Micro-fine particle titanium-rich material granulation method based on acid binder

Abstract

The invention discloses a micro-fine particle titanium-rich material granulation method based on an acid binder, which comprises the following steps: (1) preparing a binder solution: weighing a binder and water according to a set proportion to prepare the binder solution; the binder is one or a combination of hydrochloric acid and sulfuric acid; (2) raw material mixing: uniformly spraying the prepared binder solution into the micro-fine particle titanium-rich material, and uniformly mixing; (3) granulating, namely granulating the uniformly mixed raw materials in a granulator; and (4) drying and curing: drying and curing the granulated product. According to the preparation method, a titanium-rich material front-end preparation process is combined, acid is adopted as a granulation binder, and through chemical reaction between the binder and the raw materials, particles are mutually bonded and have certain strength. The micro-fine particle titanium-rich material granulation method based on the acid binder is of great significance to comprehensive utilization of titanium resources in China.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium resource utilization and relates to a method for granulating fine titanium-rich materials based on an acid binder. Background Art

[0002] Titanium is an important strategic metal in my country and has important applications in aerospace, navigation, military industry, daily chemical industry and other fields. The main products of the titanium industry are titanium dioxide, titanium metal and titanium alloys. About 95% of the world's titanium resources are used to produce titanium dioxide. The boiling chlorination method has simple production equipment, large titanium tetrachloride output, and low three waste emissions. It is the mainstream process for the production of titanium dioxide by the chlorination method in my country. The boiling chlorination method requires that the calcium and magnesium impurity content of the raw materials entering the furnace is less than 1.5%, of which CaO is less than 0.14%, and the titanium grade is ≥90%. The boiling chlorination furnace is a fluidized bed system. In order to ensure that the titanium-rich material always maintains a fluidized state in the boiling chlorination furnace, the particle size distribution of the raw materials entering the furnace is required to be between 100 and 1000 μm.

[0003] my country's titanium resources are mainly found in ilmenite, usually 40% to 45%. In order to make ilmenite available for boiling chlorination production, it needs to be enriched into high-grade titanium-rich materials (artificial rutile, high-titanium slag). my country's ilmenite contains a lot of calcium and magnesium impurities, which need to be removed by grinding and acid leaching to obtain titanium-rich materials. This process makes the obtained titanium-rich materials finer in particle size, and acid ions are attached to the surface of the titanium-rich material particles. Therefore, domestic titanium-rich materials need to be granulated before being put into boiling chlorination process.

[0004] In order to increase the particle size of titanium-rich materials to meet the requirements of the boiling chlorination process, researchers used various granulation processes to granulate artificial rutile. Patent CN105271390B uses heavy oil, sodium cellulose, and dextrin to form a composite binder, and uses disc granulation to process artificial rutile. The final product particle size distribution is 0.45-1mm. Patent CN102776365A uses edible flour and polyacrylamide as organic-organic composite binders, and the particles are bonded into agglomerates by stirring. The paper "Study on the fluidized bed granulation of fine-grained rutile concentrate" uses sodium carboxymethyl cellulose as a binder, and processes natural rutile by fluidized bed granulation. The average particle size of the granulated product is 103μm. Patent CN106319246B uses caustic soda (NaOH, KOH) as a binder, and adopts agglomeration granulation or fluidized bed granulation. The final product particle size is basically greater than 100μm. Patent CN114702062B uses aluminum sulfate as a binder and high-speed stirring granulation. The final particle size distribution is between 150 and 1000 μm, accounting for more than 90%. Patent CN114702061B uses ferrous sulfate and silica sol as binders, which are suitable for various granulation processes such as disc granulation, high-speed stirring granulation, and fluidized bed granulation. Fine-grained titanium-rich materials can have a good granulation effect. However, the above-mentioned binder composition is complex, which not only increases the cost, but also introduces additional impurities, reducing the quality of titanium dioxide. Summary of the invention

[0005] In order to solve the problems in the background technology, the purpose of the present invention is to provide a method for granulating fine-grained titanium-rich materials based on acid binders, by adding acid binders to form new chemical substances as particle binding phases, so that the fine-grained titanium-rich material particles are agglomerated.

