A reaction kettle for waste heat recovery in ilmenite acidolysis process

Abstract

The reaction kettle for waste heat recovery in the ilmenite acidolysis process is provided in the paper, and the reaction kettle comprises a reaction kettle body, an ilmenite feeding port, a sulfuric acid feeding port, a cooling water inlet, a cooling water outlet, a discharge port and a cooling water spiral channel, the reaction kettle body is provided with the ilmenite feeding port, the sulfuric acid feeding port and the cooling water outlet above, the cooling water inlet is arranged below the reaction kettle body, the discharge port is arranged at the bottom of the reaction kettle body, the shell of the reaction kettle body is provided with the cooling water spiral channel, the inside of the cooling water spiral channel is coated with a material with good corrosion resistance and heat conduction, the heat generated by the ilmenite acidolysis can be absorbed by the cooling water in the cooling water spiral channel, the waste heat recovery is realized, the recovered hot water can be further used for preheating raw materials or other process links, the energy utilization rate is improved, the production cost is reduced, the problem of waste of waste heat in the ilmenite acidolysis process is effectively solved, and the reaction kettle has a good industrial application prospect.

Description

Technical Field

[0001] This article belongs to the technical field of titanium dioxide production equipment, specifically involving a reaction vessel for waste heat recovery in the acidolysis process of ilmenite. Background Technology

[0002] The acidolysis reaction of ilmenite (mainly FeTiO3) with concentrated sulfuric acid is one of the core steps in the production of titanium dioxide. This reaction is a strongly exothermic reaction. During the reaction, the system temperature can rise rapidly from the initial 60-80℃ to 200-250℃, or even higher (depending on the reaction conditions). The heat released mainly comes from the heat of chemical reaction, and the exothermic reaction is concentrated and intense.

[0003] Therefore, a large amount of heat generated during the acidolysis of ilmenite can be recovered and utilized. Traditional ilmenite acidolysis reactors are usually hollow cylindrical, with the internal space used to hold materials such as ilmenite and concentrated sulfuric acid for the reaction. The materials are generally made of carbon steel or stainless steel. To prevent acid corrosion, the interior is lined with acid-resistant bricks, rubber, plastics, and other anti-corrosion materials. Heating devices are generally installed at the bottom of the reactor, commonly including electric heating plates, electric heating rods, or steam heating pipes, to preheat the materials in the reactor so that they reach the temperature conditions required for the reaction, thus accelerating the acidolysis reaction of ilmenite. However, the heat released by the subsequent acidolysis reaction is wasted.

[0004] Existing ilmenite reactors lack heat recovery and utilization capabilities. Therefore, it is necessary to design a reactor that can effectively recover waste heat from the acidolysis process of ilmenite in order to optimize the production process and improve energy efficiency. Summary of the Invention

[0005] To address the aforementioned issues, this paper proposes a reactor for waste heat recovery during the acidolysis of ilmenite. The reactor includes a reactor body, an ilmenite inlet, a sulfuric acid inlet, a cooling water inlet, a cooling water outlet, a discharge outlet, and a cooling water spiral channel. The ilmenite inlet, sulfuric acid inlet, and cooling water outlet are located at the top of the reactor body, the cooling water inlet is located at the bottom of the reactor body, and the discharge outlet is located at the bottom of the reactor body. The shell of the reactor body is equipped with a cooling water spiral channel, the interior of which is coated with a material that provides both corrosion resistance and good thermal conductivity.

[0006] The reactor body is lined with anti-corrosion bricks, and the reactor body is insulated by thermal insulation material on the outside. By lining the reactor body with anti-corrosion bricks, the inner wall of the reactor can be effectively protected, reducing the corrosive effect of the reaction medium on the reactor body material. The high-performance thermal insulation material layer on the outside of the reactor body can minimize the loss of heat inside the reactor. Through this dual protection design of internal and external protection, the corrosion resistance of the reactor is guaranteed and the thermal energy utilization efficiency is improved, thereby achieving comprehensive protection and energy-saving operation of the reactor.

