Method for producing vanadium slag by refining vanadium removal slurry and slurry evaporation furnace

Abstract

The invention discloses a method for producing vanadium slag by refining vanadium removal slurry in titanium tetrachloride production and a pulp evaporation furnace, comprising an evaporation furnace body, a discharge pipe, the discharge pipe is arranged at the lower end of the evaporation furnace body; a gas distribution plate, the gas distribution plate is movably installed at the lower end of the discharge pipe; a discharge valve, the discharge valve is installed on the discharge pipe and is located between the gas distribution plate and the evaporation furnace body; the gas distribution plate has a plurality of vents connected to the discharge pipe. After the vanadium removal slurry is evaporated to dryness, air is introduced while hot for reaction, and then the vanadium slag is discharged. The method for producing vanadium slag by refining vanadium removal slurry and the pulp evaporation furnace provided by the present invention, by introducing air into the pulp evaporation furnace, oxygen in the air is subjected to an oxidation-reduction reaction with the evaporated vanadium removal slurry, the whole reaction is an exothermic reaction, and the reaction temperature in the pulp evaporation furnace can be effectively maintained, so that the reaction temperature is maintained at 300-600°C, thereby obtaining vanadium slag with a low chlorine content.

Description

Technical Field

[0001] The invention relates to the technical field of titanium tetrachloride production, and in particular to a method for producing vanadium slag by refining vanadium-removing slurry in titanium tetrachloride production and a slurry evaporation furnace. Background Art

[0002] The main methods for large-scale production of TiCl4 are boiling chlorination and molten salt chlorination. In the chlorination process of these two processes, the easily chlorinated V2O5 in the raw materials will also be chlorinated and enter the (crude) titanium tetrachloride, with a content of about 0.10% to 0.25%, in the form of VOCl3. In industrial production, chemical methods are required to remove VOCl3 impurities in crude TiCl4, that is, using a specific reducing agent to convert the vanadium compound VOCl3 impurity that is infinitely miscible with TiCl4 into a vanadium compound (VCl4, VOCl2, etc.) precipitate, and then obtain refined TiCl4 with extremely low VOCl3 content through distillation or rectification. This process is called refined vanadium removal. Vanadium removal slurry is a titanium tetrachloride mixture containing solids after the reaction of low-valent vanadium compounds and vanadium removal products.

[0003] For vanadium removal slurry, the existing technology usually uses spray condensation to separate organic vanadium removal residue from vanadium removal slurry, and uses slurry evaporation to separate aluminum powder vanadium removal residue from vanadium removal slurry. However, the spray condensation method does not achieve resource recycling, and the vanadium-containing tailings are a hazardous waste that pollutes the environment; the vanadium slag obtained by slurry evaporation has a high chlorine content and cannot be used in downstream production. How to treat vanadium removal slurry in an environmentally friendly manner has become a technical problem that needs to be solved urgently by those skilled in the art.

[0004] Based on this, the existing technology still needs to be improved. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for producing vanadium slag by refining vanadium removal slurry and a slurry evaporation furnace, so as to solve the environmental friendliness problem in the prior art when treating vanadium removal slurry.

[0006] According to some embodiments of the present invention, a method for producing vanadium slag by refining vanadium removal slurry is provided, wherein the vanadium removal slurry is evaporated to dryness, air is introduced while hot to react, and then the vanadium slag is discharged.

[0007] In some embodiments, the method includes:

[0008] The vanadium removal slurry is evaporated to dryness in a slurry evaporation furnace to obtain refined tailings;

[0009] Introducing air into the slurry evaporation furnace while maintaining stirring to allow the air to fully react with the refined tailings;

[0010] Stop stirring and discharge the vanadium slag that has completed the reaction in the slurry evaporation furnace;

[0011] Wherein, the chlorine content of the vanadium slag is not more than 0.1% by mass ratio.

[0012] In some embodiments, during the air introduction process, the temperature in the slurry evaporation furnace is maintained at 300-600°C.

[0013] In some embodiments, the air flow rate is 80Nm 3 / h~120Nm 3 / h;

[0014] The pressure of the incoming air is 5kpa~10kpa.

[0015] In some embodiments, the reaction time for the air to fully react with the refined tailings is 30 to 60 minutes.

[0016] In some embodiments, air is introduced from the bottom of the slurry evaporation furnace.

