybdenum concentrate preparation equipment for oxidation roasting reaction, wherein the temperature range of the oxidation roasting reaction is 450-680 ℃, and continuously introducing air into the equipment, wherein the air velocity of the introduced air is 0.8-15 m/S;

s140, sublimating the molybdenum calcine, wherein the product obtained after the oxidizing roasting reaction is the molybdenum calcine, and the sublimating temperature is 650-1050 ℃;

s150, condensing the molybdenum calcine, wherein the temperature range of condensation is 20-250 ℃.

The following preferred embodiments are provided for the above preparation method:

(1) the particle size of the molybdenum concentrate powder is less than 200 meshes, because the smaller the mesh number of the molybdenum concentrate powder is, the better the drying effect in the primary preheating drying process is, and the faster the corresponding drying speed is.

(2) The preheating drying temperature is more than 320 ℃, the preheating time is more than 5 seconds, and in the preheating drying state, the chemical property of the molybdenum concentrate powder is protected, and the preheating effect of the molybdenum concentrate powder is more perfect.

(3) The temperature range of the oxidizing roasting is 550-650 ℃, the retention time is more than 5 minutes, and the gas velocity is kept at 0.9-1.1 m/s; in the oxidation reaction process, the reaction temperature is in direct proportion to the reaction speed, namely the higher the temperature is, the faster the reaction speed is; the smaller the temperature range of high temperature, the more stable the reaction process and the less by-products of the reaction.

(4) The sublimation temperature range is 950-1050 ℃, because in the sublimation process, the higher the sublimation temperature is, the faster the sublimation speed is, and the chemical property integrity of the high-purity molybdenum oxide is ensured and the generation of other byproducts is reduced on the premise of guaranteeing high-efficiency sublimation in the temperature range.

(5) The preparation equipment should keep the continuous boiling state in the oxidizing roasting reaction, and the preparation equipment can reduce the sintering of molybdenum concentrate and the generation of molybdate by keeping the continuous boiling state, so that the oxidizing reaction is more thorough, and the reaction precision is improved.

Compared with the prior art, the method has the advantages of simple process, less loss of molybdenum in the process and high preparation precision of high-purity molybdenum oxide.

According to the preparation method of the high-purity molybdenum oxide, the invention also provides a preparation device of the high-purity molybdenum oxide, which is now explained as follows:

a preparation device of high-purity molybdenum oxide is shown in figure 2 and comprises: the device comprises a raw material hopper 1, a fan 2, a preheating and drying device, a fluidized bed furnace 3, a slag tank 4, waste gas treatment equipment 5, a sublimation furnace 6, a condensation settling chamber 7, a finished product tank 8 and a waste gas chamber 9, wherein an outlet of the raw material hopper 1 is connected with an inlet of the preheating and drying device, an outlet of the preheating device is connected with the fluidized bed furnace 3, a bottom outlet of the fluidized bed furnace 3 is connected with the slag tank 4, a middle reaction product outlet of the fluidized bed furnace 3 is connected with the sublimation furnace 6, an outlet of the sublimation furnace 6 is connected with the condensation settling chamber 7, a product outlet of the condensation settling chamber 7 is connected with the finished product tank 8, the bottom of the sublimation furnace 6 is connected with the slag tank 4, the top waste gas treatment equipment 5 of the fluidized bed furnace 3 is connected, and the middle part of the condensation settling chamber 7; the fluidized bed furnace 3 also comprises a heating pipeline and a waste heat recovery device, the waste heat recovery device is simultaneously connected with the preheating drying device and the sublimation furnace 6, and the waste heat recovery device is used for recovering waste heat in the heating pipeline; the fan 2 is connected with the fluidized bed furnace 3, and the fan 2 is used for introducing air with a certain wind speed into the fluidized bed furnace 3; a transpiration device and a stirring device are arranged in the sublimation furnace 6.

In the preparation equipment of the molybdenum oxide, the collection equipment of waste gas and waste residue is added, the collected waste gas is introduced into the waste gas chamber 9, and the waste gas is further treated and decomposed by the waste gas chamber 9, so that the discharged waste gas reaches the emission standard required by the environment; the slag in the slag groove 4 comprises a mixture of silicon dioxide and other metal oxides which are byproducts of the reaction, and the byproducts are collected and transferred to a smelting unit for further comprehensive utilization.

The preparation equipment for the high-purity molybdenum oxide has the following preferred scheme:

(1) the sublimation furnace 6 is cooled in an air refrigeration mode; the flow velocity of air in the sublimation process is controlled through the fan 2, so that the control is convenient, the operation is convenient, and the production cost is low.

