Organic matter vanadium removal slurry treatment method

Abstract

The invention relates to the field of organic matter vanadium removal, and provides an organic matter vanadium removal slurry treatment method which comprises the following steps: S1, adding heated vanadium removal slurry into a TiCl4 solution for reduction reaction; s2, distilling the reacted TiCl4 solution in vacuum to respectively obtain TiCl4 and impurities; and S3, the impurities serve as vanadium removal slurry, the step S1 and the step S2 are repeated till the preset time is reached. According to the method, TiCl4 is separated out through distillation at a low temperature, TiCl4 recycling is achieved, the temperature is further increased, impurities such as FeCl3, VOCl3 and AlCl3 are separated out independently, residues obtained after separation are returned to the vanadium removal process to be continuously used, and therefore the consumption of an organic matter vanadium removal reagent is effectively reduced, and emission reduction of an organic matter vanadium removal source is achieved. The recovery rate of vanadium and titanium in the vanadium-removed slurry can be effectively improved, and the utilization rate of vanadium is improved.

Description

Technical Field

[0001] The invention relates to the field of vanadium removal from organic matter, and more specifically to a method for treating slurry for vanadium removal from organic matter. Background Art

[0002] Vanadium is an important strategic resource and is widely used in the fields of steel, nonferrous metallurgy, and chemical industry. Organic vanadium removal slurry contains a large amount of vanadium. How to efficiently extract and recycle this vanadium is an important technical challenge currently faced. Organic vanadium removal slurry has a complex composition and contains a variety of organic and inorganic substances, which makes it difficult to treat. Traditional treatment methods may have problems such as high energy consumption, low efficiency, and environmental pollution.

[0003] Titanium tetrachloride (TiCl4) is the basic raw material for the production of titanium metal and titanium dioxide, and is a key link in the realization of the full-process titanium industry chain. At present, TiCl4 is mainly produced by boiling chlorination and molten salt chlorination. Boiling chlorination has high requirements for raw material quality, usually (CaO+MgO) <1.5%, while molten salt chlorination has better adaptability to raw materials. Regardless of the chlorination technology, the vanadium impurities contained in the titanium raw material will be chlorinated during the chlorination process to form impurities such as VOCl3 and VCl4, which will enter TiCl4, and cannot meet the preparation needs of titanium metal and titanium dioxide. Chemical methods are required for separation and removal. The main vanadium removal processes in the industry include copper wire vanadium removal, H2S vanadium removal, aluminum powder vanadium removal, and organic vanadium removal. At present, intermittent operation and poor treatment environment of copper wire vanadium removal have been eliminated, and H2S is only applied in Toho Titanium Industry in Japan. Aluminum powder vanadium removal technology is mainly concentrated in TiCl4 production enterprises in the CIS countries and some enterprises in my country, while most TiCl4 production enterprises in Europe, the United States, Japan and my country use organic vanadium removal technology.

[0004] When removing vanadium from organic matter, the vanadium removal reagent is usually heated to hot TiCl4, and cracking and dehydrogenation occur under the action of TiCl4 to form activated carbon particles. There are active points on the surface of the activated carbon particles, which can reduce vanadium-containing impurities such as VOCl3 and VCl4 in the TiCl4 solution to high-boiling VOCl2, VCl3, etc., and separate TiCl4 by distillation. High-boiling vanadium impurities and carbon impurities will remain at the bottom of the distillation kettle, and the refined mud is discharged in a continuous or intermittent manner, thereby achieving the separation of high-boiling impurities and the continuous vanadium removal reaction. The discharged refined mud contains a large amount of TiCl4, which needs to be recycled. At present, filtration separation, distillation, back chlorination furnace, and fluidized bed are mainly used to achieve recycling. Organic vanadium removal is currently an important industrial method for separating vanadium impurities in TiCl4. The refined mud after vanadium removal is the main outlet for high-boiling carbon impurities. At present, it is mainly treated by slurry evaporation or back chlorination furnace. There are problems such as system circulation enrichment and low utilization rate of vanadium removal reagents, which is not conducive to energy saving and emission reduction of organic vanadium removal process. Summary of the invention

[0005] Based on the above purpose, the present invention proposes a method for treating organic matter vanadium removal slurry, comprising the following steps: S1. The heated vanadium removal slurry is added to the TiCl4 solution for reduction reaction; S2. distilling the TiCl4 solution after the reaction under vacuum to obtain TiCl4 and impurities respectively; S3. Repeat steps S1 and S2 with the impurities as vanadium removal slurry until a preset time is reached.

