CN101988158A - Comprehensive utilization method of titanium-containing waste residues - Google Patents

Abstract

The present invention relates to the field of environmental protection technology, in particular to a method for comprehensive utilization of titanium-containing waste residue, which is carried out according to the following steps: the technical solution for realizing the purpose of the present invention is carried out according to the following steps: (1) crushing and grinding: the titanium-containing waste residue is crushed and Grinding to obtain a powder with a diameter of 50-160 μm; (2) material mixing: mix the titanium-containing waste slag powder with ammonium sulfate, and then mix it with potassium sulfate evenly; (3) melting: heat the above-mentioned mixed material to 200-500 ° C and Insulate for 1 to 50 minutes to obtain massive solids and ammonia gas; (4) Dissolving and filtering: dissolve the above massive solids in water and filter to obtain filtrate and residues, which are used as cement additives; (5) precipitation of titanium; (6) precipitation of aluminum. The invention has wide sources of raw materials, solves the problem of environmental pollution caused by massive discharge of titanium-containing waste residues, and rationally utilizes resources such as titanium and aluminum, and has considerable environmental, social and economic benefits.

Description

A comprehensive utilization method of titanium-containing waste slag

technical field

The invention relates to the technical field of environmental protection, in particular to a comprehensive utilization method of titanium-containing waste residue.

Background technique

The discharge of titanium-containing waste slag (including titanium-containing tailings and titanium-containing blast furnace slag) has caused the loss of a large amount of titanium resources and polluted the environment. Therefore, its utilization has become the focus of attention. Titanium-containing waste slag cannot be directly used in cement production, thus limiting its use. Since the end of the 1960s, Chongqing University and Panzhihua Iron and Steel Research Institute have used ferrosilicon containing 75% silicon as a reducing agent to produce silicon-titanium ferroalloy, which is used to replace ferro-titanium to produce low-titanium alloy steel. At the end of the 1980s, the experimental research on the preparation of TiCl ₄ from titanium-containing waste slag was completed. Northeastern University enriches the titanium components dispersed in multiple phases into one phase (perovskite) as much as possible; then properly controls the cooling rate to promote the growth and coarsening of the phase enriched with titanium components to meet the particle size requirement of mineral separation (>40μm), and finally separated by mineral processing method, that is, selective enrichment, growth and separation, and the perovskite with a grade of 35% to 40% is selected. In addition, there are also reports on the preparation of glazed tiles and Sialon ceramic materials from titanium-containing waste residues. In these studies, the overall utilization of waste slag did not fully consider the utilization of titanium resources in slag, and the research process for partial utilization or for the purpose of extracting _TiO2 is complicated, and the utilization rate of titanium resources is generally only 65% to 85%. waste and new pollution. In addition, there is no report on recovering alumina from titanium-containing waste slag. Therefore, the development of a new process with simple process, low cost, large demand for products, high utilization rate of titanium and other resources, little environmental pollution, elimination of environmental pollution from titanium-containing waste slag, and large-scale utilization of it is an urgent need to solve The problem.

The technology with the patent application number 200810011305.7 utilizes raw materials such as titanium-containing blast furnace slag and ammonium sulfate to prepare plant fertilizers, but the process has the following disadvantages: (1) The dissolution rate of titanium in titanium-containing blast furnace slag is 82%, and 18% of the titanium is still unusable , resulting in the loss of titanium resources; (2) ammonia volatilization during the process will cause serious air pollution and operator poisoning, etc. If consideration is given to recycling ammonia, it will greatly increase the complexity and cost of the process; (3) high titanium content The aluminum in the slag cannot be recycled, resulting in the loss of aluminum resources; (4) the added value of the product is low, and the economic benefit is not high.

The technology with patent application number 200810229589.7 provides a method for preparing potassium nitrogen sulfur magnesium titanium ferrosilicon foliar fertilizer and calcium sulfur silicon fertilizer with titanium-containing blast furnace slag. In addition to the above four shortcomings, this process also has this problem: Part of CaTiO3 in titanium-containing blast furnace slag exists as an impurity in the remaining residue after titanium extraction. Because of the large content of CaTiO3 and strong crystallization ability, it cannot be used as a cement additive, but can only be used as calcium sulfur silicon fertilizer.

Contents of the invention

The object of the present invention is to provide a comprehensive utilization method of titanium-containing waste slag to solve the problem of environmental pollution and make full use of titanium and aluminum resources at the same time.

