CN109835950B

CN109835950B - System and method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources

Info

Publication number: CN109835950B
Application number: CN201711189974.9A
Authority: CN
Inventors: 朱庆山; 杨海涛; 范川林
Original assignee: Institute of Process Engineering of CAS
Current assignee: Institute of Process Engineering of CAS
Priority date: 2017-11-24
Filing date: 2017-11-24
Publication date: 2020-04-24
Anticipated expiration: 2037-11-24
Also published as: CN109835950A

Abstract

The invention discloses a system and a method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources. The vanadium resource enters a chlorination furnace for selective chlorination through the pretreatment processes of granulation, oxidation, crushing, screening and the like, vanadium in the vanadium resource is converted into gaseous vanadium oxychloride, most of impurities such as iron, chromium, calcium, phosphorus, manganese, titanium, silicon and the like in the vanadium resource are left in chlorination residues, and effective separation of vanadium and other impurities is realized. The high-purity vanadium pentoxide is prepared by sequentially carrying out the procedures of dust removal, leaching, sedimentation, rectification, purification, catalytic oxidation and the like on gaseous vanadium oxychloride. And (3) sequentially carrying out the processes of waste heat recovery, washing dechlorination, settling separation, filtering washing and the like on the chlorination residues to obtain filter residues and washing liquid, returning the filter residues to ironmaking, and evaporating and crystallizing the washing liquid to obtain chlorine salt. The invention realizes the clean and comprehensive utilization of vanadium resources, effectively utilizes the sensible heat of high-temperature flue gas and high-temperature chlorination residues of the chlorination furnace, and achieves the purposes of energy conservation and consumption reduction.

Description

System and method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources

Technical Field

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

Background

Vanadium pentoxide is an important metallurgical chemical material and is mainly used for producing alloy steel by using an iron-based alloy additive all the time. With the rapid development of industrial technologies in recent years, the application proportion of vanadium pentoxide in the fields of aeroalloys, energy storage materials, petrochemical catalysts and the like is gradually increased. In particular, the rapid development of the industries of energy storage materials (electrolyte of all-vanadium redox flow batteries and lithium vanadate anode materials) and high-performance aviation alloys (vanadium-aluminum alloys and vanadium-titanium alloys) generates huge demands on high-quality and high-purity vanadium pentoxide.

The vanadium titano-magnetite is the main raw material for producing vanadium pentoxide. At present, vanadium-containing molten iron is obtained industrially by reduction smelting, and vanadium slag is obtained by further converting; preparing industrial-grade vanadium pentoxide from the vanadium slag through a process of sodium roasting-leaching-vanadium precipitation-calcining decomposition; and further removing impurities by repeatedly precipitating the industrial-grade vanadium pentoxide to improve the purity. The process mainly has the following outstanding problems: (1) the process is long, the energy consumption is high, and the production cost is high; (2) the recovery rate of vanadium is low, and the recovery rate from vanadium slag to vanadium oxide products is less than 80 percent; (3) vanadium extraction residues are difficult to treat, and a large amount of sodium salt is introduced by sodium salt roasting, so that the direct return of the residues to a blast furnace for ironmaking is limited; (4) the environmental problem is prominent, and a large amount of ammonia nitrogen wastewater containing various harmful metal ions and sodium sulfate is generated in the leaching-vanadium precipitation process, thereby causing serious influence on the ecological environment. Therefore, the development of a new technology for producing high-purity vanadium pentoxide cleanly and efficiently is a necessary way for realizing the sustainable development of the vanadium industry.

The process for extracting vanadium by chlorination draws people's attention due to the characteristics of strong chlorination selectivity and easy rectification and purification. For example, chinese patent CN101709388B discloses a process for separating vanadium by chloridizing and roasting vanadium slag, which comprises mixing vanadium slag oxidizing and roasting material, solid chlorinating agent and carbonaceous reducing agent in a certain proportion, pelletizing, and roasting in a rotary kiln to volatilize vanadium in the form of chloride, thereby achieving the purpose of separating and extracting vanadium. The process of adopting the solid chlorinating agent and combining the rotary kiln for roasting has the problems of low efficiency and being not beneficial to large-scale operation. The process does not relate to a method for preparing vanadium pentoxide by vanadium oxychloride, and is not a complete technology for preparing vanadium pentoxide. Chinese patent CN101845552B discloses a method for recovering valuable elements from vanadium slag through gradient chlorination, wherein vanadium slag, solid salt and simple substance carbon are uniformly mixed, and chlorine gas is introduced at different temperatures to perform chlorination of vanadium, iron, chromium and silicon in sequence so as to achieve the purpose of separating and enriching the elements. The process simultaneously adopts a solid chlorinating agent and a gas chlorinating agent, and has a complex flow. The process does not relate to a method for preparing vanadium pentoxide by vanadium oxychloride or vanadium tetrachloride, and is not a complete technology for preparing vanadium pentoxide. Chinese patent CN103130279B discloses a method for preparing vanadium pentoxide by using vanadium-containing substances such as vanadium slag and the like as raw materials and adopting a chlorination method, wherein vanadium pentoxide is prepared by carbon chlorination (adopting a solid chlorinating agent or a gas chlorinating agent) of the vanadium-containing substances, rectification purification, liquid phase hydrolysis or ammonium salt precipitation, drying or calcination. The process only provides a principle process flow of chlorination vanadium extraction, and does not provide a technical scheme with strong implementation performance on key problems of selective chlorination of vanadium slag, efficient preparation of vanadium pentoxide from chloride and the like. Moreover, the technological process of preparing vanadium pentoxide by "carbo-chlorination-purification-liquid phase hydrolysis or ammonium salt precipitation-calcination" was proposed by researchers at the state university of Iowa in the United states as early as 60 s in the 20 th century (Journal of the Less-Common Metals,1960,2: 29-35). Chinese patent CN105986126B discloses a system and a method for efficiently chloridizing and extracting vanadium from vanadium slag, and vanadium pentoxide is prepared by the technological process of carbon-matching chlorination of vanadium slag, distillation purification and gas phase hydrolysis. The process adopts a boiling chlorination technology, and has great technical advantages compared with chlorination by a solid chlorinating agent. And the vanadium pentoxide is prepared from the vanadium oxychloride by adopting a gas-phase hydrolysis process, compared with liquid-phase hydrolysis or ammonium salt precipitation, the wastewater amount is greatly reduced, and the obvious technical advantage is presented. However, the vanadium slag in the process directly enters a chlorination furnace without pretreatment, so that the selectivity of vanadium chlorination is reduced, a large amount of harmful elements are converted into chlorides, and the cost of subsequent distillation purification and chlorination residue treatment is greatly increased. The chlorination flue gas volatilized from the chlorination furnace is not subjected to dust removal treatment and is directly subjected to heat exchange, so that a pipeline is blocked, and the production is seriously influenced. The gas phase hydrolysis process can generate a large amount of vanadium-containing hydrochloric acid, and the environmental protection cost is increased. And the heat balance of the chlorination furnace and the sensible heat of the high-temperature chlorination flue gas and the chlorination residues are not well utilized.

In summary, the main outstanding problems of the existing vanadium extraction technology by chlorination include: (1) the chlorination selectivity is poor, and when vanadium element in vanadium resources is chlorinated, chlorination of other iron, chromium, calcium, phosphorus, titanium and silicon can be caused, so that rectification purification and chlorination residue treatment are difficult; (2) the chlorination roasting of vanadium resource belongs to a strong heat release process, and the heat generated by chlorination reaction can meet the preheating of solid and gas reaction materials and still needs heat exchange and temperature reduction treatment. The generated high-temperature flue gas and the high-temperature chlorination residues can be subjected to subsequent treatment only by cooling. Distillation and waste water crystallization require a large amount of energy consumption. The energy of the front and the back procedures can not be effectively utilized coordinately, so that the energy consumption is greatly improved, and the production cost is increased; (3) the preparation of industrial vanadium product vanadium pentoxide from vanadium chloride (vanadium oxychloride) lacks a high-efficiency clean technical route, because vanadium has higher solubility in hydrochloric acid solution, direct liquid-phase hydrolysis can cause the recovery rate of vanadium to be too low, and ammonium salt precipitation can improve the precipitation rate of vanadium, but can generate a large amount of ammonia nitrogen wastewater; although the gas phase hydrolysis process avoids the generation of ammonia nitrogen wastewater, a large amount of vanadium-containing hydrochloric acid is brought, and the environmental problem is prominent; and so on. These problems are important reasons that the existing vanadium resource chlorination vanadium extraction process cannot be applied in large scale.

