CN109112292B

CN109112292B - Method for co-producing barium sulfide and pentavalent vanadium slag by roasting vanadium-containing stone coal and barite

Info

Publication number: CN109112292B
Application number: CN201811173627.1A
Authority: CN
Inventors: 赵卓成; 李盛龙; 付荣华; 赵国旗; 彭斌
Original assignee: Hubei Gucheng Xinhe Co ltd
Current assignee: HUBEI GUCHENG XINHE CO.,LTD.; Zhushan Qinba barium salt Co., Ltd
Priority date: 2018-10-09
Filing date: 2018-10-09
Publication date: 2021-07-16
Anticipated expiration: 2038-10-09
Also published as: CN109112292A

Abstract

The invention relates to a method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag, which comprises the following steps: s1, mixing barite, vanadium-containing stone coal and coke according to a certain proportion, and crushing to 60-80 meshes; s2, preparing the mixed materials into a ball-shaped material with the diameter of 10-15 mm; s3, roasting the spherical materials at the temperature of 1000-1100 ℃ for 80-100 minutes, and then preserving heat at the temperature of 900 ℃ for 2 hours; s4, leaching the roasted pellet material in a leaching pool by hot water to obtain barium sulfide; s5, after the waste residue is washed by hot water, soaking and extracting a vanadium-containing solution by using dilute sulfuric acid as a raw material for extracting vanadium pentoxide; according to the invention, barium sulfide and pentavalent vanadium slag are obtained by treating barite, vanadium-containing stone coal and coke in certain process steps, roasting in a vertical kiln, setting certain process conditions and subsequent process steps, so that the roasting effect and the raw material utilization rate are improved, and the method is energy-saving and environment-friendly.

Description

Method for co-producing barium sulfide and pentavalent vanadium slag by roasting vanadium-containing stone coal and barite

Technical Field

The invention relates to the technical field of vanadium pentoxide production, in particular to a method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag.

Background

After mixing barite and anthracite coal, roasting in rotary kiln to produce black barium sulfide ash, and leaching out barium sulfide from black ash to be used as raw material for producing various barium salts. This method has long been known. Is also the main method for roasting the barite at home and abroad at present. The reaction production principle in the rotary kiln is as follows:

2C+O₂＝2CO；

4CO+BaSO₄＝BaS+4CO₂；

if the oxygen is excessive, there is also the following oxidation reaction:

BaS+3/2O₂+CO₂＝BaCO₃+SO₂；

from the principle, the method is a reduction reaction, and the natural barium sulfate component in the barite and the fixed carbon react at 1050-1100 ℃ to generate water-soluble barium sulfide and carbon dioxide. More reactions are the reaction of carbon with oxygen to form carbon monoxide, which in turn reacts with barium sulfate to form barium sulfide and carbon dioxide. Although the production by the rotary kiln has a long history, the method has the following defects:

1. the barite roasting reduction reaction should be carried out in a reducing atmosphere, but a large amount of air needs to be added for spraying and burning of the rotary kiln coal powder, and meanwhile, air is easy to leak from the discharge end of the kiln, so that the reducing atmosphere in the rotary kiln is difficult to maintain, and when the oxygen is excessive, barium carbonate and sulfur dioxide are easy to generate. In fact, black ash is burnt out by the rotary kiln, and the content of barium sulfide in the black ash is only about 55 percent generally. The barium carbonate content in the residue after hot water leaching is 20-30%, so that a large amount of barium is lost into the waste residue, and the barium carbonate has toxicity and discharges sulfur dioxide, so that the environment pollution is also seriously caused;

2. when the barite and the anthracite are roasted in a rotary kiln, the barite and the anthracite are generally mixed and crushed to the grain size of 3-5 mm. In fact, a large amount of powdery material is easily produced during the crushing process, and when the mixture is added from the kiln tail, a considerable part of fine powder is brought into the settling chamber and the dust remover by the flue gas. In particular, the anthracite powder is more serious because the density is low and the anthracite powder is taken away, so that not only is the material loss brought, but also the ingredient ratio of barite and anthracite is seriously damaged. Resulting in reduced roasting effect and high raw material consumption.

Disclosure of Invention

The invention aims to overcome the defects in the roasting process of a rotary kiln and obtain the energy-saving and environment-friendly method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag, wherein the roasting effect and the utilization rate can be improved.

