Rotary kiln material cooling device for preparing titanium dioxide by sulfuric acid method

Abstract

The utility model discloses a rotary kiln material cooling device for preparing titanium dioxide by a sulfuric acid method, and relates to the technical field of rotary kiln material cooling. Comprising a conveyor, the top of one side of the conveyor is fixedly communicated with a rotary kiln discharge pipe, and the bottom of the other side of the conveyor is fixedly communicated with a conveyor discharge pipe; the conveyor comprises a conveying shell and a rotating shaft, a motor is fixed to the side face of the conveying shell, the output end of the motor is fixed to the end of the rotating shaft, a first spiral blade is fixed to a shaft body, close to the rotary kiln discharging pipe, of the rotating shaft, and a second spiral blade is fixed to a shaft body, away from the rotary kiln discharging pipe, of the rotating shaft. According to the cooling device, the air cooling assembly and the water cooling assembly are arranged on the outer side of the conveyor, and the water cooling assembly is arranged on the outer side of the air cooling assembly, so that the occupied area of the cooling device is reduced while materials are cooled.

Description

Technical Field

[0001] This utility model relates to the field of rotary kiln material cooling technology, specifically a rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process. Background Technology

[0002] In the sulfuric acid process for titanium dioxide production, the temperature of the material after calcination in a rotary kiln is as high as 800-1000℃. It needs to be rapidly cooled to below 100℃ for subsequent crushing and packaging. Traditional cooling methods mostly use single-stage water cooling or direct air cooling.

[0003] Chinese utility model patent, authorized announcement number CN219368336U, discloses a material cooling device for rotary kilns used in the production of sulfuric acid titanium dioxide. By using an air-cooled cooler and a water-cooled cooler in series, the material temperature of high-capacity rotary kilns can be reduced more efficiently, achieving energy saving and consumption reduction, and also helping to reduce the space occupied by the cooling device.

[0004] The above solution solves the technical problems mentioned in the background art. However, in practical applications, the above solution still has certain defects. For example, the above device connects air cooling and water cooling in series to cool the material, which increases the space occupied by the cooling device, which is disadvantageous for places with limited space. Utility Model Content

[0005] The purpose of this invention is to provide a rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process, comprising a conveyor, wherein a rotary kiln discharge pipe is fixedly connected to the top of one side of the conveyor, and a conveyor discharge pipe is fixedly connected to the bottom of the other side.

[0007] The conveyor includes a conveying housing and a rotating shaft. A motor is fixed to the side of the conveying housing. The output end of the motor is fixed to the end of the rotating shaft. A first spiral blade is fixed on the shaft near the rotary kiln discharge pipe, and a second spiral blade is fixed on the shaft away from the rotary kiln discharge pipe. The inclination angle of the first spiral blade is greater than that of the second spiral blade.

[0008] A cooling mechanism is provided on the outside of the conveyor housing.

[0009] Preferably, the cooling mechanism includes a cavity formed on the conveying housing, with a hot gas outlet pipe fixedly connected to the side of the cavity near the rotary kiln discharge pipe, and a cold gas inlet pipe fixedly connected to the side of the cavity away from the rotary kiln discharge pipe, and the cold gas inlet pipe fixedly connected to the air outlet of the air-cooled cooler.

[0010] An outer shell is fixed to the outside of the conveying housing, and a gap is formed between the outer shell and the conveying housing. A cold water outlet pipe is fixedly connected to the side of the outer shell near the rotary kiln discharge pipe, and a hot water outlet pipe is fixedly connected to the side of the outer shell away from the rotary kiln discharge pipe. The cold water outlet pipe is fixedly connected to the outlet of the water-cooled cooler.

[0011] Preferably, the cavity is provided with a plurality of equally spaced gas dispersants, and the cooling gas is evenly distributed in the cavity through the gas dispersants.

[0012] Preferably, the gas dispersion component includes an annular plate, and the annular plate has a plurality of inclined holes arranged in a circumferential array on its plate body.

[0013] Preferably, a spiral plate is fixed within the gap.

[0014] Preferably, a temperature sensor is fixed to the inner wall of the conveyor discharge pipe.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] The rotary kiln material cooling device for the sulfuric acid process titanium dioxide production has an air-cooled component and a water-cooled component installed outside the conveyor, with the water-cooled component located outside the air-cooled component. This achieves material cooling while reducing the footprint of the cooling device.

[0017] Meanwhile, a conveyor is installed, which turns the material over by a spiral guide plate, so that the material is cooled evenly and the product quality is improved.

[0018] In addition, a gas dispersion component is installed inside the cavity. First, the cold air is injected at a certain angle, generating vortices, which prolongs the residence time of the gas in the cavity and improves the cooling efficiency. Second, the inclined hole can adjust the airflow resistance, balance the pressure distribution inside the cavity, and reduce energy loss caused by turbulence. Attached Figure Description

[0019] Figure 1 This is a connection diagram of the present invention;

[0020] Figure 2 This is a half-sectional view of the present invention;

[0021] Figure 3 This is a detailed drawing of the gas dispersion component of this utility model.

