Method for improving acidolysis rate of titanium slag

Abstract

The present application relates to the field of titanium slag smelting and titanium slag preparation of titanium dioxide, and particularly relates to a method for improving acidolysis rate of titanium slag. The method comprises the following steps: step S1, adding the titanium slag after smelting into a cooling device, and the temperature of the added titanium slag is T1; step S2, introducing inert gas into the cooling device to cool the titanium slag once, and the cooling rate is Q1, and the temperature of the titanium slag after the first cooling is T2; step S3, introducing inert gas into the cooling device to cool the titanium slag twice, and the cooling rate is Q2, and the temperature of the titanium slag after the second cooling is T3; step S4, introducing inert gas into the cooling device to cool the titanium slag thrice, and the cooling rate is Q3, and the temperature of the titanium slag after the third cooling is T4; step S5, spraying process water into the cooling device to cool the titanium slag, and when the titanium slag is cooled to T5, the inert gas and the water spraying are stopped, and the cooling of the titanium slag is completed.

Description

Technical Field

[0001] This invention relates to the fields of titanium slag smelting and titanium dioxide production from titanium slag, and particularly to a method for improving the acid hydrolysis rate of titanium slag. Background Technology

[0002] Titanium dioxide, the third largest inorganic chemical product after synthetic ammonia and phosphoric acid, is widely used in coatings, plastics, papermaking, and inks due to its stable physicochemical properties and good optical performance. Currently, titanium dioxide production processes are mainly divided into the sulfate process and the chloride process. Compared to the chloride process, the sulfate process has a wider availability of titanium raw materials, lower technical requirements, and can produce anatase titanium dioxide, resulting in a relatively larger share of titanium dioxide production capacity. In 2021, global sulfate titanium dioxide production capacity accounted for approximately 57% of total titanium dioxide production capacity, while in my country, sulfate titanium dioxide production capacity accounted for approximately 90% of domestic titanium dioxide production capacity.

[0003] Titanium slag, as a crucial titanium raw material for the sulfuric acid process in titanium dioxide production, is used in both domestic and international titanium dioxide sulfuric acid producers. The acidolysis rate of titanium slag is a vital economic and technical indicator for these producers, as a higher acidolysis rate leads to higher titanium dioxide yield and lower acidolysis slurry volume. Therefore, it has received widespread and significant attention from sulfuric acid process titanium dioxide producers. The acidolysis rate is primarily related to the acidolysis process and equipment conditions, as well as the phase characteristics of the titanium slag. Sulfuric acid process titanium dioxide producers and related technical departments have conducted extensive research on the equipment and process conditions for titanium slag acidolysis, resulting in significant optimization and a substantial increase in the acidolysis rate, reaching approximately 93%, where further improvement is difficult. Research in this area is limited due to a lack of phase characterization equipment in sulfuric acid process titanium dioxide production. The phase characteristics of titanium slag are mainly related to its smelting raw material, titanium concentrate, smelting process, and cooling process. These characteristics primarily include phase composition and the proportion of titanium-containing phases encapsulated by silicate phases. The main phases of titanium slag are diatomite, pyroxene, elemental iron, and rutile. Diatomite and elemental iron are relatively acid-soluble, while pyroxene is poorly acid-soluble and does not participate in the acidolysis of titanium slag. The rutile phase also does not participate in the acidolysis reaction. Therefore, the higher the proportion of pyroxene and rutile, the lower the acidolysis rate of the titanium slag. Furthermore, the higher the proportion of diatomite encapsulated by pyroxene in the titanium slag, and the smaller the contact surface area between diatomite and sulfuric acid, the lower the acidolysis rate. The proportion of pyroxene is mainly related to the titanium concentrate used as raw material in titanium slag smelting and the grade of the titanium slag. The grade of the titanium slag and the raw titanium concentrate are generally determined based on the optimal economic smelting cost and resource characteristics of the titanium slag smelting enterprise, and therefore are difficult to change. The rutile content in titanium slag is mainly affected by the cooling process. Currently, the primary cooling process is "water cooling + air cooling." First, water cooling is used to rapidly reduce the slag temperature from approximately 1800℃ to 300-400℃ by pouring water onto its surface. Then, the slag is crushed, and air is used to further cool it to room temperature. Although water rapidly cools the slag to 300-400℃, the slag remains exposed to air, and the water contains a small amount of oxygen. Therefore, some low-valence titanium in the slag inevitably oxidizes to form rutile. Summary of the Invention

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a method for improving the acid hydrolysis rate of titanium slag.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] In a first aspect, in one embodiment of the present invention, a method for improving the acid hydrolysis rate of titanium slag is provided, the method comprising the following steps:

[0007] Step S1: Add the titanium slag after smelting to the cooling device, and the temperature of the added titanium slag is T1;

[0008] Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2.

