Alkali liquor diluting device

Abstract

The utility model relates to an alkali liquor diluting device. The alkali liquor diluting device comprises an upper mixing bin, a shell-and-tube heat exchanger and a lower storage tank which are sequentially arranged from top to bottom, two ends of a tube pass of the shell-and-tube heat exchanger are respectively communicated with the upper mixing bin and the lower storage tank, and circulating cooling water is introduced into a shell pass; a liquid inlet hole and an exhaust hole are formed in the top of the upper mixing bin, a liquid outlet hole is formed in the bottom of the lower storage tank, and the upper mixing bin and the lower storage tank are connected through a gas-phase balance pipe to achieve dynamic pressure compensation. During working, alkali liquor and desalted water are mixed and then enter the upper mixing bin, flow into the tube pass of the shell-and-tube heat exchanger after being primarily homogenized by turbulent flow of the baffle plate, are subjected to forced convection heat exchange with cooling water of the shell pass, are cooled by 5-10 DEG C and then enter the lower storage tank. By integrating a vertical heat exchange and branch bin pressure stabilizing structure, thermal expansion pressure fluctuation is balanced, dilution concentration detection errors are reduced, possible crystallization precipitation can be inhibited, and the device has the characteristics of accurate temperature regulation and control, high system stability and convenience in maintenance, and is suitable for high-precision alkali liquor blending scenes in the fields of chemical engineering, environmental protection and the like.

Description

Technical Field

[0001] This utility model relates to the field of liquid-liquid mixing equipment technology, and specifically to an alkaline solution dilution device. Background Technology

[0002] In chemical production processes, the alkali dilution system is a crucial link in achieving process regulation and material handling. Traditional alkali dilution devices mostly use static mixers to achieve concentration adjustment and use compartmentalized storage tanks to achieve buffering and stable output.

[0003] As shown in the utility model patent with authorization announcement number CN219879803U, a partition divides the storage tank into upper and lower cavities, effectively solving the problems of pressure fluctuation and liquid level interference within the storage tank, in conjunction with an automatic liquid level gauge and a pressure balancing structure. However, in actual industrial applications, it has been found that high-concentration alkaline solutions easily produce exothermic reactions when mixed with demineralized water. Coupled with changes in ambient temperature, this can easily lead to an increase in the temperature of the alkaline solution within the storage tank, resulting in the following problems: 1) High temperatures may cause the alkaline solution to crystallize and precipitate, causing pipeline blockage; 2) Temperature fluctuations affect the accuracy of dilution concentration; 3) Thermal expansion effects disrupt the pressure balance of the storage tank; 4) High-temperature environments exacerbate equipment corrosion. Although existing technologies have made breakthroughs in concentration regulation and pressure control, they have not optimized temperature control, especially lacking a temperature-coordinated management scheme for the structure of compartmentalized storage tanks. Some improvement schemes attempt to add external cooling devices, but these suffer from structural redundancy, low heat exchange efficiency, and incompatibility with the liquid level interlocking system of compartmentalized storage tanks. Therefore, there is an urgent need for an alkaline dilution device that can achieve precise temperature control and be deeply integrated with compartmentalized storage tanks to improve system stability and process adaptability. Utility Model Content

[0004] In order to overcome the above-mentioned defects of existing alkaline solution dilution, this utility model provides an alkaline solution dilution device.

[0005] The technical solution adopted by this utility model is as follows: an alkaline dilution device includes an upper mixing chamber, a shell-and-tube heat exchanger, and a lower storage tank installed sequentially from top to bottom. The upper and lower ends of the tube side of the shell-and-tube heat exchanger are respectively connected to the upper mixing chamber and the lower storage tank. Circulating cooling water flows through the shell side of the shell-and-tube heat exchanger. A gas phase balance pipe is provided between the upper mixing chamber and the lower storage tank. A liquid inlet is provided at the top of the upper mixing chamber, and a liquid outlet is provided at the bottom of the lower storage tank.

