Recycling method of distillation kettle residual liquid in titanium tetrachloride refining process

Abstract

The invention discloses a method for recycling residual liquid of a distillation kettle in a titanium tetrachloride refining process. The method comprises the following steps: (1) weighing the residual liquid: weighing the residual liquid of the distillation kettle in the TiCl4 refining process according to a set proportion as a binder; (2) raw material mixing: uniformly spraying a binder into the micro-fine particle titanium-rich material, and uniformly mixing the binder and the micro-fine particle titanium-rich material; (3) granulating: putting the uniformly mixed raw materials into a granulating machine, and granulating; and (4) drying and curing: drying and curing the granulation product to obtain the granulation product of the titanium-rich material. According to the method, the residual liquid of the distillation kettle in the TiCl4 refining process is used as a binder, the residual liquid contains TiCl4, AlCl3 and FeCl3, the residual liquid is returned to the fine-grain titanium-rich material granulation process, TiCl4 in the residual liquid is recycled, the particle size of the fine-grain titanium-rich material is increased, a granulation product with the particle size being 100-1000 microns and the proportion being 90% or above is obtained, and the granulation product can be directly applied to a boiling chlorination process.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium chemical industry and relates to a method for recycling residual liquid from a distillation kettle in a titanium tetrachloride refining process. Background Art

[0002] TiCl 4 It is an important intermediate raw material for the production of titanium sponge and titanium dioxide chloride by the chlorination process. Its production process includes boiling chlorination and molten salt chlorination. Among them, the boiling chlorination process has simple production equipment, large titanium tetrachloride output, and low three waste emissions. It is the mainstream process of my country's chlorination process. Titanium-rich materials (high titanium slag, artificial rutile) are subjected to boiling chlorination process to obtain crude TiCl 4 , which is mixed with impurities such as Al, V, and Fe. Table 1 shows the crude TiCl 4 Main chemical composition. To further improve TiCl 4 Purity, subsequent distillation, rectification, vanadium removal and refining steps are required to obtain refined TiCl 4 . Crude TiCl 4 During the distillation and rectification process, about 15% of the still residue will be produced, of which TiCl 4 The content is as high as 85% and needs to be recycled.

[0003] The traditional method of recovering the residual liquid from the distillation kettle is to return it to the refining process and repeat the processing and separation. However, this method causes the concentration of impurities in the system to increase continuously, and the process parameters need to be adjusted repeatedly during the refining process. 4 The study on hydrolysis recovery of distillation kettle residues proposed to use hydrolysis to remove impurities in distillation kettle residues and recover TiCl 4 At the same time, it reduces the processing load of the refining process. However, the hydrolysis process is complicated and difficult to apply in actual industry.

[0004] Table 1 Crude TiCl 4 Main chemical components

[0005] chemical composition <![CDATA[TiCl 4 ]]> <![CDATA[SiCl 4 ]]> Fe Al Fe V Content / wt% ≥98 0.1～0.6 0～1 0.01～0.1 0.01～0.04 0.01～0.03

[0006] TiCl 4 The main raw materials are titanium-rich materials (high-titanium slag, artificial rutile). my country's titanium resources are mainly stored in ilmenite, which needs to be prepared by fine grinding, acid leaching or electric furnace smelting. Therefore, the domestic production of titanium-rich materials generally has the problem of fine particle size and cannot be used in boiling chlorination process.

[0007] Based on this, the present invention proposes a method for recycling the residual liquid from the distillation kettle in the titanium tetrachloride refining process, and applies the residual liquid from the rear end of the boiling chlorination process to the front end raw material problem, thereby achieving full utilization of titanium resources. Summary of the invention

[0008] For efficient recycling of TiCl 4 The present invention aims to provide a method for recycling the residual liquid from the distillation kettle of the titanium tetrachloride refining process, so that the residual liquid is returned to the granulation process of the fine-grained titanium-rich material, and the TiCl 4 And the particle size of fine titanium-rich materials can be increased and applied to boiling chlorination process.

[0009] In order to achieve the above object, the present invention provides the following technical solutions:

[0010] The present invention discloses a method for recycling residual liquid from a distillation kettle in a titanium tetrachloride refining process, comprising the following steps:

[0011] (1) Weigh the residual liquid: weigh TiCl according to the set ratio 4 The residual liquid from the distillation kettle during the refining process is used as a binder;

[0012] (2) Raw material mixing: Spray the binder evenly into the fine titanium-rich material and mix well;

[0013] (3) Granulation: placing the mixed raw materials in a granulator for granulation;

[0014] (4) Drying and solidification: Drying and solidifying the granulated product to obtain a granulated product of titanium-rich material.

