阅读说明：本技术 利用链篦机和回转窑焙烧含钒物料的方法 (Method for roasting vanadium-containing material by using chain grate and rotary kiln ) 是由 王显云 邹正强 吴宝林 杨灵锁 罗林军 凃志洪 于 2019-11-29 设计创作，主要内容包括：本发明涉及提钒化工方法领域,尤其是一种大大提高了钒的转化率和转浸率的利用链篦机和回转窑焙烧含钒物料的方法,包括如下步骤：a、将含钒物料破碎到所需的粒度,然后与添加剂混合,随后进行机械活化,得到混合料；b、用滚筛机均匀地将成型物料布置在链篦机中,在链篦机中进行干燥、固化和强化；c、随后成型物料进入回转窑中进行集中高温焙烧,出料后得到含钒成型熟料,含钒成型熟料破碎到所需粒度后,经过水浸或酸浸后得到含钒浸出液,用于后续沉钒。本发明通过利用链篦机和回转窑来进行含钒物料的焙烧,具有工艺简单易用、设备要求低、操作方便、适应范围广、成本低的技术优势,尤其适用于含钒物料焙烧工艺之中。(The invention relates to the field of vanadium extraction chemical methods, in particular to a method for roasting vanadium-containing materials by using a chain grate and a rotary kiln, which greatly improves the conversion rate and the rotary leaching rate of vanadium, and comprises the following steps: a. crushing the vanadium-containing material to the required granularity, then mixing the vanadium-containing material with an additive, and then carrying out mechanical activation to obtain a mixture; b. uniformly arranging the molding material in a chain grate machine by using a roller screen machine, and drying, curing and reinforcing in the chain grate machine; c. and then the formed material enters a rotary kiln for concentrated high-temperature roasting, vanadium-containing formed clinker is obtained after discharging, and the vanadium-containing formed clinker is crushed to the required granularity and then subjected to water leaching or acid leaching to obtain vanadium-containing leachate for subsequent vanadium precipitation. The method provided by the invention is used for roasting the vanadium-containing material by utilizing the chain grate and the rotary kiln, has the technical advantages of simple and easy-to-use process, low equipment requirement, convenience in operation, wide application range and low cost, and is particularly suitable for the roasting process of the vanadium-containing material.)

1. The method for roasting vanadium-containing materials by utilizing the chain grate and the rotary kiln is characterized by comprising the following steps:

a. firstly, crushing a vanadium-containing material to a required granularity, then mixing the vanadium-containing material with an additive, and then carrying out mechanical activation to obtain a mixture;

b. after the mixture is prepared and molded and powder is removed, the molded material is uniformly arranged in a chain grate (9) by a roller screen machine, and the drying, curing and strengthening are carried out in the chain grate (9) by sequentially passing through an air blowing area (2), an air exhausting area (3) and a preheating area (4);

c. and then the formed material enters a rotary kiln (8) for concentrated high-temperature roasting, vanadium-containing formed clinker is obtained after discharging, and the vanadium-containing formed clinker is crushed to the required granularity and then subjected to water leaching or acid leaching to obtain vanadium-containing leachate for subsequent vanadium precipitation.

2. The method for roasting vanadium-containing materials by using a grate and a rotary kiln as claimed in claim 1, wherein: the vanadium-containing material in the step a is converter vanadium slag, vanadium-containing stone coal, vanadium-containing steel slag or vanadium-containing waste catalyst.

3. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: the additive in the step a comprises a sodium additive or a calcification additive, wherein the sodium additive is sodium carbonate, sodium bicarbonate, sodium sulfate or sodium bisulfate; the calcification additive is limestone, calcium oxide or calcium sulfate.

4. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: in the step a, the molar ratio of the additive to the vanadium is 0.5: 1-5: 1.

5. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: in the step a, the mechanical activation time is 10-120 min.

6. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: in the step b, the molding size is 5-50 mm.

7. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: in the step b, the thickness of the material is 50-300 mm.

8. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: in the step b, the temperature of the air blowing area (2) is 200-300 ℃.

9. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: in the step b, the curing time is 30-100 min.

10. The method for roasting vanadium-containing materials using a grate and a rotary kiln as claimed in claim 1 or 2, wherein: in the step c, the high-temperature roasting temperature is 820-1000 ℃, the high-temperature roasting time is 60-180 min, and the discharging temperature is 600-900 ℃.

Technical Field

The invention relates to the field of vanadium extraction chemical methods, in particular to a method for roasting vanadium-containing materials by using a chain grate and a rotary kiln.

Background

Vanadium has various chemical valence states in nature, and is easy to replace certain elements in a form of a homogeneous image to enter a mineral phase, so that the structural composition of the vanadium-containing phase is complex and changeable. The vanadium slag and the stone coal are used as main vanadium-containing resources in China, and the vanadium extraction process is similar. Research results show that vanadium in vanadium slag of the converter exists in vanadium-containing spinel, and vanadium in stone coal exists in vanadium-containing mica. The vanadium-containing spinel structure and the vanadium mica structure are relatively stable, the crystal lattice structure of the vanadium-containing mica can hardly be damaged by adopting an unreinforced leaching process, and vanadium can not be dissolved into a solution. The main principle of the existing vanadium extraction process is to destroy the structure of vanadium-containing spinel or vanadium-containing mica, and then the vanadium-containing spinel or vanadium-containing mica enters a solution for further extraction. With the increasing demand of the global vanadium market and the progress of scientific research level, researchers have conducted a great deal of research make internal disorder or usurp on vanadium extraction processes, including extraction of vanadium by sodium roasting, extraction of vanadium by calcified roasting, and blank oxidation.

The most typical process in vanadium extraction from vanadium slag in a converter is a sodium roasting-water vanadium leaching process, and the most critical process for determining the vanadium yield of the whole process is a roasting conversion process. In the traditional roasting process, in order to improve the oxidation rate and high-efficiency conversion of vanadium, converter vanadium slag must be prepared into very fine powder, but under the high-temperature action of an additive, a large amount of low-melting-point substances are generated, so that large-area bonding and agglomeration of vanadium-containing materials are caused, the vanadium conversion rate is reduced, and the production cannot be normally operated. Therefore, in order to reduce or avoid the bonding phenomenon of the vanadium-containing materials in the roasting process, residues or clinkers after vanadium extraction are added in the material mixing process, so that the large-area bonding of the materials is reduced, but the recovery rate of vanadium and the utilization rate of equipment are sacrificed.

One of the existing technical schemes is to adopt industrial soda as an additive and take the mixture of converter vanadium slag and sodium-modified vanadium extraction water leaching slag as a raw material to carry out vanadium extraction test research. The method comprises the following steps: mixing the vanadium-containing mixed material with soda powder, heating for 1h at 760 ℃ in a muffle furnace, heating the material for a certain time at a specified roasting temperature, and investigating the influence of conditions such as alkali ratio, the ratio of water leaching slag to converter vanadium slag, roasting temperature and roasting time on the vanadium extraction process. The result shows that the leaching rate of vanadium can reach 90% under certain conditions, and the two-step roasting process can completely carry out the reaction, thereby effectively reducing the content of vanadium in the residue, but the process still does not solve the bottleneck problems of material adhesion and caking in the roasting process.

The other technical scheme is that the current situations that the charging structure of a multi-hearth furnace is unreasonable, sticky cakes and adhesion frequently occur in the production of vanadium pentoxide are analyzed, the furnace material structure is optimized, the roasting condition of the multi-hearth furnace at the temperature of 750-800 ℃ can be smooth, and necessary conditions are provided for improving the roasting conversion rate of vanadium slag in the converter, but the roasting environment is performed under the condition of roasting powder, the adhesion of the vanadium slag material of the powder converter is inevitably generated, so that the production is unsmooth, the efficiency is low, and the vanadium conversion rate is low.