[0022] In the diagram: 1. Conveyor; 101. Rotary kiln discharge pipe; 102. Conveyor discharge pipe; 103. First helical blade; 104. Second helical blade; 105. Motor; 2. Cooling mechanism; 201. Cavity; 202. Cold air inlet pipe; 203. Hot air outlet pipe; 3. Outer shell; 301. Hot water outlet pipe; 302. Cold water outlet pipe; 4. Gas dispersion component; 401. Annular plate; 402. Inclined hole; 5. Helical plate. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] In the sulfuric acid process for titanium dioxide production, the temperature of the material after calcination in the rotary kiln reaches as high as 800-1000℃, and it needs to be cooled to below 100℃ for subsequent crushing and packaging. This solution is to cool down the sulfuric acid process for titanium dioxide production.

[0025] like Figures 1-3 As shown, this utility model provides a technical solution: a rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process, including a conveyor 1 and a controller. A rotary kiln discharge pipe 101 is fixedly connected to the top of one side of the conveyor 1, and a conveyor discharge pipe 102 is fixedly connected to the bottom of the other side. The top of the rotary kiln discharge pipe 101 is connected to the rotary kiln, and the rotary kiln discharge pipe 101 is externally connected to a Raymond mill.

[0026] The conveyor 1 includes a conveying housing and a rotating shaft. A motor 105 is fixed on the side of the conveying housing, and the output end of the motor 105 is fixed to the end of the rotating shaft. A first spiral blade 103 is fixed on the shaft near the rotary kiln discharge pipe 101, and a second spiral blade 104 is fixed on the shaft away from the rotary kiln discharge pipe 101. The inclination angle of the first spiral blade 103 is greater than the inclination angle of the second spiral blade 104. In addition, a cooling mechanism 2 is provided on the outside of the conveying housing.

[0027] After the high-temperature titanium dioxide powder enters the conveying housing, the motor 105 drives the rotating shaft to rotate. Driven by the first spiral blade 103 and the second spiral blade 104, the titanium dioxide powder tumbles within the conveying housing while moving along the axial direction of the housing. The spiral blades tumble the material, ensuring uniform cooling. It's important to understand that the larger the angle of the spiral blades (relative to the axial direction of the conveying housing), the faster the axial conveying speed of the material within the housing. In this design, the tilt angle of the first spiral blade 103 is greater than the tilt angle of the second spiral blade 104. This is because, since the material initially enters the conveying housing at a high temperature, if the material moves slowly, the temperature change will be... Large, rapid temperature changes can generate thermal stress inside the particles, leading to particle breakage or surface adhesion, reducing the flowability and dispersibility of the powder. Accelerating material movement speed and reducing residence time in high-temperature zones reduces the severity of temperature changes. The second helical blade 104 can drive the material to move slowly, continuing to propel the material forward at a slower speed after the material temperature decreases, ensuring sufficient cooling during transport. By setting different inclination angles of the helical blades, the material movement speed can be controlled, thereby optimizing the cooling effect, avoiding particle breakage or surface adhesion caused by drastic temperature changes, and improving the quality and performance of the powder.

[0028] like Figure 2 As shown, the cooling mechanism includes a cavity 201 formed on the conveying shell. A hot air outlet pipe 203 is fixedly connected to the side of the cavity 201 near the rotary kiln discharge pipe 101, and a cold air inlet pipe 202 is fixedly connected to the side of the cavity 201 away from the rotary kiln discharge pipe 101. The cold air inlet pipe 202 is fixedly connected to the air outlet of the air-cooled cooler. The cold air generated by the air-cooled cooler enters the cavity 201 through the cold air inlet pipe 202 under the drive of its own fan. After exchanging heat with the conveying shell, it is discharged through the hot air outlet pipe 203. The heat from the discharged hot air is used to preheat the combustion air of the rotary kiln or for heating the plant area. It is understandable that the purpose of setting the cold air inlet pipe 202 away from the rotary kiln discharge pipe 101 is also to prevent the material on the side of the first spiral blade 103 from being rapidly cooled.

[0029] An outer shell 3 is fixed to the outside of the conveying shell, and a gap is formed between the outer shell 3 and the conveying shell. A cold water outlet pipe 302 is fixedly connected to the side of the outer shell 3 near the rotary kiln discharge pipe 101, and a hot water outlet pipe 301 is fixedly connected to the side of the outer shell 3 away from the rotary kiln discharge pipe 101. The cold water outlet pipe 302 is fixedly connected to the outlet of the water-cooled cooler. The cold water generated by the water-cooled cooler enters the gap through the cold water outlet pipe 302 under the drive of its own water pump, thereby exchanging heat with the air flowing in the cavity 201.

