CO2 cold-carrying refrigerating device arranged in tunnel and capable of shortening construction period

Abstract

The utility model relates to a CO2 cold-carrying refrigerating device which is arranged in a tunnel and can shorten the construction period. The problems that in the background technology, due to the fact that equipment is too wide and too high, when the equipment is placed in a tunnel, synchronous construction with other working procedures cannot be achieved, the construction period of a whole project is prolonged, and the construction cost is increased are solved. According to the technical scheme, the device is characterized in that the device is divided into two or more modules, the modules are connected through a plurality of pipelines, and the modules comprise a compression condensing unit and a compressor, an oil separator, an oil cooler, a condenser, an economizer and a first throttling valve in accessory equipment of the compression condensing unit; the plurality of modules further comprise a CO2 cold-carrying auxiliary machine unit and a condensation evaporation circulating barrel, a CO2 refrigeration pump and a throttle valve II in accessory equipment of the CO2 cold-carrying auxiliary machine unit; and the condensation evaporator is arranged in the CO2 low-pressure circulating barrel to form a condensation and evaporation circulating barrel with an integrated structure. The method is suitable for stratum freezing construction in the tunnel.

Description

Technical Field

[0001] The utility model belongs to the refrigeration technology, and specifically relates to a CO 2 cold-carrier refrigeration device that can be placed in a tunnel to shorten the construction period. Background Technique

[0002] At present, the existing ground freezing technologies in the industry are divided into three types: brine freezing, liquid nitrogen freezing, and low-temperature carbon dioxide freezing. Among them, at similar costs, the freezing efficiency of low-temperature carbon dioxide is the highest. In the ground freezing of tunnels, the invention patent with the application number 202210450347.0 discloses "A Carbon Dioxide Cold-Carrier Unit for an Artificial Ground Freezing System". The problems existing in this cold-carrier unit are as follows: First, it is an integral device, and the compressor, water-cooled condenser, and carbon dioxide liquid storage tank are placed side by side in the width direction of the device, so the overall device is too wide. Second, the condensing evaporator and the carbon dioxide liquid storage tank used are two separate devices. Due to the need for gravity liquid drainage, the condensing evaporator must be placed above the carbon dioxide liquid storage tank, so the device will be very high. If the height is reduced, only the height between the CO 2 refrigeration pump and the CO 2 liquid storage tank can be reduced, which will greatly reduce the safe net positive suction head of the pump, and the pump is very likely to generate cavitation phenomenon, posing a great safety hazard to the CO 2 refrigeration pump; the utility model patent with the application number 201821887117.6 discloses "NH 3 / CO 2 Freezing Device". The problems existing in this freezing device are as follows: First, although this device is made in a split form in the length direction, the oil separator, oil cooler, and CO 2 collector are placed side by side in the width direction of the device, so the overall device is too wide. Second, the CO 2 liquefier (i.e., condensing evaporator) and the CO 2 collector (i.e., carbon dioxide liquid storage tank) of these two devices are also placed one above the other, and the height of the device will be very high. The devices in the above two patents will occupy a very wide passage when placed in the tunnel as a whole, which will affect the construction of other processes and cannot be constructed synchronously with other processes. Only after other processes in the tunnel are completed can the ground freezing be carried out finally. Generally, the time for ground freezing is very long, which will cause problems such as the extension of the construction period of the entire project and the increase in construction costs. Content of the Utility Model

