Pretreatment mechanism for nitrogen purification

Abstract

The utility model relates to the field, in particular to a pretreatment mechanism for nitrogen purification, which comprises a filter unit, a heat exchanger and an activated carbon canister, the heat exchanger comprises a shell, a water inlet pipe, a water drainage pipe, an air inlet pipe and an air exhaust pipe, wherein the water inlet pipe, the water drainage pipe, the air inlet pipe and the air exhaust pipe are fixedly installed on the shell. A flow equalizing assembly, a plurality of heat exchange pipes and a plurality of baffle plates are installed in the shell. The heat exchange tube penetrates through the baffle plate, a via hole is formed in the baffle plate, and a guide tube is fixedly mounted at the via hole; and the inner diameter of the guide pipe is not changed or is sequentially increased from the airflow direction or is sequentially reduced along the airflow direction. According to the heat exchanger, the contact area of air and the baffle plates can be increased through the guide pipes, so that the heat exchange effect is better, and the change of the pressure intensity can be caused by the change of the inner diameter of the guide pipes.

Description

Technical Field

[0001] This utility model relates to the field of nitrogen purification technology, specifically to a pretreatment mechanism for nitrogen purification. Background Technology

[0002] Chinese Patent Application No. 202222570671.4 discloses a vacuum pressure swing adsorption (PSA) oxygen generator, relating to the field of oxygen production technology. It includes a base on which a Roots blower, a front-end cooler, a first lithium-type molecular sieve adsorption tower, a second lithium-type molecular sieve adsorption tower, a PLC controller, a wet Roots vacuum pump, an oxygen buffer tank, and a back-end cooler are sequentially mounted. The air inlet of the Roots blower is connected to a pre-filter via a pipe. This PSA oxygen generator uses air as raw material. After being filtered by the pre-filter, the air enters the Roots blower for pressurization, followed by cooling and adsorption. The produced oxygen-enriched oxygen, after buffering and adjustment, undergoes secondary cooling and filtration through the back-end cooler and an antibacterial high-efficiency air filter before being delivered to the oxygen user. This secondary air filtration and cooling improves the quality of the oxygen, obtaining relatively standard clean oxygen, thus ensuring oxygen purity and greatly increasing the practicality of the PSA oxygen generator.

[0003] Chinese Patent Application No. 202222570671.4, paragraph 0017, states that "the air inlet of the Roots blower 2 is connected to a primary air filter 10 via a pipe, and the air outlet of the Roots blower 2 is connected to a front-end cooler 3 via a pipe."

[0004] Chinese Patent Application No. 202420484883.7 discloses an interstage cooler. This interstage cooler includes: a shell, an inlet, an outlet, a tube sheet, a tube bundle, and several baffles. The tube sheet and baffles located on the far right of the shell, together with the shell, form a first buffer zone; the tube sheet and baffles located on the far left of the shell, together with the shell, form a second buffer zone; guide plates are respectively arranged in the first and second buffer zones, and the guide plates are densely covered with multiple guide holes that allow airflow. This application, by setting guide plates in the first and second buffer zones of the interstage cooler, increases the contact time and contact area between the high-temperature gas and the cooling water twice, further improving the cooling effect of the gas. This further reduces the temperature of the gas discharged from the outlet, thereby keeping the temperature of the gas entering the second and third stage cryogenic air compressor within a specified range, thus ensuring the intake volume of the second and third stage cryogenic air compressor.

[0005] The Chinese patent application number 202222570671.4 states that in actual operation, the Roots blower will increase the air flow rate, which on the one hand affects the separation of nitrogen and oxygen, and on the other hand reduces the contact time between the cooling pipe and the air, resulting in insufficient cooling.

[0006] The Chinese patent with application number 202420484883.7 cannot affect the airflow rate.

[0007] Therefore, it is necessary to provide a new technical solution to overcome the above-mentioned defects. Utility Model Content

[0008] The purpose of this invention is to provide a pretreatment mechanism for nitrogen purification that can effectively solve the above-mentioned technical problems.

[0009] To achieve the purpose of this utility model, the following technical solution is adopted:

[0010] A pretreatment mechanism for nitrogen purification includes: a filtration unit, a heat exchanger, and an activated carbon tank.