(2) The section of the transpiration device in the fluidized bed furnace 3 comprises any one of an isosceles triangle, a trapezoid and an arc; isosceles triangle, trapezoidal and convex transpiration device has increased the transpiration area in the sublimation stove 6 for molybdenum trioxide sublimation process to reduce the production of molybdate.

Sublimation furnace 6 and condensation settling chamber 7 utilize fan 2 to supply air, in the sublimation process, fan 2 supplies air to sublimation furnace 6, make the surface air velocity of transpiration device of sublimation furnace 6 accelerate, thus has promoted the sublimation speed of high-purity molybdenum oxide, in the condensation process, utilize the condenser pipe to condense sublimed high temperature molybdenum oxide, wherein the condensation mode of condenser pipe is through letting in air constantly and realizing the refrigeration, fan 2 blows wind from the air inlet of cooling condenser pipe to the air outlet of condenser pipe, cool off the high temperature molybdenum oxide in the condenser pipe through wind; in the sublimation process, the stirring device indirectly increases the sublimation speed of the sublimation furnace 6 through stirring the molybdenum oxide on the surface of the transpiration device. The faster the sublimation, the less molybdate is produced.

In the preparation equipment of the high-purity molybdenum oxide, the collected waste gas is introduced into the waste gas chamber 9, and the waste gas is further treated and decomposed by the waste gas chamber 9, so that the discharged waste gas reaches the emission standard required by the environment; the slag in the slag groove 4 comprises a mixture of silicon dioxide and other metal oxides which are byproducts of the reaction, and the byproducts are collected and transferred to a smelting unit for further comprehensive utilization.

Compared with the prior art, the preparation equipment for high-purity molybdenum oxide provided by the invention realizes the preparation of high-purity molybdenum oxide with the purity of 99.9%, comprehensively simplifies the preparation process of molybdenum oxide, reduces the loss of molybdenum in the preparation process, reduces dangerous chemical risk sources and protects the safety of ecological environment.

The preparation method of the present invention is further described below with reference to specific test preparations and data:

a molybdenum concentrate containing 42.40% of Mo42, 5.28% of Ca5, 2.10% of Pb2, 2.13% of Fe2, 33.0% of S, 6.70% of Si and 8.39% of other molybdenum concentrates is ground into molybdenum concentrate powder, the molybdenum concentrate powder after being screened is screened by a 200-mesh screen, and the screened molybdenum concentrate powder is reserved for use. Preheating a transpiration furnace to 1000 ℃, preheating a fluidized bed furnace 3 to 600 ℃, keeping the gas velocity of the fluidized bed furnace 3 at 1.1m/s, opening the upper-layer cooling pipe gas flow, and keeping the temperature in the fluidized bed furnace 3 at 600 ℃; uniformly adding the screened molybdenum concentrate powder at the speed of 0.6t/h, opening a condensation pipe to flow water, stopping adding the material after one hour, stopping heating in a fluidized bed furnace 3 after 20 minutes, stopping heating in a transpiration furnace after 1 hour, closing the condensation pipe to supply water after 1.5 hours, and condensing the volatilized molybdenum trioxide. Through testing and calculation, the volatilization rate of Mo in the sample reaches 99.5%, the recovery rate of molybdenum trioxide reaches 99.3%, the purity of molybdenum trioxide reaches more than 99.9%, and the loss of molybdenum in the whole process is lower than 1%, which is far superior to the prior art.

According to the invention, the raw material molybdenum concentrate is preheated and dried in the preheating and drying device, so that the moisture and the oil in the molybdenum concentrate are removed, the preheated and dried molybdenum concentrate is put into the fluidized bed furnace 3 for oxidation roasting reaction, so that desulfurization is realized and relatively pure molybdenum trioxide is generated, and then the relatively pure molybdenum trioxide after oxidation desulfurization is subjected to sublimation and condensation post-treatment, so that the high-purity molybdenum trioxide is obtained. The preparation method and the preparation equipment realize high-precision preparation of high-purity molybdenum oxide, and have the characteristics of short process flow, simple preparation method, short process flow and high production efficiency. The preparation process of the molybdenum oxide is simplified, the preparation precision of the molybdenum oxide is improved, the loss of molybdenum in the preparation process is reduced, the risk source of dangerous chemicals is reduced, and the safety of the ecological environment is protected.

The present embodiment is only for explaining the invention, and it is not limited to the invention, and those skilled in the art can make modifications of the embodiment as necessary and inventive contribution to the present embodiment after reading the present specification, but all within the protection scope of the invention are protected by patent laws.