[0006] Preferably, the top of the upper mixing chamber is provided with an exhaust port.

[0007] Preferably, the upper mixing chamber near the top of the chamber and the lower storage tank near the top of the tank are respectively provided with a first balance port and a second balance port, and the gas phase balance pipe is connected between the first balance port and the second balance port.

[0008] Preferably, the shell and tube heat exchanger has an outlet at the upper end and an inlet at the lower end, with the outlet and inlet arranged at a 180° angle, and a drain port at the lowest end of the shell and tube heat exchanger.

[0009] Preferably, the upper mixing chamber is provided with a plurality of staggered baffles.

[0010] Preferably, the lower storage tank has a downwardly recessed baffle at the tank opening, which divides the lower storage tank into an upper chamber and a lower chamber. A flow pipe is provided between the upper chamber and the lower chamber. One end of the flow pipe is connected to the lowest point of the baffle, and the other end extends to the outside of the lower storage tank and communicates with the lower chamber. A control valve is provided on the exposed part of the flow pipe.

[0011] Preferably, the lower cavity is provided with a viewing mirror and a viewing lamp, and the viewing mirror and the viewing lamp are arranged at a 180° angle.

[0012] This utility model has the following beneficial effects:

[0013] 1. Improved temperature control and process stability: By integrating a shell-and-tube heat exchanger between the upper mixing chamber and the lower storage tank, and utilizing the vertically connected tube structure, the high-temperature diluted alkali solution flows through the heat exchange tube bundle under gravity and undergoes forced convection heat exchange with the shell-side circulating cooling water. This controls the alkali solution temperature drop to 5-10℃, reducing the impact of temperature fluctuations on the concentration detection system and suppressing potential alkali crystallization. In addition, the turbulence enhancement effect of the baffles further improves the mixing uniformity and heat exchange efficiency, reducing dilution concentration errors.

[0014] 2. Pressure balance: The gas phase balance pipe connects the gas phase space of the upper mixing chamber and the lower storage tank. Together with the exhaust port on the top of the upper mixing chamber, a dynamic pressure compensation mechanism is constructed. During the alkaline solution transportation process, the pressure difference between the two chambers can be quickly balanced, avoiding the deformation of the chamber or the failure of the seal due to the thermal expansion effect caused by temperature changes. This reduces the range of system pressure fluctuations and significantly improves equipment safety.

[0015] 3. Compartmental Design: The lower storage tank is divided into upper and lower compartments by a partition. The linkage design of the flow pipe and control valve realizes segmented liquid level control, avoiding temperature back-mixing of the cooled alkali solution during the output process. At the same time, the compartments are equipped with a two-way observation system of sight glasses and sight lights to realize visual monitoring of liquid level.

[0016] 4. Energy efficiency optimization: The shell and tube heat exchanger adopts a 180° opposing inlet and outlet arrangement, combined with the discharge inlet at the bottom of the shell side, to form a vortex cooling water flow field, which improves heat exchange efficiency. Attached Figure Description

[0017] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model.

[0018] Figure 2 This is a schematic diagram (top view) of the pipe opening according to an embodiment of this utility model.

[0019] Upper mixing chamber 1, baffle 1.1;

[0020] Shell and tube heat exchanger 2;

[0021] Lower storage tank 3, baffle 3.1, upper chamber 3.2, lower chamber 3.3, flow pipe 3.4, control valve 3.5, sight glass 3.6, sight light 3.7;

[0022] Gas phase balance tube 4;

[0023] Liquid inlet N1, liquid outlet N2, vent N3, first balance port N4, second balance port N5, water outlet N6, water inlet N7, drain port N8. Detailed Implementation

