Miniaturized liquid oxygen cold energy recovery device

Abstract

The utility model relates to a miniaturized liquid oxygen cold energy recovery device which comprises an air compressor, a freezing dryer, a molecular sieve purifier, a heat exchanger, a liquid air storage tank, a liquid oxygen pump and a liquid oxygen storage tank, the molecular sieve purifier is provided with two groups of inlets and outlets, namely an air inlet and an air outlet, and an analytic gas inlet and an analytic gas outlet; the heat exchanger is provided with three groups of inlets and outlets, namely a first heat exchange inlet and a first heat exchange outlet, a second heat exchange inlet and a second heat exchange outlet, and a third heat exchange inlet and a third heat exchange outlet; the air compressor, the freezing dryer and the molecular sieve purifier are sequentially connected in series, the freezing dryer is communicated with an air inlet of the molecular sieve purifier, an air outlet of the molecular sieve purifier is communicated with the first heat exchange inlet, the first heat exchange outlet is led out in two ways, one way is connected with the liquid air storage tank, the other way is communicated with the second heat exchange inlet, and the second heat exchange outlet is communicated with the desorption gas inlet; the liquid oxygen storage tank communicates with the third heat exchange inlet through a liquid oxygen pump, the third heat exchange outlet is used for being connected with a user oxygen pipe network, and liquid oxygen in the liquid oxygen storage tank uses cold energy for liquid air preparation through a heat exchanger. According to the liquid oxygen cold energy recovery device, the small-size design is achieved for scattered and small-volume liquid oxygen cold energy recovery, and the liquid oxygen cold energy recovery device is suitable for small-scale users.

Description

Technical Field

[0001] The utility model belongs to the technical field of liquid oxygen cold energy recovery and relates to a miniaturized liquid oxygen cold energy recovery device. Background Art

[0002] Liquid oxygen is a light blue liquid with strong paramagnetism. It is oxygen in liquid form. It is widely used in metallurgy, aerospace, health care, electronic manufacturing, environmental protection and other fields. With the rapid development of my country's modernization, liquid oxygen is also used in metal cutting and welding, coolants in scientific research, energy fields (such as boilers and process heaters), glass manufacturing, medicine and biotechnology, pulp and paper, oil refining, water and wastewater treatment and other fields. In short, liquid oxygen is a key basic industrial raw material and medical gas. The total expansion ratio of liquid oxygen is as high as 800:1. Liquid is more economical to transport than gas. Because of this advantage, it is widely used in industrial production and military in modern times. At present, liquid oxygen users show a trend of small quantity and dispersion. Liquid oxygen is usually vaporized by air-temperature vaporizer during use. During the vaporization process of liquid oxygen, a large amount of cold is directly discharged into the air and is not recycled. Liquid oxygen cold recovery is to recover the cold generated by liquid oxygen vaporization and produce liquid air, and use it effectively to save some electricity.

[0003] The existing cold recovery technology is mainly aimed at large-scale cold recovery, and the technology is relatively mature. However, it is more difficult to achieve decentralized, small-volume cold recovery, and there is currently no mature device. Utility Model Content

[0004] In view of this, the purpose of the present invention is to solve the above-mentioned problem and provide a miniaturized liquid oxygen cooling capacity recovery device.

[0005] In order to achieve the above object, the utility model provides the following technical solutions:

[0006] A miniaturized liquid oxygen cold capacity recovery device comprises an air compressor, a cold dryer, a molecular sieve purifier, a heat exchanger, a liquid air storage tank, a liquid oxygen pump, and a liquid oxygen storage tank; the molecular sieve purifier is provided with two groups of inlets and outlets, namely an air inlet and an air outlet, and a desorption gas inlet and a desorption gas outlet; the heat exchanger is provided with three groups of inlets and outlets, namely a first heat exchange inlet and a first heat exchange outlet, a second heat exchange inlet and a second heat exchange outlet, and a third heat exchange inlet and a third heat exchange outlet;

