A pilot plant for preparing high-purity molybdenum oxide by microwave one-step method

Abstract

The invention discloses a pilot plant for preparing high-purity molybdenum oxide by microwave one-step method, including a reaction device, a dust removal device, a condensation device, and an exhaust gas treatment device. The main body of the reaction device is a reaction chamber, an air inlet pipe and a slag bucket are arranged at the lower end of the reaction chamber, a microwave generator is installed on the side wall of the reaction chamber, a feed pipe is connected to the top of the reaction chamber, a hollow stirring shaft is installed in the vertical section of the feed pipe, an air outlet pipe is connected to the left side of the feed pipe, the air outlet pipe is connected to the dust removal device, a dust collecting bucket is arranged at the lower end of the dust removal device, and the upper end is connected to the condensation device through a pipeline, a finished product barrel is arranged at the lower end of the condensation device, and the upper end is connected to the exhaust gas treatment device. The invention heats the raw material and reacts with the air by microwave, impurities enter the slag bucket, the air reacts with molybdenite, the sublimated molybdenum oxide gas is sucked into the dust removal device for dust removal, the gas enters the condensation device for crystallization, the finished product falls into the finished product barrel, and then the exhaust gas is treated; the production efficiency is high, the utilization rate is high, it is convenient and fast, and the pollution is small.

Description

Technical Field

[0001] The invention belongs to the technical field of unconventional metallurgical equipment, and in particular relates to a pilot plant for preparing high-purity molybdenum oxide by a one-step microwave method. Background Art

[0002] Molybdenum is a rare metal with high strength and high conductivity. Molybdenum and its compounds are widely used in many fields such as metallurgy, chemical industry, military industry and aerospace. Common molybdenum ores include molybdenite (MoS2), calcium molybdate ore (CaMoO4), lead molybdenite (PbMoO4) and blue molybdenite (Mo3O8·nH2O). Among them, molybdenite has the greatest industrial value and is mostly used as raw material for the preparation of molybdenum and molybdenum oxide (MoO3).

[0003] Microwaves refer to electromagnetic waves in free space with a frequency of 300MHz-300GHz and a wavelength of 1mm to 1m. Microwave energy is applied to metallurgical units, and its characteristics of selective heating, internal heating and non-contact heating are used to enhance the reaction process. Unlike conventional metallurgical heating methods, when microwaves are used to heat materials, the heat source is generated inside the object, and the heat is emitted from the inside of the object to the outside. The entire heating process is uniform and fast, and the heating time is greatly reduced. The inertia of microwave heating is very small, and the entire process can be well controlled, which is convenient for automatic control of continuous production. In addition, there is no hysteresis in microwave heating, and the microwave energy will disappear as the microwave source is turned off. No combustion gas will appear during the entire heating process, so microwave heating is clean, hygienic and pollution-free.

[0004] The microwave-assisted one-step preparation of molybdenum oxide from molybdenite is simple, and the purity of the MoO3 in the obtained product is very high. The main component of molybdenite is MoS2, which has good microwave absorption ability and can be raised to a very high temperature in a short time. When the temperature reaches 500°C, MoS2 will be oxidized. As the temperature rises, MoO3 will be generated under the condition of air. When the temperature reaches 600°C, volatile MoO2, SO2, SO3 gas and molybdate are generated.

[0005] Therefore, based on the above principle, this paper proposes a pilot plant for preparing high-purity molybdenum oxide by a one-step microwave method. Summary of the invention

[0006] In order to solve the above technical problems, the present invention designs a pilot plant for preparing high-purity molybdenum oxide by a one-step microwave method. The device conveys raw materials through a feed port and a rotary feeder, heats them through microwaves, and reacts with air; impurities enter a slag bucket to free up space, react continuously, and improve reaction efficiency; air introduced through an air intake pipe is heated between an outer hopper and an inner hopper, reacts with molybdenite, and sublimated molybdenum oxide gas is sucked into a dust removal device; in the dust removal device, dust gradually falls into a dust collecting bucket, and the gas enters a condensing device, becomes solid, and falls into a finished molybdenum oxide barrel, and the remaining harmful gases are sucked into an exhaust gas absorption barrel by a fan for treatment to generate reusable substances, thereby preventing air pollution and improving utilization rate. The entire device can perform continuous reactions, providing convenience while greatly improving production efficiency.

