阅读说明：本技术 提钛渣制备辅助胶凝材料的方法以及一种辅助胶凝材料 (Method for preparing auxiliary cementing material by extracting titanium slag and auxiliary cementing material ) 是由 孙红娟 唐颂 彭同江 于 2021-08-31 设计创作，主要内容包括：本发明提供了一种提钛渣制备辅助胶凝材料的方法以及一种辅助胶凝材料,所述方法包括步骤：将提钛渣水洗至其中可溶性氯离子完全溶出,得到第一滤渣和第一滤液,所述第一滤液中主要成分为氯化钙和氯化镁；将所述第一滤渣干燥后粉磨得到第一粒径粉体；将所述第一粒径粉体继续进行水洗使其中氯离子含量降至万分之二以下,过滤得到第二滤渣和第二滤液；将所述第二滤渣烘干并机械活化得到第二粒径粉体,所述第二粒径粉体即可作为辅助胶凝材料使用。本发明具有采用水浸去除提钛渣中的氯离子,借助水浸后滤渣不吸湿的特点,进行二次水浸,充分去除残留的氯离子、制得高活性活性高达S105级以上的超活性类矿渣微粉、节能环保、提高产品附加值等优点。(The invention provides a method for preparing an auxiliary cementing material by extracting titanium slag and the auxiliary cementing material, wherein the method comprises the following steps: washing the titanium extraction slag with water until soluble chloride ions are completely dissolved out to obtain first filter residue and first filtrate, wherein the main components of the first filtrate are calcium chloride and magnesium chloride; drying the first filter residue and then grinding to obtain powder with a first particle size; continuously washing the powder with the first particle size to reduce the content of chloride ions to below two ten-thousandth, and filtering to obtain second filter residue and second filtrate; and drying and mechanically activating the second filter residue to obtain powder with a second particle size, wherein the powder with the second particle size can be used as an auxiliary cementing material. The method has the advantages of removing chloride ions in the titanium extraction slag by adopting water leaching, fully removing residual chloride ions by secondary water leaching by means of the characteristic that filter residues after water leaching do not absorb moisture, preparing the super-active slag micro powder with high activity reaching above S105 level, saving energy, protecting environment, improving the added value of products and the like.)

1. The method for preparing the auxiliary cementing material by extracting the titanium slag is characterized by comprising the following steps of:

washing the titanium extraction slag with water until soluble chloride ions are completely dissolved out to obtain first filter residue and first filtrate, wherein the main components of the first filtrate are calcium chloride and magnesium chloride;

drying the first filter residue and then grinding to obtain powder with a first particle size;

continuously washing the powder with the first particle size to reduce the content of chloride ions to below two ten-thousandth, and filtering to obtain second filter residue and second filtrate;

and drying and mechanically activating the second filter residue to obtain powder with a second particle size, wherein the powder with the second particle size is the auxiliary cementing material.

2. The method for preparing the auxiliary cementing material by extracting the titanium slag according to the claim 1, characterized in that the method further comprises the following steps:

evaporating and concentrating the first filtrate, adding sodium hydroxide or aluminum chloride solution to completely precipitate magnesium ions and aluminum ions in the first filtrate to generate magnesium hydroxide and aluminum hydroxide, washing and filtering to obtain third filter residue and third filtrate;

adding a sodium carbonate solution to the third filtrate to make Ca in the third filtrate²⁺Completely precipitating to generate calcium carbonate, and filtering to obtain a fourth filtrate and a fourth filter residue;

evaporating and concentrating the fourth filtrate by utilizing waste heat generated by low-temperature chlorination of the titanium-containing slag to obtain a fourth filtrate concentrate;

and electrolyzing the fourth filtrate concentrated solution to respectively obtain hydrogen, chlorine and a sodium hydroxide solution, wherein the chlorine is circulated to the low-temperature chlorination stage of the titanium-containing slag to be used as a chlorine raw material.

3. The method for preparing the auxiliary cementing material by extracting titanium slag according to claim 2, wherein the evaporation and concentration temperature of the first filtrate is 60-120 ℃.