[0009] Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3.

[0010] Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4.

[0011] Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag.

[0012] As a further aspect of the present invention, the inert gas after heat exchange in steps S2, S3 and S4 is introduced into the titanium concentrate drying process as a heat source to provide heat.

[0013] As a further embodiment of the present invention, T1 is 1850~1950℃; T2 is 1450~1350℃; T3 is 650~550℃; T4 is 450~350℃; and T5 is 225~175℃.

[0014] As a further embodiment of the present invention, T1 is 1800℃; T2 is 1400℃; T3 is 600℃; T4 is 400℃; and T5 is 200℃.

[0015] As a further embodiment of the present invention, Q1 is 13.33~26.67℃ / min; Q2 is 1.67~3.33℃ / min; and Q3 is 10~20℃ / min.

[0016] As a further embodiment of the present invention, Q1 is 20℃ / min; Q2 is 2.5℃ / min; and Q3 is 15℃ / min.

[0017] As a further embodiment of the present invention, the cooling device 1 includes a device body; the device body is provided with a feeding port 11 and an air supply port 12, the feeding port 11 is located on the upper part of the device body, and the air supply port 12 is located at the bottom of the device body; an air supply pipe 13 is connected to the air supply port 12, and the air supply pipe 13 is externally connected to an inert gas source; a control valve 14 for controlling the flow rate is also provided on the air supply pipe 13; and an exhaust port 15 is also provided on the side wall of the device body.

[0018] As a further embodiment of the present invention, the exhaust port 15 is connected to the heat source input end of the titanium concentrate drying kiln 2.

[0019] As a further embodiment of the present invention, a temperature sensor 17 is also provided at the bottom of the main body of the device, and a flow meter 16 is also provided on the gas delivery pipe 13.

[0020] As a further embodiment of the present invention, the cooling device 1 also includes a control terminal 3, and the flow meter 16 and the temperature sensor 17 are both communicatively connected to the control terminal 3.

[0021] The technical solution provided by this invention has the following beneficial effects:

[0022] The present invention provides a method for improving the acid hydrolysis rate of titanium slag, comprising: step S1, adding the smelted titanium slag into a cooling device at a temperature of T1; step S2, introducing inert gas into the cooling device to cool the titanium slag once at a cooling rate of Q1, and the titanium slag temperature after the first cooling is T2; step S3, introducing inert gas into the cooling device to cool the titanium slag a second time at a cooling rate of Q2, and the titanium slag temperature after the second cooling is T3; step S4, introducing inert gas into the cooling device to cool the titanium slag a third time at a cooling rate of Q3, and the titanium slag temperature after the third cooling is T4; step S5, spraying process water into the cooling device to water cool the titanium slag, and stopping the introduction of inert gas and water spraying when the titanium slag is cooled to T5, thus completing the cooling of the titanium slag. This invention improves the acidolysis rate of titanium slag by altering its phase characteristics. Simultaneously, it fully utilizes the thermal energy of the high-temperature titanium slag after smelting, eliminating the large amounts of water vapor generated during the original water cooling process that permeate the entire workshop, thus improving the working environment for workers. This solves the technical problems of difficulty in improving the acidolysis rate of titanium slag and the unutilized thermal energy of titanium slag after smelting. Therefore, it increases the acidolysis rate of titanium slag, improves the titanium dioxide yield from titanium slag in titanium dioxide production, reduces the amount of acidolysis slurry generated, and enhances the green manufacturing level of sulfuric acid process titanium dioxide. Furthermore, it reduces the energy consumption of titanium concentrate drying, providing important technical support for the promotion and application of titanium slag in the sulfuric acid process titanium dioxide field.

[0023] These or other aspects of the invention will become more apparent from the following description of embodiments. It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a structural diagram of a cooling device according to an embodiment of the present invention.

