Suction and emptying device and method for ammonia gas in transportation tank

Abstract

The invention discloses a suction and emptying device and method for ammonia gas in a transportation tank, and relates to the technical field of liquid ammonia tank overhaul, and the device comprises an absorption unit and a suction unit. The absorption unit comprises a recovery tank, a pipeline, a water source and the like, the recovery tank is communicated with the water source through the pipeline, and a valve and a water pump are arranged on the pipeline; the suction unit comprises an exhaust pipe, an exhaust fan and an air supply pipe which are communicated in sequence, the exhaust pipe is communicated with the transport tank access hole, and the air supply pipe is communicated with the bottom of the recovery tank. The method comprises the following steps: injecting water into the recovery tank, and primarily recovering ammonia gas by utilizing tank pressure; injecting water into the tank to dissolve ammonia gas into water to form ammonia water, and pumping the ammonia water into a recovery tank; connecting an exhaust pipe with an access hole, and opening a liquid opening valve and a gas ammonia discharge valve; finally, an exhaust fan is started to suck residual ammonia gas to reach the safety standard. The ammonia gas can be efficiently emptied, the environment pollution caused by direct emission is avoided, the cost and the operation complexity are reduced, resource recycling and structural design optimization are realized, and safe and reliable operation is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of liquid ammonia tank maintenance, and in particular to a device and method for sucking and emptying ammonia gas in a transport tank. Background Art

[0002] Tank trucks, also known as tank trucks, are specialized vehicles used to transport liquid or gas chemical products such as liquid ammonia. As an important chemical raw material, liquid ammonia is widely used in fertilizer, refrigeration and other industries. However, safety and environmental protection issues are particularly prominent during the transportation and storage of liquid ammonia.

[0003] According to the standards of the National Energy Administration, tank trucks as pressure vessels need to be cleaned and inspected regularly to ensure their safe operation. Before the annual inspection, ammonia often remains in the transport tank of the tank truck. Direct discharge not only pollutes the environment, but also poses safety hazards, especially posing a threat to the health of workers. Traditional treatment methods, such as the air purge method mentioned in patent CN104964159A, can remove some residual ammonia, but face many challenges in actual operation.

[0004] First, the closed structure of the tank truck leads to extremely low ventilation efficiency. Air purging is time-consuming and difficult to meet the needs of fast and efficient operations. Second, the air purging process requires additional compressed air equipment, which increases the complexity and cost of the operation. In addition, the storage and management of compressed air is also a major problem, further increasing the operational burden. Summary of the invention

[0005] The purpose of the present invention is to provide a device and method for sucking and emptying ammonia in a transport tank, so as to solve the problems existing in the above-mentioned prior art and realize the rapid dilution and removal of ammonia in the tank truck.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a device for sucking and emptying ammonia in a transport tank, comprising:

[0008] An absorption unit, the absorption unit comprising a recovery tank, a first pipeline, a second pipeline and a water source; the recovery tank is connected to the water source through a third pipeline, one end of the first pipeline is connected to the recovery tank, and the other end is used to communicate with the gas ammonia discharge valve at the bottom of the transport tank, one end of the second pipeline is connected to the water source, and the other end is used to communicate with the liquid valve at the bottom of the transport tank; a second water pump is provided on the second pipeline, and the second water pump is a two-way water pump; the second pipeline is also connected to the recovery tank through a third pipeline, and a first valve is provided on the third pipeline; a second valve is provided on the second pipeline, and the second valve is closer to the water source than the first valve;

[0009] The suction unit comprises an exhaust pipe, an exhaust fan and an air supply pipe which are connected in sequence, wherein one end of the exhaust pipe away from the exhaust fan is used to be connected to the inspection port of the transport tank; one end of the air supply pipe away from the exhaust fan is connected to the bottom of the recovery tank.

[0010] Preferably, it further comprises a solvent adding unit, the solvent adding unit comprises a solvent storage tank and a fourth pipeline, the solvent storage tank is connected with the recovery tank through the fourth pipeline, and the fourth pipeline is provided with a first water pump.