[0015] The fine-grained titanium-rich material in the present invention is high-titanium slag or artificial rutile with a particle size less than 100 μm after chemical treatment.

[0016] In step (1), TiCl 4 The chemical composition of the distillation residue in the refining process is:

[0017] TiCl 4 ≥85wt%;

[0018] AlCl 3 3-5wt%;

[0019] FeCl 3 0~1wt%.

[0020] In step (1), TiCl 4 The amount of residual liquid in the distillation kettle during the refining process is 2-8wt% of the amount of fine-grained titanium-rich material.

[0021] In step (2), the fine titanium-rich material and the residual liquid are mixed evenly.

[0022] In step (3), the granulation method of the fine titanium-rich material includes any one of a fluidized bed granulation method, a disc granulation method, a V-type mixer granulation method and a high-speed stirring granulation method.

[0023] In step (4), the particle size of the granulated product is 100 μm to 1000 μm, accounting for more than 90%, and the composition and particle strength meet the requirements of boiling chlorination.

[0024] The present invention adopts TiCl 4 The residual liquid from the distillation kettle during the refining process is used as a binder. The residual liquid contains TiCl 4 、AlCl 3 、FeCl 3 , returning to the fine titanium-rich material granulation process, not only recovering the TiCl 4 , and the particle size of the fine-grained titanium-rich material is increased, and the granulation product with a particle size of 100μm to 1000μm accounting for more than 90% is obtained, which can be directly applied to the boiling chlorination process. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] The present invention provides a crude TiCl 4 The method for recycling the residual liquid with high boiling point impurities collected during the refining process is to use crude TiCl 4 The high boiling point impurity residual liquid collected during the refining process is the binder solution. The prepared binder solution is sprayed on the fine titanium-rich material particles less than 100μm and mixed evenly. The mixed material is granulated, and the product particles obtained by granulation are dried in a fluidized bed. The cold strength and hot strength of the particles with a particle size distribution between 100 and 1000μm are measured.

[0027] In the present invention, the cold strength and hot strength of the granulated product are tested. The heat treatment method of the product particles is carried out in a muffle furnace by a coke burying method. 200g of dry granular products with a particle size distribution of 100-1000μm are weighed each time, placed in a Φ10×13cm graphite crucible and wrapped with coke powder (particle size greater than 3mm, washed until there is no micropowder particles on the surface and completely dried), placed in a muffle furnace, heated to 1000°C with the furnace, and taken out after 60 minutes for measuring its hot strength.

[0028] The present invention adopts the method of measuring the wear index of the granulated product as the cold and hot strength characterization method of the granulated product. The present invention adopts the reduction pulverization drum to detect the wear index of the product particles, the drum size is Φ130×200mm, the speed is 30 rpm, and the time is 10 minutes. Each time, 100g of granular materials distributed in 100-1000μm are weighed for the experiment, and the arithmetic mean value is taken as the wear index RDI after repeating 3 times.

[0029]

[0030] Where: m D0 —The mass of the sample before drum rotation;

[0031] m D1 —Mass after drumming +0.01mm.

[0032] In the embodiment, TiCl 4 The chemical composition of the distillation residue during the refining process is: TiCl 4 ≥85wt%;AlCl 3 3~5wt%;FeCl 3 0~1wt%.

[0033] The process of the present invention is described below in conjunction with specific embodiments.

[0034] Example 1

[0035] Weigh 20g TiCl 4 The residual liquid from the distillation kettle during the refining process was evenly mixed with 1000g of fine-grained artificial rutile (particle size less than 100μm), placed in a wet high-speed stirring granulator, and the stirring paddle speed was set to 400rpm, the cutting knife speed was set to 1500rpm, and the granulation time was 4 minutes. The granulated product particles were placed in a fluidized bed dryer for drying, and the particle size distribution was obtained between 100 and 1000μm, accounting for 89%, the particle dry strength wear index was 7.96%, and the particle 1000℃ thermal strength wear index was 4.62%.