[0007] The air compressor, the cold dryer, and the molecular sieve purifier are connected in series in sequence, the cold dryer is connected to the air inlet of the molecular sieve purifier, the air outlet of the molecular sieve purifier is connected to the first heat exchange inlet, the first heat exchange outlet is divided into two paths, one path is connected to the liquid air storage tank, and the other path is connected to the second heat exchange inlet, and the second heat exchange outlet is connected to the analytical gas inlet;

[0008] The liquid oxygen storage tank is connected to the third heat exchange inlet through a liquid oxygen pump, and the third heat exchange outlet is used to connect to the user's oxygen pipeline network. The liquid oxygen in the liquid oxygen storage tank uses cold energy for liquid air preparation through a heat exchanger.

[0009] Furthermore, a throttle valve is provided between the first heat exchange outlet and the second heat exchange inlet, and between the first heat exchange outlet and the liquid-air storage tank.

[0010] Furthermore, the air compressor adopts an oil-free water-lubricated screw machine, the motor of the air compressor adopts a permanent magnet motor, and is equipped with a vector inverter.

[0011] Furthermore, the cold dryer and the molecular sieve purifier are an integrated structure.

[0012] Furthermore, it also includes a skid-mounted base, and the air compressor, cold dryer, molecular sieve purifier, and heat exchanger are all arranged on the skid-mounted base.

[0013] Furthermore, the third heat exchange inlet is located in the middle and lower part of the heat exchanger, so that the liquid oxygen does not flow through the bottom of the heat exchanger, ensuring that the liquid oxygen evaporates at a suitable position. If it is at the bottom of the heat exchanger, the temperature is lower than the saturation temperature of the liquid oxygen and it cannot be vaporized smoothly.

[0014] Furthermore, it also includes a control system, and the air compressor, cold dryer, molecular sieve purifier, heat exchanger, liquid air storage tank, liquid oxygen pump, and liquid oxygen storage tank are all connected to the control system and controlled by the control system.

[0015] The beneficial effects of the utility model are:

[0016] 1. This utility model aims at recovering the cold energy of dispersed and small-volume liquid oxygen, and realizes a miniaturized design, which is suitable for users with smaller scale. The cold energy generated by the vaporization of liquid oxygen is recovered and liquid air is produced. This effectively utilizes the cold energy of liquid oxygen and saves some electricity.

[0017] 2. The utility model adopts an oil-free water-lubricated screw machine to improve the isothermal compression efficiency and save energy. The analytical gas of the molecular sieve purifier can be preheated by the residual heat between the air compressor stages when heating, saving the analytical power consumption.

[0018] 3. The utility model does not use a flash evaporator, which maintains the stability of the purity of the liquid air product and prevents the safety risk of transportation and storage when the oxygen content of the liquid air exceeds 23%. Fully automatic control is achieved through the control system, and the load can be adjusted from 0 to 100% according to the user's oxygen consumption, reducing energy waste and improving labor productivity.

[0019] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and will be apparent to those skilled in the art based on the following examination and research, or can be taught from the practice of the present invention to some extent. The objectives and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be described in detail below in conjunction with the accompanying drawings, in which:

[0021] Figure 1 This is the principle diagram of the small-scale liquid oxygen cooling capacity recovery device of the utility model.

[0022] Figure markings: 1-air compressor; 2-cold dryer; 3-molecular sieve purifier; 4-heat exchanger; 5-liquid air storage tank; 6-liquid oxygen pump; 7-liquid oxygen storage tank; 31-air inlet; 32-air outlet; 33-analysis gas inlet; 34-analysis gas outlet; 41-first heat exchange inlet; 42-first heat exchange outlet; 43-second heat exchange inlet; 44-second heat exchange outlet; 45-third heat exchange inlet; 46-third heat exchange outlet. DETAILED DESCRIPTION

[0023] The following describes the implementation of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. The following embodiments and the features in the embodiments can be combined with each other without conflict.