The technical scheme that realizes the object of the present invention is to carry out as follows:

(1) Crushing and grinding: The titanium-containing waste residue is crushed and ground to obtain a powder with a diameter of 50-160 μm;

(2) Mixing: Mix the titanium-containing waste residue powder with ammonium sulfate, and then mix it with potassium sulfate evenly. The material is mixed to obtain titanium-containing waste residue powder by weight percentage: ammonium sulfate: potassium sulfate=1:3～14:1～8;

(3) Melting: heat up the above-mentioned mixed material to 200-500°C and keep it warm for 1-50 minutes to obtain massive solid and ammonia gas;

(4) Dissolving and filtering: dissolving the above-mentioned blocky solid in water, then filtering to obtain filtrate and residue, and the residue is used as cement additive;

(5) Precipitation of titanium: pass the ammonia gas obtained in step (3) into the above-mentioned filtrate, and control the pH to 1.8-3.5, so that the titanium in the filtrate is precipitated and separated, and titanium dioxide and mother liquor 1 are obtained;

(6) Precipitation of aluminum: pass the ammonia gas obtained in step (3) into the mother liquor 1, and control the pH to 5.8-7.5, so that the aluminum in the mother liquor 1 can be precipitated and separated to obtain alumina and the mother liquor 2; the mother liquor 2 is heated and evaporated Dry to obtain a mixture containing ammonium sulfate and potassium sulfate, which is recycled to step (2) for reuse.

The weight percentage of titanium dioxide in the titanium-containing waste slag is 4%-36%.

In the filtrate of the step (4), the percentage of water-soluble titanium to the total weight of titanium in the titanium-containing waste slag is ≥97.1%, and the percentage of water-soluble aluminum to the total weight of aluminum in the titanium-containing waste slag is ≥97.2%.

The titanium precipitated in the form of titanium dioxide in the step (5) accounts for more than 95.4% of the total weight of titanium in the filtrate.

The aluminum precipitated in the form of alumina in the step (6) accounts for ≥98.0% of the total weight of aluminum in the mother liquor 1.

The weight purity of the titanium dioxide product is ≥99%, and the particle size is nanoscale; the cement additive consists of 65.8wt% to 69.3wt% of calcium sulfate, 30wt% to 33wt% of calcium silicate and 0.3 to 1.2wt% of calcium silicate Titanium dioxide.

Compared with prior art, feature of the present invention and beneficial effect thereof are:

The raw material potassium sulfate selected in the present invention has active chemical properties under heating conditions, can penetrate the mineral lattice, undergo a melting reaction with titanium-containing waste residue, and have a synergistic effect with ammonium sulfate to promote the decomposition of titanium-containing waste residue, shorten the reaction time and increase the concentration of titanium dioxide. The dissolution rate of the invention makes it reach more than 97%, which completely solves the problem of loss of titanium resources, and at the same time recovers aluminum resources from the titanium-containing waste residue; in addition, the content of titanium dioxide in the product cement additive of the present invention is less than 3%, according to the national standard , can be used in the production of cement, which cannot be realized by the prior art.

It is generally believed that the lower the percentage of valuable components in mineral raw materials, the more difficult it is to process. Therefore, the treatment process for titanium-containing waste residues with a weight percentage of 4% to 13% of titanium dioxide, such as titanium-containing tailings, has always been a blank in research. The present invention handles titanium-containing tailings very well, which is a significant technical progress. .

In summary, the present invention has a wide range of sources of raw materials, one-time overall utilization of titanium-containing waste residue, and the recycling of intermediate products, reducing the consumption of raw materials and water, no secondary pollution, simple process, low cost, and high added value of products , high economic benefit. It not only solves the problem of environmental pollution caused by a large amount of titanium-containing waste residue, but also rationally utilizes resources such as titanium and aluminum, and completely solves the problem of loss of resources such as titanium and aluminum, and the method of the invention is easy to realize industrial production and has considerable environmental protection. benefit, social benefit and economic benefit.

Description of drawings

Fig. 1 is a block diagram of the process flow of the comprehensive utilization method of titanium-containing waste slag.

Fig. 2 is an XRD pattern of titanium dioxide prepared in the present invention.

Detailed ways

The present invention will be described in detail below in conjunction with the examples, but the protection scope of the present invention is not limited to the following examples.

