CN108622936B

CN108622936B - System and method for preparing high-purity vanadium pentoxide powder by efficient clean chlorination method

Info

Publication number: CN108622936B
Application number: CN201710161557.7A
Authority: CN
Inventors: 范川林; 朱庆山; 杨海涛
Original assignee: Institute of Process Engineering of CAS
Current assignee: Institute of Process Engineering of CAS
Priority date: 2017-03-17
Filing date: 2017-03-17
Publication date: 2020-02-18
Anticipated expiration: 2037-03-17
Also published as: CN108622936A

Abstract

The present invention belongs to the field of metallurgy and chemical industry. The invention discloses a system and a method for preparing high-purity vanadium pentoxide powder by a high-efficiency clean chlorination method, wherein industrial-grade vanadium oxide is converted into vanadium oxychloride by adopting fluidized carbon-matching chlorination, and crude vanadium oxychloride is obtained by two-stage dust removal and four-stage leaching; and purifying, catalytically oxidizing and calcining the crude vanadium oxychloride to obtain high-purity vanadium pentoxide powder. The method prevents the over-high furnace temperature by spraying the vanadium oxychloride slurry to the boiling chlorination furnace; the regeneration of chlorine is realized by blowing clean oxygen-enriched air into the catalytic oxidation fluidized bed; the hydrochloric acid is returned to the catalytic oxidation fluidized bed, so that the recycling of the hydrogen chloride is realized. The method has the advantages of strong adaptability of raw materials, self-circulation of chlorine, no discharge of vanadium-containing hydrochloric acid, low production energy consumption and operation cost, stable product quality and the like, is suitable for large-scale industrial production of high-purity vanadium pentoxide powder with the purity of more than 4N, and has good economic benefit and social benefit.

Description

System and method for preparing high-purity vanadium pentoxide powder by efficient clean chlorination method

Technical Field

The invention belongs to the field of metallurgy and chemical industry, and particularly relates to a system and a method for preparing high-purity vanadium pentoxide powder by an efficient clean chlorination method.

Background

With the continuous development of new energy technology, the demand of the battery industry for high-purity vanadium pentoxide (with the purity of more than 3N 5) is increasingly strong, and the demand comprises an all-vanadium redox flow battery (VRB) with good large-scale energy storage performance, a vanadate lithium ion battery for electric automobiles and the like.

At present, the process technology for preparing high-purity vanadium pentoxide is roughly divided into two types: wet purification process and chlorination purification process. The main process route of wet purification is as follows: purifying a vanadium solution, precipitating ammonium salt, calcining and vanadic oxide. In the wet process, a large amount of wastewater is generated in the operation steps of extraction/back extraction, precipitation, washing and the like, wherein the wastewater mainly contains a small amount of vanadium ions, ammonium ions and a large amount of sodium salts, the treatment difficulty is high, the pollution problem is obvious, and the large-scale industrial application of the wastewater is seriously made.

The main process route for purifying vanadium pentoxide by a chlorination method is as follows: raw materials containing vanadium-chloridizing, rectifying and purifying-subsequently processing. The preparation technology of high-purity vanadium pentoxide by a chlorination method is developed for a long time and gradually perfected. In the last 60 s, researchers at the Ohiowa State university of America used ammonium polyvanadate-carbochlorination-vanadium oxychloride distillation-ammonium salt precipitation-calcination to prepare high-purity vanadium pentoxide (Journal of the Less-common metals,1960,2: 29-35). In the document, high-purity vanadium oxychloride is directly added into ammonia water, so that the treatment difficulty is high, the recovery rate is low, and a large amount of waste water containing ammonium chloride is generated. In 2011, chinese patent application CN103130279A discloses a process route for preparing high-purity vanadium pentoxide by a chlorination method. The patent adopts a process route of vanadium-containing substance-carbon preparation chlorination-dust removal-condensation-rectification-ultrapure water hydrolysis/ammonium salt precipitation-calcination to prepare high-purity vanadium pentoxide. This patent is similar to the aforementioned research at the Iowa State university of America, and only shows the principle flow of chlorination, and is practically difficult to implement; in addition, vanadium oxychloride is introduced into the ultrapure water solution/ultrapure ammonia water, so that the recovery rate is very low, and the problem of serious water pollution is caused.

In recent years, the research institute of process engineering of the Chinese academy of sciences has conducted a great deal of research on the preparation technology of the chlorination-process high-purity vanadium oxide, so that the preparation technology of the chlorination-process high-purity vanadium oxide is gradually improved, and a good large-scale industrial application prospect is presented. However, the problems of system optimization and clean and efficient conversion of vanadium oxychloride still exist, and a solution is urgently needed. The chinese patent application CN105984896A proposes a system and a method for preparing high-purity vanadium pentoxide by using industrial-grade vanadium pentoxide as a raw material by a chlorination method, which prepares high-purity vanadium pentoxide by carbon preparation chlorination, dust removal condensation, rectification purification, gas phase ammonification, and ammonium vanadate calcination. The patent has the following disadvantages: (1) the carbon-matching chlorination is a violent exothermic process and needs to transfer heat to the outside of the chlorination furnace; in the patent, air is blown into the chlorination furnace, so that the temperature of the furnace is increased, and the fluidization state is influenced; (2) the flue gas dust removal-condensation part is very simple, a large amount of unreacted dust is mixed in the chlorinated flue gas, the single cyclone separator cannot achieve an effective dust removal effect, and the dust moves backwards to block a subsequent pipeline, so that the hidden trouble of production stop is brought; meanwhile, the recovery rate can be greatly reduced and the production cost can be increased due to insufficient condensation of vanadium oxychloride; (3) the rectification purification can only separate metal chlorides which have large difference with the saturated vapor pressure of the vanadium oxychloride, however, some titanium and silicon chlorides have similar saturated vapor pressure with the vanadium oxychloride, and the high-purity vanadium oxychloride is difficult to obtain by a single rectification method; (4) the gas phase ammonization-ammonium salt calcining process can generate a large amount of ammonium chloride and ammonia-rich tail gas, and the environmental protection cost is increased. The chinese patent application CN105984897A discloses a system and a method for preparing high-purity vanadium pentoxide powder by a similar chlorination method, which adopts the process technologies of carbon-matching chlorination, dust removal condensation, rectification purification, gas phase hydrolysis and fluidized calcination. The gas-phase hydrolysis process is adopted to replace a gas-phase ammonification process, so that the problems of ammonium chloride and ammonia-rich tail gas are solved. However, because a large amount of water is added and the oxygen concentration in the compressed air is low, a large amount of hydrochloric acid is generated by gas phase hydrolysis, and the treatment of the vanadium-containing hydrochloric acid can greatly improve the environmental protection cost; meanwhile, the patent technology also has the problems of overheating of the chlorination furnace, blockage of pipelines, low recovery rate of vanadium oxychloride and substandard purity of the vanadium oxychloride. Chinese patent application CN105984899A discloses a similar chlorination process for preparing high-purity vanadium pentoxide system and method, which adopts the process technologies of carbon-matching chlorination, dust-removing condensation, rectification purification and plasma oxidation. The plasma oxidation process is adopted to replace gas-phase ammonification and gas-phase hydrolysis processes, so that the problems of ammonia-rich tail gas and vanadium-containing hydrochloric acid are solved. However, the plasma oxidation technology is easy to have the problems that vanadium pentoxide is molten and scabs are generated due to overhigh temperature, and the oxidation recovery efficiency is low, so that the large-scale operation is difficult. The patent technology also has the problems of overheating of the chlorination furnace, blockage of pipelines, low recovery rate of vanadium oxychloride and substandard purity of the vanadium oxychloride. Chinese patent application CN105984900A discloses a system and a method for preparing high-purity vanadium pentoxide powder by chlorination method, which adopts the process technologies of carbon preparation chlorination, dust removal condensation, rectification purification, ammonium salt precipitation and fluidized calcination. The ammonium salt precipitation process can bring a large amount of ammonia nitrogen wastewater, and the environmental protection cost is increased. Meanwhile, the technology also has the problems of overheating of the chlorination furnace, pipeline blockage, low recovery rate of vanadium oxychloride and substandard purity of the vanadium oxychloride. Chinese patent application CN105986126A discloses a process for preparing vanadium pentoxide powder by chlorination method using vanadium slag as raw material. Adopts the processes of carbon matching chlorination, dust removal condensation, distillation purification and gas phase hydrolysis. The patent has the following disadvantages: (1) a large amount of impurities such as iron, manganese, chromium, titanium, aluminum and the like exist in the vanadium slag, and are converted into chlorides in a chlorination process, so that a large amount of chlorination tailings pollute the environment and cannot be economically and efficiently utilized; (2) the patent technology also has the problems of overheating of a chlorination furnace, blockage of pipelines, low recovery rate of vanadium oxychloride, substandard purity of vanadium oxychloride and incapability of processing a large amount of vanadium-containing hydrochloric acid. The chinese patent application CN105984898A discloses a system and a method for preparing high-purity vanadium tetraoxide by chlorination method, which adopts the process technologies of carbon preparation chlorination, dust removal condensation, rectification purification, gas phase hydrolysis and fluidized bed reduction. The patent technology also has the problems of overheating of a chlorination furnace, blockage of pipelines, low recovery rate of vanadium oxychloride, substandard purity of vanadium oxychloride and incapability of processing a large amount of vanadium-containing hydrochloric acid. The valence state of the vanadium tetraoxide is difficult to accurately control in the reduction process, and a cooling device is lacked after the reduction process, so that the problem of reoxidation of the high-temperature vanadium tetraoxide is caused. In addition, chinese patent application CN106257724A discloses a process for precipitation of ammonium salts of vanadium oxychloride, chinese patent application CN106257726A discloses a process for vapor phase ammonification of vanadium oxychloride, chinese patent application CN106257727A discloses a process for liquid phase hydrolysis, and chinese patent application CN106257728A discloses a process for vapor phase hydrolysis. The technologies disclosed in these patents are similar to the aforementioned patents, and mainly have the problems of ammonia nitrogen wastewater and vanadium-containing hydrochloric acid.

In addition, for industrial large-scale application, the existing industrial grade vanadium oxide chlorination technology still has the following four problems: (1) vanadium oxide chlorination belongs to a strong heat release process, heat generated by chlorination reaction can meet preheating of solid and gas reaction materials, and a large amount of heat is remained, so that the vanadium material is locally overheated, the fluidization state and the chlorination selectivity are influenced, and an effective method needs to be found to remove the heat out of a fluidized bed; (2) the dedusting and condensing section of the chlorinated flue gas is related to the continuity of production and the recovery rate of vanadium oxychloride, and a special device is required for reinforcement; (3) the rectification/distillation purification can only separate metal chlorides which have large difference with saturated vapor pressure of vanadium oxychloride, however, some titanium and silicon chlorides have similar saturated vapor pressure with vanadium oxychloride, and high-purity vanadium oxychloride is difficult to obtain by a rectification/distillation method alone, and other effective impurity removal methods are required to be matched; (4) the preparation of vanadium pentoxide by vanadium oxychloride still has no clean, efficient and environment-friendly preparation method. If the chlorine can not realize circulation and the vanadium-containing hydrochloric acid can not be effectively treated, the production cost and the environmental protection cost are greatly improved, and the large-scale industrialization is difficult to realize.

