CN109136536B - Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate - Google Patents

Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate Download PDF

Info

Publication number
CN109136536B
CN109136536B CN201811121174.8A CN201811121174A CN109136536B CN 109136536 B CN109136536 B CN 109136536B CN 201811121174 A CN201811121174 A CN 201811121174A CN 109136536 B CN109136536 B CN 109136536B
Authority
CN
China
Prior art keywords
molten salt
chloride
low
roasting
concentrate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201811121174.8A
Other languages
Chinese (zh)
Other versions
CN109136536A (en
Inventor
李梅
张栋梁
高凯
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Inner Mongolia Jarud Banner Lu'an Mining Industry Co ltd
Original Assignee
Inner Mongolia Jarud Banner Lu'an Mining Industry Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Inner Mongolia Jarud Banner Lu'an Mining Industry Co ltd filed Critical Inner Mongolia Jarud Banner Lu'an Mining Industry Co ltd
Priority to CN201811121174.8A priority Critical patent/CN109136536B/en
Publication of CN109136536A publication Critical patent/CN109136536A/en
Application granted granted Critical
Publication of CN109136536B publication Critical patent/CN109136536B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00Preliminary treatment of ores or scrap
    • C22B1/02Roasting processes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C1/00Magnetic separation
    • B03C1/005Pretreatment specially adapted for magnetic separation
    • B03C1/015Pretreatment specially adapted for magnetic separation by chemical treatment imparting magnetic properties to the material to be separated, e.g. roasting, reduction, oxidation
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00Silicon; Compounds thereof
    • C01B33/08Compounds containing halogen
    • C01B33/107Halogenated silanes
    • C01B33/1071Tetrachloride, trichlorosilane or silicochloroform, dichlorosilane, monochlorosilane or mixtures thereof
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B34/00Obtaining refractory metals
    • C22B34/20Obtaining niobium, tantalum or vanadium
    • C22B34/24Obtaining niobium or tantalum

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

The invention discloses a reducing roasting-molten salt chlorination extraction method of low-grade niobium concentrate, which comprises the steps of reducing roasting; magnetic separation; the method has the advantages that the process flow is short, the impurity element iron influencing the chlorination reaction is separated out by adopting a reduction roasting-magnetic separation mode to obtain the iron ore concentrate, the iron grade of the iron ore concentrate is over 75 percent, and the iron ore concentrate can be used as a high-quality raw material for ferrous metallurgy; the method accords with atom economy, can realize the separation and purification of niobium through chlorination reaction and subsequent cooling separation process, can recover associated resources from chloride dust mud, and also obtains the key raw material silicon tetrachloride for the fumed silica; the method recycles the associated resources which can become three wastes originally by products with high added values, and reduces the discharge amount of the three wastes.