Example 1:

(1) Crushing and grinding: the titanium-containing waste residue containing 4% by weight of titanium dioxide is crushed and ground to obtain a powder with a diameter of 50 μm;

(2) Mixing: According to the weight ratio of titanium-containing waste residue powder: ammonium sulfate: potassium sulfate=1:4:8, weigh the raw materials, mix the titanium-containing waste residue powder with ammonium sulfate, and then mix it with potassium sulfate evenly;

(3) Melting: raise the temperature of the above mixed material to 370°C and keep it warm for 50 minutes to obtain massive solid and ammonia gas;

(4) Dissolving and filtering: Dissolve the above massive solid in water, then filter to obtain the filtrate and residue, the water-soluble titanium in the filtrate accounts for 97.1% of the total weight of titanium in the titanium-containing waste residue, and the water-soluble aluminum accounts for 97.1% of the total weight of titanium in the titanium-containing waste residue. The percentage of the total weight of aluminum is 97.2%, and the residue is used as a cement additive;

(5) Precipitation of titanium: pass the ammonia gas obtained in step (3) into the above filtrate, and control the pH to 2.1, so that the titanium in the filtrate is precipitated to generate titanium dioxide and mother liquor 1, and the titanium precipitated in the form of titanium dioxide accounts for the titanium in the filtrate The percentage of total weight is 95.4%;

(6) Precipitation of aluminum: pass the ammonia gas obtained in step (3) into the mother liquor 1, and control the pH to 7.5, so that the aluminum in the mother liquor 1 is precipitated to form alumina and mother liquor 2, and the aluminum precipitated in the form of alumina accounts for the filtrate The percentage of the total weight of aluminum in the mixture is 99%; the mother liquor 2 is heated and evaporated to dryness to obtain a mixture containing ammonium sulfate and potassium sulfate, which is recycled to step (2) for reuse.

The titanium dioxide product has a weight purity of 99.2% and a particle size of 25nm; the cement additive consists of 68wt% calcium sulfate, 31.7wt% calcium silicate and 0.3wt% titanium dioxide.

Example 2:

(1) Crushing and grinding: the titanium-containing waste residue containing 33% by weight of titanium dioxide is crushed and ground to obtain a powder with a diameter of 150 μm;

(2) Material mixing: according to the weight ratio of titanium-containing waste residue powder: ammonium sulfate: potassium sulfate=1:12:5, weigh the raw materials, mix the titanium-containing waste residue powder with ammonium sulfate, and then mix with potassium sulfate evenly;

(3) Melting: raise the temperature of the above-mentioned mixed material to 480°C and keep it warm for 3 minutes to obtain massive solid and ammonia gas;

(4) Dissolving and filtering: Dissolve the above massive solid in water, and then filter to obtain the filtrate and residue. The water-soluble titanium in the filtrate accounts for 98.9% of the total weight of titanium in the titanium-containing waste residue, and the water-soluble aluminum accounts for 98.9% of the total weight of titanium in the titanium-containing waste residue. The percentage of the total weight of aluminum is 98.6%, and the residue is used as a cement additive;

(5) Precipitation of titanium: pass the ammonia gas obtained in step (3) into the above-mentioned filtrate, and control the pH to 3.3, so that the titanium in the filtrate is precipitated to generate titanium dioxide and mother liquor 1, and the titanium precipitated in the form of titanium dioxide accounts for the titanium in the filtrate The percentage of total weight is 99.1%;

(6) Precipitation of aluminum: pass the ammonia gas obtained in step (3) into the mother liquor 1, and control the pH to 6.9, so that the aluminum in the mother liquor 1 is precipitated to form alumina and mother liquor 2, and the aluminum precipitated in the form of alumina accounts for the filtrate The percentage of the total weight of aluminum in the mixture is 98.3%; the mother liquor 2 is heated and evaporated to dryness to obtain a mixture containing ammonium sulfate and potassium sulfate, which is recycled to step (2) for reuse.

The titanium dioxide product has a weight purity of 99.4% and a particle size of 50nm; the cement additive consists of 69.3wt% calcium sulfate, 30wt% calcium silicate and 0.7wt% titanium dioxide.