Therefore, the method realizes temperature regulation and control in the chlorination process, develops a novel process for efficiently purifying and converting vanadium oxychloride into vanadium pentoxide, realizes the circulation of chlorine, improves the direct yield of vanadium, avoids ammonia nitrogen emission pollution and reduces production energy consumption, and is the key for realizing large-scale industrialization of the technology for preparing high-purity vanadium pentoxide powder by a chlorination method.

Disclosure of Invention

Aiming at the problems, the invention provides a system and a method for preparing high-purity vanadium pentoxide powder by an efficient clean chlorination method, so as to ensure good selectivity of chlorination, realize chlorine gas circulation, avoid generation of a large amount of vanadium-containing hydrochloric acid, and reduce production energy consumption and operation cost of high-purity vanadium pentoxide. In order to achieve the purposes, the invention adopts the following technical scheme:

the invention provides a system for preparing high-purity vanadium pentoxide powder by an efficient clean chlorination method, which comprises a feeding section 1, a chlorination section 2, a dedusting and leaching section 3, a purification section 4, a catalytic oxidation section 5, a catalytic oxidation product feeding section 6, a preheating section 7 and a calcining section 8;

the feeding working section 1 comprises an industrial grade vanadium oxide material bin 1-1, an industrial grade vanadium oxide star-shaped feeder 1-2, a carbon source bin 1-3, a carbon source star-shaped feeder 1-4, a mixer 1-5 and a mixer star-shaped feeder 1-6;

the chlorination working section 2 comprises a boiling chlorination furnace feeder 2-1, a boiling chlorination furnace 2-2, a chlorination furnace cyclone separator 2-3, an underflow slurry nozzle 2-4, a supernatant slurry nozzle 2-5 and a chlorination residue discharger 2-6;

the dust removal and leaching working section 3 comprises a scraper dust removal tower 3-1, a gravity settling tower 3-2, a first-stage leaching tower 3-3, a slurrying pool 3-4, a second-stage leaching tower 3-5, a third-stage leaching tower 3-6, a fourth-stage leaching tower 3-7, a centrifugal filter 3-8, an activated carbon adsorption tower 3-9 and a vanadium oxychloride slurry tank 3-10;

the purification working section 4 comprises a hydrolysis impurity removal kettle 4-1, a distillation kettle 4-2, a rectifying tower 4-3, a vanadium oxychloride condenser 4-4, a vanadium oxychloride reflux tank 4-5 and a high-purity vanadium oxychloride storage tank 4-6;

the catalytic oxidation section 5 comprises a vanadium oxychloride vaporizer 5-1, a vanadium oxychloride nozzle 5-2, a clean oxygen-enriched air preheater 5-3, a catalytic oxidation fluidized bed 5-4 and a catalytic oxidation fluidized bed cyclone separator 5-5; 5-6 parts of a catalytic oxidation fluidized bed discharger and 5-7 parts of a hydrochloric acid condensation absorption tower;

the catalytic oxidation product feeding section 6 comprises a catalytic oxidation product bin 6-1 and a catalytic oxidation product star-shaped feeder 6-2;

the preheating section 7 comprises a preheating fluidized bed feeder 7-1, a preheating fluidized bed 7-2, a preheating fluidized bed discharger 7-3 and a preheating fluidized bed cyclone separator 7-4;

the calcination working section 8 comprises a calcination fluidized bed combustor 8-1, a calcination fluidized bed 8-2, a calcination fluidized bed cyclone separator 8-3, a calcination fluidized bed discharger 8-4 and a high-purity vanadium pentoxide bin 8-5;

a discharge hole at the bottom of the industrial-grade vanadium oxide material bin 1-1 is connected with a feed hole of the industrial-grade vanadium oxide star-shaped feeder 1-2; a discharge hole at the bottom of the carbon source bin 1-3 is connected with a feed hole of the carbon source star feeder 1-4; the discharge hole of the industrial grade vanadium oxide star feeder 1-2 and the discharge hole of the carbon source star feeder 1-4 are connected with the feed inlet of the mixer 1-5 through pipelines; a discharge hole at the bottom of the mixer 1-5 is connected with a feed hole of the mixer star-shaped feeder 1-6; the discharge hole of the mixer star-shaped feeder 1-6 is connected with the feed hole of the boiling chlorination furnace feeder 2-1 through a pipeline;

the discharge hole of the boiling chlorination furnace feeder 2-1 is connected with the feed inlet at the upper part of the boiling chlorination furnace 2-2 through a pipeline; an air inlet at the bottom of the boiling chlorination furnace feeder 2-1 is connected with an industrial nitrogen main pipe; the gas inlet at the lower part of the boiling chlorination furnace 2-2 is respectively connected with a chlorine gas source main pipe and an industrial nitrogen main pipe through pipelines; the underflow slurry nozzle 2-4 is positioned at the upper part of the boiling chlorination furnace 2-2; the feed inlets of the underflow slurry nozzles 2 to 4 are connected with the underflow outlets at the lower parts of the vanadium oxychloride slurry tanks 3 to 10 through pipelines; the upper clear slurry nozzle 2-5 is positioned at the lower part of the boiling chlorination furnace 2-2; the feed inlets of the supernatant slurry nozzles 2 to 5 are connected with the supernatant outlets in the middle of the vanadium oxychloride slurry tanks 3 to 10 through pipelines; the chlorination furnace cyclone separator 2-3 is arranged at the center of the top of the boiling chlorination furnace 2-2; a gas outlet at the top of the chlorination furnace cyclone separator 2-3 is connected with a hot flue gas inlet of the scraper dust removal tower 3-1 through a pipeline; a slag discharge port at the lower part of the boiling chlorination furnace 2-2 is connected with a feed inlet of the chlorination residue discharger 2-6 through a pipeline; the air inlet at the bottom of the chlorination residue discharger 2-6 is connected with an industrial nitrogen header pipe;

a vanadium oxychloride slurry inlet at the top of the scraper dust removal tower 3-1 is connected with a slurry outlet of the slurrying tank 3-4 through a pipeline; the vanadium oxychloride slurry inlet at the top of the scraper dust removal tower 3-1 is simultaneously connected with the bottom flow outlet of the distillation kettle 4-2 through a pipeline; the air outlet of the scraper dust removal tower 3-1 is connected with the air inlet of the gravity settling tower 3-2 through a pipeline; the gas outlet of the gravity settling tower 3-2 is connected with the gas inlet of the first-stage leaching tower 3-3 through a pipeline; the slurry outlet of the first-stage leaching tower 3-3 is connected with the slurry inlet of the slurrying pool 3-4 through a pipeline; the gas outlet of the first-stage leaching tower 3-3 is connected with the gas inlet of the second-stage leaching tower 3-5 through a pipeline; the liquid outlet of the second-stage leaching tower 3-5 is connected with the liquid inlet of the centrifugal filter 3-8 through a pipeline; the gas outlet of the second-stage leaching tower 3-5 is connected with the gas inlet of the third-stage leaching tower 3-6 through a pipeline; the liquid outlet of the third-stage leaching tower 3-6 is connected with the liquid inlet of the centrifugal filter 3-8 through a pipeline; the gas outlet of the third leaching tower 3-6 is connected with the gas inlet of the fourth leaching tower 3-7 through a pipeline; the liquid outlet of the four-stage leaching tower 3-7 is connected with the liquid inlet of the centrifugal filter 3-8 through a pipeline; the gas outlet of the four-stage leaching tower 3-7 is connected with the gas inlet of the activated carbon adsorption tower 3-9 through a pipeline; a supernatant outlet of the centrifugal filter 3-8 is connected with a liquid inlet of the hydrolysis impurity removal kettle 4-1 through a pipeline; the slurry outlet of the centrifugal filter 3-8 is connected with the slurry inlet of the vanadium oxychloride slurry tank 3-10 through a pipeline; the gas outlets of the activated carbon adsorption towers 3 to 9 are connected with the gas inlet of the tail gas treatment system through a pipeline;

the liquid outlet of the hydrolysis impurity removal kettle 4-1 is connected with the liquid inlet of the distillation kettle 4-2 through a pipeline; a gas outlet of the distillation kettle 4-2 is connected with a gas inlet at the bottom of the rectifying tower 4-3 through a pipeline; a reflux port of the distillation kettle 4-2 is connected with a liquid reflux outlet at the bottom of the rectifying tower 4-3 through a pipeline; a gas outlet at the top of the rectifying tower 4-3 is connected with a gas inlet of the vanadium oxytrichloride condenser 4-4 through a pipeline; the liquid outlet of the vanadium oxychloride condenser 4-4 is connected with the liquid inlet of the vanadium oxychloride reflux tank 4-5 through a pipeline; a reflux port of the vanadium oxytrichloride reflux tank 4-5 is connected with a liquid reflux port at the upper part of the rectifying tower 4-3 through a pipeline; a high-purity vanadium oxychloride liquid outlet (the purity of vanadium oxychloride in the high-purity vanadium oxychloride liquid is more than 4N) of the vanadium oxychloride reflux tank 4-5 is connected with a liquid inlet of the high-purity vanadium oxychloride storage tank 4-6 through a pipeline; a liquid outlet at the lower part of the high-purity vanadium trichloride storage tank 4-6 is connected with a liquid inlet of the vanadium trichloride vaporizer 5-1 through a pipeline;

