Liquid level control device in ammonia gas condensation and recovery process

Abstract

The utility model relates to the technical field of ammonia gas condensation and recovery, in particular to a liquid level control device in an ammonia gas condensation and recovery process. According to the technical scheme, the recycling box comprises a recycling box body, a flash tank and a liquid level transmitter, a fixing box is fixed to the inner wall of the recycling box body, a supporting pipe is fixedly embedded into the inner wall of the fixing box, the outer end faces of the two sides of the supporting pipe communicate with fixing pipes, and the outer surfaces of the fixing pipes are in threaded connection with fixing valves; the outer surface of the supporting pipe is sleeved with a heat exchange pipe, the outer end faces of the two sides of the heat exchange pipe communicate with connecting pipes correspondingly, the outer surfaces of the connecting pipes are in threaded connection with connecting valves, the outer end face of one side of the recycling box body communicates with an air outlet pipe, the air outlet pipe communicates with a flash tank, and the flash tank is installed on the inner wall of the recycling box body. A partition plate is fixedly embedded into the inner wall of the flash tank, and liquid level transmitters are installed on the inner wall of the flash tank and one side of the partition plate. According to the utility model, the effect of long-period safe and stable operation of the ammonia press can be achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of ammonia condensation recovery, in particular to a liquid level control device for an ammonia condensation recovery process. Background Art

[0002] Saturated vapor pressure is the static gas pressure formed when a gas evaporates under a certain pressure at a certain temperature. Gases have different saturated vapor pressures at different temperatures. When the gas reaches the set temperature, their vaporization will change, and the degree of evaporation of the gas will also change greatly. The temperature of ammonia affects its saturated vapor pressure, which can be used to measure the evaporation of the gas. In most cases, the lower the saturated vapor pressure of ammonia, the lower the degree of evaporation of the gas. Therefore, if the temperature of ammonia is increased, the saturated vapor pressure will also increase.

[0003] The prior art discloses a kind of alkaline etching ammonia condensation recycling device of CN213172592U, including a recovery tower, an air inlet pipe is provided in the middle part of the left end of the recovery tower, a fan is provided at the inner top of the recovery tower, a driving pump is provided at the bottom of the recovery tower, an output pipe is provided at the output end of the driving pump, a circulation channel is provided at the inner upper part of the recovery tower, a plurality of atomizing nozzles are evenly provided along the circumference of the inner side of the circulation channel, a U-shaped tube is provided at the top of the recovery tower, and a drying filter element is detachably connected in the U-shaped tube. By providing a circulation channel and an atomizing nozzle, ammonia-containing waste gas flows upward through the action of a fan after entering the recovery tower from the air inlet pipe, and the atomizing nozzle sprays high-pressure atomized water, and the atomized water contacts the ammonia-containing waste gas, and the atomized water filters and adsorbs other impurities in the ammonia-containing waste gas, and cooperates with the cotton drying filter element in the U-shaped tube to absorb and filter the water vapor in the gas, so that the ammonia reaches the use standard.

[0004] The ammonia refrigeration system of Anyang Zhongying Fertilizer Co., Ltd. is one of the most important processes in the synthetic ammonia production process. Its function is to further reduce the temperature of the synthesis gas coming out of the ammonia synthesis tower by exchanging the liquid ammonia from the ammonia compressor storage tank through the shell side of the first and second ammonia coolers and the synthesis gas in the tube side. When the ammonia refrigeration system is operating normally, the liquid level of the first and second ammonia coolers should be strictly controlled to avoid the phenomenon of gas carrying liquid in the gas phase system of the ammonia cooler due to excessive liquid level. As a device for compressing gas, once the ammonia compressor carries liquid, it will cause damage to the compressor impeller and cause the ammonia compressor to jump. Utility Model Content

[0005] The utility model aims to provide a liquid level control device for an ammonia condensation recovery process to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a liquid level control device for an ammonia condensation recovery process, comprising a recovery box body, a flash tank and a liquid level transmitter, a fixed box is fixed to the inner wall of the recovery box body, and a support tube is embedded and fixed to the inner wall of the fixed box, a heat exchange tube is sleeved on the outer surface of the support tube, the flash tank is installed on the inner wall of the recovery box body, and a partition is embedded and fixed to the inner wall of the flash tank, and the liquid level transmitter is installed on the inner wall of the flash tank and one side of the partition.