[0007] In order to achieve the above technical effect, the present invention is realized through the following technical scheme: a pilot plant for preparing high-purity molybdenum oxide by a microwave one-step method, comprising a reaction device, a dust removal device, a condensation device and an exhaust gas treatment device, characterized in that: the main body of the reaction device is a reaction cavity, an air inlet pipe and a slag bucket are arranged at the lower end of the reaction cavity, a microwave generator is installed on the side wall of the reaction cavity, a feed pipe is connected to the top of the reaction cavity, a hollow stirring shaft is installed in the vertical section of the feed pipe, an air outlet pipe is connected to the left side of the feed pipe, the air outlet pipe is connected to the dust removal device, a dust collecting bucket is arranged at the lower end of the dust removal device, and the upper end is connected to the condensation device through a pipeline, a finished product barrel is arranged at the lower end of the condensation device, and the upper end is connected to the exhaust gas treatment device through a pipeline.

[0008] Furthermore, the feed pipe is L-shaped, a feed spiral is installed in the horizontal section of the feed pipe, and a feed port is installed at the end of the horizontal section of the feed pipe; a thermocouple is installed above the vertical section of the feed pipe.

[0009] Furthermore, a heat-insulating material is arranged inside the reaction chamber, and a ceramic tube is arranged inside the reaction chamber, and the ceramic tube is installed between the feed pipe and the heat-insulating material; a spiral convex groove is arranged at the lower part of the hollow stirring shaft; an external hopper is connected to the lower part of the reaction chamber, an internal hopper is arranged inside the external hopper, the internal hopper is connected to the ceramic tube above, the air inlet pipe is connected in the middle of the internal hopper, and a rotary feeder is detachably connected to the lower part of the external hopper, and a slag bucket is connected to the lower end of the rotary feeder.

[0010] Furthermore, the microwave generator includes an excitation magnetron generator, an aluminum waveguide and a cooling aluminum waveguide seat.

[0011] Furthermore, the main body of the dust removal device is a cyclone dust collector, and the dust discharge port of the cyclone dust collector is detachably connected to a rotary feeder, and the lower end of the rotary feeder is connected to a dust collecting bucket.

[0012] Furthermore, the main body of the condensing device is a condenser, and a plurality of cooling air pipes are arranged inside the condenser. A rotary feeder is installed between the condenser and the finished product barrel.

[0013] Furthermore, a fan is installed between the tail gas treatment device and the condensation device, and alkaline substances are placed in the tail gas treatment device, including one or more of sodium hydroxide solution and lime milk.

[0014] Another object of the present invention is to provide a method for using a pilot plant for preparing high-purity molybdenum oxide by a one-step microwave method, characterized in that:

[0015] (1) When in use, first start the microwave generator, then feed molybdenite from the feed port, and the feed screw feeds the molybdenite into the ceramic tube in the reaction chamber, and at the same time, open the hollow stirring shaft to allow the material to fully react with the air in the chamber, and slow down the falling speed of the molybdenite, so that the MoS2 in the molybdenite is completely reacted;

[0016] (2) At this time, air is introduced from the air inlet pipe and enters the interlayer between the inner hopper and the outer hopper. Since molybdenite has good wave absorption performance, it is first heated and sublimated into molybdenum oxide gas. After the reaction, the remaining waste slag is discharged into the slag bucket through the outer hopper and the rotary feeder, and the generated gas enters the cyclone dust collector through the air outlet pipe;

[0017] (3) The material entering the cyclone dust collector is composed of MoO3 gas and some dust. In the cyclone dust collector, the dust falls due to its own gravity and is discharged into the dust collecting bucket by the rotary feeder, while the gas is discharged into the condenser through the pipeline;

[0018] (4) The molybdenum oxide obtained after gas condensation is discharged into a molybdenum oxide collection barrel by a rotary feeder, and the SO2 and SO3 gases generated in the reaction are sucked into the exhaust gas absorption barrel by a fan for recovery and reuse.