the gas outlet of the vanadium trichloride vaporizer 5-1 is connected with the gas inlet of the vanadium trichloride nozzle 5-2 through a pipeline; the gas inlet of the vanadium oxychloride nozzle 5-2 is simultaneously connected with the clean oxygen-enriched air main pipe; the vanadium oxytrichloride nozzle 5-2 is arranged at the lower position in the middle of the catalytic oxidation fluidized bed 5-4; the air inlet of the clean oxygen-enriched air preheater 5-3 is connected with a clean oxygen-enriched air main pipe; the air outlet of the clean oxygen-enriched air preheater 5-3 is connected with the fluidizing gas inlet of the catalytic oxidation fluidized bed 5-4 through a pipeline; a clean water inlet of the catalytic oxidation fluidized bed 5-4 is respectively connected with a clean water main pipe and a clean oxygen-enriched air main pipe; the hydrochloric acid inlet of the catalytic oxidation fluidized bed 5-4 is connected with the hydrochloric acid liquid outlet of the hydrochloric acid condensation absorption tower 5-7 through a pipeline; the catalytic oxidation fluidized bed cyclone separator 5-5 is arranged at the center of the top of the catalytic fluidized bed 5-4; a gas outlet of the catalytic oxidation fluidized bed cyclone separator 5-5 is connected with a gas inlet of the hydrochloric acid condensation absorption tower 5-7 through a pipeline; the gas outlets of the hydrochloric acid condensation absorption towers 5 to 7 are connected with the gas inlet of the chlorine circulating system; the discharge hole at the bottom of the catalytic oxidation fluidized bed 5-4 is connected with the feed inlet of the catalytic oxidation fluidized bed discharger 5-6 through a pipeline; a loose air inlet at the bottom of the catalytic oxidation fluidized bed discharger 5-6 is connected with a clean oxygen-enriched air main pipe; the discharge hole of the catalytic oxidation fluidized bed discharger 5-6 is connected with the feed hole of the catalytic oxidation product bin 6-1 through a pipeline;

the discharge hole of the catalytic oxidation product bin 6-1 is connected with the feed hole of the catalytic oxidation product star feeder 6-2; the discharge hole of the catalytic oxidation product star-shaped feeder 6-2 is connected with the feed hole of the preheating fluidized bed feeder 7-1 through a pipeline;

the loosening air inlet at the bottom of the preheating fluidized bed feeder 7-1 is connected with the purified air main pipe; the discharge hole of the preheating fluidized bed feeder 7-1 is connected with the feed inlet of the preheating fluidized bed 7-2 through a pipeline; a high-temperature gas inlet at the bottom of the preheating fluidized bed 7-2 (the high-temperature gas refers to gas with the temperature of more than 300 ℃) is connected with a gas outlet of the calcining fluidized bed cyclone separator 8-3 through a pipeline; the preheating fluidized bed cyclone separator 7-4 is arranged in the center of the top of the preheating fluidized bed 7-2; the gas outlet of the preheating fluidized bed cyclone separator 7-4 is connected with the gas inlet of the tail gas treatment system through a pipeline; the discharge hole of the preheating fluidized bed 7-2 is connected with the feed hole of the preheating fluidized bed discharger 7-3 through a pipeline; the loose air inlet at the bottom of the preheating fluidized bed discharger 7-3 is connected with a purified air main pipe; the discharge hole of the discharger 7-3 of the preheating fluidized bed is connected with the feed hole of the calcining fluidized bed 8-2 through a pipeline;

the fuel inlet of the calcining fluidized bed combustor 8-1 is connected with a clean fuel main pipe; a combustion-supporting air inlet of the calcining fluidized bed combustor 8-1 is connected with a purified air main pipe; a high-temperature gas outlet of the calcining fluidized bed combustor 8-1 (the high-temperature gas refers to gas with the temperature of more than 300 ℃) is connected with a fluidizing gas inlet of the calcining fluidized bed 8-2 through a pipeline; the calcination fluidized bed cyclone separator 8-3 is arranged at the top center of the calcination fluidized bed 8-2, and the discharge hole of the calcination fluidized bed 8-2 is connected with the feed hole of the calcination fluidized bed discharger 8-4 through a pipeline; a loosening air inlet at the bottom of the calcining fluidized bed discharger 8-4 is connected with a purified air main pipe; the discharge hole of the calcining fluidized bed discharger 8-4 is connected with the feed hole of the high-purity vanadium pentoxide bin 8-5 through a pipeline; and a discharge port with a valve is arranged at the bottom of the high-purity vanadium pentoxide bin 8-5.

In a second aspect, the invention provides a method for preparing high-purity vanadium pentoxide powder by an efficient clean chlorination method based on the system, which comprises the following steps:

industrial vanadium oxide in the industrial vanadium oxidation material bin 1-1 and a carbon source in the carbon source bin 1-3 simultaneously enter the mixer 1-5 to be mixed through the industrial vanadium oxide star feeder 1-2 and the carbon source star feeder 1-4 respectively; the mixed materials sequentially pass through the mixer star-shaped feeder 1-6 and the boiling chlorination furnace feeder 2-1 to enter the boiling chlorination furnace 2-2; chlorine from a chlorine gas source main pipe and nitrogen from an industrial nitrogen main pipe enter through a gas inlet at the lower part of the boiling chlorination furnace 2-2 to form a mixed gas of the chlorine and the nitrogen, so that industrial-grade vanadium oxide and a carbon source are kept fluidized and are subjected to chemical reaction with the industrial-grade vanadium oxide and the carbon source, and the chlorine and the carbon source act together to cause the vanadium oxide and impurities to undergo chlorination reaction to form chlorination residues and chlorination flue gas containing vanadium oxychloride; vanadium oxychloride slurry from the vanadium oxychloride slurry tank 3-10 is respectively sprayed into the boiling chlorination furnace 2-2 through the underflow slurry nozzle 2-4 and the supernatant slurry nozzle 2-5, and the temperature in the furnace is adjusted; the chlorination residues are discharged through a residue discharge port at the lower part of the boiling chlorination furnace 2-2 and the chlorination residue discharger 2-6 in sequence; removing dust from the chlorination flue gas through the chlorination furnace cyclone separator 2-3, feeding the chlorination flue gas into the scraper dust removal tower 3-1, and returning the removed dust to the boiling chlorination furnace 2-2;

a slurry nozzle is arranged at the top of the scraper dust removal tower 3-1, and slurry from the slurrying pool 3-4 and bottom flow of the distillation kettle 4-2 enter the scraper dust removal tower 3-1 through the slurry nozzle to cool chlorination flue gas; the generated dust collection slag is discharged through a slag discharge port at the lower part of the scraper dust removal tower 3-1 and is sent for treatment; the chloridized flue gas after primary dedusting and cooling enters the gravity settling tower 3-2 for gravity settling, and the generated dust is discharged through a slag discharge port at the lower part of the gravity settling tower 3-2 and is sent for treatment; the flue gas after the gravity settling treatment is sent to the first-stage leaching tower 3-3 for first-stage leaching, and first-stage leaching slurry is slurried in the slurrying tank 3-4; sending the first-stage leaching tail gas to the second-stage leaching tower 3-5 for second-stage leaching, and sending the second-stage leaching slurry to the centrifugal filter 3-8 for treatment; sending the second-stage leaching tail gas to the third-stage leaching tower 3-6 for third-stage leaching, and sending the third-stage leaching slurry to the centrifugal filter 3-8 for treatment; sending the three-stage leaching tail gas to the four-stage leaching tower 3-7 for four-stage leaching, and sending the four-stage leaching slurry to the centrifugal filter 3-8 for treatment; after the four-stage leaching tail gas is treated by the activated carbon adsorption tower 3-9, the tail gas is sent to the tail gas treatment system for treatment; the slurry at the bottom of the centrifugal filter 3-8 is sent to the vanadium oxychloride slurry tank 3-10 for sedimentation treatment, and the supernatant at the top is sent to the hydrolysis impurity removal kettle 4-1 for pre-impurity removal treatment;

feeding the vanadium oxychloride slurry subjected to pre-impurity removal in the hydrolysis impurity removal kettle 4-1 into the distillation kettle 4-2 for distillation, and feeding the distilled gas into the rectifying tower 4-3 for rectification treatment; the evaporation concentrated solution generated by distillation is sprayed into the scraper dust removal tower 3-1 through a nozzle at the top of the scraper dust removal tower 3-1; the high boiling point component in the rectifying tower 4-3 (the high boiling point component refers to a component with a boiling point of over 127 ℃) enters the distillation kettle 4-2 through a reflux port; after vanadium oxychloride steam in the rectifying tower 4-3 is condensed to liquid by the vanadium oxychloride condenser 4-4, part of the vanadium oxychloride steam flows back to the rectifying tower 4-3 through the vanadium oxychloride reflux tank 4-5, and the rest of the vanadium oxychloride steam enters the high-purity vanadium oxychloride storage tank 4-6;

the high-purity vanadium oxychloride in the high-purity vanadium oxychloride storage tank 4-6 is gasified by the vanadium oxychloride vaporizer 5-1 (the high-purity vanadium oxychloride is vanadium oxychloride with the purity of more than 4N), and then enters the catalytic oxidation fluidized bed 5-4 together with clean oxygen-enriched air through the vanadium oxychloride nozzle 5-2; clean water from a clean water main and clean oxygen-enriched air from a clean oxygen-enriched air main enter the catalytic oxidation fluidized bed 5-4 together through a clean water inlet of the catalytic oxidation fluidized bed 5-4; hydrochloric acid from the hydrochloric acid condensation absorption tower 5-7 enters the catalytic oxidation fluidized bed 5-4 through a hydrochloric acid inlet of the catalytic oxidation fluidized bed 5-4; the clean oxygen-enriched air from the clean oxygen-enriched air main pipe is preheated by the clean oxygen-enriched air preheater 5-3 and then enters the catalytic oxidation fluidized bed 5-4 through a fluidizing gas inlet at the bottom of the catalytic oxidation fluidized bed 5-4; vanadium oxychloride in the catalytic oxidation fluidized bed 5-4 forms vanadium pentoxide powder and flue gas containing chlorine and hydrogen chloride under the catalytic oxidation action of clean water and clean oxygen-enriched air; vanadium pentoxide powder enters the catalytic oxidation product bin 6-1 through the catalytic oxidation fluidized bed discharger 5-6; flue gas containing chlorine and hydrogen chloride is dedusted by the catalytic oxidation fluidized bed cyclone separator 5-5 and then enters the hydrochloric acid condensation absorption tower 5-7 for condensation absorption, hydrochloric acid obtained by condensation absorption returns to the catalytic oxidation fluidized bed 5-4, and the rest chlorine is sent to a chlorine circulating system;

vanadium pentoxide powder in the catalytic oxidation product bin 6-1 enters the preheating fluidized bed 7-2 through the catalytic oxidation product star feeder 6-2 and the preheating fluidized bed feeder 7-1; calcining tail gas from the calcining fluidized bed cyclone separator 8-3 enters the preheating fluidized bed 7-2 through a fluidizing gas inlet at the bottom of the preheating fluidized bed 7-2, so that vanadium pentoxide powder is fluidized and heat exchange is realized, and the heat exchange tail gas is dedusted by the preheating fluidized bed cyclone separator 7-4 and then is sent to a tail gas treatment system; vanadium pentoxide powder preheated by the preheating fluidized bed 7-2 enters the calcining fluidized bed 8-2 through the discharger 7-3 of the preheating fluidized bed;

the purified air from the purified air main pipe and the clean fuel from the clean fuel main pipe are combusted in the combustion chamber 8-1, and the generated high-temperature gas (the high-temperature gas refers to gas with the temperature of more than 300 ℃) enters the calcining fluidized bed 8-2 through a fluidizing gas inlet at the bottom of the calcining fluidized bed 8-2 to maintain the fluidization of the vanadium pentoxide powder, and water and trace volatile substances are removed from the vanadium pentoxide powder to obtain high-purity vanadium pentoxide powder (the high-purity vanadium pentoxide powder is vanadium pentoxide powder with the purity of more than 4N) and calcining flue gas; the calcining flue gas is dedusted by the calcining fluidized bed cyclone separator 8-3 and then is sent to the preheating fluidized bed 7-2 for preheating powder; and discharging a high-purity vanadium pentoxide product through the calcining fluidized bed discharger 8-4 into the high-purity vanadium pentoxide bin 8-5.