The other technical scheme is that the converter vanadium slag is subjected to physical and chemical analysis, and systematic experiments are carried out in a laboratory according to the characteristics of the converter vanadium slag and the multi-hearth furnace. According to the result of the pilot plant test, the roasting process of the multi-hearth furnace is improved, the conversion rate of vanadium slag of the multi-hearth furnace roasting converter reaches 86.6%, the TV of leached residues is reduced to about 1.2%, but the conversion rate of vanadium is far lower than the level of 90%, and the high-efficiency extraction of vanadium is difficult to realize.

Although the roasting of the vanadium slag fine powder by the multi-hearth furnace is feasible, the utilization efficiency of the multi-hearth furnace is low on the whole, the amount of the vanadium slag fine powder processed by a single device per hour is only 3-4 t/h, materials are often bonded, blocked and blocked in the operation process, the operation is not smooth, the bonding problem needs to be processed by a large amount of manpower, the temperature gradient in the multi-hearth furnace is also in an unstable state, and the vanadium conversion rate is low.

In addition, the rotary kiln is also an important device for roasting vanadium-containing materials, and enterprises at home and abroad mostly adopt the device for roasting the vanadium-containing materials. However, in the process of roasting powdery vanadium-containing materials in the rotary kiln, particularly directly roasting vanadium slag in the powdery converter, a large amount of low-melting-point materials are formed at 550-700 ℃, heat is rapidly released, and the materials are easily bonded to cause ring formation of the rotary kiln. Therefore, in order to ensure the operation of the equipment, the process of adding return slag or clinker is usually used for ensuring the operation of the equipment, but the problems of low vanadium conversion rate and low equipment utilization rate are brought.

Disclosure of Invention

The invention aims to solve the technical problem of providing a method for roasting vanadium-containing materials by using a chain grate and a rotary kiln, which not only solves the problems of material adhesion and concentrated heat release, but also greatly improves the conversion rate and the rotary leaching rate of vanadium.

The technical scheme adopted by the invention for solving the technical problems is as follows: the method for roasting vanadium-containing materials by utilizing the chain grate and the rotary kiln comprises the following steps: a. firstly, crushing a vanadium-containing material to a required granularity, then mixing the vanadium-containing material with an additive, and then carrying out mechanical activation to obtain a mixture; b. after the mixture is prepared and molded and powder is removed, uniformly arranging the molded material in a chain grate by using a roller screen machine, and drying, curing and reinforcing the molded material in the chain grate by sequentially passing through an air blowing area, an air suction area and a preheating area; c. and then the formed material enters a rotary kiln for concentrated high-temperature roasting, vanadium-containing formed clinker is obtained after discharging, and the vanadium-containing formed clinker is crushed to the required granularity and then subjected to water leaching or acid leaching to obtain vanadium-containing leachate for subsequent vanadium precipitation.

Further, the vanadium-containing material in the step a is converter vanadium slag, vanadium-containing stone coal, vanadium-containing steel slag or vanadium-containing waste catalyst.

Further, the additive in the step a comprises a sodium additive or a calcification additive, wherein the sodium additive is sodium carbonate, sodium bicarbonate, sodium sulfate or sodium bisulfate; the calcification additive is limestone, calcium oxide or calcium sulfate.

Further, in the step a, the molar ratio of the additive to the vanadium is 0.5: 1-5: 1.

Further, in the step a, the time for mechanical activation is 10-120 min.

Further, in the step b, the molding size is 5-50 mm.

Further, in the step b, the thickness of the material is 50-300 mm.

Further, in the step b, the temperature of the air blowing zone is 200-300 ℃.

Further, in the step b, the curing time is 30-100 min.

Further, in the step c, the high-temperature roasting temperature is 820-1000 ℃, the high-temperature roasting time is 60-180 min, and the discharging temperature is 600-900 ℃.

The invention has the beneficial effects that: the method provided by the invention has the technical advantages of simple and easy process, low equipment requirement, convenience in operation, wide application range and low cost by roasting the vanadium-containing material by using the chain grate and the rotary kiln, and also effectively solves the technical problems of material adhesion, low conversion rate and leaching rate and high energy consumption in the material roasting process, and has the advantages of obvious technical advantages and wide market popularization prospect, and is particularly suitable for the roasting process of the vanadium-containing material.