Description

Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate
Technical Field
The invention belongs to the technical field of metallurgy, in particular to a method for extracting low-grade niobium concentrate by reduction roasting-molten salt chlorination,
background
China is the largest niobium consuming country in the world, but concentrate products required by niobium industry almost all depend on import, the capacity of niobium concentrate in China is less than 0.1% of the global yield, but the consumption of niobium in China accounts for 26% of the world, and with the continuous development of economic society in China, the demand of niobium in China is more and more, and according to prediction, the demand growth rate of niobium in China is increased until 2035 years, the demand of niobium in China is far from balance of supply and demand, so that the niobium resources in China are highly dependent on China, the demand is far greater than the supply, and the situation of supply and demand shortage exists for a long time.
The niobium resource amount in China is large, but most of the niobium resources are complex associated ores, the niobium resources have little economic value, and the niobium resources are only in the areas of Jiangxi Yichun, Xinjiang cocoa, Guangxi chestnut and the like. The niobium ore of the concomitance type in China is taken as the raw material, and the grade obtained by ore dressing is only (Nb)2O5) 2-15% far lower than the grade (more than or equal to 50%) of the imported niobium concentrate. Although the Baiyunebo ore is the largest niobium resource area in China, the reserve reaches 660 ten thousand tons and is the second place in the world, the Baiyunebo ore is not developed and utilized to date because no economic and effective technology exists. The 801 mine has a large niobium resource reserve and is one of the mineral deposits with the highest raw ore grade in China at present, but the 801 mine cannot be developed and utilized to date due to the lack of technology, and even the whole mine is not developed.
Along with the increasing scarcity of mineral resources in China, the multi-metal associated ore becomes a mainstream resource, and the low-grade niobium concentrate needs a feasible extraction technology. The chloridizing metallurgy is an important branch of a metallurgical method, in the past, due to the reasons of technology, equipment and the like, the metallurgical industry talks about chloridizing change and is afraid of chloridizing metallurgy, but along with the continuous improvement of the technological level, the cleanness of the chloridizing metallurgy is more and more reflected, the iron content in low-grade niobium concentrate is generally higher, and the process sequence of the whole chloridizing metallurgy can be influenced by the existence of a large amount of iron.
The present invention has been made in view of the above circumstances.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate, which adopts a reduction roasting-magnetic separation mode to firstly remove impurity iron elements influencing chlorination reaction and separation, can realize separation and purification of niobium through chlorination reaction and subsequent cooling separation processes, can also recover associated resources from chloride dust mud, also obtains key raw material silicon tetrachloride for gas phase white carbon black, has good environmental benefit and reduces the discharge of three wastes.
In order to achieve the purpose, the invention adopts the following technical scheme:
a reducing roasting-molten salt chlorination extraction method of low-grade niobium concentrate comprises the following steps:
(1) reduction roasting: mixing and roasting the low-grade niobium concentrate and a reducing agent to obtain roasted ore;
(2) magnetic separation: crushing and grinding the roasted ore, then carrying out magnetic separation, and carrying out magnetic separation to obtain iron ore concentrate and nonmagnetic substances;
(3) molten salt chlorination reaction: adding solid chloride molten salt into a molten salt chlorination furnace, heating to obtain liquid chloride molten salt, adding the nonmagnetic substance and metallurgical coke or graphite into the liquid chloride molten salt, introducing chlorine into the liquid chloride molten salt to perform molten salt chlorination reaction to generate an overflow product, performing four-section cooling separation on the overflow product, and periodically discharging the hard-to-boil molten salt in the molten salt chlorination furnace to keep the molten salt liquid level in the molten salt chlorination furnace stable.
Further, the low-grade niobium concentrate is a concentrate containing 2-15% of Nb2O5 by mass and 15-50% of iron by mass.
Further, in the step (1), the reducing agent is one or more of coke, coal powder and petroleum coke, and the mass ratio of the low-grade niobium concentrate to the reducing agent is 1: 0.15-0.35.
Further, the temperature of the calcination in the step (1) is 700-.
Further, the content of the particle size of the roasted ore ground in the step (2) which is smaller than 100 meshes is more than or equal to 50 percent.
Further, the magnetic field intensity of the magnetic separation in the step (2) is 0.15-0.6T.
Further, the solid chloride molten salt in the step (3) is one or more of alkali metal chloride, alkaline earth metal chloride and rare earth chloride.