[0006] In some embodiments, in step S1, VOCl3 and VCl4 in the TiCl4 solution are reduced to VOCl2 and VCl3.

[0007] In some embodiments, the reduction reaction is carried out as follows: 4VOCl3+C=4VOCl2↓+CCl4↑; 4VCl4+C=4VCl3↓+CCl4↑.

[0008] In some embodiments, in step S2, the vacuum degree ranges from -20 to 0 kPa.

[0009] In some embodiments, in step S2, the temperature range of distillation separation of TiCl4 is 137°C to 300°C.

[0010] In some embodiments, in step S2, the temperature range of distilling and separating impurities is 400°C to 600°C.

[0011] In some embodiments, upon separation of impurities by distillation, VOCl2 and VCl3 decompose into VCl2, VCl4, VOCl, and VOCl3.

[0012] In some embodiments, the decomposition process is as follows: 2VOCl2=VOCl↑+VOCl3↑; 2VCl3=VCl2↓+VCl4↑.

[0013] In some embodiments, VCl 4 , VOCl and VOCl 3 are collected during the distillation process.

[0014] In some embodiments, VCl2 is present during the distillation process as an impurity.

[0015] The present invention has at least the following beneficial technical effects: The present invention provides a method for treating organic vanadium removal slurry, which comprises: S1. adding heated vanadium removal slurry into TiCl4 solution for reduction reaction; S2. distilling the TiCl4 solution after the reaction under vacuum to obtain TiCl4 and impurities respectively; S3. using the impurities as vanadium removal slurry and repeating steps S1 and S2 until a preset time is reached.

[0016] The present invention separates TiCl4 by distillation at a relatively low temperature, realizes the recycling and reuse of TiCl4, further raises the temperature to separate impurities such as FeCl3, VOCl3, AlCl3, etc., and the separated residue is returned to the vanadium removal process for continued use, thereby effectively reducing the consumption of organic vanadium removal reagents and realizing organic vanadium removal source reduction. The recovery rate of vanadium and titanium in vanadium removal slurry can be effectively improved, and the utilization rate of vanadium can be improved. The method is simple in process, easy to operate, easy to promote, and can effectively improve the recovery rate of vanadium and titanium and reduce energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 A flow chart of a method for treating an organic matter vanadium removal slurry according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0018] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0019] In addition, reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0020] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined as in the embodiments of this application.

[0021] The present invention provides a method for treating organic matter vanadium removal slurry, comprising the following steps: S1. The heated vanadium removal slurry is added to the TiCl4 solution for reduction reaction; S2. distilling the TiCl4 solution after the reaction under vacuum to obtain TiCl4 and impurities respectively; S3. Repeat steps S1 and S2 with the impurities as vanadium removal slurry until a preset time is reached.

[0022] The present invention separates TiCl4 by distillation at a relatively low temperature. At a relatively low temperature, the vapor pressure of TiCl4 is relatively high, and it is easier to distill TiCl4 from the mud, thereby efficiently separating TiCl4 and reducing the complexity of subsequent treatment. Low-temperature distillation helps to avoid chemical reactions occurring at high temperatures, thereby maintaining the chemical stability of TiCl4.

[0023] Then the temperature is further increased to separate impurities such as FeCl3, VOCl2, and VCl3. When the temperature is further increased, the vapor pressure of impurities such as VCl3 gradually increases and is effectively separated, further improving the purity of the product. By precisely controlling the temperature, different impurities can be separated one by one, improving the separation accuracy. Finally, the separated residue is used as a vanadium removal reagent to continue vanadium removal. The separated residue is rich in vanadium and can be used as a vanadium removal reagent in the vanadium removal process. This not only realizes the reuse of resources, but also reduces the demand for new vanadium removal reagents. The reuse of residues helps to reduce production costs and improve economic benefits.