[0011] Preferably, ultrapure water produced by an ultrapure water production device is used as the water source.

[0012] Preferably, a distributor is fixedly provided at the bottom of the recovery tank, and the distributor is a transverse tube, and the transverse tube is provided with a plurality of discharge ports and a feed port, and the feed port is connected with the first pipeline.

[0013] Preferably, an ammonia concentration detection device is further provided in the recovery tank, and a discharge port is further provided on the recovery tank, and a discharge valve is provided at the discharge port.

[0014] The present invention also provides a method for sucking and emptying ammonia in a transport tank, based on the above-mentioned device for sucking and emptying ammonia in a transport tank, comprising the following steps:

[0015] (1) opening the first valve and the second valve, and injecting water into the recovery tank; then closing the first valve and the second valve, and opening the gas ammonia discharge valve, using the pressure in the transport tank to discharge part of the ammonia gas into the recovery tank through the first pipeline, until the pressure in the transport tank is consistent with the atmospheric pressure, and closing the gas ammonia discharge valve to complete the initial recovery;

[0016] (2) Opening the second valve, the liquid-passing valve and the second water pump, injecting water into the transport tank until the liquid level in the transport tank reaches half of the height of the transport tank, and then closing the gaseous ammonia discharge valve and the second water pump; after standing for 1 to 2 hours, the ammonia gas in the transport tank is dissolved in water to form ammonia water, opening the liquid-passing valve, the second water pump and the first valve, pumping all the ammonia water into the recovery tank, and then closing the liquid-passing valve, the second water pump and the first valve;

[0017] (3) sealingly connecting one end of the exhaust pipe away from the exhaust fan to the inspection port of the transport tank, and opening the liquid valve and the gas ammonia discharge valve to allow external air to enter the transport tank through the liquid valve and the gas ammonia discharge valve;

[0018] (4) Turn on the exhaust fan to pump the remaining ammonia in the transport tank into the recovery tank until the ammonia concentration in the transport tank reaches the safety standard.

[0019] Preferably, after performing step (4), step (5) is further performed:

[0020] The first water pump is turned on to pump the solvent rich in magnesium ions and phosphate ions in the solvent storage tank into the recovery tank, so that magnesium ammonium phosphate is generated in the recovery tank. After the reaction is completed, the water in the recovery tank is discharged, and the magnesium ammonium phosphate in the recovery tank is taken out.

[0021] Compared with the prior art, the present invention has achieved the following technical effects:

[0022] First, through the cooperation of the exhaust fan of the suction unit and the recovery tank, the ammonia in the transport tank can be quickly pumped into the recovery tank, which greatly improves the ammonia emptying speed and meets the requirements of fast and efficient operation. At the same time, the multi-step treatment method, including the use of the pressure in the tank for initial recovery, water injection to dissolve ammonia water, and the exhaust fan to suck the remaining ammonia, ensures the efficient emptying of ammonia.

[0023] Secondly, it effectively avoids direct emission of ammonia, greatly reducing pollution to the environment and threats to the health of workers. The centralized treatment of recovery tanks makes the treatment of ammonia safer and more reliable, reducing safety risks.

[0024] Furthermore, compared with the traditional air purging method, the present application does not require additional compressed air equipment, reduces equipment investment and operation steps, and reduces costs and operational difficulties. Ultrapure water as a water source not only improves the dissolution effect of ammonia, but also reduces the cost of obtaining water sources.

[0025] In addition, the recycling of resources is achieved. By adding a solvent rich in magnesium ions and phosphate ions to the recovery tank, magnesium ammonium phosphate is generated, which provides a way for the reuse of resources and improves the utilization value of resources.

[0026] Finally, the distributor in the recovery tank allows ammonia gas to contact water evenly, improving dissolution efficiency; the ammonia concentration detection device facilitates real-time monitoring of treatment progress; and the setting of a two-way water pump enhances the practicality of the device.