In the invention, the clean oxygen-enriched air refers to air with the oxygen content of 30-95% by volume; the high-purity vanadium pentoxide powder is vanadium pentoxide powder with the purity of more than 4N (wherein 4N is 99.99%).

As a preferable technical scheme of the invention, the upper part of the boiling chlorination furnace 2-2 is provided with the underflow slurry nozzle 2-4, and the lower part of the boiling chlorination furnace 2-2 is provided with the supernatant slurry nozzle 2-5 for spraying the vanadium oxychloride slurry to regulate the temperature of the chlorination furnace.

As the preferable technical scheme of the invention, the scraper dust removal tower 3-1 is a rotary dust removal device provided with a scraper, so that the collected sediment can be effectively prevented from being bonded to the wall.

As the preferable technical scheme of the invention, the hydrochloric acid condensation absorption tower 5-7 is arranged in the catalytic oxidation section 5 and is used for recycling vanadium-containing hydrochloric acid.

As the preferable technical scheme of the invention, the industrial-grade vanadium oxide in the industrial-grade vanadium oxide material bin 1-1 is industrial-grade vanadium trioxide, vanadium tetraoxide, vanadium pentoxide and a mixture thereof; the carbon source in the carbon source bins 1-3 refers to any one or a combination of at least two of activated carbon, metallurgical coke, petroleum coke or coal powder; the addition amount of the carbon source in the chlorination reaction process is 5-30% of the mass of the industrial-grade vanadium oxide.

Wherein, the "industrial grade vanadium oxide" refers to vanadium oxide with the purity of main components more than 80 wt%, and the main components refer to vanadium oxide.

As a preferable technical scheme of the invention, in the boiling chlorination furnace 2-2, the operation temperature of chlorination reaction is 290-600 ℃; the operating gas velocity of the fluidization section is 0.05-3.00 m/s, and the mole fraction of chlorine in the mixed gas of chlorine and nitrogen entering the 2-2 wind chambers of the boiling chlorination furnace is 20-100%.

As a preferable technical scheme of the invention, the pre-impurity removal in the hydrolysis impurity removal kettle 4-1 is to remove impurities titanium and silicon in the vanadium oxychloride slurry by using a selective hydrolysis method, the impurity removal agent is water or an aqueous solution, and the dosage of the impurity removal agent is 0.00001-0.1% of the mass of the vanadium oxychloride slurry. Here, the aqueous solution is an aqueous solution of an acidic, basic or neutral substance, and typical but non-limiting examples thereof are an aqueous hydrogen chloride solution, an aqueous sodium hydroxide solution and an aqueous sodium chloride solution. The main function of the aqueous solution is water, so that no specific requirements are made on the types of acidic, alkaline or neutral substances.

As the preferable technical scheme of the invention, in the catalytic oxidation fluidized bed 5-4, the amount of the steam introduced in the catalytic oxidation process is 0.1-9.9% of the mass of the introduced vanadium oxychloride, the volume fraction of the oxygen content in the introduced clean oxygen-enriched air is 30-95%, and the catalytic oxidation operation temperature is 130-610 ℃.

As a preferred technical scheme of the invention, in the calcining fluidized bed 8-2, the vanadium pentoxide powder is further subjected to fluidized calcining treatment to obtain vanadium pentoxide powder with the purity of more than 4N, the operating temperature of the fluidized calcining is 300-660 ℃, and the average residence time of the powder in the calcining fluidized bed 8-2 is 20-260 min.

The purity of the high-purity vanadium pentoxide powder produced by the method is over 4N (namely 99.99%).

Compared with the prior art, the invention has the following outstanding advantages:

(1) the bed temperature is regulated and controlled by returning the vanadium oxychloride slurry to the boiling chlorination furnace, so that the temperature balance problem of the reaction section is solved, the temperature distribution of the chlorination furnace is more uniform, and the chlorination selectivity is stronger;

(2) by arranging two-stage dust removal and four-stage leaching, the chlorination flue gas is effectively dedusted and condensed, the pipeline blockage is avoided, the production continuity is ensured, and the recovery rate of the vanadium oxytrichloride gas is greatly improved;

(3) pre-removing impurities from the vanadium oxychloride slurry before rectification operation, and removing impurities such as silicon, titanium and the like which are difficult to remove through rectification operation by using a selective hydrolysis method, thereby ensuring the successful preparation of high-purity vanadium oxychloride;

(4) tail gas which is discharged from the catalytic oxidation fluidized bed and is rich in chlorine and hydrogen chloride is treated by a hydrochloric acid condensation absorption tower, hydrochloric acid absorbed by condensation returns to the catalytic oxidation fluidized bed, and the rest chlorine is sent to a chlorine circulating system to realize the recirculation of the chlorine; vanadium oxychloride generates vanadium pentoxide powder and mixed flue gas of chlorine and hydrogen chloride under the catalytic oxidation action of water and oxygen, the condensed and recovered hydrochloric acid returns to the catalytic oxidation fluidized bed, and according to the balance movement, the generation of new hydrogen chloride is inhibited, and the zero emission of hydrogen chloride is realized;

(5) in the process, fluidized beds are selected as reactors in a chlorination working section of industrial-grade vanadium oxide, a catalytic oxidation working section of high-purity vanadium oxychloride, a preheating working section of a catalytic oxidation product and a calcining working section of vanadium pentoxide, so that the process is efficient, energy-saving, high in capacity and convenient for realizing large-scale industrial operation;

the method has the advantages of strong raw material adaptability, good chlorination selectivity, no pollution to wastewater discharge, no discharge of vanadium-containing hydrogen chloride, cyclic utilization of chlorine, low production energy consumption and operation cost, stable product quality and the like, is suitable for large-scale industrial preparation of high-purity vanadium pentoxide powder with the purity of more than 4N, and has good economic benefit and social benefit.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention.

FIG. 1 is a schematic configuration diagram of a system for preparing high-purity vanadium pentoxide powder by an efficient clean chlorination method of the invention.

Reference numerals

1 charging section

1-1 industrial grade vanadium oxide material storehouse 1-2 industrial grade vanadium oxide star batcher

1-3 carbon source bunker 1-4 carbon source star feeder

1-5 mixer 1-6 mixer star-shaped feeder

2 Chlorination section

2-1 boiling chlorination furnace feeder 2-2 boiling chlorination furnace

2-3 chlorinator cyclone separator 2-4 underflow slurry nozzle

2-5 supernatant slurry nozzle 2-6 chlorination residue discharger

3 dust-removing and leaching section

3-1 scraper dust removal tower 3-2 gravity settling tower 3-3 first-stage leaching tower

3-4 slurrying tank 3-5 two-stage leaching tower 3-6 three-stage leaching tower

3-7 four-stage leaching tower 3-8 centrifugal filter 3-9 active carbon adsorption tower

3-10 vanadium oxytrichloride slurry tank

4 purification section

4-1 hydrolysis impurity removal kettle 4-2 distillation kettle 4-3 rectifying tower

4-4 vanadium oxytrichloride condenser 4-5 vanadium oxytrichloride reflux tank 4-6 high-purity vanadium oxytrichloride storage tank

5 catalytic Oxidation section

5-1 vanadium oxytrichloride vaporizer 5-2 vanadium oxytrichloride nozzle

5-3 clean oxygen-enriched air preheater 5-4 catalytic oxidation fluidized bed

5-5 cyclone separator of catalytic oxidation fluidized bed and 5-6 discharger of catalytic oxidation fluidized bed

5-7 hydrochloric acid condensation absorption tower

6 catalytic oxidation product feeding section

6-1 catalytic oxidation product bin 6-2 catalytic oxidation product star-shaped feeder

7 preheating section

7-1 preheating fluidized bed feeder 7-2 preheating fluidized bed

7-3 preheating fluidized bed discharger 7-4 preheating fluidized bed cyclone separator

8 calcination section

8-1 calcining fluidized bed combustor 8-2 calcining fluidized bed

8-3 calcining fluidized bed cyclone separator 8-4 calcining fluidized bed discharger

8-5 high-purity vanadium pentoxide storage bin

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. It should be noted that the examples are only for illustrating the technical solutions of the present invention, and not for limiting the same.

FIG. 1 is a schematic diagram of a system and a method for preparing high-purity vanadium pentoxide powder by an efficient clean chlorination method.