[0024] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0025] In the embodiments, such as Figure 1 , Figure 2 The diagram shows an alkali dilution device, comprising an upper mixing chamber 1, a shell-and-tube heat exchanger 2, and a lower storage tank 3, installed sequentially from top to bottom. The upper and lower ends of the tube side of the shell-and-tube heat exchanger 2 are connected to the upper mixing chamber 1 and the lower storage tank 3, respectively. Circulating cooling water flows through the shell side of the shell-and-tube heat exchanger 2. A gas phase balance pipe 4 is provided between the upper mixing chamber 1 and the lower storage tank 3. An inlet N1 is provided at the top of the upper mixing chamber 1, and an outlet N2 is provided at the bottom of the lower storage tank 3. In this embodiment, the inlet N1 is connected to the alkali solution and demineralized water mixed by the static mixer. Through the vertically integrated structure of the upper mixing chamber 1, the shell-and-tube heat exchanger 2, and the lower storage tank 3, the tube side of the shell-and-tube heat exchanger 2 is connected to achieve gravity flow and forced convection heat exchange of the alkali solution. Combined with the shell-side circulating cooling water, the temperature is precisely controlled and reduced by 5-10°C, eliminating the risk of alkali solution crystallization. The gas phase balance pipe 4 connects the gas phase spaces of the two chambers, dynamically offsetting thermal expansion pressure fluctuations and improving system stability and safety. The inlet hole N1 and the outlet hole N2 form a continuous flow path to ensure process continuity.

[0026] In the embodiments, such as Figure 1 , Figure 2As shown, the top of the upper mixing chamber 1 is equipped with an exhaust port N3. The exhaust port N3 at the top of the upper mixing chamber 1 can promptly discharge the gas generated during the mixing process, preventing gas accumulation and abnormal pressure, while maintaining pressure balance within the chamber to prevent liquid flow obstruction or uneven mixing. In addition, the exhaust port N3 can also be connected to a split-range pressure control system as disclosed in patent document CN219879803U, achieving precise control of the internal pressure of the tank. This system combines multiple functions such as safety protection, quality assurance, and process stability. Furthermore, nitrogen sealing can reduce the risk of alkali evaporation or crystallization blockage within the tank, extending the equipment's service life.

[0027] In the embodiments, such as Figure 1 , Figure 2 As shown, a first balance port N4 and a second balance port N5 are respectively located near the top of the upper mixing chamber 1 and the lower storage tank 3. A gas phase balance pipe 4 is connected between the first balance port N4 and the second balance port N5. The first balance port N4 and the second balance port N5 are located near the top of the upper mixing chamber 1 and the lower storage tank 3, respectively, so that the gas phase balance pipe 4 connects the high-level gas phase zones of the two chambers, ensuring rapid pressure compensation response, reducing the interference of liquid level fluctuations on pressure balance, and enhancing the accuracy of dynamic pressure regulation.

[0028] In the embodiments, such as Figure 1 , Figure 2 As shown, the shell-and-tube heat exchanger 2 has an outlet N6 at the upper end and an inlet N7 at the lower end, with the outlet N6 and inlet N7 arranged at a 180° angle. A drain port N8 is located at the bottom of the shell-and-tube heat exchanger 2. The 180° angle between the outlet N6 and inlet N7 creates a vortex cooling water flow field, improving the turbulence of the shell-side cooling water and heat exchange efficiency. The drain port N8, located at the bottom of the shell, facilitates the complete drainage of residual liquid from the shell side, preventing scaling or corrosion.

[0029] In the embodiments, such as Figure 1 , Figure 2 As shown, the upper mixing chamber 1 is equipped with several staggered baffles 1.1. The staggered baffles 1.1 in the upper mixing chamber 1 can extend the flow path of the alkali solution, enhance the turbulence effect, promote the full mixing of high-concentration alkali solution and demineralized water, and at the same time improve the contact efficiency with the tube wall of the shell and tube heat exchanger 2, thereby enhancing the heat exchange effect.