[0019] The beneficial effects of the present invention are:

[0020] Molybdenite is continuously transported into the reaction chamber by a rotary feeder through the feed port, and enters the ceramic tube for heating by microwaves. At the same time, the hollow stirring shaft starts to rotate, so that the molybdenite can fully contact with the air in the ceramic tube to react while being heated; impurities that cannot be heated by absorbing microwaves will move downward with the rotation of the stirring shaft and enter the slag collecting bucket, making room for the molybdenite that continuously enters the cavity, reacting continuously and improving the reaction efficiency; the molybdenite absorbs microwaves and sublimates into molybdenum oxide gas, which can make the inside of the ceramic tube higher, and pass through the oxygen inlet The oxygen introduced can be heated between the outer hopper and the inner hopper, and then gradually enter the ceramic tube to react with molybdenite. The sublimated molybdenum oxide gas is sucked into the air pipe above the reaction chamber and enters the dust removal device; in the dust removal device, the dust brought in gradually falls down and enters the slag collection bucket. The gas after dust removal enters the condensation device from the air pipe. After cooling, the molybdenum oxide becomes solid and falls into the molybdenum oxide collection bucket. The remaining harmful gases are sucked into the tail gas absorption bucket by the Roots blower for treatment, generating reusable substances, preventing air pollution while improving utilization. The entire device can carry out continuous reactions, providing convenience while greatly improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0022] Figure 1 The overall structure diagram of the present invention is

[0023] Figure 2 The internal structure diagram of the reaction device in the present invention

[0024] Figure 3 The schematic diagram of the structure of the microwave generator in the present invention is

[0025] Figure 4 The schematic diagram of the structure of the cyclone dust collector in the present invention is

[0026] Figure 5 The schematic diagram of the structure of the condensing device in the present invention is

[0027] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0028] 1 reaction chamber; 2 reducer; 3 thermocouple; 4 hollow stirring shaft; 5 feed port; 6 feed screw; 7 feed pipe; 8 microwave generator; 9 insulation material; 10 air inlet pipe; 11 external hopper; 12 rotary feeder; 13 cyclone dust collector; 14 air outlet pipe; 15 pipeline; 16 condenser; 17 fan; 18 exhaust gas treatment device; 19 ceramic tube; 20 spiral convex groove; 21 internal hopper; 22 excitation magnetron generator; 23 aluminum wave channel; 24 cooling aluminum wave channel seat; 25 cooling air pipe; 28 soil slag bucket; 29 dust collection bucket; 30 finished product bucket. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Example 1

[0031] See also Figures 1 to 5 As shown, a pilot plant for preparing high-purity molybdenum oxide by a one-step microwave method comprises a reaction device, a dust removal device, a condensation device and an exhaust gas treatment device 18, characterized in that: the main body of the reaction device is a reaction chamber 1, an air inlet pipe 10 and a slag bucket are arranged at the lower end of the reaction chamber 1, a microwave generator 8 is installed on the side wall of the reaction chamber 1, a feed pipe 7 is connected to the top of the reaction chamber 1, a hollow stirring shaft 4 is installed in the vertical section of the feed pipe 7, an air outlet pipe 14 is connected to the left side of the feed pipe 7, the air outlet pipe 14 is connected to the dust removal device, a dust collecting bucket 29 is arranged at the lower end of the dust removal device, and the upper end is connected to the condensation device through a pipeline 15, a finished product barrel 30 is arranged at the lower end of the condensation device, and the upper end is connected to the exhaust gas treatment device 18 through the pipeline 15.

[0032] The feed pipe 7 is L-shaped, a feed screw 6 is installed in the horizontal section of the feed pipe 7, and a feed port 5 is installed at the end of the horizontal section of the feed pipe 7; a thermocouple 3 is installed above the vertical section of the feed pipe 7.