Example 1

With reference to fig. 1, the system for preparing high-purity vanadium pentoxide powder by using a high-efficiency clean chlorination method used in this embodiment includes a charging section 1, a chlorination section 2, a dedusting and leaching section 3, a purification section 4, a catalytic oxidation section 5, a catalytic oxidation product charging section 6, a preheating section 7, and a calcining section 8;

the chlorination working section 2 comprises a boiling chlorination furnace feeder 2-1, a boiling chlorination furnace 2-2, a chlorination furnace cyclone separator 2-3, an underflow slurry nozzle 2-4, an upper clear slurry nozzle 2-5 and a chlorination residue discharger 2-6;

the calcining working section 8 comprises a calcining fluidized bed combustor 8-1, a calcining fluidized bed 8-2, a calcining fluidized bed cyclone separator 8-3, a calcining fluidized bed discharger 8-4 and a high-purity vanadium pentoxide bin 8-5;

a discharge hole at the bottom of the industrial-grade vanadium oxide material bin 1-1 is connected with a feed inlet of an industrial-grade vanadium oxide star-shaped feeder 1-2; a discharge hole at the bottom of the carbon source bin 1-3 is connected with a feed inlet of the carbon source star feeder 1-4; the discharge port of the industrial grade vanadium oxide star feeder 1-2 and the discharge port of the carbon source star feeder 1-4 are connected with the feed port of the mixer 1-5 through pipelines; a discharge hole at the bottom of the mixer 1-5 is connected with a feed inlet of the mixer star-shaped feeder 1-6; the discharge hole of the mixer star-shaped feeder 1-6 is connected with the feed hole of the boiling chlorination furnace feeder 2-1 through a pipeline;

the discharge hole of the boiling chlorination furnace feeder 2-1 is connected with the feed inlet at the upper part of the boiling chlorination furnace 2-2 through a pipeline; an air inlet at the bottom of the boiling chlorination furnace feeder 2-1 is connected with an industrial nitrogen main pipe; the gas inlet at the lower part of the boiling chlorination furnace 2-2 is respectively connected with a chlorine gas source main pipe and an industrial nitrogen main pipe through pipelines; the underflow slurry nozzle 2-4 is positioned at the upper part of the boiling chlorination furnace 2-2; the feed inlets of the underflow slurry nozzles 2 to 4 are connected with the underflow outlets at the lower parts of the vanadium oxychloride slurry tanks 3 to 10 through pipelines; the supernatant slurry nozzle 2-5 is positioned at the lower part of the boiling chlorination furnace 2-2; the feed inlets of the supernatant slurry nozzles 2 to 5 are connected with the supernatant outlets in the middle of the vanadium oxychloride slurry tanks 3 to 10 through pipelines; the chlorination furnace cyclone separator 2-3 is arranged at the top center of the boiling chlorination furnace 2-2; a gas outlet at the top of the chlorination furnace cyclone separator 2-3 is connected with a hot flue gas inlet of the scraper dust removal tower 3-1 through a pipeline; a slag discharge port at the lower part of the boiling chlorination furnace 2-2 is connected with a feed inlet of a chlorination residue discharger 2-6 through a pipeline; the air inlet at the bottom of the chlorination residue slag discharger 2-6 is connected with an industrial nitrogen header pipe;

a vanadium oxychloride slurry inlet at the top of the scraper dust removal tower 3-1 is connected with a slurry outlet of the slurrying tank 3-4 through a pipeline; a vanadium oxychloride slurry inlet at the top of the scraper dedusting tower 3-1 is simultaneously connected with a bottom flow outlet of the distillation kettle 4-2 through a pipeline; the air outlet of the scraper dust removal tower 3-1 is connected with the air inlet of the gravity settling tower 3-2 through a pipeline; the air outlet of the gravity settling tower 3-2 is connected with the air inlet of the first-stage leaching tower 3-3 through a pipeline; a slurry outlet of the first-stage leaching tower 3-3 is connected with a slurry inlet of the slurrying tank 3-4 through a pipeline; a gas outlet of the first-stage leaching tower 3-3 is connected with a gas inlet of the second-stage leaching tower 3-5 through a pipeline; the liquid outlet of the second-stage leaching tower 3-5 is connected with the liquid inlet of the centrifugal filter 3-8 through a pipeline; the gas outlet of the second-stage leaching tower 3-5 is connected with the gas inlet of the third-stage leaching tower 3-6 through a pipeline; the liquid outlet of the third leaching tower 3-6 is connected with the liquid inlet of the centrifugal filter 3-8 through a pipeline; the gas outlet of the third leaching tower 3-6 is connected with the gas inlet of the fourth leaching tower 3-7 through a pipeline; the liquid outlet of the fourth-stage leaching tower 3-7 is connected with the liquid inlet of the centrifugal filter 3-8 through a pipeline; the gas outlet of the fourth-stage leaching tower 3-7 is connected with the gas inlet of the active carbon adsorption tower 3-9 through a pipeline; a supernatant outlet of the centrifugal filter 3-8 is connected with a liquid inlet of the hydrolysis impurity removal kettle 4-1 through a pipeline; the slurry outlet of the centrifugal filter 3-8 is connected with the slurry inlet of the vanadium oxychloride slurry tank 3-10 through a pipeline; the gas outlets of the activated carbon adsorption towers 3 to 9 are connected with the gas inlet of the tail gas treatment system through a pipeline;

a liquid outlet of the hydrolysis impurity removal kettle 4-1 is connected with a liquid inlet of the distillation kettle 4-2 through a pipeline; a gas outlet of the distillation kettle 4-2 is connected with a gas inlet at the bottom of the rectifying tower 4-3 through a pipeline; a reflux port of the distillation kettle 4-2 is connected with a liquid reflux outlet at the bottom of the rectifying tower 4-3 through a pipeline; a gas outlet at the top of the rectifying tower 4-3 is connected with a gas inlet of the vanadium oxytrichloride condenser 4-4 through a pipeline; a liquid outlet of the vanadium oxychloride condenser 4-4 is connected with a liquid inlet of the vanadium oxychloride reflux tank 4-5 through a pipeline; a reflux port of the vanadium oxytrichloride reflux tank 4-5 is connected with a liquid reflux port at the upper part of the rectifying tower 4-3 through a pipeline; the high-purity vanadium oxychloride liquid outlet of the vanadium oxychloride reflux tank 4-5 is connected with the liquid inlet of the high-purity vanadium oxychloride storage tank 4-6 through a pipeline; a liquid outlet at the lower part of the high-purity vanadium trichloride storage tank 4-6 is connected with a liquid inlet of a vanadium trichloride vaporizer 5-1 through a pipeline;

the gas outlet of the vanadium trichloride vaporizer 5-1 is connected with the gas inlet of the vanadium trichloride nozzle 5-2 through a pipeline; the gas inlet of the vanadium oxychloride nozzle 5-2 is simultaneously connected with the clean oxygen-enriched air main pipe; the vanadium oxytrichloride nozzle 5-2 is arranged at the lower position of the middle part of the catalytic oxidation fluidized bed 5-4; the air inlet of the clean oxygen-enriched air preheater 5-3 is connected with a clean oxygen-enriched air main pipe; the air outlet of the clean oxygen-enriched air preheater 5-3 is connected with the fluidizing gas inlet of the catalytic oxidation fluidized bed 5-4 through a pipeline; a clean water inlet of the catalytic oxidation fluidized bed 5-4 is respectively connected with a clean water main pipe and a clean oxygen-enriched air main pipe; a hydrochloric acid inlet of the catalytic oxidation fluidized bed 5-4 is connected with a hydrochloric acid liquid outlet of the hydrochloric acid condensation absorption tower 5-7 through a pipeline; the catalytic oxidation fluidized bed cyclone separator 5-5 is arranged at the center of the top of the catalytic fluidized bed 5-4; a gas outlet of the catalytic oxidation fluidized bed cyclone separator 5-5 is connected with a gas inlet of the hydrochloric acid condensation absorption tower 5-7 through a pipeline; the gas outlets of the hydrochloric acid condensation absorption towers 5 to 7 are connected with the gas inlet of the chlorine gas circulating system; the discharge hole at the bottom of the catalytic oxidation fluidized bed 5-4 is connected with the feed inlet of the catalytic oxidation fluidized bed discharger 5-6 through a pipeline; a loose air inlet at the bottom of the catalytic oxidation fluidized bed discharger 5-6 is connected with a clean oxygen-enriched air main pipe; the discharge hole of the catalytic oxidation fluidized bed discharger 5-6 is connected with the feed hole of the catalytic oxidation product bin 6-1 through a pipeline;

the discharge hole of the catalytic oxidation product bin 6-1 is connected with the feed hole of the catalytic oxidation product star-shaped feeder 6-2; the discharge hole of the catalytic oxidation product star-shaped feeder 6-2 is connected with the feed inlet of the preheating fluidized bed feeder 7-1 through a pipeline;

a loose air inlet at the bottom of the preheating fluidized bed feeder 7-1 is connected with a purified air main pipe; the discharge hole of the preheating fluidized bed feeder 7-1 is connected with the feed inlet of the preheating fluidized bed 7-2 through a pipeline; a high-temperature gas inlet at the bottom of the preheating fluidized bed 7-2 is connected with a gas outlet of the calcining fluidized bed cyclone separator 8-3 through a pipeline; the preheating fluidized bed cyclone separator 7-4 is arranged in the center of the top of the preheating fluidized bed 7-2; the gas outlet of the preheating fluidized bed cyclone separator 7-4 is connected with the gas inlet of the tail gas treatment system through a pipeline; the discharge hole of the preheating fluidized bed 7-2 is connected with the feed inlet of a discharger 7-3 of the preheating fluidized bed through a pipeline; a loose air inlet at the bottom of the preheating fluidized bed discharger 7-3 is connected with a purified air main pipe; the discharge hole of the preheating fluidized bed discharger 7-3 is connected with the feed hole of the calcining fluidized bed 8-2 through a pipeline;

the fuel inlet of the calcining fluidized bed combustor 8-1 is connected with a clean fuel main pipe; a combustion-supporting air inlet of the calcining fluidized bed combustion chamber 8-1 is connected with a purified air main pipe; a high-temperature gas outlet of the calcining fluidized bed combustion chamber 8-1 is connected with a fluidizing gas inlet of the calcining fluidized bed 8-2 through a pipeline; the calcination fluidized bed cyclone separator 8-3 is arranged at the top center of the calcination fluidized bed 8-2, and the discharge hole of the calcination fluidized bed 8-2 is connected with the feed hole of the calcination fluidized bed discharger 8-4 through a pipeline; a loosening air inlet at the bottom of the calcining fluidized bed discharger 8-4 is connected with a purified air main pipe; the discharge hole of the calcining fluidized bed discharger 8-4 is connected with the feed hole of the high-purity vanadium pentoxide bin 8-5 through a pipeline; the bottom of the high-purity vanadium pentoxide bin 8-5 is provided with a discharge outlet with a valve.