[0003] The purpose of the utility model is to propose a CO 2A secondary refrigerant refrigeration device is provided to solve the problems in the background technology: due to the excessive width and height of the equipment, when placed in a tunnel, it will occupy a very wide passageway, affecting the construction of other processes and making it impossible to synchronize with other processes, resulting in an extended construction period and increased construction costs for the entire project. The technical solution adopted to solve this technical problem is: a CO that can shorten the construction period when placed in a tunnel 2 A secondary refrigerant refrigeration device, in which the refrigeration system is as follows: the refrigerant cycle is: the exhaust port of the compressor is sequentially connected to the oil separator, condenser, ports B and C of the economizer, throttle valve II, ports G and H of the condensation evaporation circulation barrel, and then returns to the suction port of the compressor through the pipeline. Port A in the pipeline is sequentially connected to throttle valve I, ports D and E of the economizer, and then returns to the gas supplement port of the compressor through the pipeline; CO 2 The secondary refrigerant cycle is: port I of the condensation evaporation circulation barrel is sequentially connected to CO 2 the refrigeration pump and the terminal evaporator outside this device, and then returns to port J of the condensation evaporation circulation barrel; the oil cycle is: the oil outlet of the oil separator is connected to the oil cooler through the pipeline and then returns to the oil inlet of the compressor. Its characteristics are: the device is divided into two or more modules, and the modules are connected by several pipelines. The several modules include: the compressor, oil separator, oil cooler, condenser, economizer, and throttle valve I in the compression condensation unit and its auxiliary equipment; the several modules also include: CO 2 the secondary refrigerant auxiliary unit and its auxiliary equipment, including the condensation evaporation circulation barrel, CO 2 the refrigeration pump, and throttle valve II; the condensation evaporator is placed in the 2 low-pressure circulation barrel to form an integrated condensation evaporation circulation barrel. Among them, the width of each module is 1 - 2 meters, and the height is 2 - 3 meters. When the condensation evaporation circulation barrel is a shell-and-tube type condensation evaporation circulation barrel, the equipment is provided with a liquid inlet, left tube sheet, cylinder body, heat exchange tubes, gas inlet, right tube sheet, gas outlet, left liquid cavity, liquid outlet, and right gas cavity; a liquid storage space is provided at the bottom of the cylinder body. When the condensation evaporation circulation barrel is a plate-shell type condensation evaporation circulation barrel, the equipment is provided with a gas outlet, left head, cylinder body, plate core, gas inlet, right head, liquid inlet, and liquid outlet; a liquid storage space is provided at the bottom of the cylinder body. The liquid supply method on the refrigeration side of the condensation evaporation circulation barrel is either direct expansion liquid supply or pump liquid supply. The compressor is either a single-stage compressor or a single-machine two-stage compressor. The number of compressors is single or multiple. The economizer is either dry type, full liquid type, or flash tank type. When the compressor is selected as a single-machine two-stage compressor, the low-pressure stage is either equipped with an economizer or not. Each module in this refrigeration device is either arranged horizontally or vertically in a cross shaft or a vertical shaft. The refrigerant is either Freon or ammonia.

[0004] Port B of the economizer is the liquid inlet pipe orifice, port C of the economizer is the liquid outlet pipe orifice, port D of the economizer is the liquid inlet of the evaporation side, and port E of the economizer is the gas outlet of the evaporation side. Port G of the condensation-evaporation circulation barrel is the refrigerant inlet, port H of the condensation-evaporation circulation barrel is the refrigerant outlet, and port I of the condensation-evaporation circulation barrel is located in the 2 liquid phase region on the secondary refrigerant side, and port J of the condensation-evaporation circulation barrel is located in the 2 gas phase region on the secondary refrigerant side.