[0036] Example 2

[0037] Weigh 1000g of fine-grained high-titanium slag (particle size less than 100μm) and place it in a V-type mixer granulator. Add 40g of TiCl at a speed of 40r / min through the built-in stirring system of the mixer. 4 After the residual liquid from the distillation kettle in the refining process is fully mixed, the speed of the stirring rod is set to 1500-3000r / min, and the granulated product particles are placed in a fluidized bed dryer for drying. The particle size distribution is between 100 and 1000μm, accounting for 90%, the particle drying strength wear index is 8.36%, and the particle 1000℃ thermal strength wear index is 5.22%.

[0038] Example 3

[0039] Weigh 30g TiCl 4 1000g of fine-grained artificial rutile (particle size less than 100μm) from the residual liquid of the distillation kettle during the refining process is evenly mixed with the binder and placed in a wet high-speed stirring granulator. The stirring paddle speed is set to 400rpm, the cutting knife speed is set to 1500rpm, and the granulation time is 3 minutes. The granulated product particles are placed in a fluidized bed dryer for drying, and the particle size distribution is between 100 and 1000μm, accounting for 92%. The particle dry strength wear index is 4.35%, and the particle 1000℃ thermal strength wear index is 3.62%.

[0040] Example 4

[0041] Weigh 1000g of fine-grained artificial rutile (particle size less than 100μm) and put it into a fluidized bed granulator with a fluidization speed of 0.23m / s and a material filling rate of 0.9%. 4 The residual liquid from the distillation kettle during the refining process is sprayed into the atomizer of the fluidized bed granulator. The dispersed binder liquid is distributed to the surface of the material, mixed and condensed into particles under the action of pneumatics, the atomization pressure is 0.2MPa, and the spraying time is 60min. The granulated product is dried and consolidated under the action of fluidized air, and the particle size distribution of the obtained particles is between 100 and 1000μm, accounting for 86.56%. The particle dry strength wear index is 6.39%, and the particle 1000℃ thermal strength wear index is 4.36%.

[0042] Comparative Example 1

[0043] Weigh 30g of ferrous sulfate and 200g of water to prepare a binder solution for use. Evenly mix the binder solution with 1000g of fine-grained artificial rutile (particle size less than 100μm), place it in a wet high-speed stirring granulator, set the stirring paddle speed to 400rpm, the cutting knife speed to 1200rpm, and the granulation time to 4 minutes. The granulated product particles are placed in a fluidized bed dryer for drying, and the particle size distribution between 100 and 1000μm accounts for 46.23%, the particle dry strength wear index is 15.66%, and the particle 1000℃ thermal strength wear index is 8.96%.

[0044] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. For those skilled in the art, improvements and changes obtained without departing from the technical concept of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for recycling the residual liquid from the distillation kettle in the titanium tetrachloride refining process, It is characterized in that The following steps are involved: (1) Weigh the residual liquid: weigh TiCl according to the set ratio 4 The residual liquid from the distillation kettle during the refining process is used as a binder; (2) Raw material mixing: Spray the binder evenly into the fine titanium-rich material and mix well; (3) Granulation: placing the mixed raw materials in a granulator for granulation; (4) Drying and solidification: Drying and solidifying the granulated product to obtain a granulated product of titanium-rich material.

2. A method for recycling residual liquid from a distillation kettle in a titanium tetrachloride refining process according to claim 1, It is characterized in that The fine titanium-rich material is high-titanium slag or artificial rutile with a particle size less than 100 μm after chemical treatment.

3. A method for recycling residual liquid from a distillation kettle in a titanium tetrachloride refining process according to claim 1, It is characterized in that In step (1), TiCl 4 The chemical composition of the distillation residue in the refining process is: TiCl 4 ≥85wt%; AlCl 3 3~5wt%; FeCl 3 0~1wt%。 4. A method for recycling residual liquid from a distillation kettle in a titanium tetrachloride refining process according to claim 1, It is characterized in that In step (1), TiCl 4 The amount of residual liquid in the distillation kettle during the refining process is 2-8wt% of the amount of fine-grained titanium-rich material.

5. A method for recycling residual liquid from a distillation kettle in a titanium tetrachloride refining process according to claim 1, It is characterized in that In step (3), the granulation method of the fine titanium-rich material includes any one of a fluidized bed granulation method, a disc granulation method, a V-type mixer granulation method and a high-speed stirring granulation method.

6. A method for recycling residual liquid from a distillation kettle in a titanium tetrachloride refining process according to claim 1, It is characterized in that In step (4), the particle size of the granulated product is 100 μm to 1000 μm, accounting for more than 90%, and the composition and particle strength meet the requirements of boiling chlorination.

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