Further, the mass ratio of the solid chloride molten salt to the nonmagnetic substance in the step (3) is 30-40:1, and the mass ratio of the nonmagnetic substance to the metallurgical coke or graphite is 1: 0.1-0.35, and the mass ratio of the chlorine gas to the nonmagnetic substance is 2-4.5: 1.
Further, the temperature of the molten salt chlorination reaction in the step (3) is 700-.
Further, in the four-stage cooling separation in the step (3), the temperature of the first-stage cooling separation is 350-450 ℃, the temperature of the second-stage cooling separation is 250-340 ℃, the temperature of the third-stage cooling separation is 60-240 ℃, and the temperature of the four-stage cooling separation is-30-50 ℃.
Further, the high-melting-point dust slag and gaseous chloride are obtained through first-stage cooling separation; cooling and separating the second stage to obtain solid ferric chloride and gaseous chloride; and the solid niobium chloride and the gaseous chloride are obtained through three-stage cooling separation, and the liquid silicon tetrachloride, the carbon dioxide and a small amount of unreacted chlorine gas mixed gas are obtained through four-stage cooling separation.
Compared with the prior art, the invention has the beneficial effects that:
(1) the reducing roasting-molten salt chlorination extraction method of the low-grade niobium concentrate has short process flow, firstly, impurity element iron influencing chlorination reaction is separated out by adopting a reducing roasting-magnetic separation mode to obtain iron concentrate, the grade of the iron concentrate is more than 75%, and the iron concentrate can be used as a high-quality raw material for ferrous metallurgy;
(2) the preparation method disclosed by the invention has good economic benefits, accords with atom economy, can realize the separation and purification of niobium through chlorination reaction and subsequent cooling separation process, can recover associated resources from chloride dust mud, and also obtains the key raw material silicon tetrachloride for the fumed silica;
(3) the preparation method has good environmental benefit, and the associated resources which can be the three wastes originally are recycled by products with high added values by adopting the preparation method, so that the discharge amount of the three wastes is reduced.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a process flow diagram of the reductive roasting-molten salt chlorination extraction method of low-grade niobium concentrate of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.
Fig. 1 is a process flow diagram of the reductive roasting-molten salt chlorination extraction method of low-grade niobium concentrate of the present invention.
Example 1
The low-grade niobium concentrate of the embodiment contains Nb in mass fraction2O52.33%, Fe 35.86% and SiO2The preparation method of 16.53 percent of inner Mongolia bayan obo ore low-grade niobium concentrate serving as a raw material comprises the following steps:
(1) reduction roasting: mixing and pelletizing low-grade niobium concentrate and coal powder, and roasting, wherein the mass ratio of the low-grade niobium concentrate to the coal powder is 1:0.35, the roasting temperature is 770 ℃, and roasting is carried out to obtain roasted ore;
(2) magnetic separation: crushing and grinding the roasted ore, wherein the content of the ground particle size is less than 100 meshes and is more than or equal to 52%, then carrying out magnetic separation, wherein the magnetic separation comprises primary roughing and primary scavenging, the strength of a roughing magnetic field is 0.3T, the strength of a scavenging magnetic field is 0.3T, the roughing concentrate and the scavenging concentrate are combined to obtain iron concentrate, scavenging is carried out on roughing tailings, the scavenging tailings are non-magnetic separation substances and serve as raw materials of a molten salt chlorination reaction, and the iron grade of the iron concentrate reaches 85.3% through determination;
(3) molten salt chlorination reaction: adding potassium chloride and sodium chloride into a molten salt chlorination furnace, heating to obtain liquid potassium chloride and sodium chloride molten salt, adding the nonmagnetic substance and metallurgical coke into the liquid potassium chloride and sodium chloride molten salt, introducing chlorine into the liquid potassium chloride and sodium chloride molten salt to perform molten salt chlorination reaction, wherein the temperature of the molten salt chlorination reaction is 700-800 ℃, and reacting to generate an overflow, wherein the mass ratio of the potassium chloride to the nonmagnetic substance to the sodium chloride is 20: 20:1, the mass ratio of metallurgical coke to nonmagnetic substances is 0.1:1, and the mass ratio of chlorine to nonmagnetic substances is 2.5: 1, carrying out four-section cooling separation on the overflow, and periodically discharging the refractory molten salt in the molten salt chlorination furnace to keep the molten salt liquid level in the molten salt chlorination furnace stable:
wherein, the four-stage cooling separation is as follows:
①, primary cooling separation, namely performing primary cooling separation on the overflow of the molten salt chlorination reaction overflowing the molten salt chlorination furnace, controlling the temperature at 360-400 ℃ to obtain high-melting-point dust slag which is unreacted low-grade niobium concentrate and gaseous chloride;
② second-stage cooling separation, which is to perform second-stage cooling separation on the gaseous chloride obtained by the first-stage cooling separation, control the temperature at 250-305 ℃ to obtain solid ferric chloride and gaseous chloride, and the purity of the ferric chloride is 92.5% by determination;