[0033] The reaction chamber 1 is provided with a heat-insulating material 9, and a ceramic tube 19 is arranged inside the reaction chamber 1, and the ceramic tube 19 is installed between the feed pipe 7 and the heat-insulating material 9; the lower part of the hollow stirring shaft 4 is provided with a spiral convex groove 20; the lower part of the reaction chamber 1 is connected to an outer hopper 11, and an inner hopper 21 is arranged inside the outer hopper 11, and the inner hopper 21 is connected to the upper ceramic tube 19, and the air intake pipe 10 is connected to the middle part of the inner hopper 21, and the lower part of the outer hopper 11 is detachably connected to a rotary feeder 12, and the lower end of the rotary feeder 12 is connected to a slag bucket.

[0034] The microwave generator 8 includes an excitation magnetron generator 22 , an aluminum waveguide 23 and a cooling aluminum waveguide seat 24 .

[0035] The main body of the dust removal device is a cyclone dust collector 13 , and the dust outlet of the cyclone dust collector 13 is detachably connected to the rotary feeder 12 , and the lower end of the rotary feeder 12 is connected to the dust collecting bucket 29 .

[0036] The main body of the condensing device is a condenser 16 , and a plurality of cooling air pipes 25 are arranged inside the condenser 16 . A rotary feeder 12 is installed between the condenser 16 and the finished product barrel 30 .

[0037] A fan 17 is installed between the tail gas treatment device 18 and the condensing device. Alkaline substances are placed in the tail gas treatment device 18, including one or more of sodium hydroxide solution and lime milk.

[0038] Example 2

[0039] Instructions for use: When in use, first start the microwave generator 8, then feed the molybdenite from the feed port 5, and the feed screw 6 feeds the molybdenite into the ceramic tube 19 in the reaction chamber 1, and at the same time open the hollow stirring shaft 4 to allow the material to fully react with the air in the chamber, and to slow down the falling speed of the molybdenite, so that the MoS2 in the molybdenite is completely reacted; at this time, air is introduced from the air inlet pipe 10, and the air enters the interlayer between the inner hopper 21 and the outer hopper 11. Due to the good wave absorption performance of the molybdenite, it is first heated and sublimated into molybdenum oxide gas, and the remaining waste slag after the reaction is removed by the outer hopper. The bucket 11 and the rotary feeder 12 discharge into the slag bucket, and the generated gas enters the cyclone dust collector 13 through the outlet pipe 14; the material entering the cyclone dust collector 13 is composed of MoO3 gas and some dust. In the cyclone dust collector 13, the dust falls due to its own gravity and is discharged into the dust collecting bucket 29 by the rotary feeder 12, and the gas is discharged into the condenser 16 through the pipeline 15; the molybdenum oxide obtained after the gas is condensed is discharged into the molybdenum oxide collection bucket by the rotary feeder 12, and the SO2 and SO3 gases generated in the reaction are sucked into the exhaust gas absorption bucket by the fan 17 for recovery and reuse.

[0040] Example 3

[0041] Molybdenite is continuously transported into the reaction chamber 1 by the rotary feeder 12 through the feed port 5, and enters the ceramic tube 19 for heating by microwaves. At the same time, the hollow stirring shaft 4 starts to rotate, so that the molybdenite can fully contact with the air in the ceramic tube 19 to react while being heated; impurities that cannot be heated by absorbing microwaves will move downward along with the rotation of the stirring shaft and enter the slag collecting bucket, making room for the molybdenite that continuously enters the cavity, reacting continuously and improving the reaction efficiency; the molybdenite absorbs microwaves and sublimates into molybdenum oxide gas, which can make the inside of the ceramic tube 19 higher, and the oxygen inlet port The oxygen introduced can be heated between the outer hopper 11 and the inner hopper 21, and then gradually enter the ceramic tube 19 to react with molybdenite. The sublimated molybdenum oxide gas is sucked into the air pipe above the reaction chamber 1 and enters the dust removal device; in the dust removal device, the dust brought in gradually falls down and enters the slag collection bucket. The gas after the dust is removed enters the condensation device from the air pipe. After cooling, the molybdenum oxide becomes solid and falls into the molybdenum oxide collection bucket. The remaining harmful gas is sucked into the tail gas absorption bucket by the Roots blower 17 for treatment, generating reusable substances, preventing air pollution while improving utilization. The entire device can carry out continuous reactions, providing convenience while greatly improving production efficiency.