[0007] The ilmenite feed inlet has a conical structure that is wider at the top and narrower at the bottom, and it is an open design. This unique structural design can effectively reduce the scattering of ilmenite during the dumping process, significantly reduce the waste of ore in the transfer process, and thus improve the resource utilization rate and working environment safety in the production process.

[0008] The aforementioned cooling water spiral channels are spirally distributed inside the shell of the reactor body. These channels connect to both the cooling water inlet and outlet. Cooling water is introduced through the cooling water inlet and discharged through the cooling water outlet after passing through the spiral channels. By flowing through these spiral channels surrounding the reactor body, the cooling water can fully contact the hot surface of the reactor, absorbing the heat generated during the reaction and effectively reducing the internal temperature. After heat exchange, the cooled water absorbs the heat from the reaction, is collected, and transported to subsequent production stages as a preheating medium or other process water. This improves energy efficiency, reduces cooling water waste, and achieves rational energy recovery and utilization.

[0009] The cooling water outlet is equipped with a thermometer, and the cooling water temperature is monitored by the thermometer. By monitoring the temperature changes of the cooling water in real time through thermometers installed at key nodes of the system, operators can grasp the heat release situation. Through accurate temperature measurement, the system can more efficiently adjust the heat exchange process to ensure that the released heat energy is maximized, thereby significantly improving the energy utilization efficiency of the entire system.

[0010] While ensuring the strength of the equipment, the shell of the reactor body and the spiral channel of the cooling water are relatively thin. This thin-walled structure not only reduces the overall weight of the equipment, but also optimizes the heat exchange performance, allowing the cooling medium to absorb the heat generated during the reaction more quickly, thereby ensuring precise control of the reaction temperature.

[0011] Beneficial effects:

[0012] The cooling water spiral channel structure can significantly increase the heat exchange area. This heat exchange method can quickly and effectively remove the heat generated during the reaction. In the acid leaching process of ilmenite, this optimized cooling system can not only efficiently recover and utilize the preheating energy generated during the reaction to achieve energy recycling, but also precisely control the temperature fluctuations in the reactor to ensure that the entire acid leaching reaction is carried out under stable temperature conditions, thereby improving the efficiency of thermal energy utilization.

[0013] By coating the spiral channel of cooling water with a corrosion-resistant and thermally conductive material, an effective protective structure is formed for the wall of the spiral cooling water pipe, extending the service life of the vessel, reducing equipment maintenance and replacement costs caused by corrosion, and also reducing the risk of cooling water contamination, providing clean process water for subsequent processes.

[0014] The thin-walled structure between the reactor shell and the cooling water spiral channel significantly improves the thermal conductivity, thereby effectively enhancing the waste heat recovery efficiency of the entire system. By enhancing the thermal conductivity of the thin wall, heat can be transferred more quickly from the inside of the reactor to the cooling water spiral channel, reducing thermal resistance loss and enabling the cooling water to more fully absorb the waste heat generated during the reaction. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a reactor used for waste heat recovery in the acidolysis process of ilmenite;

[0016] In the diagram: 1. Reactor body; 2. Ilmenite inlet; 3. Sulfuric acid inlet; 4. Cooling water outlet; 5. Cooling water inlet; 6. Discharge outlet; 7. Cooling water spiral channel. Detailed Implementation

[0017] To enhance understanding of the present invention, the invention will be further described in detail below with reference to embodiments and accompanying drawings. These embodiments are only for explaining the invention and do not constitute a limitation on the scope of protection of the invention.

[0018] 1. Reactor body; 2. Ilmenite inlet; 3. Sulfuric acid inlet; 4. Cooling water outlet; 5. Cooling water inlet; 6. Discharge outlet; 7. Cooling water spiral channel.