[0007] When using the liquid level control device for ammonia condensation recovery process in the technical solution, after the liquid ammonia is evaporated and heated inside the fixed box, it can enter the flash tank through the outlet pipe. The flash tank is divided into three levels by a partition. The liquid level of the flash tank is controlled by a series of regulating valves, and the reverse flow material regulation is adopted. In this cascade regulation system, the flow regulation should first constitute a negative feedback regulation system to determine the positive and negative effects of the auxiliary regulating pipe. The positive and negative action options of the main and auxiliary regulating pipes are as follows: For the auxiliary flow circuit of the auxiliary regulating pipe, when the flow through the auxiliary regulating pipe increases, the regulating valve opening is required to decrease. Due to the air-open regulating valve, the auxiliary regulating pipe output is required to decrease, and the reverse action regulation method should be adopted. The working process is as follows: flow increases → level transmitter output increases → regulating pipe input (deviation) increases → regulation output decreases (reverse action) → regulating valve opening (air-open valve) decreases - flow decreases, the regulation direction is positive, and the liquid level of the first and second ammonia coolers is controlled to avoid the phenomenon of gas carrying liquid in the gas phase system of the ammonia cooler due to excessive liquid level, so as to achieve the effect of long-term safe and stable operation of the ammonia compressor.

[0008] Preferably, a workbench is fixed on the lower surface of the recycling box body, and supporting legs are welded on the lower surface of the workbench. By arranging the workbench and supporting legs on the lower surface of the recycling box body, it is convenient to support the recycling box body.

[0009] Preferably, the upper surface of the recycling box body is hingedly connected with a sealing cover, and a handle is welded on the upper surface of the sealing cover. By arranging the handle on the upper surface of the sealing cover, it is convenient to hold the handle to open or close the sealing cover.

[0010] Preferably, both outer end surfaces of the support tube are connected with fixed tubes, and the outer surface of the fixed tube is threadedly connected with a fixed valve. By arranging fixed tubes on both sides of the support tube, liquid ammonia can be easily introduced in and out.

[0011] Preferably, both outer end surfaces of the heat exchange tube are connected with connecting tubes, and the outer surface of the connecting tube is threadedly connected with a connecting valve. By arranging connecting tubes on both sides of the heat exchange tube, it is convenient for hot gas to enter and exit.

[0012] Preferably, an air outlet pipe is connected to the outer end surface of one side of the recovery box body, and the air outlet pipe is connected to the flash tank, and an air outlet valve is threadedly connected to the outer surface of the air outlet pipe. By arranging the air outlet pipe on one side of the recovery box body, it is convenient to arrange the air outlet pipe on one side of the recovery box body, so that ammonia gas can enter the flash tank.

[0013] Preferably, the interior of the partition is connected with a regulating pipe, and the outer surface of the regulating pipe is threadedly connected with a regulating valve. By arranging the regulating pipe on one side of the partition, it is convenient to adjust the liquid level.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] 1. The utility model achieves the effect of long-term safe and stable operation of the ammonia compressor by setting up a flash tank, a partition and a liquid level transmitter. After the liquid ammonia evaporates and heats inside the fixed box, it can enter the flash tank through the outlet pipe. The flash tank is divided into three levels by the partition. The liquid level of the flash tank is controlled by a series of regulating valves, and the reverse flow material regulation is adopted. In this cascade regulation system, the flow regulation should first constitute a negative feedback regulation system to determine the positive and negative effects of the auxiliary regulating pipe. The positive and negative action options of the main and auxiliary regulating pipes are as follows: For the auxiliary flow circuit of the auxiliary regulating pipe, when the flow through the auxiliary regulating pipe increases, the regulating valve opening is required to decrease. Due to the air-open regulating valve, the auxiliary regulating pipe output is required to decrease, and the reverse action regulation method should be adopted. The working process is as follows: flow increases → level transmitter output increases → regulating pipe input (deviation) increases → regulation output decreases (reverse action) → regulating valve opening (air-open valve) decreases - flow decreases, the regulation direction is positive, and the liquid level of the first and second ammonia coolers is controlled to avoid the phenomenon of gas carrying liquid in the gas phase system of the ammonia cooler due to excessive liquid level, so as to achieve the effect of long-term safe and stable operation of the ammonia compressor.