4. The method for preparing the auxiliary cementing material from the titanium extraction slag according to the claim 1, wherein the step of washing the titanium extraction slag until the soluble chloride ions are completely dissolved out comprises the step of carrying out water leaching, washing and filtering on the titanium extraction slag raw slag for a plurality of times until the content of the chloride ions in the first filter residue is less than 1 per thousand.

5. The method for preparing the auxiliary cementing material by extracting the titanium slag according to the claim 1, wherein the first filter residue is directly used as cement or cement concrete admixture after being dried, or used as an active mineral material, or used for preparing a building material by adopting an alkali activator.

6. The method for preparing the auxiliary cementing material by extracting titanium slag according to claim 1, wherein the particle size of the first powder is 200-600 meshes, and the particle size of the second powder is 1000-2500 meshes.

7. The method for preparing the auxiliary cementing material by extracting titanium slag according to claim 1, wherein chloride ions in the second powder bodySO content of less than two ten-thousandth₃The content is less than 0.6 percent, the ignition loss is less than or equal to 2.5 percent, and the specific surface area is more than or equal to 500m²/kg。

8. The method for preparing the auxiliary cementing material by extracting the titanium slag according to the claim 1, wherein the mechanical activation equipment is a jet mill or a Raymond mill.

9. Supplementary cementitious material, characterised in that it is obtained by a process according to any one of claims 1 to 8.

10. Supplementary cementitious material according to claim 1, characterised in that the content of chloride ions in the supplementary cementitious material is less than two ten thousandths, SO₃The content is less than 0.6 percent, the ignition loss is less than or equal to 2.5 percent, and the specific surface area is more than or equal to 500m²/kg。

Technical Field

The invention relates to the technical field of resource treatment and utilization of titanium extraction slag, in particular to a method for preparing an auxiliary cementing material from titanium extraction slag and an auxiliary cementing material.

Background

The steel-climbing group adopts a high-temperature carbonization-low-temperature selective chlorination process to extract titanium, and important progress and good effect are achieved. But because the process has a low-temperature chlorination link, a large amount of chlorine-containing titanium-extracting slag (the annual output reaches more than 10 wt) is generated. The titanium extraction slag has certain chemical reaction activity, but because the content of water-soluble chloride ions is high, and the mass percent of chlorine is usually between 2 and 7 percent, the titanium extraction slag cannot be directly used for cement and concrete admixture like common blast furnace slag, so that the titanium extraction slag is mainly stockpiled at present, occupies a large amount of land resources, has potential pollution hidden danger to the surrounding environment, causes great economic, environmental and social pressure to enterprises, and how to treat and utilize the chlorine-containing titanium extraction slag becomes a difficult problem to be solved in aspects of sustainable development, environmental protection and the like of the titanium extraction process.

Disclosure of Invention

The present invention aims to address at least one of the above-mentioned deficiencies of the prior art. For example, on the one hand, the invention provides a method for preparing the auxiliary cementing material from the titanium extraction slag, which realizes resource utilization of the titanium extraction slag, does not discharge three wastes in the whole process, and is energy-saving and environment-friendly. The invention also aims to provide an auxiliary cementing material which has excellent performance, can improve the early strength of concrete, improve the easy mixing property of the concrete and reduce the hydration heat.

In order to achieve the above object, the present invention provides a method for preparing an auxiliary cementitious material by extracting titanium slag, the method comprising the steps of:

washing the titanium extraction slag with water until soluble chloride ions are completely dissolved out to obtain first filter residue and first filtrate, wherein the main components of the first filtrate are calcium chloride and magnesium chloride;

drying the first filter residue and then grinding to obtain powder with a first particle size;

continuously washing the powder with the first particle size to reduce the content of chloride ions to below two ten-thousandth, and filtering to obtain second filter residue and second filtrate;

and drying and mechanically activating the second filter residue to obtain powder with a second particle size, wherein the powder with the second particle size is the auxiliary cementing material.