Therefore, the method improves the chlorination selectivity, realizes temperature regulation and control in the chlorination process and comprehensive utilization of heat in the whole process, solves the problem of efficiently preparing vanadium pentoxide by vanadium oxychloride, and is the key point of large-scale application of the vanadium resource chlorination process.

Disclosure of Invention

Aiming at the problems, the invention provides a system and a method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources, so as to realize high-efficiency selective chlorination of the vanadium resources, recovery and utilization of sensible heat of high-temperature chlorination flue gas, recovery and utilization of sensible heat of high-temperature chlorination residues, dechlorination treatment of the chlorination residues, and preparation of the high-purity vanadium pentoxide by catalytic oxidation of vanadium oxychloride.

In order to achieve the purposes, the invention adopts the following technical scheme:

the system for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources comprises a material preparation working section 1, a material mixing working section 2, a chlorination dust collection working section 3, a leaching and settling working section 4, a refining working section 5, a powder making working section 6, a waste heat utilization working section 7 and a residue treatment working section 8;

the material preparation working section 1 comprises a vanadium resource bin 1-1, a vanadium resource screw feeder 1-2, a disc granulator 1-3, an oxidation roasting rotary kiln 1-4, a pair of roller machines 1-5, a coarse grain sieving machine 1-6 and a fine grain sieving machine 1-7;

the material mixing working section 2 comprises a screening vanadium resource bin 2-1, a screening vanadium resource feeder 2-2, a carbon source bin 2-3, a carbon source feeder 2-4 and a fluidized bed mixer 2-5;

the chlorination dust collection working section 3 comprises a chlorination furnace 3-1, a chlorination furnace heat exchanger 3-2, a dust collection tower 3-3 and a dust collection tower heat exchanger 3-4;

the leaching and settling section 4 comprises a leaching tower 4-1, a slurry pump 4-2, a leaching tower heat exchanger 4-3, a drip catcher 4-4 and a leaching slurry settling tank 4-5;

the refining section 5 comprises a rectifying tower 5-1, a reboiler 5-2, a reboiler heat exchanger 5-3, a high-purity vanadium oxychloride condenser 5-4 and a high-purity vanadium oxychloride storage tank 5-5;

the powder preparation working section 6 comprises a vaporizer 6-1, a powder preparation reactor 6-2, a powder preparation heat exchanger 6-3, a powder preparation soft water storage tank 6-4, a powder preparation soft water circulating pump 6-5, a high-purity vanadium storage bin 6-6 and a high-purity vanadium screw feeder 6-7;

the waste heat utilization section 7 comprises a waste heat recovery fluidized bed 7-1, a waste heat recovery fluidized bed heat exchanger 7-2, a waste heat recovery soft water storage tank 7-3 and a waste heat recovery circulating pump 7-4;

the residue treatment section 8 comprises a residue washing stirring kettle 8-1, a residue slurry settling tank 8-2, a residue washing filter 8-3, an evaporation crystallizer 8-4, a crystallization heat exchanger 8-5, an evaporation water condenser 8-6 and a crystallized salt washing filter 8-7;

a discharge hole at the bottom of the vanadium resource bin 1-1 is connected with a feed inlet of the vanadium resource screw feeder 1-2; the discharge hole of the vanadium resource screw feeder 1-2 is connected with the feed inlet of the disc granulator 1-3 through a pipeline; the feed back port of the disc granulator 1-3 is connected with the fine powder outlet of the fine particle sieving machine 1-7 through a pipeline; the discharge hole of the disc granulator 1-3 is connected with the feed hole of the oxidizing roasting rotary kiln 1-4 through a pipeline; an air inlet is formed in the upper part of the oxidizing roasting rotary kiln 1-4; the discharge hole of the oxidizing roasting rotary kiln 1-4 is connected with the feed hole of the double-roller machine 1-5; the feed inlets of the double-roller machines 1-5 are simultaneously connected with the coarse grain outlets of the coarse grain sieving machines 1-6 through pipelines; the discharge hole of the double-roller machine 1-5 is connected with the feed hole of the coarse grain sieving machine 1-6 through a pipeline; a fine particle outlet of the coarse particle sieving machine 1-6 is connected with a feeding hole of the fine particle sieving machine 1-7 through a pipeline; a fine grain outlet of the fine grain sieving machine 1-7 is connected with a feed inlet of the vanadium sieving resource bin 2-1 through a pipeline;

the discharge hole of the screening vanadium resource bin 2-1 is connected with the feed hole of the screening vanadium resource feeder 2-2; a discharge hole of the carbon source bin 2-3 is connected with a feed hole of the carbon source feeder 2-4; the discharge hole of the screening vanadium resource feeder 2-2 and the discharge hole of the carbon source feeder 2-4 are both connected with the feed inlet of the fluidized bed mixer 2-5 through pipelines; the loosening air inlet of the fluidized bed mixer 2-5 is connected with a nitrogen header pipe through a pipeline; the discharge hole of the fluidized bed mixer 2-5 is connected with the feed inlet of the chlorination furnace 3-1 through a pipeline;

the air inlet of the chlorination furnace 3-1 is respectively connected with a chlorine gas main pipe, a circulating chlorine gas main pipe and a nitrogen gas main pipe; the middle upper part of the chlorination furnace 3-2 is provided with the chlorination furnace heat exchanger 3-2; a slurry inlet at the top of the chlorination furnace 3-2 is connected with a kettle bottom liquid outlet of the reboiler 5-2 through a pipeline; the flue gas outlet of the chlorination furnace 3-2 is connected with the flue gas inlet of the dust collection tower 3-3 through a pipeline; the slag discharge port of the chlorination furnace 3-1 is connected with the feed inlet of the preheating recovery fluidized bed 7-1 through a pipeline; a slurry inlet at the top of the dust collection tower 3-3 is connected with a kettle bottom liquid outlet of the reboiler 5-2 through a pipeline; the slag discharge port of the dust collection tower 3-3 is connected with the feed port of the preheating recovery fluidized bed 7-1 through a pipeline; the gas outlet of the dust collecting tower 3-3 is connected with the gas inlet of the leaching tower 4-1 through a pipeline; a dust collecting tower heat exchanger 3-4 is arranged in the middle of the dust collecting tower 3-3; a heat flow outlet of the dust collection tower heat exchanger 3-4 is connected with a heat flow inlet of the reboiler 5-3 through a pipeline; the heat flow inlet of the dust collection tower heat exchanger 3-4 is connected with the heat flow outlet of the powder-making soft water circulating pump 6-5 through a pipeline;

the bottom of the leaching tower 4-1 is provided with the slurry pump 4-2; the top of the leaching tower 4-1 is provided with the leaching tower heat exchanger 4-3; a gas outlet of the leaching tower 4-1 is connected with a gas inlet of the drip catcher 4-4 through a pipeline; the tail gas outlet of the drip catcher 4-4 is connected with the gas inlet of the environmental workshop through a pipeline; the bottom liquid outlet of the leaching tower 4-1 and the bottom liquid outlet of the drip catcher 4-4 are both connected with the feed inlet of the leaching slurry settling tank 4-5 through pipelines; a slurry outlet of the leaching slurry settling tank 4-5 is connected with the chlorination furnace 3-1 and a slurry inlet at the top of the dust collection tower 3-3 through pipelines; the supernatant outlet of the leaching slurry settling tank 4-5 is connected with the liquid inlet of the rectifying tower 5-1 through a pipeline;

a gas inlet of the rectifying tower 5-1 is connected with a gas outlet of the reboiler 5-2 through a pipeline; the tower bottom liquid outlet of the rectifying tower 5-1 is connected with the reflux port of the reboiler 5-2 through a pipeline; the heat flow outlet of the reboiler heat exchanger 5-3 is connected with the heat flow inlet of the pulverizing heat exchanger 6-3 through a pipeline; the high-purity vanadium oxychloride gas outlet of the rectifying tower 5-1 is connected with the gas inlet of the high-purity vanadium oxychloride condenser 5-4 through a pipeline; the liquid outlet of the high-purity vanadium trichloride condenser 5-4 is connected with the liquid inlet of the high-purity vanadium trichloride storage tank 5-5 through a pipeline; the liquid outlet of the high-purity vanadium oxytrichloride storage tank 5-5 is connected with the feed inlet of the powder preparation reactor 6-2 through a pipeline;