The invention is realized by the following technical scheme:

the method for co-producing barium sulfide and pentavalent vanadium slag by roasting vanadium-containing stone coal and barite comprises the following steps:

s1, mixing barite, vanadium-containing stone coal and coke according to a certain proportion, and crushing to 60-80 meshes;

s2, preparing the mixed materials into a ball-shaped material with the diameter of 10-15 mm;

s3, roasting the spherical materials at the temperature of 1000-1100 ℃ for 80-100 minutes, and then preserving heat at the temperature of 900 ℃ for 2 hours;

s4, leaching the roasted pellet material in a leaching pool by hot water to obtain barium sulfide;

and S5, after the waste residue is washed by hot water, soaking and extracting a vanadium-containing solution by using dilute sulfuric acid to serve as a raw material for extracting vanadium pentoxide.

The invention is further improved in that in the step S1, before the barite, the vanadium-containing stone coal and the coke are mixed, the materials are respectively crushed.

The invention is further improved in that in the step S1, the method further comprises the steps of adding 10-15% of water into the mixed materials, and placing the materials into a stirrer to be stirred and mixed uniformly.

In a further improvement of the present invention, in the step S2, a balling machine is used to support the material in pellet form.

In a further improvement of the invention, in the step S3, the vertical kiln is used for roasting, the material is fed from the upper part of the vertical kiln, and the material is discharged from the lower part of the vertical kiln.

The invention is further improved in that a drying section, a preheating section, a roasting section and a heat preservation section are sequentially arranged in the vertical kiln from top to bottom.

The invention is further improved in that the temperature of the drying section is set to be 350-500 ℃, the temperature of the preheating section is set to be 500-800 ℃, the temperature of the roasting section is set to be 1000-1100 ℃, and the temperature of the heat preservation section is set to be 850-950 ℃.

In a further improvement of the present invention, in the step S4, the hot water temperature is set to 70-75 ℃.

The further improvement of the invention is that in the step S5, the leaching residue is washed for 3-4 times, when the residual barium sulfide is less than 0.5%, 2% dilute sulfuric acid solution is added for soaking, the soaking time is 10-12 hours, and pentavalent vanadium in the residue is dissolved into the acid solution to be used as a raw material for extracting vanadium pentoxide.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, barium sulfide and pentavalent vanadium slag are obtained by treating barite, vanadium-containing stone coal and coke in certain process steps, roasting in a vertical kiln, setting certain process conditions and subsequent process steps, so that the roasting effect and the raw material utilization rate are improved, and the method is energy-saving and environment-friendly.

Drawings

FIG. 1 is a process flow diagram in one embodiment of the invention;

FIG. 2 is a schematic illustration of a vertical kiln firing process in accordance with one embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in fig. 1 to 2, the method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag comprises the following steps:

In the specific implementation, in the step S1, before the barite, the vanadium-containing stone coal and the coke are mixed, the crushing step is further performed on each material.

In specific implementation, the step S1 further includes adding 10-15% of water into the mixed material, and placing the mixture into a stirrer to be uniformly stirred and mixed.

In specific implementation, in step S2, a pelletizer is used to support the pelletized material.

In the specific implementation, in the step S3, a vertical kiln is used for roasting, the material is fed from the upper part of the vertical kiln, and the material is discharged from the lower part of the vertical kiln.

In specific implementation, a drying section, a preheating section, a roasting section and a heat preservation section are sequentially arranged in the vertical kiln from top to bottom.

In specific implementation, the temperature of the drying section is set to be 350-500 ℃, the temperature of the preheating section is set to be 500-800 ℃, the temperature of the roasting section is set to be 1000-1100 ℃, and the temperature of the heat preservation section is set to be 850-950 ℃.

In a specific implementation, in step S4, the hot water temperature is set to 70-75 ℃.

In the specific implementation, in the step S5, the leaching residue is washed with water for 3-4 times, when the residual barium sulfide is less than 0.5%, a 2% dilute sulfuric acid solution is added for soaking for 10-12 hours, and pentavalent vanadium in the residue is dissolved in the acid solution to be used as a raw material for extracting vanadium pentoxide.

In the technical scheme, the invention provides a novel vertical kiln roasting method. The method comprises mixing barite, vanadium-containing stone coal and coke at a certain ratio, pulverizing to 60-80 mesh, and making into spherical material with diameter of 10-15mm with a ball forming mill. The pellets are added into a vertical kiln by a distributing machine, are roasted for 1.5 hours at the temperature of 1000-1100 ℃ from top to bottom, are subjected to heat preservation for 2 hours at the temperature of 900 ℃ and are discharged from the bottom. The barium sulfide is leached out of the sintered pellets in a leaching pool by hot water, and the waste residue is washed by hot water and then is soaked in dilute sulphuric acid to extract vanadium-containing solution which is used as a raw material for extracting vanadium pentoxide. Vanadium pentoxide extracted as a byproduct is an important material and has wide application in the fields of steel, national defense and the like. The waste residue after acid leaching and water washing is a high-quality material for producing cement.