In an exemplary embodiment of an aspect of the present invention, the method may further include the steps of:

evaporating and concentrating the first filtrate, adding sodium hydroxide or aluminum chloride solution to completely precipitate magnesium ions and aluminum ions in the first filtrate to generate magnesium hydroxide and aluminum hydroxide, washing and filtering to obtain third filter residue and third filtrate;

adding a sodium carbonate solution to the third filtrate to make Ca in the third filtrate²⁺Completely precipitating to generate calcium carbonate, and filtering to obtain a fourth filtrate and a fourth filter residue;

evaporating and concentrating the fourth filtrate by utilizing waste heat generated by low-temperature chlorination of the titanium-containing slag to obtain a fourth filtrate concentrate;

and electrolyzing the fourth filtrate concentrated solution to respectively obtain hydrogen, chlorine and a sodium hydroxide solution, wherein the chlorine is circulated to the low-temperature chlorination stage of the titanium-containing slag to be used as a chlorine raw material.

In an exemplary embodiment of an aspect of the present invention, the temperature of the first filtrate for evaporative concentration may be 60 to 120 ℃.

In an exemplary embodiment of one aspect of the invention, the washing the titanium extraction slag until the soluble chloride ions are completely dissolved out may include subjecting the titanium extraction slag raw slag to water leaching, washing and filtering for a plurality of times until the chloride ion content in the first filter residue is less than 1% o.

In an exemplary embodiment of an aspect of the present invention, the first filter residue is dried and then used directly as a cement or cement concrete admixture, or as an active mineral material, or used for preparing a building material using an alkali activator.

In an exemplary embodiment of an aspect of the present invention, the first powder may have a particle size of 200 to 600 mesh, and the second powder may have a particle size of 1000 to 2500 mesh.

In an exemplary embodiment of an aspect of the present invention, the content of chloride ions in the second powder may be two parts per million or less, SO₃The content can be less than 0.6 percent, the ignition loss can be less than or equal to 2.5 percent, and the specific surface area can be more than or equal to 500m²/kg。

In an exemplary embodiment of an aspect of the present invention, the mechanical activation device may be a jet mill or a Raymond mill.

According to a further aspect of the present invention there is provided a supplementary cementitious material obtainable by a method as defined in any one of the preceding claims.

In an exemplary embodiment of another aspect of the present invention, the content of chloride ions in the supplementary cementitious material may be two parts per million or less, SO₃The content can be less than 0.6 percent, the ignition loss can be less than or equal to 2.5 percent, and the specific surface area can be more than or equal to 500m²/kg。

Compared with the prior art, the beneficial effects of the invention can comprise at least one of the following:

(1) the invention solves the problem that the resource utilization of the titanium extraction slag is difficult due to high chlorine content, which restricts the bottleneck of the titanium extraction process by a chlorination method, and leaches soluble chloride ions by water leaching and water washing, thereby greatly reducing the chlorine content in the slag and being beneficial to the resource utilization of the titanium extraction slag;

(2) aiming at chloride ions in the filtrate, the filtrate is subjected to chemical reaction graded treatment and recovery, products at all levels can be used as chemical raw materials or commodities for use and sale, and three wastes are not discharged in the whole process, so that the waste is changed into valuable, industrial solid waste resources are recycled, and the economic effect, resource environmental benefit and social benefit of the titanium extraction slag are greatly improved;

(3) the method effectively relieves the economic pressure and environmental protection pressure of enterprises, correspondingly saves land, reduces pollution, realizes the recycling of solid waste resources, saves natural materials, and has positive and practical significance for assisting national infrastructure and the like.

Detailed Description

Hereinafter, the method for preparing supplementary cementitious material from titanium slag and a supplementary cementitious material according to the present invention will be described in detail with reference to exemplary embodiments.