[0017] In some embodiments, a discharge pipe is provided at the bottom of the slurry evaporation furnace, and a discharge valve is provided at a position of the discharge pipe close to the bottom of the evaporation furnace, and air is introduced from below the discharge valve.

[0018] In some embodiments, after stopping stirring, the discharge valve at the bottom of the slurry evaporation furnace is first closed, and then the air supply is stopped.

[0019] According to some embodiments of the present invention, a slurry evaporation furnace for refining vanadium removal slurry to produce vanadium slag is also proposed, comprising:

[0020] Evaporation furnace body,

[0021] A discharge pipe, the discharge pipe being arranged at the lower end of the evaporation furnace body;

[0022] A gas distribution plate, the gas distribution plate being movably mounted at the lower end of the discharge pipe;

[0023] A discharge valve, which is installed on the discharge pipe (furnace bottom pipe) and is located between the gas distribution plate and the evaporation furnace body;

[0024] Furthermore, the gas distribution plate has a plurality of vent holes connected to the discharge pipe.

[0025] In some embodiments, a gas delivery pipeline is further included, wherein the gas delivery pipeline is connected to the gas distribution plate, and a gas delivery valve and a gas pressure regulating device are provided on the gas delivery pipeline.

[0026] In some embodiments, the gas distribution plate includes a distribution plate body, a connection portion and a rotating mechanism, wherein the connection portion is formed by extending from one side of the distribution plate body, and the connection portion is mounted on the wall of the discharge pipe through the rotating mechanism;

[0027] Furthermore, when the rotating mechanism is located at the first position, the upper surface of the distribution plate body faces the lower end surface of the discharge pipe;

[0028] When the rotating mechanism is located at the second position, the upper surface of the distribution plate body is away from the lower end surface of the discharge pipe.

[0029] In some embodiments, the rotation axis of the rotating mechanism is parallel to the length direction of the discharge pipe.

[0030] In some embodiments, the rotation axis of the rotating mechanism is perpendicular to the length direction of the discharge pipe, so that the first side of the distribution plate body is connected to the rotation axis through a connecting part, and the opposite side away from the first side of the distribution plate body rotates around the rotation axis. When the plane where the distribution plate body is located and the rotation axis are in the same vertical plane, the outlet at the lower end of the discharge pipe is opened and the discharge operation can be performed. When the plane where the distribution plate body is located is a horizontal plane, the upper surface of the distribution plate body is attached to the lower end of the discharge pipe, and the operation of introducing air can be realized.

[0031] By adopting the above technical solution, the present invention has at least the following beneficial effects:

[0032] The method for producing vanadium slag from refined vanadium removal slurry and the pulp evaporation furnace provided by the present invention, by introducing air into the pulp evaporation furnace, oxygen in the air and evaporated vanadium removal slurry undergo oxidation-reduction reaction, the whole reaction is an exothermic reaction, and the reaction temperature in the pulp evaporation furnace can be effectively maintained at 300-600°C, thereby obtaining vanadium slag with a low chlorine content. The metal ions and chloride ions in the refined tailings exist in the form of chlorine-oxygen metal compounds, which are an unstable form, and form stable oxides under oxygen and high temperature conditions. At the same time, the heat required by the system is generated by the combustion of carbon and oxygen, and production can be completed without additional heating. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A schematic structural diagram of a slurry evaporation furnace for refining vanadium-removing slurry to produce vanadium slag disclosed in some embodiments of the present invention is shown. DETAILED DESCRIPTION

[0035] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0036] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0037] Some embodiments of the present invention disclose a method for producing vanadium slag by refining vanadium removal slurry. After the vanadium removal slurry is evaporated to dryness, air is introduced into the slurry while it is hot to react, and then the vanadium slag is discharged.

[0038] Some embodiments of the present invention disclose a method for producing vanadium slag by refining vanadium-removing slurry, comprising:

[0039] The vanadium removal slurry is evaporated to dryness in a slurry evaporation furnace to obtain refined tailings;

[0040] Air is introduced into the slurry evaporation furnace while stirring to allow the air to fully react with the refined tailings; during the air introduction process, the temperature in the slurry evaporation furnace is maintained at 300-600°C, and the air flow rate is 80Nm 3 / h~120Nm 3 / h; 100Nm can be added per hour according to 1t of slag 3 / h ratio is matched, depending on the amount of refined tailings.