③, performing three-stage cooling separation, namely performing three-stage cooling separation on the gaseous chloride obtained by the two-stage cooling separation, controlling the temperature at 60-90 ℃ to obtain solid niobium chloride and gaseous chloride, wherein the purity of the niobium chloride is 96.5% and the recovery rate of the niobium is 83.4% through measurement;
④ and cooling and separating in four stages, namely cooling and separating the gaseous chloride obtained by cooling and separating in the three stages in four stages, controlling the temperature at minus 30-0 ℃ to obtain liquid silicon tetrachloride and mixed gas of carbon dioxide and unreacted chlorine, wherein the purity of the silicon tetrachloride is 89.9% and the silicon recovery rate is 89.0% through measurement.
Example 2
The low-grade niobium concentrate of the embodiment contains Nb in mass fraction2O56.07%, Fe 21.04% and SiO222.49 percent of inner Mongolia bayan obo ore low-grade niobium concentrate is taken as a raw material, and the preparation method comprises the following steps:
(1) reduction roasting: mixing and pelletizing low-grade niobium concentrate and coke, and then roasting, wherein the mass ratio of the low-grade niobium concentrate to the coke is 1:0.15, the roasting temperature is 950 ℃, and roasting is carried out to obtain roasted ore;
(2) magnetic separation: crushing and grinding the roasted ore, wherein the content of the ground particle size is less than 100 meshes and is more than or equal to 69%, then carrying out magnetic separation on the ground roasted ore, wherein the magnetic separation comprises primary roughing and primary scavenging, the strength of a roughing magnetic field is 0.15T, the strength of a scavenging magnetic field is 0.18T, the roughing concentrate and the scavenging concentrate are combined to obtain iron concentrate, carrying out scavenging on roughing tailings, and the scavenging tailings are non-magnetic separation substances and are used as raw materials of a molten salt chlorination reaction, and the iron grade of the iron concentrate reaches 95.6% by determination;
(3) molten salt chlorination reaction: adding sodium chloride and rare earth chloride into a molten salt chlorination furnace, heating to obtain liquid sodium chloride and rare earth chloride molten salt, adding the nonmagnetic substance, metallurgical coke and graphite into the liquid sodium chloride and rare earth chloride molten salt, introducing chlorine into the liquid sodium chloride and rare earth chloride molten salt to perform molten salt chlorination reaction, wherein the temperature of the molten salt chlorination reaction is 800-1000 ℃, and reacting to generate an overflow, wherein the mass ratio of the sodium chloride to the rare earth chloride to the nonmagnetic substance is 20: 10:1, wherein the mass ratio of metallurgical coke, graphite and nonmagnetic substances is 0.1: 0.1:1, the mass ratio of chlorine gas to nonmagnetic substances is 2.1: 1, carrying out four-section cooling separation on the overflow, and periodically discharging the refractory molten salt in the molten salt chlorination furnace to keep the molten salt liquid level in the molten salt chlorination furnace stable:
wherein, the four-stage cooling separation is as follows:
①, primary cooling separation, namely performing primary cooling separation on the overflow of the molten salt chlorination reaction overflowing the molten salt chlorination furnace, controlling the temperature at 380-430 ℃ to obtain high-melting-point dust slag which is unreacted low-grade niobium concentrate and gaseous chloride;
② second-stage cooling separation, namely performing second-stage cooling separation on the gaseous chloride obtained by the first-stage cooling separation, controlling the temperature at 270 ℃ and 310 ℃ to obtain solid ferric chloride and the gaseous chloride, wherein the purity of the ferric chloride is 93.3% by determination;
③, performing three-stage cooling separation, namely performing three-stage cooling separation on the gaseous chloride obtained by the two-stage cooling separation, controlling the temperature at 120 ℃ and 220 ℃ to obtain solid niobium chloride and the gaseous chloride, wherein the purity of the niobium chloride is 95.5% and the recovery rate of the niobium is 84.5% through determination;
④ and four-stage cooling separation, namely, carrying out four-stage cooling separation on the gaseous chloride obtained by the three-stage cooling separation, controlling the temperature to be 0-15 ℃ to obtain liquid silicon tetrachloride and mixed gas of carbon dioxide and unreacted chlorine, wherein the purity of the silicon tetrachloride is 88.4% and the silicon recovery rate is 88.3% through determination.
Example 3
The low-grade niobium concentrate of the embodiment contains Nb in mass fraction2O514.65%, Fe 8.89% and SiO225.86 percent of inner Mongolia bayan obo ore low-grade niobium concentrate is taken as a raw material, and the preparation method comprises the following steps:
(1) reduction roasting: mixing and pelletizing low-grade niobium concentrate and petroleum coke, and then roasting, wherein the mass ratio of the low-grade niobium concentrate to the petroleum coke is 1:0.15, the roasting temperature is 1150 ℃, and roasting is carried out to obtain roasted ore;