In a first exemplary embodiment of the present invention, a method for extracting titanium slag to prepare a supplementary cementitious material, the method comprising the steps of:

washing the titanium extraction slag with water until soluble chloride ions are completely dissolved out to obtain first filter residue and first filtrate, wherein the main components of the first filtrate are calcium chloride and magnesium chloride. For example, washing the titanium extraction slag until the soluble chloride ions are completely dissolved out can comprise soaking the titanium extraction slag raw slag in water for multiple times, washing and filtering until the content of the chloride ions in the first filter residue is less than 1 per thousand. Specifically, the raw slag of titanium slag is extracted, and soluble chloride ions in the raw slag are dissolved out by water washing and water immersion. According to the leaching condition of the chloride ions, water leaching, water washing and filtering can be adopted for multiple times until the soluble chloride ions in the filter residue are completely dissolved out (namely the content of the chloride ions in the first filter residue is less than 1 per thousand), so that a first filter residue and a first filtrate are obtained. Wherein the main components of the first filtrate are calcium chloride and magnesium chloride.

And drying the first filter residue and then grinding to obtain powder with a first particle size. The first filter residue is dried and then directly used as cement or cement concrete admixture, or used as active mineral material, or used for preparing building material by adopting alkali activator. Or grinding the first filter residue by using a ball mill to obtain fine powder. Specifically, the filter residue is dried, and at the moment, the chloride ions in the filter residue are reduced to less than 1 per thousand, so that the filter residue is not deliquesced and hygroscopic in the air. The obtained first filter residue can be directly used for the sale of cement and concrete admixture or can be used as an active mineral material to prepare building material by alkali excitation. Or grinding the first filter residue by using a ball mill to obtain fine powder with the fineness of 200-600 meshes.

And continuously washing the powder with the first particle size to reduce the content of chloride ions to below two ten-thousandth, and filtering to obtain second filter residue and second filtrate. Specifically, the ball-milled filter residue is continuously soaked in water and washed with water, and filtered to obtain a second filter residue and a second filtrate. Wherein, the content of chloride ions in the second filtrate is generally not more than 50ppm and can be directly discharged; the content of chloride ions in the second filter residue can be further reduced to less than two ten-thousandth, and the requirements of reinforced concrete and prestressed concrete on the content of the chloride ions are completely met.

And drying and mechanically activating the second filter residue to obtain powder with a second particle size, wherein the powder with the second particle size can be used as an auxiliary cementing material. Here, the content of chloride ions in the second powder may be two parts per million or less, SO₃The content can be less than 0.6 percent, the ignition loss can be less than or equal to 2.5 percent, and the specific surface area can be more than or equal to 500m²In terms of/kg. The mechanical activation device may be a jet mill or a Raymond mill. Specifically, the second filter residue is dried by waste heat generated by low-temperature chlorination of the titanium-containing slag, and is mechanically activated by a jet mill or a Raymond mill, so that the second filter residue reaches about 2000 meshes or finer, and the slag-like micro powder with the strength of s105 grade or above can be obtained. In these types of fine slag powders, the content of chloride ions, SO, is two parts per million or less₃Less than 0.6 percent, the ignition loss is less than or equal to 2.5 percent, and the specific surface area is more than or equal to 500m²The cement can be used for assembly buildings, pipe piles, high-speed rail plates, ultrahigh-strength bridges, paint additives, diatom oozes and the like, can improve the early strength of cement and concrete, improve the easiness of concrete mixing, improve the early strength and reduce hydration heat, and can also be prepared into clinker-free cement or alkali-activated cement together with an alkali activator.

In the present exemplary embodiment, the method may further include the steps of:

and evaporating and concentrating the first filtrate by utilizing the waste heat generated in the low-temperature chlorination stage of the titanium-containing blast furnace slag to obtain a first filtrate concentrate. The temperature of the evaporation and concentration of the first filtrate can be 60-120 ℃, and the concentration of the concentrated solution of the first filtrate is more than 80% of the saturated concentration of the calcium chloride solution. For example, the first filtrate concentrate may be a saturated calcium chloride solution. And adding sodium hydroxide or aluminum chloride solution into the concentrated solution of the first filtrate to completely precipitate magnesium ions and aluminum ions in the concentrated solution of the first filtrate to generate magnesium hydroxide and aluminum hydroxide, washing and filtering to obtain third filter residue and third filtrate. Here, the concentrations of the sodium hydroxide and aluminum hydroxide solutions are not limited, and the addition amounts (moles) are 2 times the molar concentration of magnesium ions and 3 times the molar concentration of aluminum ions per liter of the first filtrate concentrate. In view of economy and simple preparation process, the concentration of the sodium hydroxide is preferably 1-2 times of the concentration of the chloride ions in the first filtrate. The concentration has the advantages that sufficient solvent is provided for the reaction system, the solution volume after the reaction is not too large, and the workload of subsequent filtration and filtrate treatment is reduced.