[0024] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present utility model. In order to better illustrate the embodiments of the present utility model, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0025] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "back" and the like indicate directions or positional relationships, they are based on the directions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0026] See also Figure 1 , which is a miniaturized liquid oxygen cold recovery device, including an air compressor 1, a cold dryer 2, a molecular sieve purifier 3, a heat exchanger 4, a liquid air storage tank 5, a liquid oxygen pump 6, and a liquid oxygen storage tank 7; the molecular sieve purifier 3 is provided with two groups of inlets and outlets, namely an air inlet 31 and an air outlet 32, and a desorption gas inlet 33 and a desorption gas outlet 34; the heat exchanger 4 is provided with three groups of inlets and outlets, namely a first heat exchange inlet 41 and a first heat exchange outlet 42, a second heat exchange inlet 43 and a second heat exchange outlet 44, and a third heat exchange inlet 45 and a third heat exchange outlet 46; the third heat exchange inlet 45 is located in the middle and lower part of the heat exchanger 4 to ensure that the liquid oxygen evaporates at a suitable position and is smoothly liquefied.

[0027] Among them, the air compressor 1, the cold dryer 2, and the molecular sieve purifier 3 are connected in series in sequence, the cold dryer 2 is connected to the air inlet 31 of the molecular sieve purifier 3, the air outlet 32 ​​of the molecular sieve purifier 3 is connected to the first heat exchange inlet 41, the first heat exchange outlet 42 is divided into two paths, one path is connected to the liquid air storage tank 5, and the other path is connected to the second heat exchange inlet 43, and the second heat exchange outlet 44 is connected to the analytical gas inlet 33;

[0028] The liquid oxygen storage tank 7 is connected to the third heat exchange inlet 45 through the liquid oxygen pump 6, and the third heat exchange outlet 46 is used to connect to the user's oxygen pipeline network. The liquid oxygen in the liquid oxygen storage tank 7 uses cold energy for liquid air preparation through the heat exchanger 4.

[0029] A throttle valve V1 is provided between the first heat exchange outlet 42 and the liquid-air storage tank 5 , and a throttle valve V2 is provided between the first heat exchange outlet 42 and the second heat exchange inlet 43 .

[0030] The air compressor 1 in this embodiment adopts an oil-free water-lubricated screw machine, and the motor of the air compressor 1 adopts a permanent magnet motor and is equipped with a vector frequency converter.

[0031] This embodiment also includes a skid-mounted base and a control system, and the cold dryer 2 and the molecular sieve purifier 3 are an integrated structure. The air compressor 1, the cold dryer 2, the molecular sieve purifier 3, and the heat exchanger 4 are all arranged on the skid-mounted base. The air compressor 1, the cold dryer 2, the molecular sieve purifier 3, the heat exchanger 4, the liquid air storage tank 5, the liquid oxygen pump 6, and the liquid oxygen storage tank 7 are all connected to the control system and controlled by the control system.

[0032] The miniaturized liquid nitrogen cold recovery device in this embodiment is used to vaporize 1.0 MPa liquid oxygen, and the corresponding heat source air pressure is 2.1-2.3 MPa.

[0033] The air is pressurized to 2.1-2.3 MPa by the air compressor 1 and enters the cold dryer 2 for further cooling, and then enters the molecular sieve purifier 3 to remove moisture, CO2 and impurities. The dry and clean air enters the heat exchanger 4 to be cooled and liquefied; the liquid oxygen from the liquid oxygen storage tank pressurized by the liquid oxygen pump 6 enters the heat exchanger 4, is vaporized and reheated, and then enters the user's oxygen pipeline network.

[0034] The liquid air after supercooling in the heat exchanger 4 is divided into two destinations. One part is throttled to normal pressure by the throttle valve V2 and then returns to the heat exchanger 4, and enters the molecular sieve purifier 3 as the analysis gas after vaporization and reheating; the remaining part is sent to the liquid air storage tank as the liquid air product after being decompressed by the throttle valve V1; the liquid air vapor in the liquid air storage tank merges with the air throttled to normal pressure and enters the heat exchanger 4 for reheating, and also enters the molecular sieve purifier 3 as the analysis gas.