[0041] The pressure of the air introduced is 5kpa~10kpa;

[0042] The reaction time for the air to fully react with the refined tailings is 30 to 60 minutes.

[0043] Stop stirring and discharge the vanadium slag that has completed the reaction in the slurry evaporation furnace;

[0044] Wherein, the chlorine content of the vanadium slag is not more than 0.1% by mass ratio.

[0045] The method for producing vanadium slag from refined vanadium removal slurry provided in the above embodiment is to introduce air into the slurry evaporation furnace so that oxygen in the air and the evaporated vanadium removal slurry undergo oxidation-reduction reaction. The entire reaction is an exothermic reaction, which can effectively maintain the reaction temperature in the slurry evaporation furnace at 300-600°C to obtain vanadium slag without chlorine. The refined slurry is passed through the slurry evaporation furnace to obtain vanadium slag, which protects the environment while realizing the recycling of vanadium resources. This technology can be promoted and applied to the titanium dioxide chloride and sponge titanium industries. After adopting this technology, the refined slurry is passed through the slurry evaporation furnace to obtain vanadium slag, with a vanadium content of 25-30%, a profit of 20,000 yuan per ton of vanadium slag, and 400 tons of vanadium slag are produced per year, which can generate benefits of 8 million yuan / a, where a means year.

[0046] Some embodiments of the present invention disclose a method for producing vanadium slag by refining vanadium-removing slurry. Based on the above embodiments, in order to facilitate the introduction of air and the sufficient mixing reaction with the materials in the evaporation furnace, air is preferably introduced from the bottom of the slurry evaporation furnace.

[0047] In some specific implementations, such as Figure 1 As shown, a discharge pipe 2 is provided at the bottom of the slurry evaporation furnace, and a discharge valve 4 is provided at a position of the discharge pipe 2 near the bottom of the evaporation furnace, and air is introduced from below the discharge valve 4. When in use, after stopping stirring, the discharge valve 4 at the bottom of the slurry evaporation furnace is first closed, and then the introduction of air is stopped.

[0048] Some embodiments of the present invention also disclose a slurry evaporation furnace for refining vanadium removal slurry to produce vanadium slag, which can be used for the above-mentioned vanadium slag production, and a movable gas distribution plate 3 is added below the valve at the bottom of the slurry evaporation furnace. After the slurry evaporation furnace confirms that the slurry is evaporated, the gas distribution pipe is opened to let air into the slurry evaporation furnace, so that the air reacts with the refined tailings in the slurry evaporation furnace, and finally obtains chlorine-free vanadium slag.

[0049] The slurry evaporation furnace may include: an evaporation furnace body 1, a discharge pipe 2, the discharge pipe 2 being arranged at the lower end of the evaporation furnace body 1; a gas distribution plate 3, the gas distribution plate 3 being movably installed at the lower end of the discharge pipe 2; a discharge valve 4, the discharge valve 4 being installed on the discharge pipe 2 and located between the gas distribution plate 3 and the evaporation furnace body 1; and the gas distribution plate 3 has a plurality of vents connected to the discharge pipe 2.

[0050] When in use, air is delivered to the evaporator body 1 through the vent holes on the gas distribution plate 3 to achieve the reaction between the air and the material in the evaporator. The gas distribution plate 3 is arranged below the discharge valve 4. After evaporation, ventilation is first performed to maintain a predetermined pressure, and then the discharge valve 4 is opened. Due to the existence of air pressure, the material can be prevented from falling from the discharge pipe 2. The material in the evaporator body 1 is blown upward under the action of the air pressure, and mixed under the stirring action of the stirring paddle. The material at the edge of the evaporator body 1 moves downward under the action of gravity, so that the solid material in the evaporator is fully moved, and the reaction speed between the solid material in the evaporator body 1 and the input air is accelerated.

[0051] like Figure 1 As shown, some embodiments of the present invention also disclose a slurry evaporation furnace for refining vanadium removal slurry to produce vanadium slag, which also includes a gas delivery pipeline, the gas delivery pipeline is connected to the gas distribution plate 3, and the gas delivery pipeline is provided with a gas delivery valve 5 and a gas pressure regulating device. The pressure regulating device can be appropriately adjusted according to the amount of material in the evaporation furnace body 1, and the input air speed can be adjusted to ensure the smooth completion of the reaction.