Example 3:

(1) Crushing and grinding: the titanium-containing waste residue containing 21% by weight of titanium dioxide is crushed and ground to obtain a powder with a diameter of 95 μm;

(2) Weigh the raw materials according to the weight ratio of titanium-containing waste residue powder: ammonium sulfate: potassium sulfate = 1:9:2, mix the titanium-containing waste residue powder with ammonium sulfate, and then mix with potassium sulfate evenly;

(3) Melting: raise the temperature of the above mixed material to 240°C and keep it warm for 32 minutes to obtain massive solid and ammonia gas;

(4) Dissolving and filtering: Dissolve the above massive solid in water, and then filter to obtain the filtrate and residue. The water-soluble titanium in the filtrate accounts for 97.5% of the total weight of titanium in the titanium-containing waste residue, and the water-soluble aluminum accounts for 97.5% of the total weight of titanium in the titanium-containing waste residue. The percentage of the total weight of aluminum is 97.8%, and the residue is used as a cement additive;

(5) Precipitation of titanium: pass the ammonia gas obtained in step (3) into the above-mentioned filtrate, and control the pH to 2.6, so that the titanium in the filtrate is precipitated to generate titanium dioxide and mother liquor 1, and the titanium precipitated in the form of titanium dioxide accounts for the titanium in the filtrate The percentage of total weight is 98.7%;

(6) Precipitation of aluminum: pass the ammonia gas obtained in step (3) into the mother liquor 1, and control the pH to 6.2, so that the aluminum in the mother liquor 1 is precipitated to form alumina and mother liquor 2, and the aluminum precipitated in the form of alumina accounts for the filtrate The percentage of the total weight of aluminum in the mixture is 98.1%; the mother liquor 2 is heated and evaporated to dryness to obtain a mixture containing ammonium sulfate and potassium sulfate, which is recycled to step (2) for reuse.

The titanium dioxide product has a weight purity of 99.3% and a particle size of 70nm; the cement additive consists of 65.8wt% calcium sulfate, 33wt% calcium silicate and 1.2wt% titanium dioxide.

Claims (6)

1. the method for comprehensive utilization of a titaniferous waste residue is characterized in that carrying out according to the following steps:

⑴ fragmentation and grinding: the powder that the titaniferous waste residue is obtained diameter 50～160 μ m through broken and grinding;

⑵ batch mixing: titaniferous waste residue powder is mixed with ammonium sulfate, and then mix with vitriolate of tartar, mixing of materials is titaniferous waste residue powder by weight percentage: ammonium sulfate: vitriolate of tartar=1:3～14:1～8;

⑶ fusion: the material of above-mentioned mixing is warming up to 200～500 ℃ and be incubated 1～50min, obtains blocks of solid and ammonia;

⑷ dissolving and filtration: place water to dissolve the above-mentioned blocks of solid that obtains, filter then and obtain filtrate and residue, residue is as cement additire;

⑸ the precipitation of titanium: in above-mentioned filtrate, feed the ammonia that step (3) obtains, and control pH is 1.8～3.5, makes titanium precipitation in the filtrate, separate, obtain titanium dioxide and mother liquor 1;

⑹ the precipitation of aluminium: in mother liquor 1, feed the ammonia that step (3) obtains, and control pH be 5.8～7.5, make aluminum precipitation, separation in the mother liquor 1, obtain aluminum oxide and mother liquor 2; With mother liquor 2 heating evaporates to dryness, obtain the mixture of sulfur acid ammonium and vitriolate of tartar, this mixture is recycled to step ⑵ and utilizes.

2. the method for comprehensive utilization of a kind of titaniferous waste residue according to claim 1, the weight percentage that it is characterized in that titanium dioxide in the described titaniferous waste residue is 4%～36%.

3. the method for comprehensive utilization of a kind of titaniferous waste residue according to claim 1, it is characterized in that in the filtrate of described step (4), water-soluble titanium accounts for per-cent 〉=97.1% of the gross weight of titanium in the titaniferous waste residue, and water-soluble aluminum accounts for per-cent 〉=97.2% of the gross weight of aluminium in the titaniferous waste residue.

4. the method for comprehensive utilization of a kind of titaniferous waste residue according to claim 1 is characterized in that accounting for the sedimentary titanium of titanium dioxide form in the described step (5) percentage 〉=95.4% of titanium gross weight in the filtrate.

5. the method for comprehensive utilization of a kind of titaniferous waste residue according to claim 1 is characterized in that accounting for the sedimentary aluminium of aluminum oxide form in the described step (6) per-cent 〉=98.0% of aluminium gross weight in the mother liquor 1.

6. the method for comprehensive utilization of a kind of titaniferous waste residue according to claim 1 is characterized in that described product titanium dioxide weight purity 〉=99%, and granularity is a nano level; The composition of cement additire is that the calcium sulfate of 65.8wt%～69.3wt%, Calucium Silicate powder and the content of 30wt%～33wt% are the titanium dioxide of 0.3～1.2wt%.

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