Example 2

In this embodiment, the method for preparing high-purity vanadium pentoxide powder by using the system described in embodiment 1 includes the following steps:

industrial vanadium oxide in the industrial vanadium oxidation material bin 1-1 and a carbon source in the carbon source bin 1-3 enter a mixer 1-5 to be mixed through an industrial vanadium oxide star feeder 1-2 and a carbon source star feeder 1-4 respectively; the mixed materials sequentially pass through a mixer star-shaped feeder 1-6 and a boiling chlorination furnace feeder 2-1 to enter a boiling chlorination furnace 2-2; chlorine from a chlorine gas source main pipe and nitrogen from an industrial nitrogen main pipe enter through a gas inlet at the lower part of a boiling chlorination furnace 2-2 to form mixed gas of the chlorine and the nitrogen, so that industrial-grade vanadium oxide and a carbon source are kept fluidized and are subjected to chemical reaction with the industrial-grade vanadium oxide and the carbon source, and the chlorine and the carbon source act together to cause the vanadium oxide and a small amount of impurities to undergo chlorination reaction to form chlorination residues and chlorination flue gas containing vanadium oxychloride; vanadium oxychloride slurry from a vanadium oxychloride slurry tank 3-10 is respectively sprayed into a boiling chlorination furnace 2-2 through an underflow slurry nozzle 2-4 and an supernatant slurry nozzle 2-5, and the temperature in the furnace is adjusted; the chlorination residues are discharged through a residue discharge port at the lower part of the boiling chlorination furnace 2-2 and a chlorination residue discharger 2-6 in sequence; removing dust from the chlorination flue gas by a chlorination furnace cyclone separator 2-3, feeding the chlorination flue gas into a scraper dust removal tower 3-1, and returning the removed dust to the boiling chlorination furnace 2-2;

a slurry nozzle is arranged at the top of the scraper dust removal tower 3-1, and slurry from the slurrying pool 3-4 and bottom flow of the distillation kettle 4-2 enter the scraper dust removal tower 3-1 through the slurry nozzle to cool the chlorination flue gas; the generated dust-collecting slag is discharged through a slag discharge port at the lower part of the scraper dust-removing tower 3-1 and is sent for treatment; the chloridized flue gas after preliminary dust removal and temperature reduction enters a gravity settling tower 3-2 for gravity settling, and the generated dust is discharged through a slag discharge port at the lower part of the gravity settling tower 3-2 and is sent for treatment; the flue gas after the gravity settling treatment is sent to a first-stage leaching tower 3-3 for first-stage leaching, and first-stage leaching slurry is slurried in a slurrying tank 3-4; sending the first-stage leaching tail gas to a second-stage leaching tower 3-5 for second-stage leaching, and sending the second-stage leaching slurry to a centrifugal filter 3-8 for treatment; sending the second-stage leaching tail gas to a third-stage leaching tower 3-6 for third-stage leaching, and sending the third-stage leaching slurry to a centrifugal filter 3-8 for treatment; sending the three-stage leaching tail gas to a four-stage leaching tower 3-7 for four-stage leaching, and sending the four-stage leaching slurry to a centrifugal filter 3-8 for treatment; treating the four-stage leaching tail gas by an activated carbon adsorption tower 3-9, and then sending the tail gas to a tail gas treatment system for treatment; the slurry at the bottom of the centrifugal filter 3-8 is sent to a vanadium oxychloride slurry tank 3-10 for sedimentation treatment, and the supernatant at the top is sent to a hydrolysis impurity removal kettle 4-1 for pre-impurity removal treatment;

feeding the vanadium oxychloride slurry subjected to pre-impurity removal in the hydrolysis impurity removal kettle 4-1 into a distillation kettle 4-2 for distillation, and feeding the distilled gas into a rectifying tower 4-3 for rectification treatment; the evaporation concentrated solution generated by distillation is sprayed into the scraper dust removal tower 3-1 through a nozzle at the top of the scraper dust removal tower 3-1; the high boiling point component in the rectifying tower 4-3 enters a distillation kettle 4-2 through a reflux port; after vanadium oxychloride steam in the rectifying tower 4-3 is condensed to liquid by a vanadium oxychloride condenser 4-4, part of the liquid reflows to the rectifying tower 4-3 through a vanadium oxychloride reflux tank 4-5, and the rest part of the liquid reflows to a high-purity vanadium oxychloride storage tank 4-6;

the high-purity vanadium oxychloride in the high-purity vanadium oxychloride storage tank 4-6 is gasified by a vanadium oxychloride vaporizer 5-1 and then enters a catalytic oxidation fluidized bed 5-4 together with clean oxygen-enriched air through a vanadium oxychloride nozzle 5-2; clean water from a clean water main pipe and clean oxygen-enriched air from a clean oxygen-enriched air main pipe enter a catalytic oxidation fluidized bed 5-4 through a clean water inlet of the catalytic oxidation fluidized bed 5-4; hydrochloric acid from a hydrochloric acid condensation absorption tower 5-7 enters a catalytic oxidation fluidized bed 5-4 through a hydrochloric acid inlet of the catalytic oxidation fluidized bed 5-4; oxygen-enriched air from the clean oxygen-enriched air main pipe is preheated by a clean oxygen-enriched air preheater 5-3 and then enters the catalytic oxidation fluidized bed 5-4 through a fluidizing gas inlet at the bottom of the catalytic oxidation fluidized bed 5-4; vanadium oxychloride in the catalytic oxidation fluidized bed 5-4 forms vanadium pentoxide powder and flue gas containing chlorine and hydrogen chloride under the catalytic oxidation action of clean water and clean oxygen-enriched air; vanadium pentoxide powder enters a catalytic oxidation product bin 6-1 through a catalytic oxidation fluidized bed discharger 5-6; the flue gas for protecting chlorine and hydrogen chloride is dedusted by a catalytic oxidation fluidized bed cyclone separator 5-5 and then enters a hydrochloric acid condensation absorption tower 5-7 for condensation absorption, hydrochloric acid obtained by condensation absorption returns to a catalytic oxidation fluidized bed 5-4, and the rest chlorine is sent to a chlorine circulating system;

vanadium pentoxide powder in the catalytic oxidation product bin 6-1 enters the preheating fluidized bed 7-2 through the catalytic oxidation product star feeder 6-2 and the preheating fluidized bed feeder 7-1; calcining tail gas from the calcining fluidized bed cyclone separator 8-3 enters the preheating fluidized bed 7-2 through a fluidizing gas inlet at the bottom of the preheating fluidized bed 7-2, so that vanadium pentoxide powder is fluidized and heat exchange is realized, and the heat exchange tail gas is dedusted by the preheating fluidized bed cyclone separator 7-4 and then is sent to a tail gas treatment system; the vanadium pentoxide powder preheated by the preheating fluidized bed 7-2 enters the calcining fluidized bed 8-2 through a discharger 7-3 of the preheating fluidized bed;

the purified air from the purified air main pipe and the clean fuel from the clean fuel main pipe are combusted in the combustion chamber 8-1, the generated high-temperature gas enters the calcining fluidized bed 8-2 through a fluidizing gas inlet at the bottom of the calcining fluidized bed 8-2 to maintain the fluidization of the vanadium pentoxide powder, and water and trace volatile substances are removed from the vanadium pentoxide powder to obtain high-purity vanadium pentoxide powder and calcined flue gas; dedusting the calcined flue gas by a calcining fluidized bed cyclone separator 8-3, and then sending the calcined flue gas into a preheating fluidized bed 7-2 to preheat powder; and discharging the high-purity vanadium pentoxide product through a calcinating fluidized bed discharger 8-4 into a high-purity vanadium pentoxide bin 8-5.

Example 3

In the embodiment, the system in embodiment 1 is used to prepare high-purity vanadium pentoxide powder, industrial-grade vanadium pentoxide (with a purity of 98.50%) is used as a raw material, the treatment capacity is 80kg/h, and a high-purity vanadium pentoxide product is prepared through chlorination, dust removal leaching, vanadium oxychloride purification, catalytic oxidation and calcination.

In a boiling chlorination furnace 2-2, the addition amount of petroleum coke in the chlorination reaction process is 30 percent of the mass of industrial-grade vanadium pentoxide powder, the chlorination operation temperature is 600 ℃, the operation gas speed of a fluidization section is 3.00m/s, and the mole fraction of chlorine in a mixed gas of chlorine and nitrogen entering an air chamber is 20 percent; the impurity removing agent added in the hydrolysis impurity removing kettle 4-1 is water, and the using amount of the impurity removing agent is 0.00001 percent of the mass of the vanadium oxychloride slurry; in the catalytic oxidation fluidized bed 5-4, the mass of the water vapor introduced in the catalytic oxidation process is 9.9 percent of that of the vanadium oxychloride, and the operating temperature of the catalytic oxidation is 130 ℃; in a calcination fluidized bed 8-2, under the operating conditions that the calcination operating temperature is 660 ℃ and the average residence time of powder is 20min, the direct yield of vanadium reaches 90 percent, and the purity of a high-purity vanadium pentoxide product reaches 99.995wt percent (4N 5).

Example 4

In the embodiment, the system in the embodiment 1 is used for preparing high-purity vanadium pentoxide powder, industrial-grade vanadium trioxide (with a purity of 97.5%) is used as a raw material, the treatment capacity is 2t/h, and a high-purity vanadium pentoxide product is prepared through chlorination, dust removal leaching, vanadium oxychloride purification, catalytic oxidation and calcination.

In a boiling chlorination furnace 2-2, the addition amount of petroleum coke in the chlorination reaction process is 5% of the mass of industrial-grade vanadium pentoxide powder, the chlorination operation temperature is 290 ℃, the operation gas speed of a fluidization section is 0.05m/s, and the mole fraction of chlorine in a mixed gas of chlorine and nitrogen entering an air chamber is 100%; the impurity removing agent added in the hydrolysis impurity removing kettle 4-1 is aqueous hydrogen chloride solution, and the using amount of the impurity removing agent is 0.1 percent of the mass of the vanadium oxychloride slurry; in the catalytic oxidation fluidized bed 5-4, the mass of the water vapor introduced in the catalytic oxidation process is 0.1 percent of that of the vanadium oxychloride, and the operating temperature of the catalytic oxidation is 610 ℃; in a calcining fluidized bed 8-2, under the operating conditions that the calcining operation temperature is 300 ℃ and the average residence time of powder is 260min, the direct yield of vanadium reaches 93 percent, and the purity of a high-purity vanadium pentoxide product reaches 99.999 percent (5N) by weight.

The invention has not been described in detail and is within the skill of the art.

