阅读说明：本技术 一种使用富钛细粉料制备氯化法TiO2原料的方法 (Preparation of chlorination-process TiO by using titanium-rich fine powder2Method for preparing raw material ) 是由 陈建立 张坤 肖莎莎 张曼 冯娜 于 2019-09-29 设计创作，主要内容包括：本发明提供了一种使用富钛细粉料制备氯化法TiO_2原料的方法,包括以下步骤：S1：取所述富钛细粉料,并与固体有机粘结剂、石油焦在室温下混合均匀；S2：在步骤S1得到的混合物料表面均匀覆盖石油焦,然后在380～420℃下低温焦化2.5～4h；S3：将步骤S2低温焦化后的物料首次破碎至颗粒,然后在900～1200℃下高温焦化20～60min,再次破碎至颗粒,得到所述氯化法TiO_2原料。本发明可得到收率高(高于92％)、粒度合格的氯化法TiO_2原料,实现了富钛细粉料的循环利用,而且通过提前配入石油焦,减少了后期氯化反应的配料程序。(The invention provides a method for preparing TiO by chlorination by using titanium-rich fine powder 2 A method of feedstock comprising the steps of: s1: taking the titanium-rich fine powder, and uniformly mixing the titanium-rich fine powder with a solid organic binder and petroleum coke at room temperature; s2: evenly covering petroleum coke on the surface of the mixed material obtained in the step S1, and then coking at 380-420 ℃ for 2.5-4 h; s3: crushing the material coked at the low temperature in the step S2 for the first time to particles, then coking at the high temperature of 900-1200 ℃ for 20-60 min, crushing again to particles to obtain the chlorination-process TiO 2 Raw materials. The invention can obtain TiO by chlorination method with high yield (higher than 92%) and qualified granularity 2 The raw materials realize the recycling of the titanium-rich fine powder, and the batching procedure of the later chlorination reaction is reduced by adding petroleum coke in advance.)

1. Preparation of chlorination-process TiO by using titanium-rich fine powder₂A method of feedstock, comprising the steps of:

S1: taking the titanium-rich fine powder, and uniformly mixing the titanium-rich fine powder with a solid organic binder and petroleum coke at room temperature, wherein the use amounts of the solid organic binder and the petroleum coke are respectively 5-25% and 6-24% of the mass of the titanium-rich fine powder;

S2: evenly covering petroleum coke on the surface of the mixed material obtained in the step S1, and then coking at 380-420 ℃ for 2.5-4 h;

s3: crushing the material coked at the low temperature in the step S2 for the first time to particles, then coking at the high temperature of 900-1200 ℃ for 20-60 min, crushing again to particles to obtain the chlorination-process TiO₂Raw materials.

2. preparation of chlorinated TiO from titanium-rich fines according to claim 1₂A method for producing a starting material, characterized in that,

The particle size of the titanium-rich fine powder is less than 200 meshes.

3. Preparation of chlorinated TiO from titanium-rich fines according to claim 2₂A method for producing a starting material, characterized in that,

The titanium-rich fine powder is TiO₂grade greater than 95%, (CaO + MgO)%<0.5 percent of titanium-rich material.

4. Preparation of chlorinated TiO from titanium-rich fines according to claim 3₂A method for producing a starting material, characterized in that,

The titanium-rich fine powder is a low-concentration titanium liquid hydrolysis material.

5. Preparation of chlorinated TiO from titanium-rich fines according to claim 1₂a method for producing a starting material, characterized in that,

the solid organic binder is any one or a combination of more than two of coal tar, coal pitch, petroleum pitch and phenolic resin.

6. Preparation of chlorinated TiO from titanium-rich fines according to claim 1₂A method for producing a starting material, characterized in that,

the thickness of the petroleum coke covered by the step S2 is 1-2 mm.

7. Preparation of chlorinated TiO from titanium-rich fines according to claim 1₂A method for producing a starting material, characterized in that,

In the step S3, the granularity of the primary crushed particles is 20-60 meshes.

8. Preparation of chlorinated TiO from titanium-rich fines according to claim 7₂A method for producing a starting material, characterized in that,

the granularity of the re-crushed particles is 20-160 meshes.