the air inlet of the vaporizer 6-1 is respectively connected with the oxygen-enriched air purifying main pipe and the ultrapure water main pipe through pipelines; the gas outlet of the vaporizer 6-1 is connected with the gas inlet of the pulverizing reactor 6-2 through a pipeline; the reaction tail gas outlet of the powder preparation reactor 6-2 is connected with the gas inlet of the chlorine circulating system through a pipeline; the powder making heat exchanger 6-3 is positioned in the middle of the powder making reactor 6-2; the heat flow outlet of the powder-making heat exchanger 6-3 is connected with the inlet of the powder-making soft water storage tank 6-4 through a pipeline; the water outlet of the powder making soft water storage tank 6-4 is connected with the water inlet of the powder making soft water circulating pump 6-5 through a pipeline; the discharge hole of the powder preparation reactor 6-2 is connected with the feed hole of the high-purity vanadium bunker 6-6 through a pipeline; the discharge hole of the high-purity vanadium bunker 6-6 is connected with the feed hole of the high-purity vanadium screw feeder 6-7;

the bottom air inlet of the waste heat recovery fluidized bed 7-1 is connected with a nitrogen header pipe; a tail gas outlet is formed in the top of the waste heat recovery fluidized bed 7-1; the residue discharge port of the waste heat recovery fluidized bed 7-1 is connected with the feed inlet of the residue washing stirring kettle 8-1 through a pipeline; the middle part of the waste heat recovery fluidized bed 7-1 is provided with the waste heat recovery fluidized bed heat exchanger 7-2; a heat flow outlet of the waste heat recovery fluidized bed heat exchanger 7-2 is connected with a heat flow inlet of the crystallization heat exchanger 8-5 through a pipeline; the heat flow outlet of the crystallization heat exchanger 8-5 is connected with the heat flow inlet of the waste heat recovery soft water storage tank 7-3 through a pipeline; the heat flow outlet of the waste heat recovery soft water storage tank 7-3 is connected with the inlet of the waste heat recovery circulating pump 7-4 through a pipeline; a heat flow outlet of the waste heat recovery circulating pump 7-4 is connected with a heat flow inlet of the waste heat recovery fluidized bed heat exchanger 7-2 through a pipeline;

the water inlet of the residue washing stirring kettle 8-1 is connected with a process water main pipe; the water inlet of the residue washing stirring kettle 8-1 is simultaneously connected with the washing water outlet of the crystallized salt washing filter 8-7 through a pipeline; the slurry outlet of the residue washing and stirring kettle 8-1 is connected with the feed inlet of the residue slurry settling tank 8-2 through a pipeline; a supernatant outlet of the residue slurry settling tank 8-2 is connected with a liquid inlet of the evaporative crystallizer 8-4 through a pipeline; the slurry outlet of the residue slurry settling tank 8-2 is connected with the slurry inlet of the residue washing filter 8-3 through a pipeline; a washing water inlet of the residue washing filter 8-3 is connected with a process water main pipe; the residue washing filter 8-3 is provided with a residue discharge port; a washing liquid outlet of the residue washing filter 8-3 is connected with a liquid inlet of the evaporative crystallizer 8-4 through a pipeline; a water vapor outlet of the evaporative crystallizer 8-4 is connected with a gas inlet of the evaporative water condenser 8-6 through a pipeline; the liquid outlet of the evaporation water condenser 8-6 is connected with a process water main pipe; the middle part of the evaporative crystallizer 8-4 is provided with the crystallization heat exchanger 8-5; a crystallized salt outlet of the evaporative crystallizer 8-4 is connected with a crystallized salt inlet of the crystallized salt washing filter 8-7 through a pipeline; the washing water inlet of the crystallized salt washing filter 8-7 is connected with the process water main pipe through a pipeline; the crystallized salt washing filter 8-7 is provided with a chlorine salt product outlet; and a washing liquid outlet of the crystallized salt washing filter 8-7 is connected with a liquid inlet of the residue washing stirring kettle 8-1 through a pipeline.

The method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources based on the system comprises the following steps:

the vanadium resource in the vanadium resource bin 1-1 enters the disc granulator 1-3 through the vanadium resource screw feeder 1-2 for granulation treatment; after the vanadium resource after granulation treatment is sequentially subjected to ore phase reforming by the oxidizing roasting rotary kiln 1-4, crushing by the double-roller machine 1-5, screening by the coarse grain screening machine 1-6 and the fine grain screening machine 1-7, and then entering the screening vanadium resource bin 2-1; the operating temperature of the oxidizing roasting rotary kiln 1-4 is 400-1000 ℃; the vanadium resource in the screening vanadium resource bin 2-1 and the carbon source in the carbon source bin 2-3 simultaneously enter the fluidized bed mixer 2-5 through the screening vanadium resource feeder 2-2 and the carbon source feeder 2-4 respectively; after mixing, the mixture enters the chlorination furnace 3-1; the carbon content is 5-25% of the mass of the screened vanadium resource;

chlorine from the chlorine main pipe, nitrogen from the nitrogen main pipe and chlorine from the circulating chlorine main pipe enter through an air inlet at the bottom of the chlorination furnace 3-1; maintaining the vanadium resource powder and the carbon source in fluidization and carrying out chemical reaction; enabling vanadium and partial impurities in the vanadium resource to be chlorinated to form smoke rich in vanadium oxychloride and chlorination residues; the chlorination operation temperature is 280-950 ℃; the carbon-blending chlorination of vanadium resources is a strong heat release process, and in order to prevent the temperature from being too high, the middle part of the chlorination furnace 3-1 is provided with the chlorination furnace heat exchanger 3-2 for removing redundant heat; simultaneously, kettle bottom liquid from the reboiler 5-2 is sprayed from the top of the chlorination furnace 3-1 to assist the heat exchange of the chlorination furnace and prevent the temperature from being overhigh; the chlorination residue is sent to the waste heat recovery fluidized bed 7-1; delivering the smoke rich in vanadium oxychloride into the dust collecting tower 3-3 for dust removal treatment; spraying the slurry from the leaching slurry settling tank 4-5 into the dust collecting tower 3-3 from an inlet at the top of the dust collecting tower, and removing solid dust in the slurry while cooling the vanadium oxychloride flue gas; the dust in the dust collecting tower 3-3 is sent to the waste heat recovery fluidized bed 7-1 for treatment; the dust collecting tower heat exchanger 3-4 is used for recycling sensible heat of high-temperature flue gas in the dust collecting tower 3-3, and heat is provided for the reboiler 5-2 and the pulverizing reactor 6-2 through the reboiler heat exchanger 5-3 and the pulverizing heat exchanger 6-3 respectively, so that energy conservation and consumption reduction are realized;

sending the vanadium oxychloride gas subjected to dust removal by the dust collection tower 3-3 to the leaching tower 4-1 for leaching, and sending leached tail gas to an environment-friendly workshop for treatment after liquid drops are recovered by the drip catcher 4-4; sending the vanadium oxychloride slurry in the leaching tower 4-1 and the vanadium oxychloride liquid recovered by the drip catcher 4-4 to the leaching slurry settling tower 4-5 for treatment; sending the supernatant of the leaching slurry settling tank 4-5 to the rectifying tower 5-1 for rectification and purification to obtain high-purity vanadium oxychloride steam, and sending the high-purity vanadium oxychloride steam to the high-purity vanadium oxychloride storage tank 5-5 for storage after the high-purity vanadium oxychloride steam is condensed by the high-purity vanadium oxychloride condenser 5-4; ultrapure water from an ultrapure water main pipe and air from a purified oxygen-enriched air main pipe are vaporized by the vaporizer 6-1 at the same time, then are sent to the powder making reactor 6-2, and are subjected to catalytic oxidation reaction with high-purity vanadium oxychloride from the high-purity vanadium oxychloride storage tank 5-5, so that high-purity vanadium pentoxide powder and chlorine-enriched flue gas are generated; the reaction temperature in the catalytic oxidation process is 120-620 ℃; conveying the chlorine-rich flue gas to a chlorine circulating system; sending the generated high-purity vanadium pentoxide to the high-purity vanadium bunker 6-6 for storage;

after the high-temperature chlorination residue in the waste heat recovery fluidized bed 7-1 is cooled in a nitrogen fluidized manner, the high-temperature chlorination residue is sent to the residue washing stirring kettle 8-1 for water washing and dechlorination treatment; the waste heat recovery fluidized bed heat exchanger 7-2 recovers sensible heat of the chlorination residues from the waste heat recovery fluidized bed 7-1, and provides heat for the evaporative crystallizer 8-4 through the crystallization heat exchanger 8-5, so that waste heat utilization is realized, energy is saved, and consumption is reduced; conveying the chlorinated residue washing slurry from the residue washing stirring kettle 8-1 to the residue slurry settling tank 8-1 for settling treatment; the settled slurry is treated by the residue washing filter 8-3; the chlorine content of the filter tailings is within 2.0 percent, and the filter residues are sent to iron making; the supernatant from the residue slurry settling tank 8-2 and the washing water from the residue washing filter 8-3 are sent to the evaporative crystallizer 8-4 for evaporative crystallization; the produced distilled water is condensed by the evaporation water condenser 8-6 and then is sent to a process water header pipe; washing the obtained chlorine salt by the crystallized salt washing filter 8-7 to obtain a chlorine salt product; and returning the generated washing water to the residue washing stirring kettle 8-1 for recycling.