[0027] In summary, the device and method for sucking and emptying ammonia in a transport tank of the present invention have significant technical effects in terms of efficient emptying of ammonia, environmental protection and safety, cost reduction, resource recycling and utilization, and structural optimization, and provide an advanced and reliable solution for the field of liquid ammonia tank maintenance technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic structural diagram of the device for sucking and emptying ammonia in a transport tank of the present invention;

[0030] In the figure: 100, a suction and emptying device for ammonia gas in a transport tank;

[0031] 1. Transport tank; 2. Inspection port; 3. Exhaust pipe; 4. Exhaust fan; 5. First water pump; 6. First valve; 7. Second valve; 8. Recovery tank; 9. Ammonia concentration detection device; 10. Distributor; 11. Liquid valve; 12. Gas ammonia discharge valve; 13. Second water pump; 14. First pipeline; 15. Second pipeline; 16. Ultrapure water production device; 17. Solvent storage tank; 18. Tank truck. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] The purpose of the present invention is to provide a device and method for sucking and emptying ammonia in a transport tank, so as to solve the problems existing in the above-mentioned prior art and realize the rapid dilution and removal of ammonia in the tank truck.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] Embodiment 1

[0036] like Figure 1 As shown, this embodiment provides a device 100 for sucking and emptying ammonia in a transport tank, comprising:

[0037] The absorption unit includes a recovery tank 8, a first pipeline 14, a second pipeline 15 and a water source; the recovery tank 8 is connected to the water source through a third pipeline, one end of the first pipeline 14 is connected to the recovery tank 8, and the other end is used to communicate with the gas ammonia discharge valve 12 at the bottom of the transport tank 1, and one end of the second pipeline 15 is connected to the water source, and the other end is used to communicate with the liquid valve 11 at the bottom of the transport tank 1; the second pipeline 15 is provided with a second water pump 13, and the second water pump 13 is a two-way water pump; the second pipeline 15 is also connected to the recovery tank 8 through a third pipeline, and the third pipeline is provided with a first valve 6; the second pipeline 15 is provided with a second valve 7, and the second valve 7 is closer to the water source than the first valve 6; the transport tank 1 is usually arranged on a tank truck 18;

[0038] The suction unit includes an exhaust pipe 3, an exhaust fan 4 and an air supply pipe which are connected in sequence. The end of the exhaust pipe 3 away from the exhaust fan 4 is used to be connected with the inspection port 2 of the transport tank 1; the end of the air supply pipe away from the exhaust fan 4 is connected with the bottom of the recovery tank 8.

[0039] Preferably, a solvent adding unit is further included, the solvent adding unit includes a solvent storage tank 17 and a fourth pipeline, the solvent storage tank 17 is connected to the recovery tank 8 through the fourth pipeline, and the fourth pipeline is provided with a first water pump 5. The solvent storage tank 17 is used to store a solvent rich in magnesium ions and phosphate ions, and by adding a solvent rich in magnesium ions and phosphate ions to the recovery tank 8, the solvent reacts with the ammonia water in the recovery tank 8 to generate magnesium ammonium phosphate, which provides a way for the reuse of resources and improves the utilization value of resources.

[0040] The working principle of the ammonia suction and emptying device 100 in the transport tank of this embodiment is as follows:

[0041] After connecting the exhaust pipe 3 to the inspection port 2 of the transport tank 1, open the liquid valve 11 and the gas ammonia discharge valve 12 to allow the outside air to enter the transport tank 1 through the liquid valve 11 and the gas ammonia discharge valve 12, and then turn on the exhaust fan 4, and use the exhaust fan 4 to continuously extract the remaining ammonia in the transport tank 1 until its concentration drops below the safety standard, thereby ensuring the safety of subsequent operations; the exhaust fan 4 sends the extracted ammonia into the recovery tank 8 for recovery.