The working principle of the invention is as follows:

as shown in figure 1, vanadium-containing stone coal, barite and coke are respectively crushed, added into a stirrer according to a certain proportion, added with 10-15% of water, stirred and mixed evenly, added into a balling disc and extruded into balls. The pellets are added into a vertical roasting kiln for roasting, the roasting temperature is controlled at 1000-1100 ℃, and the reaction time is controlled at 80-100 minutes. At the temperature, barium sulfate in barite, fixed carbon in stone coal and coke are subjected to reduction reaction to generate barium sulfide and carbon dioxide. When the barium pellets are sintered, the raw materials are more uniformly mixed with the raw materials for the converter roasting, the mixing proportion is more accurate, and the phenomenon that powder is taken away along with flue gas is completely avoided in the roasting process. Meanwhile, the crushed particle size of the raw material is smaller than 0.1mm, and the barium sulfate in the coke and the barite is better combined. When the barite is roasted in a converter, the diameter of raw material particles is 3-5mm, and the reaction contact surface is small, so that the barite conversion is not facilitated. In the reducing atmosphere, the barium sulfate component in the barite reacts with the fixed carbon, so that the problem of excessive oxygen is avoided, and the content of barium carbonate in the burnt product is greatly reduced.

At high temperature, the stone coal fixed carbon in the raw material is reacted with barium sulfate and used as a part of reduced carbon. Meanwhile, the low-valence vanadium embedded in the stone coal crystal grid is oxidized by oxygen under the catalysis of barium, trivalent vanadium and quadrivalent vanadium are oxidized into pentavalent vanadium, and the pentavalent vanadium has good acid solubility and can be effectively leached out.

The reduction reaction is carried out in a reducing atmosphere during the barite calcination reaction. However, the conversion of low-valence vanadium into high-valence vanadium needs to be carried out in an oxidizing atmosphere. In the mixed roasting, the barium sulfate is converted into barium sulfide even without oxygen, and only the reaction temperature is required to be provided. In order to maintain the reaction temperature during the calcination process, a combustion process must be present, and thus the calcination process cannot be achieved without the participation of oxygen. So that the oxygen must be excessive during the actual firing in the rotary kiln, which also promotes the conversion of part of the barium sulfate into barium carbonate, thereby causing a waste of raw materials.

The vertical kiln roasting process is different from the rotary kiln, and as shown in figure 2, in the vertical kiln roasting process, the material balls move from top to bottom and sequentially comprise a drying section, a preheating section, a roasting section and a cooling section from top to bottom. The pellets are dried by tail gas rising from the kiln in the drying section to remove moisture in the pelletizing process. It is heated to 800 c in the preheating stage, at which point the barium sulfate and carbon begin to react. In the roasting section, the temperature is as high as 1000-1100 ℃, and the reaction is mainly carried out according to the solid-solid reaction of barium sulfate and carbon to generate carbon dioxide and barium sulfide. And vanadium in the material reacts with residual oxygen from bottom to top under the catalysis of barium, and part of vanadium begins to be converted into high-valence vanadium from low-valence vanadium. Because the residual oxygen reacts with the low-valence vanadium firstly, the oxygen content on the surface of the generated barium sulfide is very low, and the barium sulfide and the oxygen are inhibited from continuously reacting and converting into barium carbonate, so the barium carbonate is hardly detected in the sintering material, and the loss of barium element is effectively prevented.

The roasted material continuously goes downwards and enters a heat preservation section. The temperature of the heat preservation section is 850-950 ℃, at the moment, the oxygen in the blowing air generates oxidation reaction with the vanadium in the heat preservation section and the material, and the low-valence vanadium is continuously oxidized into high-valence vanadium. The material enters the outlet and the reaction is terminated.

The calcined material is added into a leaching pool, and is leached by hot water at 70-75 ℃ to extract water-soluble barium sulfide. Barium sulfide is a basic raw material for preparing barium salt, and can be used for producing barium carbonate, barium chloride, barium sulfate, barium hydroxide and other products.

And washing the leaching residue for 3-4 times, adding 2% dilute sulfuric acid solution for soaking when the residual barium sulfide is less than 0.5%, and dissolving the pentavalent vanadium in the residue into the acid solution for 10-12 hours. And regulating the pH value of the acidic solution, performing ion exchange, adding ammonium bicarbonate for precipitation, roasting and the like to prepare vanadium pentoxide.