[0011] The heat exchanger includes: a shell, an inlet pipe, a drain pipe, an air inlet pipe and an exhaust pipe fixedly installed on the shell, and a flow equalization assembly and a plurality of heat exchange tubes and baffles installed inside the shell;

[0012] The heat exchange tube passes through the baffle plate, which has a through hole, and a guide tube is fixedly installed at the through hole; the inner diameter of the guide tube remains unchanged or increases sequentially in the airflow direction or decreases sequentially along the airflow direction.

[0013] Furthermore, the adjacent baffles have staggered vias.

[0014] Furthermore: the filtration unit is divided into a primary filter and a secondary filter, and the heat exchanger is disposed between the primary filter and the secondary filter.

[0015] Furthermore: the primary filter is connected to an air inlet pipe and an air outlet pipe, the diameter of the air outlet pipe is 1.2 times the diameter of the air inlet pipe, and the air inlet pipe is connected to the air inlet pipe.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention relates to a pretreatment mechanism for nitrogen purification. The guide tube can increase the contact area between air and baffles, resulting in better heat exchange. The change in the inner diameter of the guide tube can cause a change in pressure. Attached Figure Description

[0018] The accompanying drawings are provided to further understand the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof.

[0019] Figure 1 This is a schematic diagram of the pretreatment mechanism for nitrogen purification according to this utility model.

[0020] Figure 2 This is an isometric view of the heat exchanger of the nitrogen purification pretreatment mechanism of this utility model.

[0021] Figure 3 This is a cross-sectional view of the heat exchanger of the nitrogen purification pretreatment mechanism of this utility model.

[0022] Figure 4 This is a schematic diagram of the heat exchange tube, baffle plate, and guide tube of the pretreatment mechanism for nitrogen purification of this utility model.

[0023] In the diagram: 1. Filter unit; 2. Heat exchanger; 3. Activated carbon tank; 11. Primary filter; 12. Secondary filter; 111. Inlet pipe; 112. Exhaust pipe; 21. Shell; 22. Water inlet pipe; 23. Drain pipe; 24. Inlet pipe; 25. Exhaust pipe; 26. Heat exchanger tube; 27. Baffle plate; 28. Guide pipe; 29. ​​Cavity; 20. Baffle; 201. Return plate. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0025] In the description of this utility model, it should be understood that the terms "center," "lateral," "longitudinal," "front," "rear," "left," "right," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. When a component is referred to as being "fixed to" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be an intermediate component at the same time. When a component is considered to be "set on" another component, it can be directly set on the other component or there may be an intermediate component at the same time. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.

[0026] like Figures 1 to 4As shown, the pretreatment mechanism for nitrogen purification of this utility model includes: a filter unit 1, a heat exchanger 2, and an activated carbon tank 3; after simple filtration, the air enters the heat exchanger 2 for heating or cooling. During the adsorption and separation process of nitrogen, the working pressure is in the range of 0.8MPa to 1.2MPa, and the temperature is in the range of 20 degrees Celsius to 25 degrees Celsius, achieving a good balance between nitrogen yield and purity; after thorough dust removal by the activated carbon tank 3, the air enters the pressure swing adsorption mechanism.

[0027] The filter unit 1 is divided into a primary filter 11 and a secondary filter 12. The heat exchanger 2 is disposed between the primary filter 11 and the secondary filter 12. The primary filter 11 is connected to an air inlet pipe 111 and an air outlet pipe 112. The diameter of the air outlet pipe 112 is 1.2 times the diameter of the air inlet pipe 111. The air inlet pipe 111 is connected to the air inlet pipe 24.

[0028] The air first passes through the primary filter 11 for dust removal. Multiple secondary filters 12 can be set. In this application, two are set. Of course, it is also possible not to set secondary filters 12. The activated carbon tank 3 can adsorb most of the impurities. Setting multiple secondary filters 12 can reduce the number of times the activated carbon tank 3 needs to be cleaned.

[0029] It should be noted that the intake pipe 111 is connected to the Roots blower, and the Roots blower sends air into the primary filter 11. Since the diameter of the exhaust pipe 112 is 1.2 times that of the intake pipe 111, the pressure can be reduced.