Adding a sodium carbonate solution to the third filtrate to make Ca in the third filtrate²⁺And completely precipitating to generate calcium carbonate, and filtering to obtain a fourth filtrate and a fourth filter residue. The main component of the fourth filter residue is calcium carbonate superfine powder close to nanometer level, and the main component of the fourth filtrate is sodium chloride. Specifically, an appropriate amount of sodium carbonate solution is added to the third filtrate in such a manner that the concentration of the sodium carbonate solution is adjusted to Ca in the solution²⁺And (3) completely precipitating to generate calcium carbonate, filtering to obtain a fourth filtrate and a fourth filter residue, wherein the fourth filter residue is mainly calcium carbonate superfine powder close to the nanometer level and can be used for rubber filler and other products, and the fourth filtrate is mainly sodium chloride solution.

And evaporating and concentrating the fourth filtrate by utilizing waste heat generated by low-temperature chlorination of the titanium-containing slag to obtain a fourth filtrate concentrate. The evaporation concentration temperature of the fourth filtrate can be 80-160 ℃, and the concentration of the fourth filtrate concentrate is more than 80% of the saturated concentration of the sodium chloride solution. For example, the fourth filtrate concentrate may be a saturated sodium chloride solution.

And electrolyzing the fourth filtrate concentrated solution to respectively obtain hydrogen, chlorine and a sodium hydroxide solution, wherein the chlorine is circulated to the low-temperature chlorination stage of the titanium-containing slag to be used as a chlorine raw material. Specifically, the fourth filtrate concentrate (i.e. saturated salt solution) is electrolyzed by an electrolysis method to obtain pure H₂、Cl₂And NaOH solution, all three substances are industrial commodities and can be sold separately. Chlorine can also be used as chlorine raw material for low-temperature chlorination of titanium-containing slag, thereby realizing the circulation of chlorine element, and the sodium hydroxide solution can be evaporated to obtain a solid sodium hydroxide product.

In this embodiment, the method may further include the steps of:

and dissolving the third filter residue with sodium hydroxide, and filtering to obtain a fifth filter residue and a fifth filtrate, wherein the main component of the fifth filter residue is magnesium hydroxide, and the main component of the fifth filtrate is sodium metaaluminate.

The first filter residue can be directly used for cement or cement concrete admixture after being dried by utilizing waste heat generated in the low-temperature chlorination stage of the titanium-containing blast furnace slag, and can also be used for preparing concrete auxiliary cementing material after being ground, so that the economic benefit is improved.

The fifth filter residue mainly comprises magnesium hydroxide, and the fifth filtrate mainly comprises sodium metaaluminate solution.

And roasting the fifth filter residue at different temperatures to obtain light calcined magnesia or a light magnesia product. The fifth filter residue can be directly sold as an industrial product, and can also be roasted at different temperatures, and light-burned magnesia or light magnesia products can be obtained according to roasting temperature and time. For example, roasting the fifth filter residue at 400-600 ℃ for 30-90 min to obtain light-burned magnesium oxide; and roasting the fifth filter residue at 700-1300 ℃ for 10-60 min to obtain the light magnesium oxide.

In the exemplary embodiment, the first powder may have a particle size of 200 to 600 mesh, and the second powder may have a particle size of 1000 to 2500 mesh.

In a second exemplary embodiment of the present invention, the supplementary cementitious material may be produced by the method described in the first exemplary embodiment above. Here, the content of chloride ions in the supplementary cementitious material may be two parts per million or less, SO₃The content can be less than 0.6 percent, the ignition loss can be less than or equal to 2.5 percent, and the specific surface area can be more than or equal to 500m²The cement/kg can be used for assembly buildings, tubular piles, high-speed rail plates, ultrahigh-strength bridges, paint additives, diatom oozes and the like, can improve the early strength of cement and concrete, improve the easiness of concrete mixing, improve the early strength and reduce the hydration heat, and can also be prepared into clinker-free cement or alkali-activated cement together with an alkali activator.