[0052] Some embodiments of the present invention also disclose a slurry evaporation furnace for refining vanadium-removing slurry to produce vanadium slag. On the basis of the above embodiments, the gas distribution plate 3 includes a distribution plate body, a connecting portion and a rotating mechanism, wherein the connecting portion is formed by extending from one side of the distribution plate body, and the connecting portion is installed on the wall of the discharge pipe 2 through the rotating mechanism; and when the rotating mechanism is in a first position, the upper surface of the distribution plate body faces the lower end surface of the discharge pipe 2; when the rotating mechanism is in a second position, the upper surface of the distribution plate body is away from the lower end surface of the discharge pipe 2.

[0053] Some embodiments of the present invention further disclose a slurry evaporation furnace for refining vanadium removal slurry to produce vanadium slag, and on the basis of the above embodiments, the rotation axis of the rotating mechanism is parallel to the length direction of the discharge pipe 2. In some other embodiments, the rotation axis of the rotating mechanism is perpendicular to the length direction of the discharge pipe 2, so that the first side of the distribution plate body is connected to the rotation axis through the connection part, and the opposite side away from the first side of the distribution plate body rotates around the rotation axis, when the plane where the distribution plate body is located and the rotation axis are located in the same vertical plane, the outlet at the lower end of the discharge pipe 2 is opened, and the discharge operation can be performed, and when the plane where the distribution plate body is located is a horizontal plane, the upper surface of the distribution plate body is attached to the lower end of the discharge pipe 2, and the operation of introducing air can be realized.

[0054] Some embodiments of the present invention disclose a method for producing vanadium slag by refining vanadium removal slurry, the steps of which are:

[0055] A. Make sure that the vanadium removal slurry in the slurry evaporation furnace has been evaporated;

[0056] B. Turn the gas distribution plate to the bottom valve of the slurry evaporation furnace and open the bottom valve of the slurry evaporation furnace;

[0057] C. Open the valve of the gas distribution plate to let air into the slurry evaporation furnace;

[0058] C. Keep the agitator stirring for 30min to 60min to allow the air to fully react with the refined tailings;

[0059] D. Stop stirring, close the bottom valve of the slurry evaporation furnace, and turn the gas distribution plate to the preparation position.

[0060] E. Transfer the slag tray to the bottom of the slurry evaporation furnace, open the valve at the bottom of the slurry evaporation furnace, and start stirring to discharge the vanadium slag.

[0061] This embodiment has a simple process, small equipment investment, and low energy consumption, and effectively reduces the chlorine content in the vanadium slag. The chlorine content in the obtained vanadium slag is ≤0.1%, which meets the needs of downstream vanadium product manufacturers.

[0062] Example 1

[0063] A method for producing vanadium slag by refining vanadium-removing slurry from organic matter, the main equipment of which includes: a slurry evaporation furnace, a gas distribution plate, and a slag pan. Follow the steps below:

[0064] 1. The post confirms that the vanadium removal slurry in the slurry evaporation furnace has been evaporated to dryness (the weight of one furnace is 1t, TV is 15%, C is 25%, TTi is 25%, and Cl is 35%);

[0065] 2. Move the gas distribution plate φ250mm to the bottom valve of the slurry evaporation furnace and open the bottom valve of the slurry evaporation furnace;

[0066] 3. Open the DN30mm valve on the gas distribution plate and distribute the air at 1500m 3 / h into the slurry evaporation furnace;

[0067] 4. Maintain the stirring speed of the stirrer at 4r / min, and heat the slurry evaporation furnace to maintain the temperature inside the furnace at 400℃ to allow the air to fully react with the refined tailings;

[0068] 5. After 60 minutes of reaction, turn off the heating system of the slurry evaporation furnace and set the air at 1000m 3 / h into the slurry evaporation furnace to reduce the temperature inside the furnace.

[0069] 6. When the temperature in the furnace drops to 200℃, stop stirring, close the bottom valve of the slurry evaporation furnace, and turn the gas distribution plate to the preparation position.

[0070] 7. Transfer the 1 t slag pan to the bottom of the slurry evaporation furnace, open the valve at the bottom of the slurry evaporation furnace, start stirring and discharge 500 kg of vanadium slag.

[0071] After inspection, the TV content of the obtained vanadium slag was 30% and the chlorine content was 0.08%.