[0016] 2. The utility model achieves the effect of heating the evaporation of liquid ammonia by arranging a fixed box, a support tube and a heat exchange tube. A connecting tube is connected to the synthesis tower, and the fixed valve is opened so that the liquid ammonia can enter and exit the interior of the support tube through the fixed tube. The connecting valve is opened so that hot gas can enter and exit the heat exchange tube. The liquid ammonia flows inside the support tube for heat exchange, which can heat the evaporation of the liquid ammonia. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the main cross-sectional structure of the utility model;

[0018] Figure 2 It is a schematic diagram of the enlarged structure of the fixed box of the utility model;

[0019] Figure 3 This is a schematic diagram of the main cross-sectional structure of the fixed box of the utility model;

[0020] Figure 4It is a schematic diagram of the main cross-sectional structure of the flash tank of the utility model.

[0021] In the figure: 1. Sealing cover; 2. Handle; 3. Recovery box body; 4. Fixed box; 5. Workbench; 6. Support legs; 7. Flash tank; 8. Fixed valve; 9. Fixed pipe; 10. Air outlet valve; 11. Air outlet pipe; 12. Connecting valve; 13. Connecting pipe; 14. Support pipe; 15. Heat exchange pipe; 16. Regulating pipe; 17. Regulating valve; 18. Liquid level transmitter; 19. Partition. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] Embodiment 1

[0024] See also Figures 1 to 4 The utility model provides an embodiment: a liquid level control device for an ammonia condensation recovery process, comprising a recovery box body 3, a flash tank 7 and a liquid level transmitter 18, an outer end surface of one side of the recovery box body 3 is connected with an air outlet pipe 11, and the air outlet pipe 11 is connected with the flash tank 7, an outer surface of the air outlet pipe 11 is threadedly connected with an air outlet valve 10, the flash tank 7 is installed on the inner wall of the recovery box body 3, and a partition 19 is embedded and fixed on the inner wall of the flash tank 7, a liquid level transmitter 18 is installed on the inner wall of the flash tank 7 and one side of the partition 19, the interior of the partition 19 is connected with a regulating pipe 16, and the outer surface of the regulating pipe 16 is threadedly connected with a regulating valve 17.

[0025] Of course, as is well known to those skilled in the art, the recovery box body 3, fixed box 4, flash tank 7, air outlet pipe 11, support pipe 14, heat exchange tube 15, regulating valve 17 and liquid level transmitter 18 of the utility model also need to be provided with a power device to enable them to work normally, and as is well known to those skilled in the art, the provision of the power is commonplace, and they all belong to conventional means or common knowledge, and will not be elaborated here, and those skilled in the art can make any optional selections according to their needs or convenience.

[0026] Based on the liquid level control device of ammonia condensation recovery process of Example 1, after the liquid ammonia is evaporated and heated inside the fixed box 4, it can enter the flash tank 7 through the outlet pipe 11. The flash tank 7 is divided into three levels by the partition 19. The liquid level of the flash tank 7 is controlled by the series regulating valve 17, and the reverse flow material regulation is adopted. In this cascade regulation system, the flow regulation should first be made to constitute a negative feedback regulation system to determine the positive and negative effects of the auxiliary regulating pipe 16. The positive and negative action selections of the main and auxiliary regulating pipes 16 are as follows: For the auxiliary flow circuit of the auxiliary regulating pipe 16, when the flow through the auxiliary regulating pipe 16 increases, the opening of the regulating valve 17 is required to decrease. Due to the air-open regulating valve 17, the output of the auxiliary regulating pipe 16 is required to decrease, and the reverse action regulation method should be adopted. The working process is as follows: flow increases → the output of the liquid level transmitter 18 increases → the input (deviation) of the regulating pipe 16 increases → the regulation output decreases (reverse action) → the opening of the regulating valve 17 (air-open valve) decreases - the flow decreases, and the regulation direction is positive. By controlling the liquid level of the first and second ammonia coolers, the phenomenon of gas carrying liquid in the gas phase system of the ammonia cooler due to excessive liquid level is avoided, so as to achieve the effect of long-term safe and stable operation of the ammonia compressor.