For a better understanding of the invention, the following further illustrates the inventive content in connection with specific examples 1, 2 and 3, but the inventive content is not limited to the following examples only.

Example 1

And taking 1t of extracted titanium slag raw slag, repeatedly washing with water, soaking in water and filtering until soluble chloride ions in the filter slag are completely dissolved out, and filtering to obtain first filter slag and first filtrate. Wherein the content of chloride ions in the first filter residue is 0.8 per mill, and the first filtrate mainly comprises calcium chloride and magnesium chloride solution. Here, the first filtrate may be further concentrated by heating to prepare a soil arsenic removal solution, a friedel salt, or the like.

A large amount of waste heat generated in the low-temperature chlorination process of the high-titanium slag is utilized to dry the first filter residue, the quality is not reduced until after the continuous drying is carried out for 2 hours at the drying standard of 105 ℃, the moisture content in the dried second filter residue is 0 percent, and the obvious moisture absorption and agglomeration phenomenon of the dried second filter residue in the air can not occur due to the fact that the content of chloride ions is greatly reduced.

Cooling the dried second filter residue, and ball-milling with a ball mill to make the particle size less than or equal to 200 meshes, namely the maximum particle size d of the particles_maxLess than or equal to 75 mu m to obtain powder with the first grain diameter.

And continuously soaking the powder with the first particle size in water, washing with water and filtering to obtain second filter residue and second filtrate, wherein the chlorine content in the second filter residue is 0.18 per thousand and less than 0.2 per thousand, and the chlorine content is not limited when the powder is used in any cement and cement concrete. The second filtrate contains a very small amount of calcium chloride and is continuously and circularly used as the water extract for extracting the titanium slag, so that the water source can be saved while zero emission is realized.

Continuously drying the second filter residue by using the waste heat generated in the chlorination of the high titanium slag, wherein the drying temperature is less than or equal to 120 ℃, the drying granularity is kept unchanged, and the maximum particle size d_max906kg of dried second filter residue can be obtained when the particle size is less than or equal to 75 mu m, and the dried second filter residue can be directly used as a concrete auxiliary cementing material after being cooled, and also can be stored for standby use or sold as a product after being packaged.

Example 2

And taking 5t of extracted titanium slag raw slag, repeatedly washing with water, soaking in water and filtering until soluble chloride ions in the filter slag are completely dissolved out, and filtering to obtain first filter slag and first filtrate. Wherein the content of chloride ions in the first filter residue is 0.6 per mill, and the first filtrate mainly comprises calcium chloride and magnesium chloride solution. The first filtrate can be further heated and concentrated to prepare a soil arsenic removal solution, a Friedel salt and the like.

A large amount of waste heat generated in the low-temperature chlorination process of the high-titanium slag is utilized to dry the first filter residue, the quality is not reduced until after the continuous drying is carried out for 2 hours at the drying standard of 105 ℃, the moisture content in the dried second filter residue is 0 percent, and the obvious moisture absorption and agglomeration phenomenon of the dried second filter residue in the air can not occur due to the fact that the content of chloride ions is greatly reduced.

Cooling the dried second filter residue, and ball-milling with a ball mill to make the particle size less than or equal to 200 meshes, namely the maximum particle size d of the particles_maxLess than or equal to 75 mu m to obtain powder with the first grain diameter.

And continuously soaking the powder with the first particle size in water, washing with water and filtering to obtain second filter residue and second filtrate, wherein the chlorine content in the second filter residue is 0.08 per thousand and less than 0.2 per thousand, and the chlorine content is not limited when the powder is used in any cement and cement concrete. The second filtrate contains a very small amount of calcium chloride and is continuously and circularly used as the water extract for extracting the titanium slag, so that the water source can be saved while zero emission is realized.