[0072] Example 2

[0073] A method for producing vanadium slag from aluminum powder refining vanadium removal slurry, the main equipment of which includes: slurry evaporation furnace, gas distribution plate, slag pan. Follow the steps below:

[0074] 1. The post confirms that the vanadium removal slurry in the slurry evaporation furnace has been evaporated to dryness (the weight of one furnace is 800t, TV is 5%, Al is 30%, TTi is 24%, Cl is 30%, and the others are 11%);

[0075] 2. Move the gas distribution plate φ250mm to the bottom valve of the slurry evaporation furnace and open the bottom valve of the slurry evaporation furnace;

[0076] 3. Open the DN30mm valve on the gas distribution plate and distribute the air at 1000m 3 / h into the slurry evaporation furnace;

[0077] 4. Maintain the stirring speed of the stirrer at 5r / min, and heat the slurry evaporation furnace to maintain the temperature inside the furnace at 450℃ to allow the air to fully react with the refined tailings;

[0078] 5. After 90 minutes of reaction, turn off the heating system of the slurry evaporation furnace and ventilate the air at 800m 3 / h into the slurry evaporation furnace to reduce the temperature inside the furnace.

[0079] 6. When the temperature in the furnace drops to 200℃, stop stirring, close the bottom valve of the slurry evaporation furnace, and turn the gas distribution plate to the preparation position.

[0080] 7. Transfer the 1 t slag tray to the bottom of the slurry evaporation furnace, open the valve at the bottom of the slurry evaporation furnace, start stirring and discharge 520 kg of vanadium slag.

[0081] After inspection, the TV content of the obtained vanadium slag was 13.2%, and the chlorine content was 0.06%.

[0082] It should be particularly pointed out that the various components or steps in the above-mentioned embodiments can be cross-linked, replaced, added, or deleted with each other. Therefore, the combinations formed by these reasonable arrangements and combinations should also fall within the scope of protection of the present invention, and the scope of protection of the present invention should not be limited to the embodiments.

[0083] The above are exemplary embodiments disclosed in the present invention. The order disclosed in the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. However, it should be noted that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope (including claims) disclosed in the embodiments of the present invention is limited to these examples. Various changes and modifications may be made without departing from the scope defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

[0084] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for producing vanadium slag by refining vanadium removal slurry, characterized in that: After the vanadium removal slurry is evaporated to dryness, air is introduced while hot to react, and then the vanadium slag is discharged, including: The vanadium removal slurry is evaporated to dryness in a slurry evaporation furnace to obtain refined tailings; Introducing air into the slurry evaporation furnace while maintaining stirring to allow the air to fully react with the refined tailings; Stop stirring and discharge the vanadium slag that has completed the reaction in the slurry evaporation furnace; Wherein, the chlorine content in the vanadium slag is not more than 0.1% by mass ratio. During the air introduction process, the temperature in the slurry evaporation furnace is maintained at 400~600℃. The air flow rate is 80Nm 3 / h~120Nm 3 / h; The pressure of the air introduced is 5kpa~10kpa; A discharge pipe is provided at the bottom of the slurry evaporation furnace, and a discharge valve is provided at a position of the discharge pipe close to the bottom of the evaporation furnace, and air is introduced from below the discharge valve; The slurry evaporation furnace comprises: Evaporation furnace body, A discharge pipe, the discharge pipe being arranged at the lower end of the evaporation furnace body; A gas distribution plate, the gas distribution plate being movably mounted at the lower end of the discharge pipe; A discharge valve, which is installed on the discharge pipe and is located between the gas distribution plate and the evaporation furnace body; Furthermore, the gas distribution plate has a plurality of vent holes connected to the discharge pipe; Air is introduced from the bottom of the slurry evaporation furnace.

2. The method for producing vanadium slag by refining vanadium-removing slurry according to claim 1, characterized in that: The reaction time for the air to fully react with the refined tailings is 30 to 60 minutes.

3. The method for producing vanadium slag by refining vanadium-removing slurry according to claim 1, characterized in that: After stopping stirring, first close the discharge valve at the bottom of the slurry evaporation furnace, and then stop introducing air.

4. The method for producing vanadium slag by refining vanadium-removing slurry according to claim 1, characterized in that: It also includes a gas delivery pipeline, which is connected to the gas distribution plate, and a gas delivery valve and a gas pressure regulating device are arranged on the gas delivery pipeline.

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