Preferably, the method comprises the following steps: the vanadium resource in the vanadium resource bin 1-1 comprises one or more of vanadium slag, vanadium titano-magnetite and denitration catalyst; the carbon source in the carbon source bin 2-3 is one or more of activated carbon, metallurgical coke, petroleum coke and coal powder.

Preferably, the method comprises the following steps: in the chlorination furnace 3-1, the operating gas speed is 0.04-4.00 m/s, and the mole fraction of chlorine in the chlorine-nitrogen mixed gas entering the air chamber is 15-100%.

Preferably, the method comprises the following steps: in the powder preparation reactor 6-2, the mass of the introduced water vapor is 0.05-12% of that of the introduced vanadium oxychloride, the volume fraction of the oxygen content in the introduced clean oxygen-enriched air is 29-97%, and the purity of the high-purity vanadium pentoxide is more than 99.5%.

According to the invention, vanadium resources enter a chlorination furnace for selective chlorination through pretreatment processes of granulation, oxidation, crushing, screening and the like, vanadium in the vanadium resources is converted into gaseous vanadium oxychloride, most impurities such as iron, chromium, calcium, phosphorus, manganese, titanium, silicon and the like in the vanadium resources are left in chlorination residues, and effective separation of vanadium and other impurities is realized. The high-purity vanadium pentoxide is prepared by sequentially carrying out the procedures of dust removal, leaching, sedimentation, rectification, purification, catalytic oxidation and the like on gaseous vanadium oxychloride. And (3) sequentially carrying out the processes of waste heat recovery, washing dechlorination, settling separation, filtering washing and the like on the chlorination residues to obtain filter residues and washing liquid, returning the filter residues to ironmaking, and evaporating and crystallizing the washing liquid to obtain chlorine salt.

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

(1) vanadium resources are subjected to oxidizing roasting treatment and ore phase reforming, so that the chlorination selectivity of vanadium is greatly improved, and effective separation from other impurities is realized;

(2) the vanadium resource is screened to ensure that the particle size of the main body is between 100 and 200 meshes, thereby greatly improving the fluidization quality and realizing high-efficiency chlorination;

(3) the vanadium resource and the carbon source are fully mixed in a fluidized bed mixer according to a preset proportion, and then enter a chlorination furnace for reaction, so that the consistency of the proportion of reaction raw materials and the uniformity of mixing are ensured, and efficient and stable chlorination is realized;

(4) the carbon-adding chlorination of vanadium resources is a strong exothermic reaction, and the chlorination furnace heat exchanger arranged in the invention can remove redundant heat to prevent the chlorination furnace from being overheated;

(5) the heat exchanger of the dust collection tower is used for recovering part of sensible heat of the high-temperature chlorination flue gas and providing heat for the reboiler and the powder preparation reactor, so that energy conservation and consumption reduction are realized, and the production cost is reduced;

(6) the waste heat recovery fluidized bed heat exchanger is used for recovering sensible heat of the high-temperature chlorination residues and providing heat for the evaporation crystallizer, so that energy conservation and consumption reduction are realized, and the production cost is reduced;

(7) in the invention, chlorination residues are washed with water for dechlorination, and the treated tailings can be returned to ironmaking for use, so that the comprehensive utilization of the tailings is realized;

(8) according to the invention, the catalytic oxidation of the vanadium oxychloride is realized by adding a small amount of water to the oxygen-enriched air, so that high-purity vanadium pentoxide and chlorine-enriched tail gas are obtained, the chlorine gas is recycled, and the production and environmental protection costs are greatly reduced.

The vanadium pentoxide prepared by the vanadium resource chlorination method can effectively improve chlorination selectivity, realize high-efficiency separation from other impurities, realize comprehensive treatment of chlorination slag and effective circulation of chlorine, realize sensible heat recycling of high-temperature chlorination flue gas and high-temperature chlorination residues, have the advantages of high efficiency, low energy consumption, no pollution, good product quality and the like, and can effectively improve economic benefits and social benefits of the technology for preparing the vanadium pentoxide by the vanadium resource chlorination method.

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 producing vanadium pentoxide by clean chlorination of vanadium resources.

Reference numerals:

1, a material preparation section;

1-1 vanadium resource storage bin 1-2 vanadium resource screw feeder 1-3 disc granulator

1-4 oxidizing roasting rotary kiln 1-5 double-roller machine 1-6 coarse grain sieving machine

1-7 fine particle screening machines;

2, a material mixing section;

2-1 screening vanadium resource bin 2-2 screening vanadium resource feeder 2-3 carbon source bin

2-4 carbon source feeder 2-5 fluidized bed mixer;

3, a chlorination dust collection section;

3-1 chlorination furnace, 3-2 chlorination furnace heat exchanger and 3-3 dust collection tower

3-4 dust collecting tower heat exchanger;

4 leaching and settling section;

4-1 elution tower 4-2 slurry pump 4-3 elution tower heat exchanger

4-4 drip catcher 4-5 drip washing slurry settling tank;

5, a refining section;

5-1 rectifying tower 5-2 reboiler 5-3 reboiler heat exchanger

5-4 high-purity vanadium oxytrichloride condenser 5-5 high-purity vanadium oxytrichloride storage tank;

6, a powder making section;

6-1 vaporizer 6-2 powder process reactor 6-3 powder process heat exchanger

6-4 powder process soft water storage tank 6-5 powder process soft water circulating pump 6-6 high-purity vanadium feed bin

6-7 of a high-purity vanadium screw feeder;

7, a waste heat utilization section;

7-1 waste heat recovery fluidized bed 7-2 waste heat recovery fluidized bed heat exchanger 7-3 waste heat recovery soft water storage tank

7-4 waste heat recovery circulating pump;

8, a residue treatment section;

8-1 residue washing stirring kettle 8-2 residue slurry settling tank 8-3 residue washing filter

8-4 evaporative crystallizer 8-5 crystallization heat exchanger 8-6 evaporative water condenser

8-7 washing the filter with crystallized salt.

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 producing high-purity vanadium pentoxide by clean chlorination of vanadium resources.

Example 1

With reference to fig. 1, the system for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources used in this embodiment includes a material preparation section 1, a material mixing section 2, a chlorination dust collecting section 3, a leaching and settling section 4, a refining section 5, a powder making section 6, a waste heat utilization section 7, and a residue treatment section 8;

a discharge hole at the bottom of the vanadium resource bin 1-1 is connected with a feed inlet of the vanadium resource screw feeder 1-2; the discharge port of the vanadium resource screw feeder 1-2 is connected with the feed port of the disc granulator 1-3 through a pipeline; the feed back port of the disc granulator 1-3 is connected with the fine powder outlet of the fine particle sieving machine 1-7 through a pipeline; the discharge hole of the disc granulator 1-3 is connected with the feed hole of the oxidizing roasting rotary kiln 1-4 through a pipeline; an air inlet is arranged at the upper part of the oxidizing roasting rotary kiln 1-4; the discharge hole of the oxidizing roasting rotary kiln 1-4 is connected with the feed inlet of the double-roller machine 1-5; the feed inlets of the double-roller machines 1-5 are simultaneously connected with the coarse grain outlets of the coarse grain sieving machines 1-6 through pipelines; the discharge port of the double-roller machine 1-5 is connected with the feed port of the coarse grain sieving machine 1-6 through a pipeline; a fine grain outlet of the coarse grain sieving machine 1-6 is connected with a feed inlet of the fine grain sieving machine 1-7 through a pipeline; a fine grain outlet of the fine grain sieving machine 1-7 is connected with a feed inlet of a vanadium sieving resource bin 2-1 through a pipeline;

a discharge hole of the screening vanadium resource bin 2-1 is connected with a feed hole of the screening vanadium resource feeder 2-2; a discharge hole of the carbon source bin 2-3 is connected with a feed hole of the carbon source feeder 2-4; the discharge hole of the screening vanadium resource feeder 2-2 and the discharge hole of the carbon source feeder 2-4 are connected with the feed inlet of the fluidized bed mixer 2-5 through pipelines; a loosening air inlet of the fluidized bed mixer 2-5 is connected with a nitrogen header pipe through a pipeline; the discharge hole of the fluidized bed mixer 2-5 is connected with the feed inlet of the chlorination furnace 3-1 through a pipeline;