In the scheme, the shaft kiln process has strict requirements on the proportion of the raw materials, the proportion design meets the requirement that barite and fixed carbon react to generate barium sulfide, and the vanadium-containing stone coal has higher addition amount, so that a certain yield of vanadium pentoxide is ensured.

According to the production experience of barium sulfide generated by roasting barite, the fixed carbon of the barite with 85% of barium sulfate content is required to be about 15-16% of the barite. The vanadium-containing stone coal generally has a fixed carbon content of 10-20%. The fixed carbon content of the coke is about 90 percent generally. Thus, multiple sets of formulations were designed.

Test formula one (parts by weight):

barite (barium sulfate content 85%): 100 portions of

Vanadium-containing stone coal (fixed carbon content 15%, vanadium content 0.9%): 90 portions of

Bituminous coal (calorific value 6000 kcal/kg): 10 portions of

The fixed carbon in the formula is 13.5, while the fixed carbon required for barite calcination is 85 x 0.16-13.6. The bituminous coal in the formula accounts for 10-12% of the barite and is mainly used for ensuring the roasting temperature.

According to the first formula, 100 g of barite, 90 g of stone coal and 10 g of bituminous coal are weighed, crushed to 60-80 meshes by a crusher, placed in a ceramic crucible, roasted for 40 minutes at 850-950 ℃ in a muffle furnace, and then heated to 1050 ℃ for roasting for 60 minutes. The detection results are as follows:

content of barium sulfide: 51 percent;

and (3) vanadium content: 0.79 percent;

content of barium carbonate: 1.3 percent;

unreacted barium sulfate: 1.2 percent;

the rotary kiln with high barium sulfide content in the burnt material has the advantage that the total amount of ash is less because stone coal is not added in the rotary kiln. But the barium carbonate content is 90% lower than in the rotary kiln, and the unreacted barium sulfate is also much lower than in the rotary kiln. The vanadium content is reduced because the total content of barium sulfide black ash contained in the discharged material of the vertical kiln is large.

Test formula two (parts by weight):

barite (barium sulfate content 80%): 100 parts of (A);

vanadium-containing stone coal (fixed carbon content 10%, vanadium content 0.9%): 80 parts of a mixture;

coke (fixed carbon content 90%): 5.5 parts;

bituminous coal (calorific value 6000 kcal/kg): 10 parts of (A);

the fixed carbon purity in the formula is 80 × 0.1+5.5 × 0.9 ═ 12.95, and the fixed carbon required for barite calcination is 80 × 0.16 ═ 12.8. The bituminous coal in the formula accounts for 10-12% of the barite to ensure the roasting temperature.

The test is carried out in the same condition, and the results are as follows:

content of barium sulfide: 53.5 percent;

and (3) vanadium content: 0.82%;

content of barium carbonate: 1.5 percent;

unreacted barium sulfate: 1.4 percent;

the two formulas are similar to each other in preliminary result and expectation through tests, and can be used for carrying out production roasting tests.

The roasting and leaching conditions are as follows:

temperature of the roasting zone: 1050 ℃;

roasting time: 60-90 minutes;

a heat preservation area: 900 ℃ and 950 ℃;

oxidation time of the heat preservation area: 100-;

the fineness of the raw materials is as follows: 60-80 meshes;

balling diameter: 10-15 mm;

the hot water leaching temperature is as follows: 70-75 ℃;

hot water leaching time: 2 hours;

residual amount of barium sulfide after washing: less than 0.5%;

acid leaching time: for 12 hours.

On the basis of the technical principle and the technical scheme, the invention is taken as an embodiment:

1. with a cross-sectional area of 10m²The special shaft kiln roasting for roasting the conventional vanadium ore;

2. the raw material ratio is as follows: 100 tons of barite with the content of 82 percent, 50 tons of stone coal with the content of fixed carbon of 9 percent, 0.96 percent of vanadium, 9 tons of coke with the content of carbon of 92 percent and 9 tons of high-quality bituminous coal;

3. mixing the weighed raw materials in a stock ground, crushing the raw materials in a jaw crusher, and grinding the crushed raw materials in a Raymond mill unit, wherein the fineness of the powder is kept at 60-80 meshes without opening an analyzer. Adding the crushed materials into a vertical stirrer, adding water, wherein the water addition amount is 13% of the total amount, feeding the stirred materials into a balling disc, and spraying a little water to ensure the balling effect. The diameter is controlled to be 10-15 mm;

4. adding the pellet material into a roasting kiln for roasting, and controlling the roasting reduction temperature to be about 1050 ℃. The temperature of the oxidation zone is controlled to be about 900 ℃. The reduction roasting time is 1.5 hours, and the retention time of the heat preservation oxidation zone is 2 hours.