[0042] In the optional scheme of this embodiment, it is more preferred to use ultrapure water produced by the ultrapure water production device 16 as the water source, and the second pipeline 15 is connected to the ultrapure water outlet of the ultrapure water production device 16. The ultrapure water contains almost no impurities, such as minerals, organic matter, microorganisms, suspended particles, etc. This means that when dissolving ammonia, the solubility of ammonia will not be affected by other substances in the water, thereby ensuring the purity and stability of ammonia water; using ultrapure water to prepare ammonia water can obtain a higher purity product; the high purity of ultrapure water means that its dissolving ability is stronger, especially when dissolving gases such as ammonia that are easily soluble in water, a higher solubility can be achieved. Although ammonia already has a high solubility in water, the use of ultrapure water can theoretically be closer to the theoretical maximum solubility.

[0043] In the optional scheme of this embodiment, it is more preferred that a distributor 10 is fixedly provided at the bottom of the recovery tank 8, and the distributor 10 is a horizontal tube, on which are provided a plurality of discharge ports and a feed port, and the feed port is connected to the first pipeline 14; the design of the distributor 10 in the recovery tank 8 improves the dissolution efficiency of ammonia, making ammonia recovery more efficient.

[0044] The recovery tank 8 is also provided with an ammonia concentration detection device 9, and the recovery tank 8 is also provided with a discharge port, and a discharge valve is provided at the discharge port. The ammonia concentration detection device 9 can detect the concentration of the ammonia in the recovery tank 8 in real time.

[0045] It is worth noting that the ultrapure water production device 16 and the ammonia concentration detection device 9 are both commercially available products well known in the art, and their specific structures and working principles will not be described in detail in this embodiment.

[0046] Embodiment 2

[0047] This embodiment provides a method for sucking and emptying ammonia gas in a transport tank 1, based on the device 100 for sucking and emptying ammonia gas in a transport tank of the first embodiment, comprising the following steps:

[0048] (1) Open the first valve 6 and the second valve 7, and inject water into the recovery tank 8; then close the first valve 6 and the second valve 7, and open the gas ammonia discharge valve 12, and use the pressure in the transport tank 1 to discharge part of the ammonia gas into the recovery tank 8 through the first pipeline 14 until the pressure in the transport tank 1 is consistent with the atmospheric pressure, and then close the gas ammonia discharge valve 12 to complete the initial recovery;

[0049] (2) Open the second valve 7, the liquid-passing valve 11 and the second water pump 13, and inject water into the transport tank 1 until the liquid level in the transport tank 1 reaches half of the height of the transport tank 1, and then close the gaseous ammonia discharge valve 12 and the second water pump 13; after standing for h to h, the ammonia gas in the transport tank 1 is dissolved in water to form ammonia water, open the liquid-passing valve 11, the second water pump 13 and the first valve 6, and pump all the ammonia water into the recovery tank 8, and then close the liquid-passing valve 11, the second water pump 13 and the first valve 6;

[0050] (3) The end of the exhaust pipe 3 away from the exhaust fan 4 is sealed and connected to the inspection port 2 of the transport tank 1, and the liquid valve 11 and the gas ammonia discharge valve 12 are opened to allow external air to enter the transport tank 1 through the liquid valve 11 and the gas ammonia discharge valve 12;

[0051] (4) Turn on the exhaust fan 4 to pump the remaining ammonia in the transport tank 1 into the recovery tank 8 until the ammonia concentration in the transport tank 1 reaches the safety standard.

[0052] In the optional solution of this embodiment, it is more preferred that after performing step (4), step (5) is further performed:

[0053] Turn on the first water pump 5 and pump the solvent rich in magnesium ions and phosphate ions in the solvent storage tank 17 into the recovery tank 8. Since ammonia gas dissolves in water to generate ammonium ions, and the ammonium ions react with magnesium ions and phosphate ions to generate magnesium ammonium phosphate, magnesium ammonium phosphate is generated in the recovery tank 8 and precipitated at the bottom of the recovery tank 8. After the reaction is completed, the water in the recovery tank 8 is discharged, and the magnesium ammonium phosphate in the recovery tank 8 is taken out.