the air inlet of the chlorination furnace 3-1 is respectively connected with a chlorine gas main pipe, a circulating chlorine gas main pipe and a nitrogen gas main pipe; the middle upper part of the chlorination furnace 3-2 is provided with a chlorination furnace heat exchanger 3-2; a slurry inlet at the top of the chlorination furnace 3-2 is connected with a kettle bottom liquid outlet of the reboiler 5-2 through a pipeline; a flue gas outlet of the chlorination furnace 3-2 is connected with a flue gas inlet of the dust collecting tower 3-3 through a pipeline; a slag discharge port of the chlorination furnace 3-1 is connected with a feed port of the preheating recovery fluidized bed 7-1 through a pipeline; a slurry inlet at the top of the dust collecting tower 3-3 is connected with a kettle bottom liquid outlet of the reboiler 5-2 through a pipeline; a slag discharge port of the dust collection tower 3-3 is connected with a feed port of the preheating recovery fluidized bed 7-1 through a pipeline; the gas outlet of the dust collecting tower 3-3 is connected with the gas inlet of the leaching tower 4-1 through a pipeline; a dust collecting tower heat exchanger 3-4 is arranged in the middle of the dust collecting tower 3-3; a heat flow outlet of the dust collection tower heat exchanger 3-4 is connected with a heat flow inlet of the reboiler 5-3 through a pipeline; the heat flow inlet of the dust collection tower heat exchanger 3-4 is connected with the heat flow outlet of the powder-making soft water circulating pump 6-5 through a pipeline;

the bottom of the leaching tower 4-1 is provided with a slurry pump 4-2; the top of the leaching tower 4-1 is provided with a leaching tower heat exchanger 4-3; a gas outlet of the leaching tower 4-1 is connected with a gas inlet of the drip catcher 4-4 through a pipeline; the tail gas outlet of the drip catcher 4-4 is connected with the gas inlet of the environmental workshop through a pipeline; the bottom liquid outlet of the leaching tower 4-1 and the bottom liquid outlet of the drip catcher 4-4 are both connected with the feed inlet of the leaching slurry settling tank 4-5 through pipelines; a slurry outlet of the leaching slurry settling tank 4-5 is connected with a slurry inlet at the top of the chlorination furnace 3-1 and the dust collecting tower 3-3 through pipelines; the supernatant outlet of the leaching slurry settling tank 4-5 is connected with the liquid inlet of the rectifying tower 5-1 through a pipeline;

a gas inlet of the rectifying tower 5-1 is connected with a gas outlet of the reboiler 5-2 through a pipeline; the tower bottom liquid outlet of the rectifying tower 5-1 is connected with the reflux port of the reboiler 5-2 through a pipeline; a heat flow outlet of the reboiler heat exchanger 5-3 is connected with a heat flow inlet of the powder making heat exchanger 6-3 through a pipeline; a high-purity vanadium oxychloride gas outlet of the rectifying tower 5-1 is connected with a gas inlet of a high-purity vanadium oxychloride condenser 5-4 through a pipeline; the liquid outlet of the high-purity vanadium trichloride condenser 5-4 is connected with the liquid inlet of the high-purity vanadium trichloride storage tank 5-5 through a pipeline; a liquid outlet of the high-purity vanadium oxytrichloride storage tank 5-5 is connected with a feed inlet of the powder preparation reactor 6-2 through a pipeline;

the air inlet of the vaporizer 6-1 is respectively connected with the purified oxygen-enriched air main pipe and the ultrapure water main pipe through pipelines; the air outlet of the vaporizer 6-1 is connected with the air inlet of the pulverizing reactor 6-2 through a pipeline; the reaction tail gas outlet of the powder preparation reactor 6-2 is connected with the gas inlet of the chlorine circulating system through a pipeline; the pulverizing heat exchanger 6-3 is positioned in the middle of the pulverizing reactor 6-2; the heat flow outlet of the powder-making heat exchanger 6-3 is connected with the inlet of the powder-making soft water storage tank 6-4 through a pipeline; the water outlet of the powder making soft water storage tank 6-4 is connected with the water inlet of the powder making soft water circulating pump 6-5 through a pipeline; the discharge hole of the powder preparation reactor 6-2 is connected with the feed hole of the high-purity vanadium bunker 6-6 through a pipeline; a discharge hole of the high-purity vanadium bunker 6-6 is connected with a feed hole of the high-purity vanadium screw feeder 6-7;

the bottom air inlet of the waste heat recovery fluidized bed 7-1 is connected with a nitrogen header pipe; the top of the waste heat recovery fluidized bed 7-1 is provided with a tail gas outlet; a slag discharge port of the waste heat recovery fluidized bed 7-1 is connected with a feed inlet of a residue washing stirring kettle 8-1 through a pipeline; the middle part of the waste heat recovery fluidized bed 7-1 is provided with a waste heat recovery fluidized bed heat exchanger 7-2; a heat flow outlet of the waste heat recovery fluidized bed heat exchanger 7-2 is connected with a heat flow inlet of the crystallization heat exchanger 8-5 through a pipeline; the heat flow outlet of the crystallization heat exchanger 8-5 is connected with the heat flow inlet of the waste heat recovery soft water storage tank 7-3 through a pipeline; the heat flow outlet of the waste heat recovery soft water storage tank 7-3 is connected with the inlet of the waste heat recovery circulating pump 7-4 through a pipeline; a heat flow outlet of the waste heat recovery circulating pump 7-4 is connected with a heat flow inlet of the waste heat recovery fluidized bed heat exchanger 7-2 through a pipeline;

a water inlet of the residue washing stirring kettle 8-1 is connected with a process water main pipe; a water inlet of the residue washing stirring kettle 8-1 is simultaneously connected with a washing water outlet of the crystallized salt washing filter 8-7 through a pipeline; the slurry outlet of the residue washing and stirring kettle 8-1 is connected with the feed inlet of the residue slurry settling tank 8-2 through a pipeline; the supernatant outlet of the residue slurry settling tank 8-2 is connected with the liquid inlet of the evaporative crystallizer 8-4 through a pipeline; the slurry outlet of the residue slurry settling tank 8-2 is connected with the slurry inlet of the residue washing filter 8-3 through a pipeline; a washing water inlet of the residue washing filter 8-3 is connected with a process water main pipe; the residue washing filter 8-3 is provided with a residue discharge port; a washing liquid outlet of the residue washing filter 8-3 is connected with a liquid inlet of the evaporative crystallizer 8-4 through a pipeline; a water vapor outlet of the evaporative crystallizer 8-4 is connected with a gas inlet of the evaporative water condenser 8-6 through a pipeline; the liquid outlet of the evaporation water condenser 8-6 is connected with a process water header pipe; a crystallization heat exchanger 8-5 is arranged in the middle of the evaporation crystallizer 8-4; a crystallized salt outlet of the evaporation crystallizer 8-4 is connected with a crystallized salt inlet of a crystallized salt washing filter 8-7 through a pipeline; the washing water inlet of the crystallized salt washing filter 8-7 is connected with the process water main pipe through a pipeline; the crystallized salt washing filter 8-7 is provided with a chlorine salt product outlet; the washing liquid outlet of the crystallized salt washing filter 8-7 is connected with the liquid inlet of the residue washing stirring kettle 8-1 through a pipeline.

Example 2

By adopting the system described in embodiment 1, this embodiment provides a method for producing high-purity vanadium pentoxide, which includes the following steps:

vanadium resources in the vanadium resource bin 1-1 enter a disc granulator 1-3 for granulation treatment through a vanadium resource screw feeder 1-2; the granulated vanadium resource enters a vanadium resource screening bin 2-1 after being sequentially subjected to oxidizing roasting rotary kiln 1-4 ore phase reforming, roller crusher 1-5 crushing, coarse grain screening machine 1-6 and fine grain screening machine 1-7 screening; the operating temperature of the oxidizing roasting rotary kiln 1-4 is 400-1000 ℃; the vanadium resource in the screened vanadium resource bin 2-1 and the carbon source in the carbon source bin 2-3 simultaneously enter the fluidized bed mixer 2-5 through the screened vanadium resource feeder 2-2 and the carbon source feeder 2-4 respectively; after mixing, the mixture enters a chlorination furnace 3-1; the carbon content is 5-25% of the mass of the screened vanadium resource;