[0035] In this embodiment, the air is pressurized to 2.1-2.3MPa by the air compressor 1, and the interface diameter is DN65. Liquid oxygen is taken out from the user's liquid oxygen pump 6 and sent to the heat exchanger 4, with a junction pressure of about 1.0MPa and an interface diameter of DN25. Normal pressure air is taken out from the heat exchanger 4 and sent to the molecular sieve purifier 3 with a junction pressure of about 15kPa and an interface diameter of DN40. Liquid air is taken out from the heat exchanger 4 and sent to the liquid air storage tank, with a junction pressure of about 0.2MPa and an interface diameter of DN25. Oxygen is taken out from the heat exchanger 4 and sent to the user's oxygen main pipe, with a junction pressure of about 1.0MPa and an interface diameter of DN80.

[0036] The raw materials used in this utility model: liquid oxygen: 500Nm 3 / h (converted to gas), 1.0MPa; air: 630Nm 3 / h, 2.1~2.3MPa. Obtained product: Liquid air: 549Nm 3 / h (converted to gas); atmospheric pressure air (analytical gas): 81m 3 / h, 15kPa; oxygen: 500Nm 3 / h, 1.0MPa.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the utility model.

Claims

1. A miniaturized liquid oxygen cooling capacity recovery device, characterized in that: It includes an air compressor, a cold dryer, a molecular sieve purifier, a heat exchanger, a liquid air storage tank, a liquid oxygen pump, and a liquid oxygen storage tank; the molecular sieve purifier is provided with two groups of inlets and outlets, namely, an air inlet and an air outlet, and a desorption gas inlet and a desorption gas outlet; the heat exchanger is provided with three groups of inlets and outlets, namely, a first heat exchange inlet and a first heat exchange outlet, a second heat exchange inlet and a second heat exchange outlet, and a third heat exchange inlet and a third heat exchange outlet; The air compressor, the cold dryer, and the molecular sieve purifier are connected in series in sequence, the cold dryer is connected to the air inlet of the molecular sieve purifier, the air outlet of the molecular sieve purifier is connected to the first heat exchange inlet, the first heat exchange outlet is divided into two paths, one path is connected to the liquid air storage tank, and the other path is connected to the second heat exchange inlet, and the second heat exchange outlet is connected to the analytical gas inlet; The liquid oxygen storage tank is connected to the third heat exchange inlet through a liquid oxygen pump, and the third heat exchange outlet is used to connect to the user's oxygen pipeline network. The liquid oxygen in the liquid oxygen storage tank uses cold energy for liquid air preparation through a heat exchanger.

2. The miniaturized liquid oxygen cooling capacity recovery device according to claim 1 is characterized in that: A throttle valve is arranged between the first heat exchange outlet and the second heat exchange inlet, and between the first heat exchange outlet and the liquid-air storage tank.

3. The miniaturized liquid oxygen cooling capacity recovery device according to claim 1 is characterized in that: The air compressor adopts an oil-free water-lubricated screw machine, and the motor of the air compressor adopts a permanent magnet motor and is equipped with a vector frequency converter.

4. The miniaturized liquid oxygen cooling capacity recovery device according to claim 1 is characterized in that: The cold dryer and the molecular sieve purifier are an integrated structure.

5. The miniaturized liquid oxygen cooling capacity recovery device according to claim 1 is characterized in that: It also includes a skid-mounted base, on which the air compressor, cold dryer, molecular sieve purifier and heat exchanger are all arranged.

6. The miniaturized liquid oxygen cooling capacity recovery device according to claim 1 is characterized in that: The third heat exchange inlet is located at the lower middle portion of the heat exchanger so that the liquid oxygen does not flow through the bottom of the heat exchanger.

7. The miniaturized liquid oxygen cooling capacity recovery device according to claim 1 is characterized in that: It also includes a control system. The air compressor, cold dryer, molecular sieve purifier, heat exchanger, liquid air storage tank, liquid oxygen pump, and liquid oxygen storage tank are all connected to the control system and controlled by the control system.

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