(2) magnetic separation: crushing and grinding the roasted ore, wherein the content of the ground particle size is less than 100 meshes and is not less than 60%, then carrying out magnetic separation on the ground roasted ore, wherein the magnetic separation comprises primary roughing and primary scavenging, the strength of a roughing magnetic field is 0.35T, the strength of a scavenging magnetic field is 0.38T, the roughing concentrate and the scavenging concentrate are combined to obtain iron concentrate, scavenging is carried out on roughing tailings, the scavenging tailings are non-magnetic separation substances and serve as raw materials of a molten salt chlorination reaction, and the iron grade of the iron concentrate reaches 88.6% by determination;
(3) molten salt chlorination reaction: adding potassium chloride and rare earth chloride into a molten salt chlorination furnace, heating to obtain liquid potassium chloride and rare earth chloride molten salt, adding the nonmagnetic substance and metallurgical coke into the liquid potassium chloride and rare earth chloride molten salt, introducing chlorine into the liquid potassium chloride and rare earth chloride molten salt to perform molten salt chlorination reaction, wherein the temperature of the molten salt chlorination reaction is 760-940 ℃, and reacting to generate an overflow, wherein the mass ratio of the potassium chloride to the rare earth chloride to the nonmagnetic substance is 20: 10:1, the mass ratio of metallurgical coke to nonmagnetic substances is 0.32:1, and the mass ratio of chlorine to nonmagnetic substances is 4.5:1, carrying out four-section cooling separation on the overflow, and periodically discharging the refractory molten salt in the molten salt chlorination furnace to keep the molten salt liquid level in the molten salt chlorination furnace stable:
wherein, the four-stage cooling separation is as follows:
①, primary cooling separation, namely performing primary cooling separation on the overflow of the molten salt chlorination reaction overflowing the molten salt chlorination furnace, controlling the temperature at 350-420 ℃, and obtaining high-melting-point dust slag which is unreacted low-grade niobium concentrate and gaseous chloride;
② second-stage cooling separation, namely performing second-stage cooling separation on the gaseous chloride obtained by the first-stage cooling separation, controlling the temperature at 270 ℃ and 310 ℃ to obtain solid ferric chloride and gaseous chloride, wherein the purity of the ferric chloride is 95.9% by determination;
③, performing three-stage cooling separation, namely performing three-stage cooling separation on the gaseous chloride obtained by the two-stage cooling separation, controlling the temperature at 100 ℃ and 240 ℃ to obtain solid niobium chloride and the gaseous chloride, wherein the purity of the niobium chloride is 90.5% and the recovery rate of the niobium is 84.5% through determination;
④ and four-stage cooling separation, namely, carrying out four-stage cooling separation on the gaseous chloride obtained by the three-stage cooling separation, controlling the temperature to be-15-15 ℃ to obtain liquid silicon tetrachloride and mixed gas of carbon dioxide and unreacted chlorine, wherein the purity of the silicon tetrachloride is 90.6% and the silicon recovery rate is 87.5% through measurement.
Example 4
The low-grade niobium concentrate of the embodiment contains Nb in mass fraction2O510.04%, Fe 10.98% and SiO2The preparation method of 20.88 percent of inner Mongolia Baiyunebo ore low-grade niobium concentrate serving as a raw material comprises the following steps:
(1) reduction roasting: mixing and pelletizing low-grade niobium concentrate, coke and coal powder, and then roasting, wherein the mass ratio of the low-grade niobium concentrate to the coke to the coal powder is 1: 0.1: 0.1, the roasting temperature is 1300 ℃, and roasted ore is obtained after roasting;
(2) magnetic separation: crushing and grinding the roasted ore, wherein the content of the ground particle size is more than or equal to 81 percent and less than 100 meshes, then carrying out magnetic separation on the ground roasted ore, wherein the magnetic separation comprises primary roughing and primary scavenging, the strength of a roughing magnetic field is 0.5T, the strength of a scavenging magnetic field is 0.3T, the roughing concentrate and the scavenging concentrate are combined to obtain iron concentrate, scavenging is carried out on roughing tailings, the scavenging tailings are non-magnetic separation substances and serve as raw materials of a molten salt chlorination reaction, and the iron grade of the iron concentrate reaches 90.6 percent through determination;
(3) molten salt chlorination reaction: adding magnesium chloride and potassium chloride into a molten salt chlorination furnace, heating to obtain liquid magnesium chloride and potassium chloride molten salt, adding the nonmagnetic substance, metallurgical coke and graphite into the liquid magnesium chloride and potassium chloride molten salt, introducing chlorine into the liquid magnesium chloride and potassium chloride molten salt to perform molten salt chlorination reaction, wherein the temperature of the molten salt chlorination reaction is 900-1000 ℃, and reacting to generate an overflow, wherein the mass ratio of the magnesium chloride to the potassium chloride to the nonmagnetic substance is 20: 10:1, wherein the mass ratio of metallurgical coke, graphite and nonmagnetic substances is 0.1: 0.1:1, the mass ratio of chlorine gas to nonmagnetic substances is 2.1: 1, carrying out four-section cooling separation on the overflow, and periodically discharging the refractory molten salt in the molten salt chlorination furnace to keep the molten salt liquid level in the molten salt chlorination furnace stable:
wherein, the four-stage cooling separation is as follows:
①, primary cooling separation, namely performing primary cooling separation on the overflow of the molten salt chlorination reaction overflowing the molten salt chlorination furnace, controlling the temperature at 360-400 ℃ to obtain high-melting-point dust slag which is unreacted low-grade niobium concentrate and gaseous chloride;
② second-stage cooling separation, which is to perform second-stage cooling separation on the gaseous chloride obtained by the first-stage cooling separation, control the temperature at 260-335 ℃ to obtain solid ferric chloride and gaseous chloride, and the purity of the ferric chloride is 96.0% by determination;
③, performing three-stage cooling separation, namely performing three-stage cooling separation on the gaseous chloride obtained by the two-stage cooling separation, controlling the temperature at 60-75 ℃ to obtain solid niobium chloride and gaseous chloride, wherein the purity of the niobium chloride is 93.3% and the recovery rate of the niobium is 80.7% through determination;
④ and four-stage cooling separation, namely, carrying out four-stage cooling separation on the gaseous chloride obtained by the three-stage cooling separation, controlling the temperature to be between 25 ℃ below zero and 50 ℃ to obtain liquid silicon tetrachloride and mixed gas of carbon dioxide and unreacted chlorine, wherein the purity of the silicon tetrachloride is 91.1 percent and the silicon recovery rate is 82.6 percent through measurement.
Example 5
The low-grade niobium concentrate of the embodiment contains Nb in mass fraction2O54.33%, Fe 12.81% and SiO228.00 percent of inner Mongolia bayan obo ore low-grade niobium concentrate is taken as a raw material, and the preparation method comprises the following steps:
(1) reduction roasting: mixing and pelletizing low-grade niobium concentrate with coke and coal powder, and then roasting, wherein the mass ratio of the low-grade niobium concentrate to the coke to the coal powder is 1: 0.15: 0.01, the roasting temperature is 850 ℃, and roasted ores are obtained;
(2) magnetic separation: crushing and grinding the roasted ore, wherein the content of the ground particle size is less than 100 meshes and is more than or equal to 96%, then carrying out magnetic separation on the ground roasted ore, wherein the magnetic separation comprises primary roughing and primary scavenging, the strength of a roughing magnetic field is 0.16T, the strength of a scavenging magnetic field is 0.27T, the roughing concentrate and the scavenging concentrate are combined to obtain iron concentrate, carrying out scavenging on roughing tailings, and the scavenging tailings are non-magnetic separation substances and are used as raw materials of a molten salt chlorination reaction, and the iron grade of the iron concentrate reaches 80.7% by determination;
(3) molten salt chlorination reaction: adding rare earth chloride into a molten salt chlorination furnace, heating to obtain liquid rare earth chloride molten salt, adding the nonmagnetic substance, metallurgical coke and graphite into the liquid rare earth chloride molten salt, introducing chlorine into the liquid rare earth chloride molten salt to perform molten salt chlorination reaction at the temperature of 700-950 ℃, and reacting to generate overflow, wherein the mass ratio of the rare earth chloride to the nonmagnetic substance is 40:1, and the mass ratio of the metallurgical coke to the graphite to the nonmagnetic substance is 0.2: 0.1:1, the mass ratio of chlorine gas to nonmagnetic substances is 4.2: 1, carrying out four-section cooling separation on the overflow, and periodically discharging the refractory molten salt in the molten salt chlorination furnace to keep the molten salt liquid level in the molten salt chlorination furnace stable:
wherein, the four-stage cooling separation is as follows:
①, primary cooling separation, namely performing primary cooling separation on the overflow of the molten salt chlorination reaction overflowing the molten salt chlorination furnace, controlling the temperature at 390-450 ℃ to obtain high-melting-point dust slag which is unreacted low-grade niobium concentrate and gaseous chloride;
② second-stage cooling separation, which is to perform second-stage cooling separation on the gaseous chloride obtained by the first-stage cooling separation, and control the temperature at 285-330 ℃ to obtain solid ferric chloride and gaseous chloride, wherein the purity of the ferric chloride is 89.9% by determination;
③, performing three-stage cooling separation, namely performing three-stage cooling separation on the gaseous chloride obtained by the two-stage cooling separation, controlling the temperature to be 75-93 ℃ to obtain solid niobium chloride and gaseous chloride, wherein the purity of the niobium chloride is 90.2% and the recovery rate of the niobium is 86.2% through determination;
④ and four-stage cooling separation, namely, carrying out four-stage cooling separation on the gaseous chloride obtained by the three-stage cooling separation, controlling the temperature to be 15-50 ℃ to obtain liquid silicon tetrachloride and mixed gas of carbon dioxide and unreacted chlorine, wherein the purity of the silicon tetrachloride is 92.7% and the silicon recovery rate is 80.9% through determination.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (8)