[0024] In the process of treating organic vanadium removal slurry, vanadium removal slurry including VCl2 and C is selected as vanadium removal agent. It usually contains functional groups that can form stable complexes with vanadium ions. When organic matter contacts vanadium ions in the slurry, chemical reactions will occur between them to form insoluble vanadium-organic complexes. In the process of treating organic vanadium removal slurry, the slurry will first be evaporated and concentrated. The purpose of evaporation and concentration is to reduce the moisture content in the slurry and increase the concentration of organic matter and vanadium ions. This helps to accelerate the chemical reaction between organic matter and vanadium ions and prepare for the subsequent physical separation process. The slurry after evaporation and concentration will enter the vapor-solid separation stage. In this stage, the slurry will be heated to a certain temperature to evaporate volatile substances such as titanium tetrachloride contained therein. At the same time, the insoluble vanadium-organic complex will remain in the solid residue. Through vapor-solid separation technology (such as flash tank), titanium tetrachloride vapor and carbon-containing vanadium slag can be collected separately. The collected titanium tetrachloride vapor can be recycled and reused after condensation and purification. The carbon-vanadium-containing slag can be further refined and processed to recover the vanadium element.

[0025] Therefore, by utilizing the specific properties of organic matter, it can efficiently combine with vanadium ions, thereby achieving effective removal of vanadium. The vanadium content in the treated mud can be significantly reduced to an extremely low level, ensuring the purity of the product. The reduction in vanadium content helps to improve the overall quality of the product, making it more in line with high-standard application requirements. Pure products show better performance in subsequent processing, such as higher strength and better corrosion resistance.

[0026] In some embodiments, see Figure 1 In step S1, VOCl3 and VCl4 in the TiCl4 solution are reduced to VOCl2 and VCl3.

[0027] The VOCl2 and VCl3 produced during the reduction process still have high chemical activity and can be used to prepare other vanadium compounds, thus maximizing the utilization of resources and reducing resource waste. Through the reduction reaction, the effective conversion of VOCl3 and VCl4 is achieved, which reduces the demand for new raw materials, reduces production costs, and improves economic benefits.

[0028] In some embodiments, see Figure 1 , the reduction reaction process is as follows: 4VOCl3+C=4VOCl2↓+CCl4↑; 4VCl4+C=4VCl3↓+CCl4↑.

[0029] In some embodiments, see Figure 1 In step S2, the vacuum degree range is -20~0kPa.

[0030] The distillation separation can be carried out under vacuum to improve the separation efficiency of TiCl4 and impurities such as FeCl3, VOCl2, VCl3, etc. The optimal vacuum degree is -20~0kPa.

[0031] Under vacuum conditions, the boiling point of a substance will drop significantly. This is because as the pressure decreases, the interaction between molecules weakens, making it easier for molecules to change from a liquid state to a gas state. This reduction in boiling point helps to achieve distillation separation of substances at a lower temperature, thereby improving separation efficiency. A better vacuum degree can reduce heat loss during the distillation process, allowing heat to be more efficiently transferred to the FeCl3, VOCl2, and VCl3 to be distilled, accelerating their vaporization process. A vacuum environment helps to reduce the contact between the solution and oxygen in the air, thereby preventing VOCl3 and VCl4 from undergoing oxidation reactions during the distillation process and facilitating operation.

[0032] In some embodiments, see Figure 1 In step S2, the temperature range of distillation separation of TiCl4 is 137℃~300℃.

[0033] The temperature of distillation separation of TiCl4 is controlled above the boiling point of TiCl4 (137°C) and below the boiling point of FeCl3 impurities (315°C). The optimal temperature control is 137°C~300°C; In this temperature range, the vapor pressure of TiCl4 is moderate, which is conducive to its efficient evaporation from the solution, ensuring the stability and efficiency of the distillation process, so that TiCl4 can be effectively separated from other impurities. By precisely controlling the distillation temperature, energy waste caused by too high or too low temperature can be avoided, and the distillation process can achieve the best separation effect with the least energy consumption.