[0006] The present invention provides a method for granulating a fine titanium-rich material based on an acid binder, comprising the following steps:

[0007] (1) preparing a binder solution: weighing a binder and water according to a set ratio to prepare a binder solution; the binder is one or a combination of hydrochloric acid and sulfuric acid;

[0008] (2) Raw material mixing: Spray the prepared binder solution evenly into the fine titanium-rich material and mix well;

[0009] (3) Granulation: placing the mixed raw materials in a granulator for granulation;

[0010] (4) Drying and solidification: Drying and solidifying the granulated product.

[0011] In a preferred embodiment, in step (1), the pH range of the prepared binder solution is 1 to 6.

[0012] In a preferred embodiment, in step (2), the fine-grained titanium-rich material is subjected to an acid leaching treatment to remove impurities, and its particle size is less than 100 μm.

[0013] In a preferred embodiment, in step (2), the fine titanium-rich material and the binder solution are evenly mixed, with a solid-liquid ratio of 50 to 10:1.

[0014] In a preferred embodiment, in step (3), the granulating equipment used is any one of a high-speed stirring granulator, a V-type mixing granulator, a fluidized bed granulator, and a disc granulator.

[0015] In a preferred embodiment, in step (4), the granulated product particles are placed in an environment of 105 to 400° C. for drying and consolidation to obtain a granulated product with a particle size distribution of 100 to 1000 μm.

[0016] The present invention relates to the following reaction mechanism:

[0017] After acid leaching, some acid ions adhere to the surface of the fine titanium-rich material, which are easy to combine with the hydrogen ions in the binder to form chemical bonds, thereby promoting the bonding between particles. At the same time, the titanium-rich material contains some impurities such as Fe2O3 and Al2O3, which react with acid (1)-(4) to form new chemical substances that become the particle bonding phase.

[0018] Fe2O3+6HCl→2FeCl3+3H2O (1)

[0019] Fe2O3+3H2SO4→Fe2(SO4)3+3H2O (2)

[0020] Al2O3+6HCl→2AlCl3+3H2O (3)

[0021] Al2O3+3H2SO4→Al2(SO4)3+3H2O (4)

[0022] Beneficial technical effects of this invention:

[0023] The present invention provides a method for granulating fine titanium-rich materials based on an acid binder, wherein a binder solution is prepared by using hydrochloric acid, sulfuric acid or a mixture of the two and water, and the prepared binder solution is sprayed on fine titanium-rich material particles less than 100 μm 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 particles with a particle size distribution between 100 and 1000 μm are measured.

[0024] The present invention combines the front-end preparation process of titanium-rich materials, uses acids as granulation binders, and through the chemical reaction between the binder and the raw materials, the particles are bonded to each other and have a certain strength. The present invention proposes a method for granulating fine titanium-rich materials based on acid binders, which is of great significance to the comprehensive utilization of my country's titanium resources. 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] 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.

[0027] 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.

[0028]

[0029] Where: m D0 —The mass of the sample before drum rotation;

[0030] m D1 —Mass after drumming +0.01mm.

[0031] The process of the present invention is described below in conjunction with specific embodiments.

[0032] Example 1

[0033] Use hydrochloric acid to prepare a binder solution with a pH of 1 for standby use. Weigh 1000g of fine-grained artificial rutile (particle size less than 100μm) and mix it evenly with the binder solution. The solid-liquid ratio is 50:1. Place it in a wet high-speed stirring granulator, set the stirring paddle speed to 400rpm, the cutting knife speed to 1500rpm, and the granulation time to 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 89.54%, the particle dry strength wear index is 6.22%, and the particle 1000℃ thermal strength wear index is 3.96%.

[0034] Example 2

[0035] Use hydrochloric acid to prepare a binder solution with a pH of 6 for standby use, weigh 1000g of fine-grained high-titanium slag (particle size less than 100μm) and mix it evenly with the binder solution, with a solid-liquid ratio of 40:1. Place it in a V-type mixing granulator, add the binder solution at a speed of 40r / min through the built-in stirring system of the mixer, and after sufficient mixing, set the stirring rod speed to 1500-3000r / min, and place the granulated product particles in a fluidized bed dryer for drying, and obtain particles with a particle size distribution between 100 and 1000μm, accounting for 85.35%, the particle dry strength wear index is 9.36%, and the particle 1000℃ thermal strength wear index is 4.65%.