[0005] The beneficial effects of the present utility model compared with the prior art are as follows: When the above technical solution is used for in-tunnel formation freezing construction, on the one hand, several modules include: a compressor, an oil separator, an oil cooler, a condenser, an economizer, and a first throttle valve in the compression condensation unit and its auxiliary equipment; it also includes: a 2 condensation-evaporation circulation barrel, a 2 refrigeration pump, and a second throttle valve in the secondary refrigerant auxiliary unit and its auxiliary equipment. The several modules are connected by several pipelines, making the device modular under the premise of complete equipment. The width of each module is not greater than 1.2 meters. Since the tunnel cross-section is circular and there are height restrictions when the equipment is placed on one side, the condensation-evaporator is now placed in the 2 low-pressure circulation barrel to form an integrated condensation-evaporation circulation barrel. Without arranging it in an up-and-down structure, the overall height of the module can be no higher than 2.5 meters. The 2 height between the refrigeration pump and the liquid level is not reduced, ensuring the safe operation of the pump. After the width and height of the equipment are reduced and it is placed on one side of the tunnel, the remaining passage width can reach 3.5 meters, greatly reducing the floor area of the equipment on one side of the tunnel. The formation freezing can be carried out synchronously with other processes in the tunnel without mutual influence, ultimately achieving the purpose of shortening the construction period of the entire project and reducing the construction cost; on the other hand: when the liquid supply method of the condensation-evaporation circulation barrel selects pump liquid supply, the problems of uneven liquid supply and poor heat exchange effect existing in the dry type can be solved; on the other hand: when the compressor selects a single-stage two-stage compressor, it is more energy-saving when the evaporation temperature is below -30°C; on the other hand: when the number of compressors is more than two, when one fails, there is still one that can continue to work, and the on-site freezing equipment does not need to stop, and the formation freezing work can continue; on the other hand, when the economizer selects the flash tank form, the temperature of the refrigerant liquid is lower and the economy of the system is better; on the other hand, this refrigeration device can be applied in different fields. According to the actual application occasion and the on-site installation size, it can be selected to be arranged horizontally or vertically in the cross shaft or vertically in the vertical shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a schematic structural diagram of two modules of the present utility model. Figure 2 is Figure 1 left view ofFigure 3 It is a schematic diagram of the pipelines of two modules of the present utility model. Figure 4 It is a diagram showing the equipment of the present utility model in place in a tunnel. Figure 5 It is a schematic structural diagram of three modules of the present utility model. Figure 6 It is a schematic diagram of the pipelines of three modules of the present utility model. Figure 7 It is a schematic diagram of the shell-and-tube condensation-evaporation circulation barrel in the present utility model. Figure 8 It is a schematic diagram of the plate-shell condensation-evaporation circulation barrel in the present utility model. Detailed implementation manners

[0007] Example 1: Refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 7 , a CO 2 cold-carrier refrigeration device that can shorten the construction period when placed in a tunnel. Among them, the refrigeration system is as follows: the refrigerant circulation is: the exhaust port of the compressor 4 is connected in sequence through pipelines to the oil separator 3, the condenser 1, the ports B and C of the economizer 6, the throttle valve II 7, and the ports G and H of the condensation-evaporation circulation barrel 8 and returns to the suction port of the compressor 4. The port A in the pipeline is connected in sequence through pipelines to the throttle valve I 5, the ports D and E of the economizer 6 and returns to the gas supplement port of the compressor 4; the CO 2 cold-carrier circulation is: the port I of the condensation-evaporation circulation barrel 8 is connected in sequence through pipelines to the CO 2 refrigeration pump 9, and the end evaporator 10 outside this device and returns to the port J of the condensation-evaporation circulation barrel 8; the oil circulation is: the oil outlet of the oil separator 3 is connected through a pipeline to the oil cooler 2 and returns to the oil inlet of the compressor 4. Its characteristics are: the device is divided into two modules, A and B. Module A includes: the compressor 4, the oil separator 3, the oil cooler 2, the condenser 1, the economizer 6, and the throttle valve I 5 in the compression-condensation unit and its auxiliary equipment. Module B includes: the condensation-evaporation circulation barrel 8, the CO 2 cold-carrier auxiliary unit and its auxiliary equipment, the refrigeration pump 9, and the throttle valve II 7. Module A and module B are arranged left and right in a cross well and are connected through several pipelines, enabling the device to achieve modularization on the premise of complete equipment; the condensation-evaporator 12 is placed in the CO 2 refrigeration pump 9, and the end evaporator 10 outside this device and returns to the port J of the condensation-evaporation circulation barrel 8; the oil circulation is: the oil outlet of the oil separator 3 is connected through a pipeline to the oil cooler 2 and returns to the oil inlet of the compressor 4. Its characteristics are: the device is divided into two modules, A and B. Module A includes: the compressor 4, the oil separator 3, the oil cooler 2, the condenser 1, the economizer 6, and the throttle valve I 5 in the compression-condensation unit and its auxiliary equipment. Module B includes: the condensation-evaporation circulation barrel 8, the CO 2Inside the low-pressure circulation barrel 11, there is a condensation-evaporation circulation barrel 8 made into an integral structure. Each module has a width of 1.2 meters and a height of 2.5 meters. It is placed on one side inside the tunnel, and the remaining passage width can reach 3.5 meters, so that the ground freezing can be carried out synchronously with other processes inside the tunnel without mutual influence. The condensation-evaporation circulation barrel 8 is a shell-and-tube condensation-evaporation circulation barrel, and on this equipment, there are a liquid inlet A1, a left tube sheet A2, a cylinder body A3, heat exchange tubes A4, an air inlet A5, a right tube sheet A6, an air outlet A7, a left liquid cavity A8, a liquid outlet A9, and a right air cavity A10. There is a liquid storage space A11 at the bottom of the cylinder body. The liquid supply method on the refrigeration side of the condensation-evaporation circulation barrel 8 is direct expansion liquid supply. The compressor 4 is a single-stage compressor. The number of compressors 4 is one unit. The economizer 6 is dry type. The refrigerant is Freon. The B port of the economizer is the liquid inlet pipe orifice, the C port of the economizer is the liquid outlet pipe orifice, the D port of the economizer is the liquid inlet of the evaporation side, and the E port of the economizer is the air outlet of the evaporation side. The G port of the condensation-evaporation circulation barrel is the refrigerant inlet, the H port of the condensation-evaporation circulation barrel is the refrigerant outlet, and the I port of the condensation-evaporation circulation barrel is located in the CO 2 liquid phase region of the secondary refrigerant side, and the J port of the condensation-evaporation circulation barrel is located in the CO 2 gas phase region of the secondary refrigerant side.