[0034] In some embodiments, see Figure 1 In step S2, the temperature range for distilling and separating impurities is 400°C to 600°C.

[0035] The separation temperature of impurities such as iron and vanadium is above the boiling point of FeCl3 (315°C), and the optimal temperature control is 400°C~600°C; At high temperatures, impurities such as iron and vanadium react to generate high-boiling chlorides. These high-boiling chlorides are easier to separate from the remaining solution during the distillation process, thereby improving separation efficiency. Full reaction at high temperatures can ensure that impurities are more thoroughly converted and reduce the amount of residues in the main substance. This helps to improve the purity and quality of the product. At the same time, since different impurities have different reaction temperatures, it is easier to achieve the conversion and separation of multiple impurities at high temperatures, thereby meeting different production needs.

[0036] In some embodiments, see Figure 1 During the distillation to separate impurities, VOCl2 and VCl3 decompose into VCl2, VCl4, VOCl and VOCl3.

[0037] At the relatively high temperature, vanadium-containing impurities such as VOCl2 and VCl3 react to generate low-boiling-point VCl4, VOCl and VOCl3, which enter the high-boiling-point impurity collector, while the high-boiling-point VCl2 is contained in the residual carbon.

[0038] In some embodiments, see Figure 1 , the decomposition process is as follows: 2VOCl2=VOCl↑+VOCl3↑; 2VCl3=VCl2↓+VCl4↑.

[0039] The residue after high-temperature distillation can be used as a vanadium removal reagent to react with vanadium impurities such as VOCl3 and VCl4 in TiCl4, thereby realizing the reuse of carbon impurities in the vanadium removal slurry.

[0040] In some embodiments, see Figure 1 , VCl4, VOCl and VOCl3 were collected during the distillation process.

[0041] The impurity collection devices for separating TiCl4 and FeCl3, VOCl2, VCl3, etc. by distillation of the vanadium removal slurry are independent of each other, so as to realize the separation of impurities such as TiCl4 and FeCl3.

[0042] Independent impurity collection devices can be precisely controlled and processed for each impurity. According to the different boiling points of TiCl4 and FeCl3, the operating parameters of the collection device are adjusted to achieve the best separation effect. Independent devices can avoid mutual interference between different impurities, helping to ensure that each impurity can be effectively collected and processed, thereby improving the overall separation efficiency.

[0043] In some embodiments, see Figure 1 , VCl2 exists as an impurity during the distillation process.

[0044] The VCl2 high-boiling point impurities remaining from the high-temperature distillation can also undergo reversible reactions with VOCl3 and VCl4 as shown in Formula 1 and Formula 2, thereby having a vanadium removal effect.

[0045] By using VCl2 as a new vanadium removal slurry, the vanadium removal efficiency can be significantly improved and the residual amount of vanadium in the target substance can be reduced. As a component of the vanadium removal slurry, VCl2 can be effectively recovered and reused after the reaction. This helps save production costs while reducing the demand for new resources. An efficient vanadium removal process can reduce waste generation and emissions. By recycling and reusing VCl2, pollution and damage to the environment can be reduced, which is in line with the concept of green production and sustainable development.

[0046] The use of VCl2 as vanadium removal slurry can be adjusted according to different production requirements and process conditions. The concentration of VCl2, reaction time, temperature and other parameters can be changed to meet the treatment requirements of different vanadium-containing mixtures.

[0047] Since the residue after separation of the vanadium removal sludge is used again as a vanadium removal reagent, the consumption of organic vanadium removal reagents is effectively reduced, and source reduction of organic vanadium removal is achieved, which has a good preliminary stage for promotion and application.