[0054] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A device for sucking and emptying ammonia in a transport tank, characterized in that: include: An absorption unit, the absorption unit comprising a recovery tank, a first pipeline, a second pipeline and a water source; The recovery tank is connected to the water source through a third pipeline, one end of the first pipeline is connected to the recovery tank, and the other end is used to communicate with the gas ammonia discharge valve at the bottom of the transport tank, and one end of the second pipeline is connected to the water source, and the other end is used to communicate with the liquid valve at the bottom of the transport tank; a second water pump is provided on the second pipeline, and the second water pump is a two-way water pump; the second pipeline is also connected to the recovery tank through a third pipeline, and a first valve is provided on the third pipeline; a second valve is provided on the second pipeline, and the second valve is closer to the water source than the first valve; The suction unit comprises an exhaust pipe, an exhaust fan and an air supply pipe which are connected in sequence, wherein one end of the exhaust pipe away from the exhaust fan is used to be connected to the inspection port of the transport tank; one end of the air supply pipe away from the exhaust fan is connected to the bottom of the recovery tank.

2. The device for sucking and emptying ammonia in a transport tank according to claim 1, characterized in that: It also includes a solvent adding unit, which includes a solvent storage tank and a fourth pipeline. The solvent storage tank is connected to the recovery tank through the fourth pipeline, and a first water pump is arranged on the fourth pipeline.

3. The device for sucking and emptying ammonia in a transport tank according to claim 2, characterized in that: Ultrapure water produced by an ultrapure water production device is used as the water source.

4. The device for sucking and emptying ammonia in a transport tank according to claim 3, characterized in that: A distributor is also fixedly arranged at the bottom of the recovery tank. The distributor is a transverse pipe. A plurality of discharge ports and a feed port are arranged on the transverse pipe. The feed port is communicated with the first pipeline.

5. The device for sucking and emptying ammonia in a transport tank according to claim 3, characterized in that: The recovery tank is also provided with an ammonia concentration detection device, and the recovery tank is also provided with a discharge port, and a discharge valve is provided at the discharge port.

6. A method for extracting and emptying ammonia in a transport tank, characterized in that: The device for sucking and emptying ammonia in a transport tank according to any one of claims 1 to 5 comprises the following steps: (1) opening the first valve and the second valve, and injecting water into the recovery tank; then closing the first valve and the second valve, and opening the gas ammonia discharge valve, using the pressure in the transport tank to discharge part of the ammonia gas into the recovery tank through the first pipeline, until the pressure in the transport tank is consistent with the atmospheric pressure, and closing the gas ammonia discharge valve to complete the initial recovery; (2) Opening the second valve, the liquid-passing valve and the second water pump, injecting water into the transport tank until the liquid level in the transport tank reaches half of the height of the transport tank, and then closing the gaseous ammonia discharge valve and the second water pump; after standing for 1 to 2 hours, the ammonia gas in the transport tank is dissolved in water to form ammonia water, opening the liquid-passing valve, the second water pump and the first valve, pumping all the ammonia water into the recovery tank, and then closing the liquid-passing valve, the second water pump and the first valve; (3) sealingly connecting one end of the exhaust pipe away from the exhaust fan to the inspection port of the transport tank, and opening the liquid valve and the gas ammonia discharge valve to allow external air to enter the transport tank through the liquid valve and the gas ammonia discharge valve; (4) Turn on the exhaust fan to pump the remaining ammonia in the transport tank into the recovery tank until the ammonia concentration in the transport tank reaches the safety standard.

7. The method for extracting and emptying ammonia gas in a transport tank according to claim 6, characterized in that: Based on the device for sucking and emptying ammonia in a transport tank according to claim 2, after performing step (4), step (5) is further performed: The first water pump is turned on to pump the solvent rich in magnesium ions and phosphate ions in the solvent storage tank into the recovery tank, so that magnesium ammonium phosphate is generated in the recovery tank. After the reaction is completed, the water in the recovery tank is discharged, and the magnesium ammonium phosphate in the recovery tank is taken out.

Images