[0008] Example 2: Refer to Figure 2 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 8 , a CO 2 secondary refrigerant refrigeration device placed inside the tunnel that can shorten the construction period, where the refrigeration system is: the refrigerant cycle is: the exhaust port of the compressor 4 is connected in sequence through pipelines to the oil separator 3, the condenser 1, the B port and C port of the economizer 6, the throttle valve two 7, the L port and M port of the low-pressure circulation barrel 13, the refrigeration pump 14, the G port and H port of the condensation-evaporation circulation barrel 8, the N port and O port of the low-pressure circulation barrel 13, and returns to the suction port of the compressor 4. The A port in the pipeline is connected in sequence through pipelines to the throttle valve one 5, the D port and E port of the economizer 6 and returns to the gas supplement port of the compressor 4; the CO 2 secondary refrigerant cycle is: the I port of the condensation-evaporation circulation barrel 8 is connected in sequence through pipelines to the CO 2 refrigeration pump 9, the end evaporator 10 outside this device and returns to the J port of the condensation-evaporation circulation barrel 8; the oil cycle is: the oil outlet of the oil separator 3 is connected through a pipeline to the oil cooler 2 and returns to the oil inlet of the compressor 4. Its characteristics are: this device is divided into three modules. Module A includes: the compressor 4, the oil separator 3, the oil cooler 2, the condenser 1, the economizer 6, and the throttle valve one 5 in the compression condensation unit and its auxiliary equipment. Module B includes: the CO 2 secondary refrigerant auxiliary unit and its auxiliary equipment, the condensation-evaporation circulation barrel 8, the CO 2Refrigeration pump 9, throttle valve two 7. Module C includes: low-pressure circulation drum 13 and refrigeration pump 14 in the barrel pump unit and its auxiliary equipment. Modules A, B, and C are arranged horizontally in the cross well and connected by several pipelines, enabling modularization of the device on the premise of complete equipment. Condensing evaporator 12 is placed in the CO 2 Low-pressure circulation drum 11, and the condensing evaporation circulation drum 8 made in an integral structure form. The width of each module is 1.1 meters and the height is 2.6 meters. It is placed on one side of the tunnel, and the remaining passage width can reach 3.5 meters, so that the ground freezing can be synchronized with other processes in the tunnel without mutual influence. When the condensing evaporation circulation drum 8 is a plate-shell type condensing evaporation circulation drum, the device is provided with an air outlet B1, a left head B2, a cylinder body B3, a plate core B4, an air inlet B5, a right head B6, a liquid inlet B7, and a liquid outlet B8. A liquid storage space B9 is provided at the bottom of the cylinder body. The liquid supply method on the refrigeration side of the condensing evaporation circulation drum 8 is pump liquid supply. The compressor 4 is a single-stage compressor. The number of compressors 4 is one unit. The economizer 6 is dry type. The refrigerant is Freon. The B port of the economizer is the liquid inlet pipe orifice, the C port of the economizer is the liquid outlet pipe orifice, the D port of the economizer is the liquid inlet of the evaporation side, and the E port of the economizer is the air outlet of the evaporation side. The L port of the low-pressure circulation drum is the liquid inlet of the refrigerant. The M port of the low-pressure circulation drum is located in the liquid phase area. The N port of the low-pressure circulation drum is located in the gas phase area at the air inlet end, and the O port of the low-pressure circulation drum is located in the gas phase area at the air outlet end. The G port of the condensing evaporation circulation drum is the liquid inlet of the refrigerant. The I port of the condensing evaporation circulation drum is located in the CO 2 Liquid phase area on the secondary refrigerant side. The H port of the condensing evaporation circulation drum is the air outlet of the refrigerant. The J port of the condensing evaporation circulation drum is located in the CO 2 Gas phase area on the secondary refrigerant side.