[0048] Embodiment 1: Take 1000g of organic vanadium removal slurry in a distillation furnace, control the distillation temperature and vacuum degree to 200℃ and -10kPa respectively for distillation, remove the distillation product collection device after the distillation is completed, and obtain 915g of distillation product. Then, reconnect a new distillation collection device, continue to control the distillation temperature and vacuum degree to 500℃ and -10kPa respectively for distillation, remove the distillation product collection device after the distillation is completed, and obtain 42g of high-temperature distillation product. Add the high-temperature distillation residue and crude TiCl4 at 0.2kg / kgVOCl3. After removing vanadium at 137℃ for 30min, the VOCl3 content in crude TiCl4 can be reduced from 0.15% to less than 0.0001%.

[0049] In this embodiment, the VOCl3 content in the crude TiCl4 is significantly reduced through an effective vanadium removal process, thereby improving the purity of the product. High-purity TiCl4 can show better performance and stability in subsequent production and applications. High-quality products can meet more stringent market demands and improve the market competitiveness of enterprises. High-quality TiCl4 can be sold as raw materials or semi-finished products, bringing higher economic benefits to enterprises, simplifying production processes, and reducing unnecessary steps and energy consumption.

[0050] Embodiment 2: Take 2000g of organic vanadium removal slurry in a distillation furnace, control the distillation temperature and vacuum degree to 250℃ and -5kPa respectively for distillation, remove the distillation product collection device after the distillation is completed, and obtain 921g of distillation product. Then, reconnect a new distillation collection device, continue to control the distillation temperature and vacuum degree to 600℃ and -20kPa respectively for distillation, remove the distillation product collection device after the distillation is completed, and obtain 46g of high-temperature distillation product. Add the high-temperature distillation residue and crude TiCl4 at 0.12kg / kgVOCl3, and after removing vanadium at 137℃ for 30min, the VOCl3 content in crude TiCl4 can be reduced from 0.15% to 0.0003%.

[0051] This embodiment significantly reduces the content of impurities such as VOCl3 in crude TiCl4, avoids cumbersome separation steps, simplifies the production process, and improves resource utilization by recovering and reusing effective components in high-temperature distillation residues.

[0052] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0053] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0054] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for treating organic matter vanadium removal slurry, characterized in that: The following steps are involved: S1. The heated vanadium removal slurry is added to the TiCl4 solution for reduction reaction; S2. distilling the TiCl4 solution after the reaction under vacuum to obtain TiCl4 and impurities respectively; S3. Repeat steps S1 and S2 with the impurities as vanadium removal slurry until a preset time is reached.

2. The method for treating organic matter vanadium removal slurry according to claim 1, characterized in that: In step S1, VOCl3 and VCl4 in the TiCl4 solution are reduced to VOCl2 and VCl3.

3. The method for treating organic matter vanadium removal slurry according to claim 2, characterized in that: The process of reduction reaction is as follows: 4VOCl3+C=4VOCl2↓+CCl4↑; 4VCl4+C=4VCl3↓+CCl4↑.

4. The method for treating organic matter vanadium removal slurry according to claim 1, characterized in that: In step S2, the vacuum degree ranges from -20 to 0 kPa.

5. The method for treating organic matter vanadium removal slurry according to claim 1, characterized in that: In step S2, the temperature range of distillation separation of TiCl4 is 137°C to 300°C.

6. The method for treating organic matter vanadium removal slurry according to claim 1, characterized in that: In step S2, the temperature range for distilling and separating impurities is 400°C to 600°C.

7. The method for treating organic matter vanadium removal slurry according to claim 6, characterized in that: During the distillation to separate the impurities, VOCl2 and VCl3 decompose into VCl2, VCl4, VOCl and VOCl3.

8. The method for treating organic matter vanadium removal slurry according to claim 7, characterized in that: The decomposition process is as follows: 2VOCl2=VOCl↑+VOCl3↑; 2VCl3=VCl2↓+VCl4↑.

9. The method for treating organic matter vanadium removal slurry according to claim 6, characterized in that: VCl4, VOCl and VOCl3 were collected during the distillation.

10. The method for treating organic matter vanadium removal slurry according to claim 6, characterized in that: During the distillation process, VCl2 exists as an impurity.

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