1. The extraction method of the low-grade niobium concentrate through reduction roasting-molten salt chlorination is characterized by comprising the following steps of:
(1) reduction roasting: mixing and roasting the low-grade niobium concentrate and a reducing agent to obtain roasted ore;
(2) magnetic separation: crushing and grinding the roasted ore, then carrying out magnetic separation, and carrying out magnetic separation to obtain iron ore concentrate and nonmagnetic substances;
(3) molten salt chlorination reaction: adding solid chloride molten salt into a molten salt chlorination furnace, heating to obtain liquid chloride molten salt, adding the nonmagnetic substance and metallurgical coke or graphite into the liquid chloride molten salt, introducing chlorine into the liquid chloride molten salt to perform molten salt chlorination reaction at the temperature of 700 ℃ for obtaining an overflow product, performing four-section cooling separation on the overflow product, and periodically discharging the hard-to-boil molten salt in the molten salt chlorination furnace to keep the liquid level of the molten salt in the molten salt chlorination furnace stable;
wherein, in the four-stage cooling separation, the temperature of the first-stage cooling separation is 350-450 ℃, the temperature of the second-stage cooling separation is 250-340 ℃, the temperature of the third-stage cooling separation is 60-240 ℃, and the temperature of the fourth-stage cooling separation is-30-50 ℃.
2. The method for extracting by reductive roasting-molten salt chlorination of low-grade niobium concentrate according to claim 1, characterized in that the low-grade niobium concentrate is Nb with mass fraction of 2-15%2O5And iron concentrate with the mass fraction of 15-50%.
3. The reducing roasting-molten salt chlorination extraction method of the low-grade niobium concentrate according to claim 1 or 2, wherein the reducing agent in the step (1) is one or more of coke, coal powder and petroleum coke, and the mass ratio of the low-grade niobium concentrate to the reducing agent is 1: 0.15-0.35.
4. The method for extracting the low-grade niobium concentrate through the reductive roasting-molten salt chlorination as claimed in claim 1 or 2, wherein the roasting temperature in the step (1) is 700-1300 ℃.
5. The reducing roasting-molten salt chlorination extraction method of low-grade niobium concentrate as claimed in claim 1, wherein the content of roasted ore ground with particle size less than 100 meshes in step (2) is more than or equal to 50%.
6. The reducing roasting-molten salt chlorination extraction method of the low-grade niobium concentrate as claimed in claim 1 or 5, wherein the magnetic field intensity of the magnetic separation in the step (2) is 0.15-0.6T.
7. The reductive roasting-molten salt chlorination extraction method of low-grade niobium concentrate of claim 1, wherein the solid chloride molten salt in step (3) is one or more of alkali metal chloride, alkaline earth metal chloride and rare earth chloride.
8. The reducing roasting-molten salt chlorination extraction method of the low-grade niobium concentrate as claimed in claim 7, wherein the mass ratio of the solid chloride molten salt to the nonmagnetic substance in the step (3) is 30-40:1, and the mass ratio of the nonmagnetic substance to the metallurgical coke or graphite is 1: 0.1-0.35, and the mass ratio of the chlorine gas to the nonmagnetic substance is 2-4.5: 1.
CN201811121174.8A 2018-09-25 2018-09-25 Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate Expired - Fee Related CN109136536B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811121174.8A CN109136536B (en) 2018-09-25 2018-09-25 Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811121174.8A CN109136536B (en) 2018-09-25 2018-09-25 Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate

Publications (2)

Publication Number Publication Date
CN109136536A CN109136536A (en) 2019-01-04
CN109136536B true CN109136536B (en) 2020-05-22

Family

ID=64812465

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811121174.8A Expired - Fee Related CN109136536B (en) 2018-09-25 2018-09-25 Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate

Country Status (1)

Country Link
CN (1) CN109136536B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102872968A (en) * 2012-09-18 2013-01-16 镇康县金宏矿业有限公司 Ore dressing method for separating ferrocolumbium
CN102994738A (en) * 2012-12-06 2013-03-27 内蒙古科技大学 Method for preparing niobium-enriched ore by employing X-fluorescence sorting-microwave carbon thermal reduction
CN104894363A (en) * 2015-06-24 2015-09-09 东北大学 Method for using low-grade niobium concentrate to produce niobium-iron alloy and rare earth double sulfate salt
CN105154659A (en) * 2015-10-18 2015-12-16 内蒙古科技大学 Method for synchronously extracting iron and niobium from Bayan Obo low-grade ores

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52128818A (en) * 1976-04-07 1977-10-28 Awamura Kinzoku Kougiyou Kk Tin removing from niobium ore containing tin

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102872968A (en) * 2012-09-18 2013-01-16 镇康县金宏矿业有限公司 Ore dressing method for separating ferrocolumbium
CN102994738A (en) * 2012-12-06 2013-03-27 内蒙古科技大学 Method for preparing niobium-enriched ore by employing X-fluorescence sorting-microwave carbon thermal reduction
CN104894363A (en) * 2015-06-24 2015-09-09 东北大学 Method for using low-grade niobium concentrate to produce niobium-iron alloy and rare earth double sulfate salt
CN105154659A (en) * 2015-10-18 2015-12-16 内蒙古科技大学 Method for synchronously extracting iron and niobium from Bayan Obo low-grade ores

Also Published As

Publication number Publication date
CN109136536A (en) 2019-01-04

Similar Documents

Publication Publication Date Title
CN103805726B (en) A kind of method using rotary hearth furnace pearl iron process to fully utilize iron red mud
CN109022773B (en) Method for comprehensively utilizing titanium concentrate
CN103255255A (en) Gas-based shaft furnace direct reduction-electric furnace smelting separation process of vanadium titano-magnetite
CN103695631B (en) A kind of beneficiation enrichment technique of ferrotianium oxidized ore
CN105154659A (en) Method for synchronously extracting iron and niobium from Bayan Obo low-grade ores
CN106854702A (en) The method that the conversion of one step separates iron, vanadium and titanium in sefstromite concentrate
CN101565768A (en) Method for producing ferrous powder and co-production titanium slag by rapidly reducing titanium placer pellets by rotary hearth furnace
CN103088208A (en) Method for treating manganese-containing and phosphorus-containing hematite
CN106884089A (en) Method for recovering vanadium from non-blast furnace titanium slag
CN104894363A (en) Method for using low-grade niobium concentrate to produce niobium-iron alloy and rare earth double sulfate salt
CN105112678A (en) Method for magnetically separating and smelting chromium-iron alloy by vanadium extraction from vanadium-chromium slag and reduction of tailings
CN106065436A (en) A kind of method and system processing vanadium slag
CN100478477C (en) Method for extracting nickel iron alloy from laterite ore
CN107142378A (en) The extracting method of lead in a kind of sintering flue dust
CN107805717A (en) A kind of system and method that aluminium-scandium alloy is prepared using red mud
WO2023193714A1 (en) Method and system for coupling copper slag recycling with co2 mineralization based on industrial solid waste
CN109136536B (en) Reduction roasting-molten salt chlorination extraction method of low-grade niobium concentrate
CN105567973A (en) Method for preparing ferro-nickel alloy and ferrotungsten-molybdenum alloy from waste material containing tungsten, molybdenum and nickel
CN109182782B (en) Boiling chlorination extraction method of niobium-tantalum concentrate
CN106702165B (en) A method of leaching niobium scandium from tailing
CN109097558B (en) Reduction roasting-molten salt chlorination extraction method of multi-metal composite concentrate
CN108893572A (en) A kind of method of valuable constituent element comprehensive reutilization in paigeite
CN115369260A (en) Method for producing high-grade zinc oxide product from low-grade zinc oxide ore and product thereof
CN107419090A (en) A kind of separation method of vanadium titano-magnetite and application
CN109207746B (en) Molten salt chlorination extraction method of low-grade niobium concentrate

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20200522

Termination date: 20210925

CF01 Termination of patent right due to non-payment of annual fee