[0042] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0043] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A pilot plant for preparing high-purity molybdenum oxide by a microwave one-step method, comprising a reaction device, a dust removal device, a condensation device and an exhaust gas treatment device, characterized in that: The main body of the reaction device is a reaction cavity, an air inlet pipe and a slag bucket are arranged at the lower end of the reaction cavity, a microwave generator is installed on the side wall of the reaction cavity, a feed pipe is connected to the top of the reaction cavity, a hollow stirring shaft is installed in the vertical section of the feed pipe, an air outlet pipe is connected to the left side of the feed pipe, the air outlet pipe is connected to the dust removal device, a dust collecting bucket is arranged at the lower end of the dust removal device, and the upper end is connected to the condensation device through a pipeline, a finished product bucket is arranged at the lower end of the condensation device, and the upper end is connected to the tail gas treatment device through a pipeline; The feed pipe is L-shaped, a feed spiral is installed in the horizontal section of the feed pipe, and a feed port is installed at the end of the horizontal section of the feed pipe; a thermocouple is installed above the vertical section of the feed pipe; The reaction chamber is provided with a heat-insulating material, and a ceramic tube is provided inside the reaction chamber, and the ceramic tube is installed between the feed tube and the heat-insulating material; the lower part of the hollow stirring shaft is provided with a spiral convex groove; the lower part of the reaction chamber is connected with an outer hopper, and an inner hopper is provided inside the outer hopper, and the inner hopper is connected with the upper ceramic tube, and the air inlet pipe is connected in the middle of the inner hopper, and the lower part of the outer hopper is detachably connected with a rotary feeder, and the lower end of the rotary feeder is connected with a slag bucket; The microwave generator includes an excitation magnetron generator, an aluminum wave channel and a cooling aluminum wave channel seat; the main body of the dust removal device is a cyclone dust collector, the dust drop port of the cyclone dust collector is detachably connected to a rotary feeder, and the lower end of the rotary feeder is connected to a dust collecting bucket; the main body of the condensing device is a condenser, and a plurality of cooling air pipes are arranged inside the condenser, and a rotary feeder is installed between the condenser and the finished product barrel; a fan is installed between the exhaust gas treatment device and the condensing device, and alkaline substances are placed in the exhaust gas treatment device, including one or more of sodium hydroxide solution and lime milk.

2. The method for using the pilot plant for preparing high-purity molybdenum oxide by a microwave one-step method according to claim 1, characterized in that: (1) When in use, first start the microwave generator, then feed molybdenite from the feed port, and the feed screw feeds the molybdenite into the ceramic tube in the reaction chamber, and at the same time, open the hollow stirring shaft to allow the material to fully react with the air in the chamber, and slow down the falling speed of the molybdenite, so that the MoS2 in the molybdenite is completely reacted; (2) At this time, air is introduced from the air inlet pipe and enters the interlayer between the inner hopper and the outer hopper. Since molybdenite has good wave absorption performance, it is first heated and sublimated into molybdenum oxide gas. After the reaction, the remaining waste slag is discharged into the slag bucket through the outer hopper and the rotary feeder, and the generated gas enters the cyclone dust collector through the air outlet pipe; (3) The material entering the cyclone dust collector is composed of MoO3 gas and some dust. In the cyclone dust collector, the dust falls due to its own gravity and is discharged into the dust collecting bucket by the rotary feeder, while the gas is discharged into the condenser through the pipeline; (4) The molybdenum oxide obtained after gas condensation is discharged into a molybdenum oxide collection barrel by a rotary feeder, and the SO2 and SO3 gases generated in the reaction are sucked into the exhaust gas absorption barrel by a fan for recovery and reuse.

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