Technical Field

The invention belongs to the technical field of preparation of titanium dioxide raw materials by a chlorination process, and particularly relates to a method for preparing TiO by the chlorination process by using titanium-rich fine powder₂A method for the preparation of a feedstock.

background

At present, TiO₂the production process mainly comprises a sulfuric acid method and a chlorination method, and the two methods respectively have the advantages and the disadvantages: the sulfuric acid method has mature process, simple equipment and low requirement on raw materials, is widely adopted, but has process flowThe process is long, the operation is complex and more three wastes are generated; the chlorination method has more and more attention due to the advantages of advanced production technology, high yield, simple process, low energy consumption, excellent product performance and the like, but has higher requirements on raw materials, the titanium grade is required to be more than 85 percent, the impurity content is less (CaO is less than 0.15 percent, CaO and MgO are less than 1.5 percent), and the foreign imported high-quality raw material UGS (a high-grade chlorination method raw material removes impurities such as Ca, Mg, Fe and the like from titanium slag to improve the Ti grade, and the produced titanium slag TiO is₂The content reaches about 95 percent, and the slag is called UGS) and the like, and the price is higher, thereby greatly improving the production cost.

Titanium ore resources are rich in Panxi areas in China, but gangue content is high, selectivity is poor, and concentrate grade is low, so that the titanium ore can not be directly used as raw materials for a chlorination method. The method for preparing the titanium-rich material by hydrolyzing the low-concentration titanium solution effectively combines the advantages of a sulfuric acid method and a chlorination method, utilizes the advantage of low requirement on raw materials of the sulfuric acid method, carries out acidolysis and hydrolysis on titanium ore to prepare metatitanic acid, and then prepares the titanium-rich material as the raw material of the chlorination method after washing, calcining and crushing, thereby greatly reducing the generation of three wastes of the sulfuric acid method, solving the problem of high import price of raw materials of the chlorination method, and being high-quality TiO₂A new production idea. The method can generate a certain amount of fine powder with particle size below 200 meshes and TiO in the crushing process₂Grade greater than 95%, (CaO + MgO)%<0.5 percent, small tap density and easy to be blown away by chlorine in a boiling chlorination furnace, so the raw material can not be directly put into the chlorination furnace, but the components of the raw material are the same as those of the qualified granularity material, thereby greatly reducing the yield, causing the waste of titanium resources if the raw material can not be well recycled, and simultaneously generating a certain amount of solid pollutants.

Regarding the recycling of the fine powder, many researchers have studied titanium-containing fine powder such as titanium slag fine powder, artificial rutile fine powder, fluidized bed reactor ash and the like, and some enterprises can adopt a return electric furnace for secondary smelting, but the electric energy cost is increased.

On the other hand, in the chlorination process, not only titanium materials need to be put into the fluidized bed chlorination furnace at present, but also petroleum coke in a certain proportion needs to be put into the fluidized bed chlorination furnace to react with the titanium materials so as to provide a reducing atmosphere, so that the petroleum coke and the titanium materials are not required to be burdened in a certain working hour before the fluidized bed chlorination furnace is produced, and the petroleum coke needs to be calcined.

Patent CN104058450A discloses a "granulation method of titanium coke particles", which specifically discloses a granulation method of heating, mixing, fractionating, coking, crushing, grading, calcining and other processes of a mixture of a fine-grained titanium-containing material and a high molecular hydrocarbon to prepare a raw material meeting the requirements of a chlorination process, but the patent requires that the raw materials are respectively heated and then mixed at 350-450 ℃, so that the industrial implementation has high requirements on equipment and high cost.

Patent CN109761271A discloses a method for recycling titanium-containing fines, which specifically discloses a chlorination method raw material with qualified particle size prepared by mixing titanium-containing fines, water and a binder in a certain proportion, and performing extrusion forming, calcination, crushing, screening and other processes.

disclosure of Invention

The invention aims to solve the defects of the prior art and provide a method for preparing TiO by chlorination by using titanium-rich fine powder₂A method for the preparation of a feedstock.