[0019] like Figure 1 As shown;

[0020] A reactor for waste heat recovery during the acidolysis of ilmenite, comprising a reactor body 1, an ilmenite inlet 2, a sulfuric acid inlet 3, a cooling water inlet 5, a cooling water outlet 4, a discharge outlet 6, and a cooling water spiral channel 7. The reactor body 1 has the ilmenite inlet 2, sulfuric acid inlet 3, and cooling water outlet 4 at the top, the cooling water inlet 5 at the bottom, and the discharge outlet 6 at the bottom. The reactor body 1 has a cooling water spiral channel 7, the interior of which is coated with a corrosion-resistant and thermally conductive material. The reactor body 1 is lined with corrosion-resistant bricks, and the reactor body 1 is insulated externally by a heat-insulating material. The ilmenite inlet 2 has a conical structure that is wider at the top and narrower at the bottom. The ilmenite inlet 2 is an open design. The cooling water spiral channel 7 is spirally distributed inside the shell of the reactor body 1. The cooling water spiral channel 7 is connected to the cooling water inlet 5 and the cooling water outlet 4. The cooling water inlet 5 introduces cooling water through the cooling water spiral channel 7. The cooling water is discharged through the cooling water outlet 4 after passing through the cooling water spiral channel 7. A thermometer is installed at the cooling water outlet 4 to monitor the cooling water temperature. The wall thickness between the shell of the reactor body 1 and the cooling water spiral channel 7 is relatively thin while ensuring the strength of the equipment.

[0021] Implementation example;

[0022] Ilmenite is poured into the reactor body 1 through the ilmenite inlet 2, and sulfuric acid is poured into the reactor body 1 through the sulfuric acid inlet 3. Heat is released during the reaction. Cooling water enters from the cooling water inlet 5, absorbs heat through the cooling water spiral channel 7, and then flows out as hot water through the cooling water outlet 4, thereby realizing the heat recovery during the acidolysis reaction of ilmenite.

[0023] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A reaction vessel for waste heat recovery in the acidolysis process of ilmenite, characterized in that, The reactor includes a reactor body, an ilmenite inlet, a sulfuric acid inlet, a cooling water inlet, a cooling water outlet, a discharge outlet, and a cooling water spiral channel. The ilmenite inlet, sulfuric acid inlet, and cooling water outlet are located at the top of the reactor body, the cooling water inlet is located at the bottom of the reactor body, and the discharge outlet is located at the bottom of the reactor body. The shell of the reactor body is provided with a cooling water spiral channel, and the interior of the cooling water spiral channel is coated with a material that has good corrosion resistance and thermal conductivity.

2. The reactor for waste heat recovery in the acidolysis process of ilmenite according to claim 1, characterized in that, The reactor body is lined with anti-corrosion bricks, and the reactor body is insulated by heat-insulating material on the outside.

3. The reactor for waste heat recovery in the acidolysis process of ilmenite according to claim 1, characterized in that, The ilmenite inlet has a conical structure that is wider at the top and narrower at the bottom, and it is an open design.

4. The reactor for waste heat recovery in the acidolysis process of ilmenite according to claim 1, characterized in that, The cooling water spiral channel is spirally distributed inside the shell of the reactor vessel. The cooling water spiral channel is connected to the cooling water inlet and the cooling water outlet. The cooling water inlet introduces cooling water through the cooling water spiral channel, and the cooling water is discharged through the cooling water outlet after passing through the cooling water spiral channel.

5. The reactor for waste heat recovery in the acidolysis process of ilmenite according to claim 1, characterized in that, A thermometer is installed at the cooling water outlet, and the cooling water temperature is monitored by the thermometer.

6. The reactor for waste heat recovery in the acidolysis process of ilmenite according to claim 1, characterized in that, The shell of the reactor body and the spiral channel of the cooling water are designed to have a relatively thin wall thickness while ensuring the strength of the equipment.

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