[0026] In the diagram: 1-cooling device, 2-titanium concentrate drying kiln, 3-control terminal, 11-feeding port, 12-air inlet, 13-air pipe, 14-control valve, 15-exhaust port, 16-flow meter, 17-temperature sensor. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0029] This invention provides a method for improving the acid hydrolysis rate of titanium slag, which includes the following steps:

[0030] Step S1: Add the titanium slag after smelting to the cooling device, and the temperature of the added titanium slag is T1;

[0031] Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2.

[0032] Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3.

[0033] Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4.

[0034] Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag. The water spraying mainly serves to rapidly cool the slag and quench it, making it easier for the titanium slag to be crushed.

[0035] In this embodiment of the invention, step S5 involves spraying process water into the cooling device to water-cool the titanium slag. When the titanium slag is cooled to T5, the introduction of inert gas and water spraying are stopped, completing the cooling of the titanium slag. The process further includes:

[0036] The cooled titanium slag is crushed and then packaged.

[0037] In this embodiment of the invention, the inert gas after heat exchange in steps S2, S3 and S4 is introduced into the titanium concentrate drying process as a heat source to provide heat.

[0038] In this embodiment of the invention, T1 is 1850–1950°C; T2 is 1450–1350°C; T3 is 650–550°C; T4 is 450–350°C; and T5 is 225–175°C.

[0039] In this embodiment of the invention, Q1 is 13.33–26.67 °C / min; Q2 is 1.67–3.33 °C / min; Q3 is 10–20 °C / min; it should be noted that the cooling rate is determined by the flow rate of the inert gas.

[0040] The cooling device 1 includes a main body; the main body is provided with a feeding port 11 and an air supply port 12, the feeding port 11 is located on the upper part of the main body, and the air supply port 12 is located at the bottom of the main body; an air supply pipe 13 is connected to the air supply port 12, and the air supply pipe 13 is connected to an inert gas source; a control valve 14 for controlling the flow rate is also provided on the air supply pipe 13; an exhaust port 15 is also provided on the side wall of the main body.

[0041] The exhaust port 15 is connected to the heat source input end of the titanium concentrate drying kiln 2, so that the inert gas cooled and exchanged inside the cooling device 1 provides a heat source for the titanium concentrate drying kiln 2.

[0042] A temperature sensor 17 is also installed at the bottom of the main body of the device, and a flow meter 16 is also installed on the gas supply pipe 13. The temperature sensor 17 facilitates the monitoring of the temperature of the titanium slag, and the flow meter 16 facilitates the monitoring of the flow rate of the inert gas.

[0043] The cooling device 1 also includes a control terminal 3, and the flow meter 16 and temperature sensor 17 are both communicatively connected to the control terminal 3, which facilitates the monitoring of the operating status of the cooling device 1. The control terminal 3 can be a computer.

[0044] This invention improves the acidolysis rate of titanium slag by altering its phase characteristics. Simultaneously, it fully utilizes the thermal energy of the high-temperature titanium slag after smelting, eliminating the large amounts of water vapor generated during the original water cooling process that permeate the entire workshop, thus improving the working environment for workers. This solves the technical problems of difficulty in improving the acidolysis rate of titanium slag and the unutilized thermal energy of titanium slag after smelting. Therefore, it increases the acidolysis rate of titanium slag, improves the titanium dioxide yield from titanium slag in titanium dioxide production, reduces the amount of acidolysis slurry generated, and enhances the green manufacturing level of sulfuric acid process titanium dioxide. Furthermore, it reduces the energy consumption of titanium concentrate drying, providing important technical support for the promotion and application of titanium slag in the sulfuric acid process titanium dioxide field.

[0045] Example 1

[0046] A method for improving the acid hydrolysis rate of titanium slag includes the following steps:

[0047] Step S1: Add the titanium slag after smelting to the cooling device, and the temperature of the added titanium slag is T1;

[0048] Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2.

[0049] Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3.

[0050] Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4.

[0051] Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag. The water spraying mainly serves to rapidly cool the slag and quench it, making it easier for the titanium slag to be crushed.

[0052] In this embodiment of the invention, step S5 involves spraying process water into the cooling device to water-cool the titanium slag. When the titanium slag is cooled to T5, the introduction of inert gas and water spraying are stopped, completing the cooling of the titanium slag. The process further includes:

[0053] The cooled titanium slag is crushed and then packaged.