[0030] The heat exchanger 2 includes: a shell 21, a water inlet pipe 22, a drain pipe 23, an air inlet pipe 24 and an exhaust pipe 25 fixedly installed on the shell 21, and a plurality of heat exchange tubes 26 and baffles 27 installed inside the shell 21; the exhaust pipe 112 is connected to the air inlet pipe 24.

[0031] Cooling water enters the flow equalization component inside the shell 21 through the water inlet pipe 22. After the flow equalization effect of the flow equalization component, it enters the heat exchange tube 26 and exchanges heat with the air.

[0032] The flow equalization assembly includes a cavity 29, a baffle 20, and a return plate 201. The ends of the heat exchange tube 26 and the water inlet pipe 22 are inserted into the cavity 29. The baffle 20 is fixedly connected to the interior of the cavity 29 and is located at the water inlet pipe 22. A channel is provided between the lower end of the baffle 20 and the bottom surface of the cavity 29, through which water flows. The function of this channel is to increase the area of ​​the water flow. The return plate 201 is an arc-shaped plate. When the water flow impacts the arc surface, it flows along the arc surface, thereby forming a convergence of water flows. On the one hand, this makes the water flow chaotic to achieve flow equalization, and on the other hand, it allows the water flow to exchange heat, making the water temperature more uniform.

[0033] The heat exchange tube 26 passes through the baffle plate 27, which has through holes through which air flows. Adjacent baffle plates 27 have staggered through holes, creating a baffle and extending the airflow path for more efficient heat exchange. A guide tube 28 is fixedly installed at each through hole. It is important to note that multiple guide tubes 28 are fixedly installed on each baffle plate 27. The guide tubes 28 increase the contact area between the air and the baffle plate 27, improving heat exchange. Considering cost and manufacturing processes, a guide tube 28 with a radius of 5 cm is generally selected. The inner diameter of the guide tube 28 can remain constant, increase sequentially with the airflow direction, or decrease sequentially along the airflow direction. Changing the inner diameter of the guide tube 28 causes a change in pressure. When the inner diameter of the guide tube 28 increases sequentially with the airflow direction, the air pressure decreases and the flow velocity decreases as the airflow passes through the funnel-shaped guide tube 28. When the inner diameter of the guide tube 28 decreases sequentially with the airflow direction, the air pressure increases and the flow velocity increases.

[0034] The guide tube 28 can increase the contact area between air and baffle 27, resulting in better heat exchange. The change in the inner diameter of the guide tube 28 can cause a change in pressure.

[0035] Finally, it should be noted that the upper part of the shell 21 is provided with a sealing plate, the upper end of the heat exchange tube 26 passes through the sealing plate and is inserted into the closed space formed by the sealing plate and the inner wall of the shell 21, and the cooling water enters the closed space and then enters the drain pipe 23.

[0036] All standard parts used in this utility model can be purchased from the market, and irregular parts can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art. In addition, the circuit connection adopts conventional connection methods in the prior art, which will not be described in detail here. The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0037] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A pretreatment mechanism for nitrogen gas purification, characterized by: The utility model relates to a filter unit, heat exchanger and activated carbon tank are included: The heat exchanger includes: the shell, fixed mounting on the water inlet pipe, drain pipe, air inlet pipe and exhaust pipe of shell, the shell inside installation has flow assembly and a plurality of heat exchange pipe, baffle; The heat exchange pipe passes through the baffle, the baffle is equipped with through hole, the through hole is fixedly installed with guide pipe;The inner diameter of guide pipe is invariable or increases gradually or decreases gradually along the direction of air flow. Adjacent baffle, through hole staggered arrangement.

2. The pretreatment mechanism for purifying nitrogen according to claim 1, characterized by: The filter unit is divided into primary filter and secondary filter, and the heat exchanger is arranged between the primary filter and the secondary filter.

3. The pretreatment mechanism for purifying nitrogen according to claim 2, characterized by: The primary filter is connected with the air inlet pipe and the air outlet pipe, the pipe diameter of the air outlet pipe is 1.2 times of the air inlet pipe, and the air inlet pipe is communicated with the air inlet pipe.

4. The pretreatment mechanism for purifying nitrogen according to claim 3, wherein: ​

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