Claims

1. A CO2 cooling device placed in a tunnel to shorten the construction period, wherein the refrigeration system is: the refrigerant circulation is: the exhaust port of the compressor (4) is connected to the oil separator (3), the condenser (1), the B port and the C port of the economizer (6), the throttle valve 2 (7), the G port and the H port of the condensation evaporation circulation barrel (8) in sequence through a pipeline, and returns to the compressor (4) suction port, and the A port in the pipeline is connected to the throttle valve 1 (5), the D port and the E port of the economizer (6) in sequence through a pipeline to return to the compressor (4) air supply port; the CO2 cooling device circulation is: the I port of the condensation evaporation circulation barrel (8) is connected to the CO2 refrigeration pump (9) and the terminal evaporator (10) outside the device in sequence through a pipeline to return to the J port of the condensation evaporation circulation barrel (8); the oil circulation is: the oil outlet of the oil separator (3) is connected to the oil cooler (2) through a pipeline and returns to the oil inlet of the compressor (4), characterized in that: The device is divided into two or more modules, which are connected by a number of pipelines. The modules include: a compressor (4), an oil separator (3), an oil cooler (2), a condenser (1), an economizer (6), and a throttle valve 1 (5) in a compression condensing unit and its ancillary equipment; the modules also include: a condensing evaporation circulation barrel (8), a CO2 refrigeration pump (9), and a throttle valve 2 (7) in a CO2 cooling auxiliary unit and its ancillary equipment; the condensing evaporator (12) is placed in a CO2 low-pressure circulation barrel (11), making the condensing evaporation circulation barrel (8) an integrated structure.

2. According to claim 1, a CO2 cooling device placed in a tunnel to shorten the construction period is characterized by: Each module is 1 to 2 meters wide and 2 to 3 meters high.

3. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: The condensation evaporation circulation barrel (8) is a shell and tube type condensation evaporation circulation barrel, and is provided with a liquid inlet (A1), a left tube sheet (A2), a cylinder (A3), a heat exchange tube (A4), an air inlet (A5), a right tube sheet (A6), an air outlet (A7), a left liquid cavity (A8), a liquid outlet (A9), and a right air cavity (A10); and a liquid storage space (A11) is provided at the bottom of the cylinder.

4. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: The condensation evaporation circulation barrel (8) is a plate-shell type condensation evaporation circulation barrel, and is provided with an air outlet (B1), a left end cover (B2), a cylinder (B3), a plate core (B4), an air inlet (B5), a right end cover (B6), a liquid inlet (B7), and a liquid outlet (B8); and a liquid storage space (B9) is provided at the bottom of the cylinder.

5. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: The liquid supply method on the refrigeration side of the condensation evaporation circulation barrel (8) is either direct expansion liquid supply or pump liquid supply consisting of a low-pressure circulation barrel (13) and a refrigeration pump (14).

6. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: The compressor (4) is either a single-stage compressor or a single-unit two-stage compressor.

7. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: The number of compressors (4) is single or multiple.

8. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: The economizer (6) is either of the dry type, the flooded type, or the flash tank type.

9. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: Compressor (4) When a single two-stage compressor is selected, the low-pressure stage is either provided with an economizer or without an economizer.

10. A CO2 cooling device placed in a tunnel to shorten the construction period according to claim 1 or 2, characterized in that: Each module in this refrigeration device is either arranged left and right in a horizontal shaft, or arranged up and down in a vertical shaft.

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