[0054] In this embodiment of the invention, in steps S2, S3 and S4, the inert gas after heat exchange is introduced into the titanium concentrate drying process as a heat source to provide heat.

[0055] In this embodiment of the invention, T1 is 1850℃; T2 is 1450℃; T3 is 650℃; T4 is 450℃; and T5 is 225℃.

[0056] In this embodiment of the invention, Q1 is 23℃ / min; Q2 is 2.8℃ / min; Q3 is 18℃ / min; it should be noted that the cooling rate is determined by the flow rate of the inert gas.

[0057] The cooling device 1 includes a main body; the main body is provided with a feeding port 11 and an air supply port 12, the feeding port 11 is located at the upper part of the main body, and the air supply port 12 is located at the bottom of the main body; an air supply pipe 13 is connected to the air supply port 12, and the air supply pipe 13 is connected to an inert gas source; a control valve 14 for controlling the flow rate is also provided on the air supply pipe 13; an exhaust port 15 is also provided on the side wall of the main body.

[0058] The exhaust port 15 is connected to the heat source input end of the titanium concentrate drying kiln 2, so that the inert gas cooled and exchanged inside the cooling device 1 provides a heat source for the titanium concentrate drying kiln 2.

[0059] A temperature sensor 17 is also installed at the bottom of the main body of the device, and a flow meter 16 is also installed on the gas supply pipe 13. The temperature sensor 17 facilitates the monitoring of the temperature of the titanium slag, and the flow meter 16 facilitates the monitoring of the flow rate of the inert gas.

[0060] The cooling device 1 also includes a control terminal 3, and the flow meter 16 and temperature sensor 17 are both communicatively connected to the control terminal 3, which facilitates the monitoring of the operating status of the cooling device 1. The control terminal 3 can be a computer.

[0061] Example 2

[0062] A method for improving the acid hydrolysis rate of titanium slag includes the following steps:

[0063] Step S1: Add the titanium slag after smelting to the cooling device, and the temperature of the added titanium slag is T1.

[0064] Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2.

[0065] Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3.

[0066] Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4.

[0067] Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag. The water spraying mainly serves to rapidly cool the slag and quench it, making it easier for the titanium slag to be crushed.

[0068] In this embodiment of the invention, step S5 involves spraying process water into the cooling device to water-cool the titanium slag. When the titanium slag is cooled to T5, the introduction of inert gas and water spraying are stopped, completing the cooling of the titanium slag. The process further includes:

[0069] The cooled titanium slag is crushed and then packaged.

[0070] In this embodiment of the invention, in steps S2, S3 and S4, the inert gas after heat exchange is introduced into the titanium concentrate drying process as a heat source to provide heat.

[0071] In this embodiment of the invention, T1 is 1950℃; T2 is 1350℃; T3 is 550℃; T4 is 350℃; and T5 is 175℃.

[0072] In this embodiment of the invention, Q1 is 17.5℃ / min; Q2 is 2.1℃ / min; Q3 is 13℃ / min; it should be noted that the cooling rate is determined by the flow rate of the inert gas.

[0073] The cooling device 1 includes a main body; the main body is provided with a feeding port 11 and an air supply port 12, the feeding port 11 is located at the upper part of the main body, and the air supply port 12 is located at the bottom of the main body; an air supply pipe 13 is connected to the air supply port 12, and the air supply pipe 13 is connected to an inert gas source; a control valve 14 for controlling the flow rate is also provided on the air supply pipe 13; an exhaust port 15 is also provided on the side wall of the main body.

[0074] The exhaust port 15 is connected to the heat source input end of the titanium concentrate drying kiln 2, so that the inert gas cooled and exchanged inside the cooling device 1 provides a heat source for the titanium concentrate drying kiln 2.

[0075] A temperature sensor 17 is also installed at the bottom of the main body of the device, and a flow meter 16 is also installed on the gas supply pipe 13. The temperature sensor 17 facilitates the monitoring of the temperature of the titanium slag, and the flow meter 16 facilitates the monitoring of the flow rate of the inert gas.