The present invention may be embodied in many different forms and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A system for preparing high-purity vanadium pentoxide by a high-efficiency clean chlorination method is characterized by comprising a feeding working section (1), a chlorination working section (2), a dedusting and leaching working section (3), a purification working section (4), a catalytic oxidation working section (5), a catalytic oxidation product feeding working section (6), a preheating working section (7) and a calcination working section (8);

the feeding working section (1) comprises an industrial-grade vanadium oxide material bin (1-1), an industrial-grade vanadium oxide star-shaped feeder (1-2), a carbon source bin (1-3), a carbon source star-shaped feeder (1-4), a mixer (1-5) and a mixer star-shaped feeder (1-6);

the chlorination working section (2) comprises a boiling chlorination furnace feeder (2-1), a boiling chlorination furnace (2-2), a chlorination furnace cyclone separator (2-3), an underflow slurry nozzle (2-4), an supernatant slurry nozzle (2-5) and a chlorination residue slag discharger (2-6);

the dust removal leaching working section (3) comprises a scraper dust removal tower (3-1), a gravity settling tower (3-2), a first-stage leaching tower (3-3), a slurrying pool (3-4), a second-stage leaching tower (3-5), a third-stage leaching tower (3-6), a fourth-stage leaching tower (3-7), a centrifugal filter (3-8), an activated carbon adsorption tower (3-9) and a vanadium oxychloride slurry tank (3-10);

the purification working section (4) comprises a hydrolysis impurity removal kettle (4-1), a distillation kettle (4-2), a rectifying tower (4-3), a vanadium oxytrichloride condenser (4-4), a vanadium oxytrichloride reflux tank (4-5) and a high-purity vanadium oxytrichloride storage tank (4-6);

the catalytic oxidation working section (5) comprises a vanadium oxychloride vaporizer (5-1), a vanadium oxychloride nozzle (5-2), a clean oxygen-enriched air preheater (5-3), a catalytic oxidation fluidized bed (5-4) and a catalytic oxidation fluidized bed cyclone separator (5-5); a catalytic oxidation fluidized bed discharger (5-6) and a hydrochloric acid condensation absorption tower (5-7);

the catalytic oxidation product feeding section (6) comprises a catalytic oxidation product bin (6-1) and a catalytic oxidation product star-shaped feeder (6-2);

the preheating working section (7) comprises a preheating fluidized bed feeder (7-1), a preheating fluidized bed (7-2), a preheating fluidized bed discharger (7-3) and a preheating fluidized bed cyclone separator (7-4);

the calcining working section (8) comprises a calcining fluidized bed combustion chamber (8-1), a calcining fluidized bed (8-2), a calcining fluidized bed cyclone separator (8-3), a calcining fluidized bed discharger (8-4) and a high-purity vanadium pentoxide bin (8-5);

a discharge hole at the bottom of the industrial vanadium oxide material bin (1-1) is connected with a feed hole of the industrial vanadium oxide star-shaped feeder (1-2); a discharge hole at the bottom of the carbon source bin (1-3) is connected with a feed inlet of the carbon source star feeder (1-4); the discharge hole of the industrial grade vanadium oxide star feeder (1-2) and the discharge hole of the carbon source star feeder (1-4) are connected with the feed inlet of the mixer (1-5) through pipelines; a discharge hole at the bottom of the mixer (1-5) is connected with a feed inlet of the mixer star-shaped feeder (1-6); the discharge hole of the mixer star-shaped feeder (1-6) is connected with the feed hole of the boiling chlorination furnace feeder (2-1) through a pipeline;

the discharge hole of the boiling chlorination furnace feeder (2-1) is connected with the feed inlet at the upper part of the boiling chlorination furnace (2-2) through a pipeline; an air inlet at the bottom of the boiling chlorination furnace feeder (2-1) is connected with an industrial nitrogen header pipe; the air inlet at the lower part of the boiling chlorination furnace (2-2) is respectively connected with a chlorine gas source main pipe and an industrial nitrogen main pipe through pipelines; the underflow slurry nozzle (2-4) is positioned at the upper part of the boiling chlorination furnace (2-2); the feed inlet of the underflow slurry nozzle (2-4) is connected with the underflow outlet at the lower part of the vanadium oxychloride slurry tank (3-10) through a pipeline; the upper clear slurry nozzle (2-5) is positioned at the lower part of the boiling chlorination furnace (2-2); the feed inlet of the supernatant slurry nozzle (2-5) is connected with the supernatant outlet in the middle of the vanadium oxychloride slurry tank (3-10) through a pipeline; the chlorination furnace cyclone separator (2-3) is arranged at the center of the top of the boiling chlorination furnace (2-2); a gas outlet at the top of the chlorination furnace cyclone separator (2-3) is connected with a hot flue gas inlet of the scraper dust removal tower (3-1) through a pipeline; a slag discharge port at the lower part of the boiling chlorination furnace (2-2) is connected with a feed inlet of the chlorination residue slag discharger (2-6) through a pipeline; the air inlet at the bottom of the chlorination residue discharger (2-6) is connected with an industrial nitrogen header pipe;

a vanadium oxychloride slurry inlet at the top of the scraper dust removal tower (3-1) is connected with a slurry outlet of the slurrying tank (3-4) through a pipeline; the vanadium oxychloride slurry inlet at the top of the scraper dust removal tower (3-1) is simultaneously connected with the bottom flow outlet of the distillation kettle (4-2) through a pipeline; the air outlet of the scraper dust removal tower (3-1) is connected with the air inlet of the gravity settling tower (3-2) through a pipeline; the air outlet of the gravity settling tower (3-2) is connected with the air inlet of the first-stage leaching tower (3-3) through a pipeline; the slurry outlet of the first-stage leaching tower (3-3) is connected with the slurry inlet of the slurrying pool (3-4) through a pipeline; the gas outlet of the first-stage leaching tower (3-3) is connected with the gas inlet of the second-stage leaching tower (3-5) through a pipeline; the liquid outlet of the secondary leaching tower (3-5) is connected with the liquid inlet of the centrifugal filter (3-8) through a pipeline; the gas outlet of the second-stage leaching tower (3-5) is connected with the gas inlet of the third-stage leaching tower (3-6) through a pipeline; the liquid outlet of the third leaching tower (3-6) is connected with the liquid inlet of the centrifugal filter (3-8) through a pipeline; the gas outlet of the third leaching tower (3-6) is connected with the gas inlet of the fourth leaching tower (3-7) through a pipeline; the liquid outlet of the four-stage leaching tower (3-7) is connected with the liquid inlet of the centrifugal filter (3-8) through a pipeline; the gas outlet of the four-stage leaching tower (3-7) is connected with the gas inlet of the activated carbon adsorption tower (3-9) through a pipeline; the supernatant outlet of the centrifugal filter (3-8) is connected with the liquid inlet of the hydrolysis impurity removal kettle (4-1) through a pipeline; the slurry outlet of the centrifugal filter (3-8) is connected with the slurry inlet of the vanadium oxychloride slurry tank (3-10) through a pipeline; the gas outlet of the active carbon adsorption tower (3-9) is connected with the gas inlet of the tail gas treatment system through a pipeline;

the liquid outlet of the hydrolysis impurity removal kettle (4-1) is connected with the liquid inlet of the distillation kettle (4-2) through a pipeline; a gas outlet of the distillation kettle (4-2) is connected with a gas inlet at the bottom of the rectifying tower (4-3) through a pipeline; a reflux port of the distillation kettle (4-2) is connected with a liquid reflux outlet at the bottom of the rectifying tower (4-3) through a pipeline; a gas outlet at the top of the rectifying tower (4-3) is connected with a gas inlet of the vanadium oxytrichloride condenser (4-4) through a pipeline; the liquid outlet of the vanadium oxychloride condenser (4-4) is connected with the liquid inlet of the vanadium oxychloride reflux tank (4-5) through a pipeline; a reflux port of the vanadium oxytrichloride reflux tank (4-5) is connected with a liquid reflux port at the upper part of the rectifying tower (4-3) through a pipeline; a high-purity vanadium oxychloride liquid outlet of the vanadium oxychloride reflux tank (4-5) is connected with a liquid inlet of the high-purity vanadium oxychloride storage tank (4-6) through a pipeline; a liquid outlet at the lower part of the high-purity vanadium trichloride storage tank (4-6) is connected with a liquid inlet of the vanadium trichloride vaporizer (5-1) through a pipeline;

the gas outlet of the vanadium trichloride vaporizer (5-1) is connected with the gas inlet of the vanadium trichloride nozzle (5-2) through a pipeline; the gas inlet of the vanadium oxytrichloride nozzle (5-2) is simultaneously connected with the clean oxygen-enriched air main pipe; the vanadium oxytrichloride nozzle (5-2) is arranged at the lower position of the middle part of the catalytic oxidation fluidized bed (5-4); the air inlet of the clean oxygen-enriched air preheater (5-3) is connected with a clean oxygen-enriched air main pipe; the air outlet of the clean oxygen-enriched air preheater (5-3) is connected with the fluidizing gas inlet of the catalytic oxidation fluidized bed (5-4) through a pipeline; a clean water inlet of the catalytic oxidation fluidized bed (5-4) is respectively connected with a clean water main pipe and a clean oxygen-enriched air main pipe; the hydrochloric acid inlet of the catalytic oxidation fluidized bed (5-4) is connected with the hydrochloric acid liquid outlet of the hydrochloric acid condensation absorption tower (5-7) through a pipeline; the catalytic oxidation fluidized bed cyclone separator (5-5) is arranged at the center of the top of the catalytic oxidation fluidized bed (5-4); the gas outlet of the catalytic oxidation fluidized bed cyclone separator (5-5) is connected with the gas inlet of the hydrochloric acid condensation absorption tower (5-7) through a pipeline; the gas outlet of the hydrochloric acid condensation absorption tower (5-7) is connected with the gas inlet of the chlorine gas circulating system; the discharge hole at the bottom of the catalytic oxidation fluidized bed (5-4) is connected with the feed inlet of the catalytic oxidation fluidized bed discharger (5-6) through a pipeline; a loose air inlet at the bottom of the catalytic oxidation fluidized bed discharger (5-6) is connected with a clean oxygen-enriched air main pipe; the discharge hole of the catalytic oxidation fluidized bed discharger (5-6) is connected with the feed hole of the catalytic oxidation product bin (6-1) through a pipeline;

the discharge hole of the catalytic oxidation product bin (6-1) is connected with the feed hole of the catalytic oxidation product star feeder (6-2); the discharge hole of the catalytic oxidation product star-shaped feeder (6-2) is connected with the feed inlet of the preheating fluidized bed feeder (7-1) through a pipeline;

the loose air inlet at the bottom of the preheating fluidized bed feeder (7-1) is connected with a purified air main pipe; the discharge hole of the preheating fluidized bed feeder (7-1) is connected with the feed hole of the preheating fluidized bed (7-2) through a pipeline; a high-temperature gas inlet at the bottom of the preheating fluidized bed (7-2) is connected with a gas outlet of the calcining fluidized bed cyclone separator (8-3) through a pipeline; the preheating fluidized bed cyclone separator (7-4) is arranged in the center of the top of the preheating fluidized bed (7-2); the air outlet of the preheating fluidized bed cyclone separator (7-4) is connected with the air inlet of the tail gas treatment system through a pipeline; the discharge hole of the preheating fluidized bed (7-2) is connected with the feed inlet of the preheating fluidized bed discharger (7-3) through a pipeline; a loose air inlet at the bottom of the preheating fluidized bed discharger (7-3) is connected with a purified air main pipe; the discharge hole of the preheating fluidized bed discharger (7-3) is connected with the feed hole of the calcining fluidized bed (8-2) through a pipeline;

the fuel inlet of the calcining fluidized bed combustor (8-1) is connected with a clean fuel main pipe; a combustion-supporting air inlet of the calcining fluidized bed combustion chamber (8-1) is connected with a purified air main pipe; the high-temperature gas outlet of the calcining fluidized bed combustor (8-1) is connected with the fluidizing gas inlet of the calcining fluidized bed (8-2) through a pipeline; the calcination fluidized bed cyclone separator (8-3) is arranged at the top center of the calcination fluidized bed (8-2), and the discharge hole of the calcination fluidized bed (8-2) is connected with the feed hole of the calcination fluidized bed discharger (8-4) through a pipeline; a loosening air inlet at the bottom of the calcining fluidized bed discharger (8-4) is connected with a purified air main pipe; the discharge hole of the calcining fluidized bed discharger (8-4) is connected with the feed hole of the high-purity vanadium pentoxide bin (8-5) through a pipeline; the bottom of the high-purity vanadium pentoxide bin (8-5) is provided with a discharge outlet with a valve.