Drawings

FIG. 1 is a schematic view of a processing apparatus utilized in the present invention.

Labeled as: the device comprises a vanadium-containing material inlet 1, a blowing area 2, an air draft area 3, a preheating area 4, a roasting clinker port 5, a circular cooler 6, a coal powder and air input port 7, a rotary kiln 8, a chain grate machine 9, a discharge port 10, a main air draft port 11, a chimney discharge port 12, a drying blower 13, a regenerative fan 14 and a cooling fan 15.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

The method for roasting vanadium-containing materials by using a chain grate and a rotary kiln as shown in figure 1 comprises the following steps: a. firstly, crushing a vanadium-containing material to a required granularity, then mixing the vanadium-containing material with an additive, and then carrying out mechanical activation to obtain a mixture; b. after the mixture is prepared and molded and powder is removed, uniformly arranging the molded material in a chain grate by using a roller screen machine, and drying, curing and reinforcing the molded material in the chain grate by sequentially passing through an air blowing area, an air suction area and a preheating area; c. and then the formed material enters a rotary kiln for concentrated high-temperature roasting, vanadium-containing formed clinker is obtained after discharging, and the vanadium-containing formed clinker is crushed to the required granularity and then subjected to water leaching or acid leaching to obtain vanadium-containing leachate for subsequent vanadium precipitation.

The core concept of the invention is that: firstly, preprocessing a vanadium-containing material, uniformly distributing the material in a grate 9 through a roller screen machine, drying and dehydrating the material, curing the material at a high temperature, then efficiently converting the material in a rotary kiln 8 to obtain clinker, and leaching the clinker with water or acid to obtain vanadium-containing leachate for subsequent vanadium precipitation. Due to successful innovation and breakthrough in the processing method, the effects of simple and easy process, wide application range and low cost are well realized, and the method also has very high social and economic benefits and wide market popularization prospect in the future. Generally, the vanadium-containing material and the additive in the step a have a particle size of less than 0.12mm, namely, the vanadium-containing material and the additive are preferably sieved by a 120-mesh sieve. And c, after the molding in the step b, preferably removing the adhered powder after the materials pass through a roller screen. In step c, the heating mode is preferably rolling type heating, namely the contact area of hot air and the material layer is wide, which is different from the radiation heat exchange of a common roasting furnace, especially a multi-hearth furnace. In the step c, the hot air in the high temperature area can be used for heating the vanadium-containing molding material of the chain grate 9 after passing through the vanadium-containing molding material, and the hot air in the final heating area can be used for the drying area, so that the comprehensive utilization of energy is realized, and the energy consumption is reduced.

In order to enlarge the acquisition range of vanadium-containing materials and improve the quality of corresponding products, the following scheme can be selected: the vanadium-containing material in the step a is converter vanadium slag, vanadium-containing stone coal, vanadium-containing steel slag or vanadium-containing waste catalyst.

In order to optimize the choice of additives, such a solution can be chosen: the additive in the step a comprises a sodium additive or a calcification additive, wherein the sodium additive is sodium carbonate, sodium bicarbonate, sodium sulfate or sodium bisulfate, and the sodium carbonate and the sodium bicarbonate are preferably selected; the calcification additive is limestone, calcium oxide or calcium sulfate, preferably calcium carbonate.

Meanwhile, in order to further optimize the product quality and further improve the production process, the following scheme can be selected and optimized: in the step a, the molar ratio of the additive to vanadium is 0.5: 1-5: 1; in the step a, the mechanical activation time is 10-120 min; in the step b, the molding size is 5-50 mm; in the step b, the thickness of the material is 50-300 mm; in the step b, the temperature of the blast area 2 is 200-300 ℃; in the step b, the curing time is 30-100 min; in the step c, the high-temperature roasting temperature is 820-1000 ℃, the high-temperature roasting time is 60-180 min, and the discharging temperature is 600-900 ℃.