[0076] The cooling device 1 also includes a control terminal 3, and the flow meter 16 and temperature sensor 17 are both communicatively connected to the control terminal 3, which facilitates the monitoring of the operating status of the cooling device 1. The control terminal 3 can be a computer.

[0077] Example 3

[0078] A method for improving the acid hydrolysis rate of titanium slag includes the following steps:

[0079] Step S1: Add the titanium slag after smelting to the cooling device, and the temperature of the added titanium slag is T1.

[0080] Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2.

[0081] Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3.

[0082] Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4.

[0083] Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag. The water spraying mainly serves to rapidly cool the slag and quench it, making it easier for the titanium slag to be crushed.

[0084] In this embodiment of the invention, step S5 involves spraying process water into the cooling device to water-cool the titanium slag. When the titanium slag is cooled to T5, the introduction of inert gas and water spraying are stopped, completing the cooling of the titanium slag. The process further includes:

[0085] The cooled titanium slag is crushed and then packaged.

[0086] In this embodiment of the invention, in steps S2, S3 and S4, the inert gas after heat exchange is introduced into the titanium concentrate drying process as a heat source to provide heat.

[0087] In this embodiment of the invention, T1 is 1800℃; T2 is 1400℃; T3 is 600℃; T4 is 400℃; and T5 is 200℃.

[0088] In this embodiment of the invention, Q1 is 20℃ / min; Q2 is 2.5℃ / min; Q3 is 15℃ / min; it should be noted that the cooling rate is determined by the flow rate of the inert gas.

[0089] The cooling device 1 includes a main body; the main body is provided with a feeding port 11 and an air supply port 12, the feeding port 11 is located at the upper part of the main body, and the air supply port 12 is located at the bottom of the main body; an air supply pipe 13 is connected to the air supply port 12, and the air supply pipe 13 is connected to an inert gas source; a control valve 14 for controlling the flow rate is also provided on the air supply pipe 13; an exhaust port 15 is also provided on the side wall of the main body.

[0090] The exhaust port 15 is connected to the heat source input end of the titanium concentrate drying kiln 2, so that the inert gas cooled and exchanged inside the cooling device 1 provides a heat source for the titanium concentrate drying kiln 2.

[0091] A temperature sensor 17 is also installed at the bottom of the main body of the device, and a flow meter 16 is also installed on the gas supply pipe 13. The temperature sensor 17 facilitates the monitoring of the temperature of the titanium slag, and the flow meter 16 facilitates the monitoring of the flow rate of the inert gas.

[0092] The cooling device 1 also includes a control terminal 3, and the flow meter 16 and temperature sensor 17 are both communicatively connected to the control terminal 3, which facilitates the monitoring of the operating status of the cooling device 1. The control terminal 3 can be a computer.

[0093] Example 4

[0094] A method for improving the acid hydrolysis rate of titanium slag includes the following steps:

[0095] Step S1: Add the titanium slag after smelting to the cooling device, and the temperature of the added titanium slag is T1.

[0096] Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2.

[0097] Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3.

[0098] Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4.

[0099] Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag. The water spraying mainly serves to rapidly cool the slag and quench it, making it easier for the titanium slag to be crushed.

[0100] In this embodiment of the invention, step S5 involves spraying process water into the cooling device to water-cool the titanium slag. When the titanium slag is cooled to T5, the introduction of inert gas and water spraying are stopped, completing the cooling of the titanium slag. The process further includes:

[0101] The cooled titanium slag is crushed and then packaged.

[0102] In this embodiment of the invention, in steps S2, S3 and S4, the inert gas after heat exchange is introduced into the titanium concentrate drying process as a heat source to provide heat.

[0103] In this embodiment of the invention, T1 is 1800℃; T2 is 1400℃; T3 is 600℃; T4 is 400℃; and T5 is 200℃.

[0104] In this embodiment of the invention, Q1 is 13.33℃ / min; Q2 is 1.67℃ / min; Q3 is 10℃ / min; it should be noted that the cooling rate is determined by the flow rate of the inert gas.

[0105] The cooling device 1 includes a main body; the main body is provided with a feeding port 11 and an air supply port 12, the feeding port 11 is located at the upper part of the main body, and the air supply port 12 is located at the bottom of the main body; an air supply pipe 13 is connected to the air supply port 12, and the air supply pipe 13 is connected to an inert gas source; a control valve 14 for controlling the flow rate is also provided on the air supply pipe 13; an exhaust port 15 is also provided on the side wall of the main body.