chlorine from the chlorine main pipe, nitrogen from the nitrogen main pipe and chlorine from the circulating chlorine main pipe enter through an air inlet at the bottom of the chlorination furnace 3-1; maintaining the vanadium resource powder and the carbon source in fluidization and carrying out chemical reaction; enabling vanadium and partial impurities in the vanadium resource to be chlorinated to form smoke rich in vanadium oxychloride and chlorination residues; the chlorination operation temperature is 280-950 ℃; the carbon-adding chlorination of vanadium resources is a strong heat release process, and in order to prevent the temperature from being too high, a chlorination furnace heat exchanger 3-2 is arranged in the middle of a chlorination furnace 3-1 and used for removing redundant heat; simultaneously, kettle bottom liquid from the reboiler 5-2 is sprayed from the top of the chlorination furnace 3-1 to assist the heat exchange of the chlorination furnace and prevent overhigh temperature; the chlorination residue is sent to a waste heat recovery fluidized bed 7-1; sending the smoke rich in vanadium oxychloride into a dust collecting tower 3-3 for dust removal treatment; spraying the slurry from the leaching slurry settling tank 4-5 from an inlet at the top of the dust collecting tower 3-3, and removing solid dust in the slurry while cooling the vanadium oxychloride flue gas; sending the dust in the dust collection tower 3-3 to a waste heat recovery fluidized bed 7-1 for treatment; the dust collecting tower heat exchanger 3-4 is used for recycling sensible heat of high-temperature flue gas in the dust collecting tower 3-3, and provides heat for the reboiler 5-2 and the powder making reactor 6-2 through the reboiler heat exchanger 5-3 and the powder making heat exchanger 6-3 respectively, so that energy conservation and consumption reduction are realized;

sending the vanadium oxychloride gas subjected to dust removal by the dust collecting tower 3-3 to a leaching tower 4-1 for leaching, and sending leached tail gas to an environment-friendly workshop for treatment after recovering liquid drops by a drop catcher 4-4; sending the vanadium oxychloride slurry in the leaching tower 4-1 and the vanadium oxychloride liquid recovered by the drip catcher 4-4 to a leaching slurry settling tower 4-5 for treatment; sending the supernatant of the leached slurry settling tank 4-5 to a rectifying tower 5-1 for rectification and purification to obtain high-purity vanadium oxychloride steam, condensing by a high-purity vanadium oxychloride condenser 5-4, and sending to a high-purity vanadium oxychloride storage tank 5-5 for storage; ultrapure water from an ultrapure water main pipe and air from a purified oxygen-enriched air main pipe are vaporized by a vaporizer 6-1 at the same time, then are sent to a powder reactor 6-2, and are subjected to catalytic oxidation reaction with high-purity vanadium oxychloride from a high-purity vanadium oxychloride storage tank 5-5, so that high-purity vanadium pentoxide powder and chlorine-enriched flue gas are generated; the reaction temperature in the catalytic oxidation process is 120-620 ℃; conveying the chlorine-rich flue gas to a chlorine circulating system; sending the generated high-purity vanadium pentoxide to a high-purity vanadium bunker 6-6 for storage;

carrying out nitrogen fluidization cooling on the high-temperature chlorination residue in the waste heat recovery fluidized bed 7-1, and then sending the cooled high-temperature chlorination residue to a residue washing stirring kettle 8-1 for washing and dechlorinating; the waste heat recovery fluidized bed heat exchanger 7-2 recovers sensible heat of the chlorination residue from the waste heat recovery fluidized bed 7-1 and provides heat for the evaporative crystallizer 8-4 through the crystallization heat exchanger 8-5, so that waste heat utilization is realized, energy is saved, and consumption is reduced; sending the chloridized residue washing slurry from the residue washing stirring kettle 8-1 to a residue slurry settling tank 8-1 for settling treatment; treating the settled slurry by a residue washing filter 8-3; the chlorine content of the filter tailings is within 2.0 percent, and the filter residues are sent to iron making; the supernatant from the residue slurry settling tank 8-2 and the washing water from the residue washing filter 8-3 are sent to an evaporative crystallizer 8-4 for evaporative crystallization; the produced distilled water is condensed by an evaporation water condenser 8-6 and then is sent to a process water main pipe; washing the obtained chlorine salt by a crystallized salt washing filter 8-7 to obtain a chlorine salt product; the generated washing water returns to the residue washing stirring kettle 8-1 for recycling.

Example 3

In the embodiment, vanadium slag is used as a raw material, the treatment capacity is 200kg/h, a high-purity vanadium pentoxide product is prepared through the working procedures of material preparation, material mixing, chlorination dust collection, leaching sedimentation, refining, powder preparation and the like, and industrial waste energy utilization and residue dechlorination treatment are realized through waste heat utilization and residue treatment.

In the oxidizing roasting rotary kiln 1-4, the oxidizing roasting temperature is 400 ℃; in the fluidized bed mixer 2-5, the addition amount of the active carbon is 25% of the mass of the screened vanadium slag; the chlorination temperature of the chlorination furnace is 950 ℃, the operation gas velocity of the chlorination furnace is 4.00m/s, and pure chlorine gas is used as a chlorination medium; in a powder preparation reactor, the mass of water vapor introduced in the catalytic oxidation process is 0.05 percent of that of vanadium oxychloride, the reaction temperature is 120 ℃, the mass fraction of oxygen in the introduced oxygen-enriched air is 29 percent, the direct yield of vanadium is 94 percent, and the purity of a high-purity vanadium pentoxide product is 99.995wt percent (4N 5); in the residue treatment section, the chlorine content of the filter residue is 0.5%.

Example 4

In the embodiment, vanadium-titanium magnetite is used as a raw material, the treatment capacity is 3 tons/h, a high-purity vanadium pentoxide product is prepared through the working procedures of material preparation, material mixing, chlorination dust collection, leaching sedimentation, refining, powder preparation and the like, and industrial waste energy utilization and residue dechlorination treatment are realized through waste heat utilization and residue treatment.

In the oxidizing roasting rotary kiln 1-4, the oxidizing roasting temperature is 1000 ℃; in the fluidized bed mixer 2-5, the addition amount of the metallurgical coke is 5% of the mass of the screened vanadium titano-magnetite; the chlorination temperature of the chlorination furnace is 280 ℃, the operation gas speed of the chlorination furnace is 0.04m/s, and the mole fraction of chlorine in the chlorine-nitrogen mixed gas entering the air chamber is 15%; in the powder preparation reactor, the mass of water vapor introduced in the catalytic oxidation process is 12 percent of that of vanadium oxychloride, the reaction temperature is 620 ℃, the mass fraction of oxygen in the introduced oxygen-enriched air is 97 percent, the direct yield of vanadium is 93 percent, and the purity of a high-purity vanadium pentoxide product is 99.5 percent (2N 5); in the residue treatment section, the chlorine content of the filter residue is 0.3%.

Example 5

In the embodiment, a denitration catalyst is used as a raw material, the treatment capacity is 600kg/h, a high-purity vanadium pentoxide product is prepared through the working procedures of material preparation, material mixing, chlorination dust collection, leaching sedimentation, refining, powder preparation and the like, and industrial waste energy utilization and residue dechlorination treatment are realized through waste heat utilization and residue treatment.

In the oxidizing roasting rotary kiln 1-4, the oxidizing roasting temperature is 800 ℃; in the fluidized bed mixer 2-5, the adding amount of petroleum coke is 20% of the mass of the screened denitration catalyst; the chlorination temperature of the chlorination furnace is 650 ℃, the operation gas speed of the chlorination furnace is 2.00m/s, and the mole fraction of chlorine in the chlorine-nitrogen mixed gas entering the air chamber is 50 percent; in the powder preparation reactor, the mass of steam introduced in the catalytic oxidation process is 5 percent of that of vanadium oxychloride, the reaction temperature is 400 ℃, the mass fraction of oxygen in the introduced oxygen-enriched air is 50 percent, the direct yield of vanadium reaches 94 percent, and the purity of a high-purity vanadium pentoxide product reaches 99.9995 percent (5N 5); in the residue treatment section, the chlorine content of the filter residue is 2.0%.