2. The system for preparing high-purity vanadium pentoxide by the high-efficiency clean chlorination method according to claim 1, wherein the scraper dust removal tower (3-1) is a rotary dust removal device provided with a scraper.

3. The method for preparing high-purity vanadium pentoxide powder by using the efficient clean chlorination method based on the system of claim 1 comprises the following steps:

industrial vanadium oxide in the industrial vanadium oxidation material bin (1-1) and a carbon source in the carbon source bin (1-3) simultaneously enter the mixer (1-5) to be mixed through the industrial vanadium oxide star feeder (1-2) and the carbon source star feeder (1-4) respectively; the mixed materials sequentially pass through the mixer star-shaped feeder (1-6) and the boiling chlorination furnace feeder (2-1) to enter the boiling chlorination furnace (2-2); chlorine from a chlorine gas source main pipe and nitrogen from an industrial nitrogen main pipe enter through a gas inlet at the lower part of the boiling chlorination furnace (2-2) to form a mixed gas of the chlorine and the nitrogen, so that industrial-grade vanadium oxide and a carbon source are maintained in fluidization and are subjected to chemical reaction with the industrial-grade vanadium oxide and the carbon source, and the chlorine and the carbon source act together to cause the vanadium oxide and impurities to undergo chlorination reaction to form chlorination residues and chlorination flue gas containing vanadium oxychloride; vanadium oxychloride slurry from the vanadium oxychloride slurry tank (3-10) is respectively sprayed into the boiling chlorination furnace (2-2) through the underflow slurry nozzle (2-4) and the supernatant slurry nozzle (2-5), and the temperature in the furnace is adjusted; the chlorination residues are discharged through a residue discharge port at the lower part of the boiling chlorination furnace (2-2) and the chlorination residue discharger (2-6) in sequence; removing dust from the chlorination flue gas by the chlorination furnace cyclone separator (2-3), feeding the chlorination flue gas into the scraper dust removal tower (3-1), and returning the removed dust to the boiling chlorination furnace (2-2);

a slurry nozzle is arranged at the top of the scraper dust removal tower (3-1), and slurry from the slurrying pool (3-4) and the bottom flow of the distillation kettle (4-2) enter the scraper dust removal tower (3-1) through the slurry nozzle to cool chlorination flue gas; the generated dust-collecting slag is discharged through a slag discharge port at the lower part of the scraper dust-removing tower (3-1) and is sent for treatment; the chloridized flue gas after primary dedusting and cooling enters the gravity settling tower (3-2) for gravity settling, and the generated dust is discharged through a slag discharge port at the lower part of the gravity settling tower (3-2) and is sent for treatment; the flue gas after the gravity settling treatment is sent to the first-stage leaching tower (3-3) for first-stage leaching, and first-stage leaching slurry is slurried in the slurrying tank (3-4); sending the first-stage leaching tail gas to the second-stage leaching tower (3-5) for second-stage leaching, and sending the second-stage leaching slurry to the centrifugal filter (3-8) for treatment; sending the second-stage leaching tail gas to the third-stage leaching tower (3-6) for third-stage leaching, and sending the third-stage leaching slurry to the centrifugal filter (3-8) for treatment; sending the three-stage leaching tail gas to the four-stage leaching tower (3-7) for four-stage leaching, and sending the four-stage leaching slurry to the centrifugal filter (3-8) for treatment; the four-stage leaching tail gas is treated by the activated carbon adsorption tower (3-9) and then sent to a tail gas treatment system for treatment; slurry at the bottom of the centrifugal filter (3-8) is sent to the vanadium oxychloride slurry tank (3-10) for sedimentation treatment, and supernatant at the top is sent to the hydrolysis impurity removal kettle (4-1) for pre-impurity removal treatment;

feeding the vanadium oxychloride slurry subjected to pre-impurity removal in the hydrolysis impurity removal kettle (4-1) into the distillation kettle (4-2) for distillation, and feeding the distilled gas into the rectifying tower (4-3) for rectification; the evaporation concentrated solution generated by distillation is sprayed into the scraper dust removal tower (3-1) through a nozzle at the top of the scraper dust removal tower (3-1); high boiling point components in the rectifying tower (4-3) enter the distillation kettle (4-2) through a reflux port; after vanadium oxychloride steam in the rectifying tower (4-3) is condensed to liquid by the vanadium oxychloride condenser (4-4), part of the vanadium oxychloride steam flows back to the rectifying tower (4-3) through the vanadium oxychloride reflux tank (4-5), and the rest of the vanadium oxychloride steam enters the high-purity vanadium oxychloride storage tank (4-6);

the high-purity vanadium oxychloride in the high-purity vanadium oxychloride storage tank (4-6) is gasified by the vanadium oxychloride vaporizer (5-1), and then enters the catalytic oxidation fluidized bed (5-4) together with clean oxygen-enriched air through the vanadium oxychloride nozzle (5-2); clean water from a clean water main and clean oxygen-enriched air from a clean oxygen-enriched air main enter the catalytic oxidation fluidized bed (5-4) together through a clean water inlet of the catalytic oxidation fluidized bed (5-4); hydrochloric acid from the hydrochloric acid condensation absorption tower (5-7) enters the catalytic oxidation fluidized bed (5-4) through a hydrochloric acid inlet of the catalytic oxidation fluidized bed (5-4); the clean oxygen-enriched air from the clean oxygen-enriched air main pipe is preheated by the clean oxygen-enriched air preheater (5-3) and then enters the catalytic oxidation fluidized bed (5-4) through a fluidizing gas inlet at the bottom of the catalytic oxidation fluidized bed (5-4); vanadium oxychloride in the catalytic oxidation fluidized bed (5-4) forms vanadium pentoxide powder and flue gas containing chlorine and hydrogen chloride under the catalytic oxidation action of clean water and clean oxygen-enriched air; vanadium pentoxide powder enters the catalytic oxidation product bin (6-1) through the catalytic oxidation fluidized bed discharger (5-6); flue gas containing chlorine and hydrogen chloride is dedusted by the catalytic oxidation fluidized bed cyclone separator (5-5), enters the hydrochloric acid condensation absorption tower (5-7) for condensation absorption, hydrochloric acid obtained by condensation absorption returns to the catalytic oxidation fluidized bed (5-4), and the rest chlorine is sent to a chlorine circulating system;

vanadium pentoxide powder in the catalytic oxidation product bin (6-1) enters the preheating fluidized bed (7-2) through the catalytic oxidation product star feeder (6-2) and the preheating fluidized bed feeder (7-1); calcining tail gas from the calcining fluidized bed cyclone separator (8-3) enters the preheating fluidized bed (7-2) through a fluidizing gas inlet at the bottom of the preheating fluidized bed (7-2) to maintain the fluidization of vanadium pentoxide powder and realize heat exchange, and the heat exchange tail gas is sent to a tail gas treatment system after being dedusted by the preheating fluidized bed cyclone separator (7-4); vanadium pentoxide powder preheated by the preheating fluidized bed (7-2) enters the calcining fluidized bed (8-2) through the discharger (7-3) of the preheating fluidized bed;

the purified air from the purified air main pipe and the clean fuel from the clean fuel main pipe are combusted in the combustion chamber (8-1), the generated high-temperature gas enters the calcining fluidized bed (8-2) through a fluidizing gas inlet at the bottom of the calcining fluidized bed (8-2) to maintain the fluidization of the vanadium pentoxide powder, and water and volatile substances are removed from the vanadium pentoxide powder to obtain high-purity vanadium pentoxide powder and calcined flue gas; the calcining flue gas is dedusted by the calcining fluidized bed cyclone separator (8-3) and then is sent to the preheating fluidized bed (7-2) for preheating powder; and discharging a high-purity vanadium pentoxide product through the calcining fluidized bed discharger (8-4) and feeding the high-purity vanadium pentoxide product into the high-purity vanadium pentoxide storage bin (8-5).

4. The method for preparing high-purity vanadium pentoxide powder by using the efficient clean chlorination method according to claim 3, wherein the industrial-grade vanadium oxide in the industrial-grade vanadium oxidation material bin (1-1) is industrial-grade vanadium trioxide, vanadium tetraoxide, vanadium pentoxide or a mixture thereof; the carbon source in the carbon source bin (1-3) refers to any one or a combination of at least two of activated carbon, metallurgical coke, petroleum coke or coal powder; the addition amount of the carbon source in the chlorination reaction process is 5-30% of the mass of the industrial-grade vanadium oxide.

5. The method for preparing high-purity vanadium pentoxide powder by the efficient clean chlorination method according to claim 3, wherein the operating temperature of the chlorination reaction in the boiling chlorination furnace (2-2) is 290-600 ℃; the operating gas velocity of the fluidization section is 0.05-3.00 m/s, and the mole fraction of chlorine in the mixed gas of chlorine and nitrogen entering the air chamber of the boiling chlorination furnace (2-2) is 20-100%.

6. The method for preparing high-purity vanadium pentoxide powder by using the high-efficiency clean chlorination method according to claim 3, wherein the preliminary impurity removal in the hydrolysis impurity removal kettle (4-1) is to remove impurities titanium and silicon in the vanadium oxychloride slurry by using a selective hydrolysis method, the impurity removal agent is water or an aqueous solution, and the dosage of the impurity removal agent is 0.00001-0.1% of the mass of the vanadium oxychloride slurry.

7. The method for preparing high-purity vanadium pentoxide powder by the high-efficiency clean chlorination method according to claim 3, wherein in the catalytic oxidation fluidized bed (5-4), the amount of steam introduced in the catalytic oxidation process is 0.1-9.9% of the mass of the introduced vanadium oxychloride, the volume fraction of oxygen in the introduced clean oxygen-enriched air is 30-95%, and the catalytic oxidation operation temperature is 130-610 ℃.

8. The method for preparing high-purity vanadium pentoxide powder by the efficient clean chlorination method according to claim 3, wherein the vanadium pentoxide powder is further subjected to fluidized calcination treatment in the calcination fluidized bed (8-2) to obtain vanadium pentoxide powder with the purity of more than 4N, the operation temperature of the fluidized calcination is 300-660 ℃, and the average residence time of powder in the calcination fluidized bed (8-2) is 20-260 min.