[0106] The exhaust port 15 is connected to the heat source input end of the titanium concentrate drying kiln 2, so that the inert gas cooled and exchanged inside the cooling device 1 provides a heat source for the titanium concentrate drying kiln 2.

[0107] A temperature sensor 17 is also installed at the bottom of the main body of the device, and a flow meter 16 is also installed on the gas supply pipe 13. The temperature sensor 17 facilitates the monitoring of the temperature of the titanium slag, and the flow meter 16 facilitates the monitoring of the flow rate of the inert gas.

[0108] The cooling device 1 also includes a control terminal 3, and the flow meter 16 and temperature sensor 17 are both communicatively connected to the control terminal 3, which facilitates the monitoring of the operating status of the cooling device 1. The control terminal 3 can be a computer.

[0109] Example 5

[0110] A method for improving the acid hydrolysis rate of titanium slag includes the following steps:

[0111] Step S1: Add the titanium slag after smelting to the cooling device, and the temperature of the added titanium slag is T1.

[0112] Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2.

[0113] Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3.

[0114] Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4.

[0115] Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag. The water spraying mainly serves to rapidly cool the slag and quench it, making it easier for the titanium slag to be crushed.

[0116] In this embodiment of the invention, step S5 involves spraying process water into the cooling device to water-cool the titanium slag. When the titanium slag is cooled to T5, the introduction of inert gas and water spraying are stopped, completing the cooling of the titanium slag. The process further includes:

[0117] The cooled titanium slag is crushed and then packaged.

[0118] In this embodiment of the invention, in steps S2, S3 and S4, the inert gas after heat exchange is introduced into the titanium concentrate drying process as a heat source to provide heat.

[0119] In this embodiment of the invention, T1 is 1800℃; T2 is 1400℃; T3 is 600℃; T4 is 400℃; and T5 is 200℃.

[0120] In this embodiment of the invention, Q1 is 26.67℃ / min; Q2 is 3.33℃ / min; Q3 is 20℃ / min; it should be noted that the cooling rate is determined by the flow rate of the inert gas.

[0121] The cooling device 1 includes a main body; the main body is provided with a feeding port 11 and an air supply port 12, the feeding port 11 is located at the upper part of the main body, and the air supply port 12 is located at the bottom of the main body; an air supply pipe 13 is connected to the air supply port 12, and the air supply pipe 13 is connected to an inert gas source; a control valve 14 for controlling the flow rate is also provided on the air supply pipe 13; an exhaust port 15 is also provided on the side wall of the main body.

[0122] The exhaust port 15 is connected to the heat source input end of the titanium concentrate drying kiln 2, so that the inert gas cooled and exchanged inside the cooling device 1 provides a heat source for the titanium concentrate drying kiln 2.

[0123] A temperature sensor 17 is also installed at the bottom of the main body of the device, and a flow meter 16 is also installed on the gas supply pipe 13. The temperature sensor 17 facilitates the monitoring of the temperature of the titanium slag, and the flow meter 16 facilitates the monitoring of the flow rate of the inert gas.

[0124] The cooling device 1 also includes a control terminal 3, and the flow meter 16 and temperature sensor 17 are both communicatively connected to the control terminal 3, which facilitates the monitoring of the operating status of the cooling device 1. The control terminal 3 can be a computer.

[0125] Comparative Example 1

[0126] Titanium slag is cooled using a traditional cooling slag basin (the slag cooling basin is open with no lid on the top and has a horizontal structure at the bottom) and water cooling process. That is, after the titanium slag is taken out of the smelting furnace, it is immediately cooled with a large amount of process water until the temperature of the titanium slag drops to 400°C. Then, water cooling is stopped, and the slag is crushed and packaged.

[0127] Performance testing

[0128] The rutile content and the proportion of pyroxene-encapsulated black titanium dioxide in the titanium slag of Examples 2, 3, 4, and Comparative Example 1 were detected by XRD and MLA, respectively. The titanium slag from Examples 2, 3, 4, and Comparative Example 1 were sent to a titanium dioxide production plant using the sulfuric acid process. The plant performed acidolysis according to the following conditions: acid-to-slag ratio of 1.7, acid concentration of 91%, and aging time of 2 hours. The maximum temperature of the acidolysis reaction was monitored. After acidolysis, the acidolysis rate and the amount of acidolysis slurry per ton of titanium dioxide were measured. The comparative results of the experiments in Examples 2, 3, 4, and Comparative Example 1 are shown in Table 1.