[0030] In the embodiments, such as Figure 1 , Figure 2As shown, a downward-recessed baffle 3.1 is provided at the opening of the lower storage tank 3, dividing the lower storage tank 3 into an upper chamber 3.2 and a lower chamber 3.3. A flow pipe 3.4 is provided between the upper chamber 3.2 and the lower chamber 3.3. One end of the flow pipe 3.4 is connected to the lowest point of the baffle 3.1, and the other end extends to the outside of the lower storage tank 3 and communicates with the lower chamber 3.3. A control valve 3.5 is provided on the exposed part of the flow pipe 3.4. The baffle 3.1 divides the lower storage tank 3 into the upper chamber 3.2 and the lower chamber 3.3. The flow pipe 3.4 achieves segmented liquid level control through the control valve 3.5, preventing the high-temperature alkaline solution in the upper chamber from flowing directly into the lower chamber and preventing temperature back-mixing. The connection of the lowest point of the baffle 3.1 to the flow pipe 3.4 ensures that the liquid in the upper chamber is completely drained, avoiding dead zone accumulation. The control valve 3.5 can be manually controlled or, depending on the actual working conditions, can be an automatic control valve based on parameters such as liquid level and temperature.

[0031] In the embodiments, such as Figure 1 , Figure 2 As shown, the lower cavity 3.3 is equipped with a sight glass 3.6 and a sight lamp 3.7, which are arranged at a 180° angle. The sight glass 3.6 and the sight lamp 3.7 are arranged opposite each other at a 180° angle, forming a bidirectional transmission light path, eliminating blind spots in observation, and working with the transparent area of ​​the lower cavity 3.3 to achieve high-definition visual monitoring of the liquid level, thereby improving operational safety and the accuracy of liquid level control.

[0032] Obviously, the above embodiments of this utility model are merely examples for illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Other obvious variations or modifications derived from the essential spirit of the present utility model still fall within the protection scope of the present utility model.

Claims

1. A caustic dilution apparatus, comprising: The device includes an upper mixing chamber (1), a shell-and-tube heat exchanger (2), and a lower storage tank (3) installed sequentially from top to bottom. The upper and lower ends of the tube side of the shell-and-tube heat exchanger (2) are connected to the upper mixing chamber (1) and the lower storage tank (3) respectively. Circulating cooling water flows through the shell side of the shell-and-tube heat exchanger (2). A gas phase balance pipe (4) is provided between the upper mixing chamber (1) and the lower storage tank (3). The top of the upper mixing chamber (1) is provided with a liquid inlet (N1), and the bottom of the lower storage tank (3) is provided with a liquid outlet (N2).

2. The caustic dilution apparatus of claim 1, wherein, The top of the upper mixing chamber (1) is provided with an exhaust port (N3).

3. The caustic dilution apparatus of claim 1, wherein, The upper mixing chamber (1) near the top of the chamber and the lower storage tank (3) near the top of the tank are respectively provided with a first balance port (N4) and a second balance port (N5), and the gas phase balance pipe (4) is connected between the first balance port (N4) and the second balance port (N5).

4. The caustic dilution apparatus of claim 1, wherein, The shell-and-tube heat exchanger (2) has an outlet (N6) at the upper end and an inlet (N7) at the lower end. The outlet (N6) and the inlet (N7) are arranged at a 180° angle. The bottom of the shell-and-tube heat exchanger (2) has a drain port (N8).

5. The caustic dilution apparatus of claim 1, wherein, The upper mixing chamber (1) is provided with several staggered baffles (1.1).

6. The caustic dilution apparatus of claim 1, wherein, The lower storage tank (3) has a recessed partition (3.1) at the tank opening, which divides the lower storage tank (3) into an upper chamber (3.2) and a lower chamber (3.3). A flow pipe (3.4) is provided between the upper chamber (3.2) and the lower chamber (3.3). One end of the flow pipe (3.4) is connected to the lowest point of the partition (3.1), and the other end extends to the outside of the lower storage tank (3) and communicates with the lower chamber (3.3). A control valve (3.5) is provided on the exposed part of the flow pipe (3.4).

7. The caustic dilution apparatus of claim 6, wherein, The lower cavity (3.3) is provided with a viewing mirror (3.6) and a viewing lamp (3.7), and the viewing mirror (3.6) and the viewing lamp (3.7) are arranged at a 180° angle.

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