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 producing high-purity vanadium pentoxide by clean chlorination of vanadium resources is characterized by comprising a material preparation working section (1), a material mixing working section (2), a chlorination dust collection working section (3), a leaching and settling working section (4), a refining working section (5), a powder making working section (6), a waste heat utilization working section (7) and a residue treatment working section (8);

the material preparation working section (1) comprises a vanadium resource bin (1-1), a vanadium resource screw feeder (1-2), a disc granulator (1-3), an oxidizing roasting rotary kiln (1-4), a pair roller machine (1-5), a coarse grain screening machine (1-6) and a fine grain screening machine (1-7);

the material mixing working section (2) comprises a screening vanadium resource bin (2-1), a screening vanadium resource feeder (2-2), a carbon source bin (2-3), a carbon source feeder (2-4) and a fluidized bed mixer (2-5);

the chlorination dust collection workshop section (3) comprises a chlorination furnace (3-1), a chlorination furnace heat exchanger (3-2), a dust collection tower (3-3) and a dust collection tower heat exchanger (3-4);

the leaching and settling section (4) comprises a leaching tower (4-1), a slurry pump (4-2), a leaching tower heat exchanger (4-3), a drip catcher (4-4) and a leaching slurry settling tank (4-5);

the refining section (5) comprises a rectifying tower (5-1), a reboiler (5-2), a reboiler heat exchanger (5-3), a high-purity vanadium oxychloride condenser (5-4) and a high-purity vanadium oxychloride storage tank (5-5);

the powder preparation working section (6) comprises a vaporizer (6-1), a powder preparation reactor (6-2), a powder preparation heat exchanger (6-3), a powder preparation soft water storage tank (6-4), a powder preparation soft water circulating pump (6-5), a high-purity vanadium pentoxide bin (6-6) and a high-purity vanadium pentoxide screw feeder (6-7);

the waste heat utilization section (7) comprises a waste heat recovery fluidized bed (7-1), a waste heat recovery fluidized bed heat exchanger (7-2), a waste heat recovery soft water storage tank (7-3) and a waste heat recovery circulating pump (7-4);

the residue treatment section (8) comprises a residue washing stirring kettle (8-1), a residue slurry settling tank (8-2), a residue washing filter (8-3), an evaporation crystallizer (8-4), a crystallization heat exchanger (8-5), an evaporation water condenser (8-6) and a crystallized salt washing filter (8-7);

a discharge hole at the bottom of the vanadium resource bin (1-1) is connected with a feed inlet of the vanadium resource screw feeder (1-2); the discharge hole of the vanadium resource screw feeder (1-2) is connected with the feed inlet of the disc granulator (1-3) through a pipeline; a feed back port of the disc granulator (1-3) is connected with a fine powder outlet of the fine particle sieving machine (1-7) through a pipeline; the discharge hole of the disc granulator (1-3) is connected with the feed hole of the oxidizing roasting rotary kiln (1-4) through a pipeline; an air inlet is formed in the upper part of the oxidizing roasting rotary kiln (1-4); the discharge hole of the oxidizing roasting rotary kiln (1-4) is connected with the feed inlet of the double-roller machine (1-5); the feed inlet of the double-roller machine (1-5) is connected with the coarse grain outlet of the coarse grain sieving machine (1-6) through a pipeline; the discharge hole of the double-roller machine (1-5) is connected with the feed hole of the coarse grain sieving machine (1-6) through a pipeline; a fine particle outlet of the coarse particle sieving machine (1-6) is connected with a feed inlet of the fine particle sieving machine (1-7) through a pipeline; a fine grain outlet of the fine grain sieving machine (1-7) is connected with a feeding hole of the vanadium sieving resource bin (2-1) through a pipeline;

the discharge hole of the screening vanadium resource bin (2-1) is connected with the feed inlet of the screening vanadium resource feeder (2-2); a discharge hole of the carbon source bin (2-3) is connected with a feed hole of the carbon source feeder (2-4); the discharge hole of the screening vanadium resource feeder (2-2) and the discharge hole of the carbon source feeder (2-4) are connected with the feed inlet of the fluidized bed mixer (2-5) through pipelines; the loosening air inlet of the fluidized bed mixer (2-5) is connected with a nitrogen header pipe through a pipeline; the discharge hole of the fluidized bed mixer (2-5) is connected with the feed inlet of the chlorination furnace (3-1) through a pipeline;

the air inlet of the chlorination furnace (3-1) is respectively connected with a chlorine gas main pipe, a circulating chlorine gas main pipe and a nitrogen gas main pipe; the middle upper part of the chlorination furnace (3-1) is provided with the chlorination furnace heat exchanger (3-2); a slurry inlet at the top of the chlorination furnace (3-1) is connected with a kettle bottom liquid outlet of the reboiler (5-2) through a pipeline; a flue gas outlet of the chlorination furnace (3-1) is connected with a flue gas inlet of the dust collection tower (3-3) through a pipeline; the slag discharge port of the chlorination furnace (3-1) is connected with the feed inlet of the waste heat recovery fluidized bed (7-1) through a pipeline; a slurry inlet at the top of the dust collection tower (3-3) is connected with a kettle bottom liquid outlet of the reboiler (5-2) through a pipeline; the slag discharge port of the dust collection tower (3-3) is connected with the feed port of the waste heat recovery fluidized bed (7-1) through a pipeline; the gas outlet of the dust collecting tower (3-3) is connected with the gas inlet of the leaching tower (4-1) through a pipeline; a dust collection tower heat exchanger (3-4) is arranged in the middle of the dust collection tower (3-3); the heat flow outlet of the dust collection tower heat exchanger (3-4) is connected with the heat flow inlet of the reboiler (5-3) through a pipeline; the heat flow inlet of the dust collection tower heat exchanger (3-4) is connected with the heat flow outlet of the powder-making soft water circulating pump (6-5) through a pipeline;

the bottom of the leaching tower (4-1) is provided with the slurry pump (4-2); the top of the leaching tower (4-1) is provided with the leaching tower heat exchanger (4-3); the gas outlet of the leaching tower (4-1) is connected with the gas inlet of the drip catcher (4-4) through a pipeline; the tail gas outlet of the drip catcher (4-4) is connected with the gas inlet of the environment-friendly workshop through a pipeline; the bottom liquid outlet of the leaching tower (4-1) and the bottom liquid outlet of the drip catcher (4-4) are connected with the feed inlet of the leaching slurry settling tank (4-5) through pipelines; a slurry outlet of the leaching slurry settling tank (4-5) is connected with slurry inlets at the tops of the chlorination furnace (3-1) and the dust collection tower (3-3) through pipelines; the supernatant outlet of the leaching slurry settling tank (4-5) is connected with the liquid inlet of the rectifying tower (5-1) through a pipeline;

the gas inlet of the rectifying tower (5-1) is connected with the gas outlet of the reboiler (5-2) through a pipeline; a kettle bottom liquid outlet of the rectifying tower (5-1) is connected with a reflux port of the reboiler (5-2) through a pipeline; the heat flow outlet of the reboiler heat exchanger (5-3) is connected with the heat flow inlet of the pulverizing heat exchanger (6-3) through a pipeline; a high-purity vanadium oxychloride gas outlet of the rectifying tower (5-1) is connected with a gas inlet of the high-purity vanadium oxychloride condenser (5-4) through a pipeline; the liquid outlet of the high-purity vanadium trichloride condenser (5-4) is connected with the liquid inlet of the high-purity vanadium trichloride storage tank (5-5) through a pipeline; the liquid outlet of the high-purity vanadium oxytrichloride storage tank (5-5) is connected with the feed inlet of the powder preparation reactor (6-2) through a pipeline;

the air inlet of the vaporizer (6-1) is respectively connected with the oxygen-enriched air purifying main pipe and the ultrapure water main pipe through pipelines; the gas outlet of the vaporizer (6-1) is connected with the gas inlet of the pulverizing reactor (6-2) through a pipeline; the reaction tail gas outlet of the powder preparation reactor (6-2) is connected with the gas inlet of the chlorine circulating system through a pipeline; the powder making heat exchanger (6-3) is positioned in the middle of the powder making reactor (6-2); the heat flow outlet of the powder-making heat exchanger (6-3) is connected with the inlet of the powder-making soft water storage tank (6-4) through a pipeline; the water outlet of the powder making soft water storage tank (6-4) is connected with the water inlet of the powder making soft water circulating pump (6-5) through a pipeline; the discharge hole of the powder preparation reactor (6-2) is connected with the feed inlet of the high-purity vanadium pentoxide bin (6-6) through a pipeline; the discharge hole of the high-purity vanadium pentoxide bin (6-6) is connected with the feed hole of the high-purity vanadium pentoxide screw feeder (6-7);

the bottom air inlet of the waste heat recovery fluidized bed (7-1) is connected with a nitrogen header pipe; a tail gas outlet is arranged at the top of the waste heat recovery fluidized bed (7-1); a slag discharge port of the waste heat recovery fluidized bed (7-1) is connected with a feed inlet of the residue washing stirring kettle (8-1) through a pipeline; the middle part of the waste heat recovery fluidized bed (7-1) is provided with the waste heat recovery fluidized bed heat exchanger (7-2); the heat flow outlet of the waste heat recovery fluidized bed heat exchanger (7-2) is connected with the heat flow inlet of the crystallization heat exchanger (8-5) through a pipeline; the heat flow outlet of the crystallization heat exchanger (8-5) is connected with the heat flow inlet of the waste heat recovery soft water storage tank (7-3) through a pipeline; the heat flow outlet of the waste heat recovery soft water storage tank (7-3) is connected with the inlet of the waste heat recovery circulating pump (7-4) through a pipeline; a heat flow outlet of the waste heat recovery circulating pump (7-4) is connected with a heat flow inlet of the waste heat recovery fluidized bed heat exchanger (7-2) through a pipeline;