The purpose of the invention is realized by the following technical scheme:

preparation of chlorination-process TiO by using titanium-rich fine powder₂A method of feedstock comprising the steps of:

S1: taking the titanium-rich fine powder, and uniformly mixing the titanium-rich fine powder with a solid organic binder and petroleum coke at room temperature, wherein the use amounts of the solid organic binder and the petroleum coke are respectively 5-25% and 6-24% of the mass of the titanium-rich fine powder;

s2: evenly covering petroleum coke on the surface of the mixed material obtained in the step S1, and then coking at 380-420 ℃ for 2.5-4 h;

s3: crushing the material coked at the low temperature in the step S2 for the first time to particles, then coking at the high temperature of 900-1200 ℃ for 20-60 min, crushing again to particles to obtain the chlorination-process TiO₂Raw materials.

Preferably, the particle size of the titanium-rich fine powder is less than 200 meshes.

preferably, the titanium-rich fine powder is TiO₂Grade greater than 95%, (CaO + MgO)%<0.5 percent of titanium-rich material.

Preferably, the titanium-rich fine powder is a low-concentration titanium liquid hydrolysate.

Preferably, the solid organic binder is one or a combination of two or more selected from coal tar, coal pitch, petroleum pitch and phenolic resin.

preferably, the thickness of the petroleum coke covered by the step S2 is 1-2 mm.

Preferably, the particle size of the first crushed particles in the step S3 is 20-60 meshes.

Preferably, the particle size of the re-crushed particles is 20-160 meshes.

according to the invention, the solid organic binder and the petroleum coke are added into the titanium-rich fine powder, then the mixture is mixed at room temperature, and then a layer of petroleum coke is covered to isolate air, so that the using amount of the binder is reduced, then the low-temperature coking is carried out, and then the high-temperature coking is carried out, so that the titanium-rich fine powder and the petroleum coke are tightly wrapped by a net structure generated by the binder, the regeneration of the fine powder is reduced, and the chlorination-process TiO with high yield (higher than 92%) and qualified granularity is obtained₂The raw material realizes the cyclic utilization of the titanium-rich fine powder, and the petroleum coke is added in advance, so that the batching procedure of the later chlorination reaction is reduced, the petroleum coke is coked, and during coking, molecules of the petroleum coke and the titanium-containing fine powder can pass through bones formed by a solid organic binderThe racks are connected, so that the racks are connected tightly in the subsequent chlorination reaction, the racks cannot be blown away by chlorine, the layering phenomenon occurs, and the reaction is more sufficient. In addition, the method is simple to operate, short in process flow and reaction time, easy to realize industrial production and capable of improving production efficiency.

Detailed description of the preferred embodiments

in order to better understand the above technical solutions, the above technical solutions will be described in detail in the following embodiments of the combination.

The invention provides a method for preparing TiO by chlorination by using titanium-rich fine powder₂a method of feedstock comprising the steps of:

S1: taking the titanium-rich fine powder, and uniformly mixing the titanium-rich fine powder with a solid organic binder and petroleum coke at room temperature, wherein the use amounts of the solid organic binder and the petroleum coke are respectively 5-25% and 6-24% of the mass of the titanium-rich fine powder; compared with a liquid binder, the solid organic binder has the advantages that a carbon skeleton can be formed by the change of functional groups after heat treatment to bond materials together, the caking property is good, the using amount is small, certain carbon is remained after coking, and some reducing atmosphere can be provided in the subsequent chlorination process; the organic binder added in a liquid form is slow in dissolving process, and the liquid binder is mixed with a large amount of solid titanium-rich fine powder and petroleum coke, so that the phenomenon of uneven mixing is easy to occur.

S2: uniformly covering a layer of petroleum coke on the surface of the mixed material obtained in the step S1, and then coking the mixed material at 380-420 ℃ for 2.5-4 h; the heat loss of the adhesive is reduced while air is isolated, so that the cost can be effectively reduced;

S3: crushing the material coked at the low temperature in the step S2 for the first time to particles, then coking at the high temperature of 900-1200 ℃ for 20-60 min, crushing again to particles to obtain TiO by a chlorination process₂raw materials. The low-temperature coking material is crushed into particles before high-temperature coking, which is beneficial to coking, otherwise, the flaky mixture is mixedThe composite material is difficult to coke uniformly.

The invention takes titanium-rich fine powder as raw material, uses solid organic binder for granulation, and utilizes a net structure generated by the binder at high temperature to wrap and bond the material, so as to prepare the TiO prepared by the chlorination method₂The required raw materials.