[0036] Example 3

[0037] Use sulfuric acid to prepare a binder solution with a pH of 3 for standby use. Weigh 1000g of fine-grained artificial rutile (particle size less than 100μm) and mix it evenly with the binder solution. The solid-liquid ratio is 10:1. Place it in a wet high-speed stirring granulator, set the stirring paddle speed to 400rpm, the cutting knife speed to 1500rpm, and the granulation time to 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 86.56%. The particle dry strength wear index is 6.39%, and the particle 1000℃ thermal strength wear index is 4.36%.

[0038] Example 4

[0039] Use sulfuric acid to prepare a binder solution with a pH of 2 for standby use. Weigh 1000g of fine-grained artificial rutile (particle size less than 100μm) and put it into a fluidized bed granulator. The fluidization speed is 0.23m / s and the material filling rate is 0.9%. The prepared binder solution is sprayed through the atomizer of the fluidized bed granulator, and the ratio of binder to raw material is 10:1. 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 wind, and the particle size distribution between 100 and 1000μm accounts for 86.56%. The particle dry strength wear index is 6.39%, and the particle 1000℃ thermal strength wear index is 4.36%.

[0040] Comparative Example 1

[0041] Weigh 1000g of fine-grained artificial rutile (particle size less than 100μm) and mix it evenly with water, with a solid-liquid ratio of 10:1. Place it in a wet high-speed stirring granulator, set the stirring paddle speed to 400rpm, the cutting knife speed to 1500rpm, and the granulation time to 3 minutes. Place the granulated product particles in a fluidized bed dryer for drying, and the particle size distribution between 100 and 1000μm accounts for 35.36%. The granulation effect is poor.

[0042] Comparative Example 2

[0043] Weigh 30g of aluminum sulfate and put it into 200g of water to prepare a binder solution for standby use. Weigh 1000g of fine-grained artificial rutile (particle size less than 100μm) and mix it evenly with the binder, place it in a wet high-speed stirring granulator, set the stirring paddle speed to 400rpm, the cutting knife speed to 1000rpm, and the granulation time to 6 minutes. The granulated product particles are placed in a fluidized bed dryer for drying, and the particle size distribution obtained is between 96 and 900μm, accounting for 46.78%. The granulation efficiency of fine-grained artificial rutile is poor.

[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 granulating fine titanium-rich materials based on an acid binder, characterized in that: The following steps are involved: (1) preparing a binder solution: weighing a binder and water according to a set ratio to prepare a binder solution; the binder is one or a combination of hydrochloric acid and sulfuric acid; (2) Raw material mixing: Spray the prepared binder solution 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.

2. A method for granulating a fine-grained titanium-rich material based on an acid binder according to claim 1, characterized in that: In step (1), the pH range of the prepared binder solution is 1 to 6.

3. The method for granulating a fine-grained titanium-rich material based on an acid binder according to claim 1, characterized in that: In step (2), the fine-grained titanium-rich material is treated by acid leaching to remove impurities, and its particle size is less than 100 μm.

4. The method for granulating a fine-grained titanium-rich material based on an acid binder according to claim 1, characterized in that: In step (2), the fine titanium-rich material and the binder solution are mixed evenly with a solid-liquid ratio of 50 to 10:

1.

5. The method for granulating a fine-grained titanium-rich material based on an acid binder according to claim 1, characterized in that: In step (3), the granulation equipment used is any one of a high-speed stirring granulator, a V-type mixing granulator, a fluidized bed granulator, and a disc granulator.

6. The method for granulating a fine-grained titanium-rich material based on an acid binder according to claim 1, characterized in that: In step (4), the granulated product particles are placed in an environment of 105 to 400° C. for drying and consolidation to obtain a granulated product with a particle size distribution of 100 to 1000 μm.

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