[0129] Table 1 Performance test results of Examples 2, 3, 4 and Comparative Example 1

[0130]

[0131] As can be seen from the results of the examples, compared with Comparative Example 1 and Examples 2, 3, and 4, the present invention, compared with the traditional method, reduces the rutile content in titanium slag from 1.2% to 0.0%, the proportion of black titanium ore encapsulated by pyroxene in titanium slag from 1.5% to about 0.3%, increases the maximum temperature of titanium slag acidolysis reaction by about 10°C, increases the titanium slag acidolysis rate by about 5.0%, and reduces the amount of acidolysis slurry per ton of titanium dioxide by about 50 kg. The experimental results show that this technology can significantly avoid the formation of rutile during the cooling process of titanium slag, improve the crystallinity of pyroxene, reduce the proportion of black titanium ore encapsulated by pyroxene in titanium slag, thereby increasing the titanium slag acidolysis rate and reducing the amount of acidolysis slurry after titanium slag acidolysis.

[0132] This invention uses an "inert gas cooling + water cooling + air cooling" method to cool the smelted titanium slag. After heat exchange, the high-temperature inert gas is reused in the drying process of titanium concentrate, the raw material for titanium slag smelting, so as to serve as a heat source for drying titanium concentrate and reduce the energy consumption required for drying titanium concentrate.

[0133] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for improving the acid hydrolysis rate of titanium slag, characterized in that, The method includes: step S1, adding the titanium slag after smelting to a cooling device, and the temperature of the added titanium slag is T1; Step S2: Inert gas is introduced into the cooling device to cool the titanium slag once, and the cooling rate is Q1. After the first cooling is completed, the temperature of the titanium slag is T2. Step S3: Inert gas is introduced into the cooling device to perform secondary cooling on the titanium slag, and the cooling rate is Q2. After the secondary cooling is completed, the temperature of the titanium slag is T3. Step S4: Inert gas is introduced into the cooling device to cool the titanium slag three times, with a cooling rate of Q3, and the temperature of the titanium slag after the three coolings is T4. Step S5: Spray process water into the cooling device to cool the titanium slag. When the titanium slag is cooled to T5, stop the introduction of inert gas and water spraying to complete the cooling of the titanium slag. Among them, T1 is 1850~1950℃; T2 is 1450~1350℃; T3 is 650~550℃; T4 is 450~350℃; T5 is 225~175℃; Q1 is 13.33~26.67℃ / min; Q2 is 1.67~3.33℃ / min; Q3 is 10~20℃ / min.

2. The method for improving the acid hydrolysis rate of titanium slag as described in claim 1, characterized in that, The inert gas after heat exchange in steps S2, S3 and S4 is introduced into the titanium concentrate drying process as a heat source to provide heat.

3. The method for improving the acid hydrolysis rate of titanium slag as described in claim 1, characterized in that, Q1 is 20℃ / min; Q2 is 2.5℃ / min; Q3 is 15℃ / min.

4. The method for improving the acid hydrolysis rate of titanium slag as described in any one of claims 1-3, characterized in that, The cooling device includes a main body; the main body is provided with a feeding port and an air supply port, the feeding port is located at the upper part of the main body, and the air supply port is located at the bottom of the main body; an air supply pipe is connected to the air supply port, and an inert gas source is connected to the air supply pipe; a control valve for controlling the flow rate is also provided on the air supply pipe; an exhaust port is also provided on the side wall of the main body.

5. The method for improving the acid hydrolysis rate of titanium slag as described in claim 4, characterized in that, The exhaust port is connected to the heat source input end of the titanium concentrate drying kiln.

6. The method for improving the acid hydrolysis rate of titanium slag as described in claim 4, characterized in that, A temperature sensor is also installed at the bottom of the main body of the device, and a flow meter is also installed on the gas pipeline.

7. The method for improving the acid hydrolysis rate of titanium slag as described in claim 6, characterized in that, The cooling device also includes a control terminal, and the flow meter and temperature sensor are both communicatively connected to the control terminal.

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