5. The main indexes of the detected sintering material are as follows:

content of barium sulfide: 58 percent;

and (3) vanadium content: 1.01 percent;

residual amount of barium sulfate: 0.99 percent;

content of barium carbonate: 0.76 percent;

6. the sintered material is soaked in hot water, and the content of residual vanadium in the barium sulfide solution is detected to be 0.08 percent, so that the barium sulfide is not influenced to produce other barium salts. The leaching rate of vanadium after acid leaching of the calcined material is further detected, and the detection result is 81.2%.

As another embodiment of the present invention:

1. with a cross-sectional area of 20m²The special shaft kiln roasting for roasting the conventional vanadium ore;

2. the raw material ratio is as follows: 100 tons of barite with the content of 88 percent, 100 tons of stone coal with the content of fixed carbon of 9 percent and the content of vanadium of 0.70 percent, 4.5 tons of coke with the content of carbon of 90 percent and 9 tons of high-quality bituminous coal;

3. mixing the weighed raw materials in a stock ground, crushing the raw materials in a jaw crusher, and grinding the crushed raw materials in a Raymond mill unit, wherein the fineness of the powder is kept at 60-80 meshes without opening an analyzer. Adding the crushed materials into a vertical stirrer, adding water, wherein the water addition amount is 15% of the total amount, feeding the stirred materials into a balling disc, and spraying a little water to ensure the balling effect. The diameter is controlled to be 10-15 mm;

4. adding the pellet material into a roasting kiln for roasting, and controlling the roasting reduction temperature to be about 1100 ℃. The temperature of the oxidation zone is controlled to be about 950 ℃. The reduction roasting time is 1.5 hours, and the retention time in the heat preservation oxidation zone is 4 hours;

5. the main indexes of the detected sintering material are as follows:

content of barium sulfide: 53 percent;

and (3) vanadium content: 0.94 percent;

residual amount of barium sulfate: 0.75 percent;

content of barium carbonate: 0.56 percent;

6. the sintered material is soaked in hot water, and the content of residual vanadium in the barium sulfide solution is detected to be 0.04 percent, so that the barium sulfide is not influenced to produce other barium salts. The leaching rate of vanadium after acid leaching of the calcined material is further detected, and the detection result is 83.6%.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. The method for co-producing barium sulfide and pentavalent vanadium slag by roasting vanadium-containing stone coal and barite is characterized by comprising the following steps of:

the concrete raw material ratio is as follows: 100 tons of barite with the content of 82 percent, 50 tons of stone coal with the content of fixed carbon of 9 percent, 0.96 percent of vanadium, 9 tons of coke with the content of carbon of 92 percent and 9 tons of high-quality bituminous coal;

or the raw materials are mixed as follows: 100 tons of barite with the content of 88 percent, 100 tons of stone coal with the content of fixed carbon of 9 percent and the content of vanadium of 0.70 percent, 4.5 tons of coke with the content of carbon of 90 percent and 9 tons of high-quality bituminous coal;

the method specifically comprises the following steps: roasting by using a vertical kiln, feeding materials from the upper part of the vertical kiln, and discharging materials from the lower part of the vertical kiln; a drying section, a preheating section, a roasting section and a heat preservation section are sequentially arranged in the vertical kiln from top to bottom; the temperature of the drying section is set to be 350-500 ℃, the temperature of the preheating section is set to be 500-800 ℃, the temperature of the roasting section is set to be 1000-1100 ℃, and the temperature of the heat preservation section is set to be 850-950 ℃;

2. The method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag according to claim 1, which is characterized by comprising the following steps: in the step S1, before the barite, the vanadium-containing stone coal and the coke are mixed, the crushing step is further performed on the materials respectively.

3. The method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag according to claim 1, which is characterized by comprising the following steps: and in the step S1, adding 10-15% of water into the mixed material, and putting the mixed material into a stirrer to be stirred and mixed uniformly.

4. The method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag according to claim 1, which is characterized by comprising the following steps: in step S2, a pelletizer is used to support the pelletized material.

5. The method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag according to claim 1, which is characterized by comprising the following steps: in the step S4, the hot water temperature is set to 70 to 75 ℃.

6. The method for roasting vanadium-containing stone coal and barite to co-produce barium sulfide and pentavalent vanadium slag according to claim 1, which is characterized by comprising the following steps: in the step S5, the leaching residue is washed for 3-4 times, when the residual barium sulfide is less than 0.5%, a 2% dilute sulfuric acid solution is added for soaking for 10-12 hours, and pentavalent vanadium in the residue is dissolved in the acid solution to be used as a raw material for extracting vanadium pentoxide.