Continuously drying the second filter residue by using the waste heat generated in the chlorination of the high titanium slag, wherein the drying temperature is less than or equal to 120 ℃, the drying granularity is kept unchanged, and the maximum particle size d_maxLess than or equal to 75 microns, obtaining 4530kg of second filter residue after drying, carrying out ultrafine grinding on the second filter residue by adopting a jet mill to ensure that the particle size reaches more than 800 meshes, d_max≤50μm，d₅₀Obtaining second particle size powder with the diameter of 20 mu m, wherein the second particle size powder is ultrafine powder slag and has higher chemical reaction activity, and the second particle size powder reaches the activity standard of S105-grade slag, can be directly used as a concrete auxiliary cementing material, and can also be packaged and stored for later use or sold as a product.

Example 3

And taking 2t of extracted titanium slag raw slag, repeatedly washing with water, soaking in water and filtering until soluble chloride ions in the filter slag are completely dissolved out, and filtering to obtain first filter slag and first filtrate. Wherein the content of chloride ions in the first filter residue is 0.9 per mill, and the first filtrate mainly comprises calcium chloride and magnesium chloride solution. The first filtrate can be further heated and concentrated to prepare a soil arsenic removal solution, a Friedel salt and the like.

A large amount of waste heat generated in the low-temperature chlorination process of the high-titanium slag is utilized to dry the first filter residue, the quality is not reduced until after the continuous drying is carried out for 2 hours at the drying standard of 105 ℃, the moisture content in the dried second filter residue is 0 percent, and the obvious moisture absorption and agglomeration phenomenon of the dried second filter residue in the air can not occur due to the fact that the content of chloride ions is greatly reduced.

Cooling the dried second filter residue, and ball-milling with a ball mill to make the particle size less than or equal to 200 meshes, namely the maximum particle size d of the particles_maxLess than or equal to 75 mu m to obtain powder with the first grain diameter.

And continuously soaking the powder with the first particle size in water, washing with water and filtering to obtain second filter residue and second filtrate, wherein the chlorine content in the second filter residue is 0.12 per thousand and less than 0.2 per thousand, and the chlorine content is not limited when the powder is used in any cement and cement concrete. The second filtrate contains a very small amount of calcium chloride and is continuously and circularly used as the water extract for extracting the titanium slag, so that the water source can be saved while zero emission is realized.

Continuously drying the second filter residue by using the waste heat generated in the chlorination of the high titanium slag, wherein the drying temperature is less than or equal to 120 ℃, the drying granularity is kept unchanged, and the maximum particle size d_maxNot more than 75 μm to obtain 1820kg of dried second filter residue, micronizing the second filter residue with jet mill to obtain second filter residue with particle size of more than 2000 meshes, d_max≤20μm，d₅₀And obtaining second particle size powder with the particle size of 10 mu m, wherein the second particle size powder is ultrafine powder slag which has extremely high chemical reaction activity and can be used as a high-quality concrete auxiliary cementing material for preparing high-strength concrete and low-hydration-heat concrete.

In summary, the beneficial effects of the present invention can include at least one of the following:

(1) the invention solves the problem that the resource utilization of the titanium extraction slag is difficult due to high chlorine content, which restricts the bottleneck of the titanium extraction process by a chlorination method, and leaches soluble chloride ions by water leaching and water washing, thereby greatly reducing the chlorine content in the slag and being beneficial to the resource utilization of the titanium extraction slag;

(2) aiming at chloride ions in the filtrate, the filtrate is subjected to chemical reaction graded treatment and recovery, products at all levels can be used as chemical raw materials or commodities for use and sale, and three wastes are not discharged in the whole process, so that the waste is changed into valuable, industrial solid waste resources are recycled, and the economic effect, resource environmental benefit and social benefit of the titanium extraction slag are greatly improved;

(3) the method effectively relieves the economic pressure and environmental protection pressure of enterprises, correspondingly saves land, reduces pollution, realizes the recycling of solid waste resources, saves natural materials, and has positive and practical significance for assisting national infrastructure and the like.

While the present invention has been described above in connection with exemplary embodiments, it will be apparent to those of ordinary skill in the art that various modifications may be made to the above-described embodiments without departing from the spirit and scope of the claims.