[0030] In a specific embodiment of this solution, taking a production line with an annual output of 100,000 tons of titanium dioxide as an example: after calcination, the material (900℃) enters the conveying shell, the spiral blades push the material at a speed of 2r / min, cold air (25℃) enters the cavity 201 at a flow rate of 5m³ / s, cooling water (20℃ inlet water → 80℃ outlet water) enters the gap, and the air is discharged through the hot air outlet pipe 203 at a temperature of about 120-180℃, which is used to preheat the combustion air of the rotary kiln. Finally, the material temperature drops to below 80℃ and is directly conveyed to the Raymond mill for grinding.

[0031] To improve the uniformity of cold air distribution within the cavity 201, thereby uniformly reducing the temperature of the material and improving the cooling effect, several equidistant gas dispersion elements 4 are provided within the cavity 201, through which the cooling gas is uniformly distributed within the cavity 201.

[0032] Specifically, such as Figure 3 As shown, the gas dispersion component 4 includes an annular plate 401. The annular plate 401 has several inclined holes 402 arranged in a circular array. When the cold air enters the cavity 201 and passes through the inclined holes 402, firstly, the cold air is sprayed at a certain angle to generate vortices, thereby prolonging the residence time of the gas in the cavity 201 and improving the cooling efficiency. Secondly, the inclined holes 402 can adjust the airflow resistance, balance the pressure distribution inside the cavity 201, and reduce the energy loss caused by turbulence.

[0033] A spiral plate 5 is fixed in the gap. The spiral plate 5 increases the contact area between the cooling water and the inner wall of the outer shell 3, thereby increasing the heat exchange efficiency of the cooling water.

[0034] In another specific embodiment of this solution, a temperature sensor is fixed on the inner wall of the conveyor discharge pipe 102. The controller is electrically connected to the temperature sensor, the air-cooled cooler, and the water-cooled cooler. The temperature sensor detects the temperature of the material discharged from the conveyor discharge pipe 102. When the temperature of the discharged material is greater than the threshold, the controller controls the air-cooled cooler and the water-cooled cooler to reduce the temperature of the corresponding medium or increase the movement speed of the medium in order to reduce the temperature of the material.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended embodiments and their equivalents.

Claims

1. A rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process, comprising a conveyor (1), characterized in that: The top of one side of the conveyor (1) is fixedly connected to the rotary kiln discharge pipe (101), and the bottom of the other side is fixedly connected to the conveyor discharge pipe (102). The conveyor (1) includes a conveying housing and a rotating shaft. A motor (105) is fixed on the side of the conveying housing. The output end of the motor (105) is fixed to the end of the rotating shaft. A first spiral blade (103) is fixed on the shaft of the rotating shaft near the rotary kiln discharge pipe (101). A second spiral blade (104) is fixed on the shaft of the rotating shaft away from the rotary kiln discharge pipe (101). The inclination angle of the first spiral blade (103) is greater than the inclination angle of the second spiral blade (104). A cooling mechanism (2) is provided on the outside of the conveyor housing.

2. The rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process according to claim 1, characterized in that: The cooling mechanism (2) includes a cavity (201) opened on the conveying shell. A hot gas outlet pipe (203) is fixedly connected to the side of the cavity (201) near the rotary kiln discharge pipe (101). A cold gas inlet pipe (202) is fixedly connected to the side of the cavity (201) away from the rotary kiln discharge pipe (101). The cold gas inlet pipe (202) is fixedly connected to the air outlet of the air-cooled cooler. An outer shell (3) is fixed to the outside of the conveying housing. A gap is formed between the outer shell (3) and the conveying housing. A cold water outlet pipe (302) is fixedly connected to the side of the outer shell (3) near the rotary kiln discharge pipe (101). A hot water outlet pipe (301) is fixedly connected to the side of the outer shell (3) away from the rotary kiln discharge pipe (101). The cold water outlet pipe (302) is fixedly connected to the outlet of the water-cooled cooler.

3. The rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process according to claim 2, characterized in that: The cavity (201) is provided with a number of equally spaced gas dispersion elements (4), and the cooling gas is evenly distributed in the cavity (201) through the gas dispersion elements (4).

4. The rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process according to claim 3, characterized in that: The gas dispersion component (4) includes an annular plate (401), and the annular plate (401) has a plurality of inclined holes (402) arranged in a circular array on its plate body.

5. The rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process according to claim 2, characterized in that: A spiral plate (5) is fixed within the gap.

6. The rotary kiln material cooling device for the preparation of titanium dioxide using the sulfuric acid process according to claim 1, characterized in that: A temperature sensor is fixed to the inner wall of the conveyor discharge pipe (102).

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