a water inlet of the residue washing stirring kettle (8-1) is connected with a process water main pipe; the water inlet of the residue washing stirring kettle (8-1) is connected with the washing water outlet of the crystallized salt washing filter (8-7) through a pipeline; the slurry outlet of the residue washing stirring kettle (8-1) is connected with the feed inlet of the residue slurry settling tank (8-2) through a pipeline; the supernatant outlet of the residue slurry settling tank (8-2) is connected with the liquid inlet of the evaporative crystallizer (8-4) through a pipeline; the slurry outlet of the residue slurry settling tank (8-2) is connected with the slurry inlet of the residue washing filter (8-3) through a pipeline; the washing water inlet of the residue washing filter (8-3) is connected with a process water main pipe; the residue washing filter (8-3) is provided with a residue discharge port; a washing liquid outlet of the residue washing filter (8-3) is connected with a liquid inlet of the evaporative crystallizer (8-4) through a pipeline; a water vapor outlet of the evaporative crystallizer (8-4) is connected with a gas inlet of the evaporative water condenser (8-6) through a pipeline; the liquid outlet of the evaporation water condenser (8-6) is connected with a process water main pipe; the middle part of the evaporative crystallizer (8-4) is provided with the crystallization heat exchanger (8-5); a crystallized salt outlet of the evaporative crystallizer (8-4) is connected with a crystallized salt inlet of the crystallized salt washing filter (8-7) through a pipeline; the washing water inlet of the crystallized salt washing filter (8-7) is connected with the process water main pipe through a pipeline; the crystallized salt washing filter (8-7) is provided with a chlorine salt product outlet; and a washing liquid outlet of the crystallized salt washing filter (8-7) is connected with a liquid inlet of the residue washing stirring kettle (8-1) through a pipeline.

2. A method for producing high-purity vanadium pentoxide based on clean chlorination of vanadium resources by the system of claim 1, the method comprising the steps of:

the vanadium resource in the vanadium resource bin (1-1) enters the disc granulator (1-3) through the vanadium resource screw feeder (1-2) for granulation treatment; the granulated vanadium resource sequentially passes through the oxidizing roasting rotary kiln (1-4) for ore phase reforming, the double-roller machine (1-5) for crushing, the coarse grain screening machine (1-6) and the fine grain screening machine (1-7) for screening and then enters the screening vanadium resource bin (2-1); the operating temperature of the oxidizing roasting rotary kiln (1-4) is 400-1000 ℃; vanadium resources in the screening vanadium resource bin (2-1) and carbon sources in the carbon source bin (2-3) simultaneously enter the fluidized bed mixer (2-5) through the screening vanadium resource feeder (2-2) and the carbon source feeder (2-4) respectively; after mixing, the mixture enters the chlorination furnace (3-1); the carbon content is 5-25% of the mass of the screened vanadium resource;

chlorine from the chlorine main pipe, nitrogen from the nitrogen main pipe and chlorine from the circulating chlorine main pipe enter through an air inlet at the bottom of the chlorination furnace (3-1); maintaining the vanadium resource powder and the carbon source in fluidization and carrying out chemical reaction; enabling vanadium and partial impurities in the vanadium resource to be chlorinated to form smoke rich in vanadium oxychloride and chlorination residues; the chlorination operation temperature is 280-950 ℃; the carbon-matching chlorination of vanadium resources is a strong heat release process, and in order to prevent the temperature from being too high, the heat exchanger (3-2) of the chlorination furnace is arranged in the middle of the chlorination furnace (3-1) and used for removing redundant heat; simultaneously, kettle bottom liquid from the reboiler (5-2) is sprayed from the top of the chlorination furnace (3-1) to assist the heat exchange of the chlorination furnace and prevent the temperature from being overhigh; the chlorination residue is sent to the waste heat recovery fluidized bed (7-1); the smoke rich in vanadium oxychloride is sent to the dust collecting tower (3-3) for dust removal treatment; slurry from the leaching slurry settling tank (4-5) is sprayed from an inlet at the top of the dust collecting tower (3-3), and solid dust in the slurry is removed while vanadium oxychloride flue gas is cooled; the dust in the dust collection tower (3-3) is sent to the waste heat recovery fluidized bed (7-1) for treatment; the dust collection tower heat exchanger (3-4) is used for recycling sensible heat of high-temperature flue gas in the dust collection tower (3-3), and heat is provided for the reboiler (5-2) and the pulverizing reactor (6-2) through the reboiler heat exchanger (5-3) and the pulverizing heat exchanger (6-3) respectively, so that energy conservation and consumption reduction are realized;

sending the vanadium oxychloride gas subjected to dust removal by the dust collecting tower (3-3) to the leaching tower (4-1) for leaching, and sending leached tail gas to an environment-friendly workshop for treatment after recovering liquid drops by the drip catcher (4-4); sending the vanadium oxychloride slurry in the leaching tower (4-1) and the vanadium oxychloride liquid recovered by the drip catcher (4-4) to the leaching slurry settling tank (4-5) for treatment; sending the supernatant of the leaching slurry settling tank (4-5) to the rectifying tower (5-1) for rectification and purification to obtain high-purity vanadium oxychloride steam, and sending the high-purity vanadium oxychloride steam to the high-purity vanadium oxychloride storage tank (5-5) for storage after being condensed by the high-purity vanadium oxychloride condenser (5-4); ultrapure water from an ultrapure water main pipe and air from a purified oxygen-enriched air main pipe are vaporized by the vaporizer (6-1) at the same time, then are sent into the powder making reactor (6-2), and are subjected to catalytic oxidation reaction with high-purity vanadium oxychloride from the high-purity vanadium oxychloride storage tank (5-5), so that high-purity vanadium pentoxide powder and chlorine-enriched flue gas are generated; the reaction temperature in the catalytic oxidation process is 120-620 ℃; conveying the chlorine-rich flue gas to a chlorine circulating system; sending the generated high-purity vanadium pentoxide to a high-purity vanadium pentoxide storage bin (6-6) for storage;

high-temperature chlorination residues in the waste heat recovery fluidized bed (7-1) are subjected to nitrogen fluidization cooling and then are sent to the residue washing stirring kettle (8-1) for water washing and dechlorination treatment; the waste heat recovery fluidized bed heat exchanger (7-2) recovers sensible heat of the chlorination residues from the waste heat recovery fluidized bed (7-1), and provides heat for the evaporative crystallizer (8-4) through the crystallization heat exchanger (8-5), so that waste heat utilization is realized, energy is saved, and consumption is reduced; conveying the chlorinated residue washing slurry from the residue washing stirring kettle (8-1) to the residue slurry settling tank (8-2) for settling treatment; the settled slurry is treated by the residue washing filter (8-3); the chlorine content of the filtered tailings is within 2.0 percent, and the filtered slag is sent to ironmaking treatment; supernatant from the residue slurry settling tank (8-2) and washing water from the residue washing filter (8-3) are sent to the evaporative crystallizer (8-4) for evaporative crystallization; the produced distilled water is condensed by the evaporation water condenser (8-6) and then is sent to a process water header pipe; washing the obtained chlorine salt by the crystallized salt washing filter (8-7) to obtain a chlorine salt product; the generated washing water returns to the residue washing stirring kettle (8-1) for recycling.

3. The method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources as claimed in claim 2, wherein the vanadium resources in the vanadium resource bin (1-1) comprise one or more of vanadium slag, vanadium titano-magnetite and denitration catalyst;

the carbon source in the carbon source bin (2-3) is one or more of activated carbon, metallurgical coke, petroleum coke and coal powder.

4. The method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources as claimed in claim 2, wherein the operating gas velocity in the chlorination furnace (3-1) is 0.04 m/s-4.00 m/s, and the mole fraction of chlorine in the chlorine-nitrogen mixed gas entering the air chamber is 15% -100%.

5. The method for producing high-purity vanadium pentoxide by clean chlorination of vanadium resources as claimed in claim 2, wherein in the powder preparation reactor (6-2), the amount of water vapor introduced is 0.05-12% of the mass of vanadium oxychloride, the volume fraction of oxygen in the clean oxygen-enriched air is 29-97%, and the purity of high-purity vanadium pentoxide is more than 99.5%.