[0027] Embodiment 2

[0028] like Figure 1-Figure 4 As shown, the utility model proposes a liquid level control device for an ammonia condensation recovery process. Compared with the first embodiment, the present embodiment further includes a recovery box body 3, a flash tank 7 and a liquid level transmitter 18. The upper surface of the recovery box body 3 is hingedly connected with a sealing cover 1, and a handle 2 is welded on the upper surface of the sealing cover 1, a workbench 5 is fixed on the lower surface of the recovery box body 3, and a supporting leg 6 is welded on the lower surface of the workbench 5, a fixed box 4 is fixed to the inner wall of the recovery box body 3, and a supporting tube 14 is embedded and fixed to the inner wall of the fixed box 4, the outer end surfaces on both sides of the support tube 14 are connected with a fixed tube 9, and the outer surface of the fixed tube 9 is threadedly connected with a fixed valve 8, the outer surface of the support tube 14 is sleeved with a heat exchange tube 15, the outer end surfaces on both sides of the heat exchange tube 15 are connected with a connecting tube 13, and the outer surface of the connecting tube 13 is threadedly connected with a connecting valve 12.

[0029] In this embodiment, a connecting pipe 13 is connected to the synthesis tower, and the fixed valve 8 is opened, so that liquid ammonia can enter and exit the support tube 14 through the fixed pipe 9. The connecting valve 12 is opened, and hot gas can enter and exit the heat exchange tube 15. The liquid ammonia flows inside the support tube 14 for heat exchange, which can heat the evaporation of the liquid ammonia.

[0030] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A liquid level control device for an ammonia condensation recovery process, comprising a recovery tank body (3), a flash tank (7) and a liquid level transmitter (18), characterized in that: A fixed box (4) is fixed to the inner wall of the recovery box body (3), and a support tube (14) is embedded and fixed to the inner wall of the fixed box (4), and a heat exchange tube (15) is sleeved on the outer surface of the support tube (14). The flash tank (7) is installed on the inner wall of the recovery box body (3), and a partition (19) is embedded and fixed to the inner wall of the flash tank (7). A liquid level transmitter (18) is installed on the inner wall of the flash tank (7) and one side of the partition (19).

2. The liquid level control device for ammonia condensation recovery process according to claim 1, characterized in that: A workbench (5) is fixed to the lower surface of the recovery box body (3), and supporting legs (6) are welded to the lower surface of the workbench (5).

3. The liquid level control device for ammonia condensation recovery process according to claim 1, characterized in that: The upper surface of the recovery box body (3) is hingedly connected to a sealing cover (1), and a handle (2) is welded to the upper surface of the sealing cover (1).

4. The liquid level control device for ammonia condensation recovery process according to claim 1, characterized in that: The outer end surfaces on both sides of the support tube (14) are both connected to the fixed tube (9), and the outer surface of the fixed tube (9) is threadedly connected to the fixed valve (8).

5. The liquid level control device for ammonia condensation recovery process according to claim 1, characterized in that: The outer end surfaces on both sides of the heat exchange tube (15) are connected to connecting tubes (13), and the outer surface of the connecting tube (13) is threadedly connected to a connecting valve (12).

6. The liquid level control device for ammonia condensation recovery process according to claim 1, characterized in that: An air outlet pipe (11) is connected to an outer end surface of one side of the recovery box body (3), and the air outlet pipe (11) is connected to the flash tank (7). An air outlet valve (10) is threadedly connected to the outer surface of the air outlet pipe (11).

7. The liquid level control device for ammonia condensation recovery process according to claim 1, characterized in that: The interior of the partition (19) is connected to a regulating pipe (16), and the outer surface of the regulating pipe (16) is threadedly connected to a regulating valve (17).

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