Specifically, the titanium-rich fine powder is uniformly mixed with the solid organic binder and petroleum coke at room temperature, compared with the prior art, the asphalt heat mixing method has lower requirement on equipment and reduces the extrusion forming process, meanwhile, because the material oil absorption of the invention is large, the addition amount of the binder can be greatly reduced by normal temperature mixing, the cost is reduced, and a layer of petroleum coke is covered before low-temperature coking, so that the heat loss of the binder is reduced while air is isolated, and the cost can be effectively reduced. Then high-temperature coking is carried out to prepare the TiO which meets the requirement of the chlorination method₂The required raw materials. Two-stage coking is adopted, wherein the solid binder can be changed into liquid at the low-temperature coking temperature, the liquid is better contacted with the titanium-containing fine material and the petroleum coke, and the heat generated by the low-temperature coking can be collected for recycling production, so that the heat circulation is realized, and the production cost is reduced; high-temperature coking can enable solid adhesives such as asphalt and the like to form a net structure, fine powder and petroleum coke are uniformly wrapped together, chlorination reaction in the later period cannot be blown away, and the strength of the coked materials is improved.

Compared with the existing addition mode of the raw materials by the chlorination method, the petroleum coke added in the earlier stage of the invention is enough to provide the following reducing atmosphere, the materials with qualified granularity after crushing can be directly used as the raw materials of the chlorination furnace, the reducing agent does not need to be added in proportion again, the later-stage charging and mixing process of the chlorination furnace is omitted, the production process is optimized, the production efficiency is improved, meanwhile, the petroleum coke is completely coked in the coking process of the mixed materials, and the petroleum coke and the molecules of titanium-containing fine powder can be connected through a framework formed by a solid organic binder during coking, so that the petroleum coke and the titanium-containing fine powder are connected closely during the chlorination reaction, cannot be blown away by chlorine, the layering phenomenon.

Compared with the CN104058450A patent of 'a granulation method of titanium coke particles', the adopted raw materials are different, the material mixing temperature is lower (the mixing temperature of the CN104058450A patent is 350-450 ℃), the titanium-rich material fine powder adopted by the method is similar to titanium dioxide in property, the surface hydroxyl group is many, the oil absorption is large compared with the materials such as artificial rutile, acid sludge and the like, if solid binders such as asphalt and the like are consumed by high-temperature mixing, the cost input and the energy consumption of production equipment are reduced by selecting normal-temperature mixing. And this application covers one deck petroleum coke on the material surface when preliminary coking, and the heat loss of isolated air reduction binder has also guaranteed the bonding effect of binder simultaneously. Compared with the CN109761271A patent of 'a method for recycling titanium-containing fine materials', the raw materials and the binder adopted by the method are different, the extrusion forming process is reduced, and the equipment cost is reduced. And this application adds a certain amount of petroleum coke at the compounding stage, has increased reducing atmosphere at the coking process, has simplified the batching process of follow-up chlorination stove, and petroleum coke is through the coking in addition, and the coking in-process is closely connected with the titanium material under the effect of solid organic binder, in the follow-up chlorination reaction, can not blown away by chlorine, takes place the layering phenomenon, and the reaction is more abundant.

Wherein, the particle size of the titanium-rich fine powder is preferably less than 200 meshes, and the TiO powder is TiO₂Grade greater than 95%, (CaO + MgO)%<0.5 percent of titanium-rich material. The titanium-rich fine powder is preferably low-concentration titanium liquid hydrolysate or other titanium fine powder meeting the requirements.

The solid organic binder of step S1 of the present invention is formed into a mesh structure at high temperature mainly by using the carbon skeleton, so that the titanium material and the petroleum coke can be tightly bound. Therefore, a solid organic binder with a large molecular weight can be selected, the binder with the large molecular weight has a large carbon chain, and the binding effect of the later coking is better, and preferably, the solid organic binder in the step S1 is one or a combination of more than two of coal tar, coal tar pitch, petroleum pitch and phenolic resin.

The thickness of the petroleum coke covered by the step S2 is 1-2 mm.

Preferably, the particle size of the first crushed particles in the step S3 is 20-60 meshes.

preferably, the size of the re-crushed particles is 20 to 160 mesh, or other desired sizes.