Synthetic ammonia liquefying device

Abstract

The utility model relates to the technical field of synthetic ammonia liquefaction systems, in particular to a synthetic ammonia liquefaction device which comprises a gas storage tank, a first exhaust pipe is communicated and mounted at the bottom of the gas storage tank, a three-way pipe is arranged on the first exhaust pipe, a first gas return pipe is communicated and mounted on the front side of the three-way pipe, and the synthetic ammonia liquefaction device further comprises a recovery tank. The recovery tank is arranged on one side of the gas storage tank; wherein the bottom of the recovery tank is communicated with the first air return pipe; wherein the top of the recovery tank is communicated with the gas storage tank through a second gas return pipe. The liquid ammonia pressure relief device solves the problems that equipment breaks down due to the fact that the pressure of a liquid ammonia system is too high at the present stage, and liquid nitrogen waste is large after pressure relief is conducted.

Description

Technical Field

[0001] The utility model relates to the technical field of synthetic ammonia liquefaction systems, in particular to a synthetic ammonia liquefaction device. Background Art

[0002] Liquid ammonia is a colorless liquid with a strong pungent odor. As an important chemical raw material, ammonia is usually pressurized or cooled to obtain liquid ammonia for the convenience of transportation and storage. Liquid ammonia is easily soluble in water, and after dissolving in water, it forms ammonium ions NH4+ and hydroxide ions OH-, and the solution is alkaline. Liquid ammonia is mostly stored in pressure-resistant steel cylinders or steel tanks, and cannot coexist with substances such as acetaldehyde, acrolein, and boron. Liquid ammonia is widely used in industry, is corrosive and easily volatile, so its chemical accident rate is very high.

[0003] Liquid ammonia is an important product in the production of urea. During the normal production of liquid ammonia in the urea workshop, the medium-pressure ammonia pressure of the synthesis unit is 3.0MPa. It is known that the pressure control index of the liquid ammonia system of the urea unit is 2.3-2.5MPa, of which the safety valve tripping pressure is 2.98MPa. During normal operation, the pressure of the liquid ammonia system is controlled by the regulating valve FV4201, but when the liquid ammonia pump stops, the liquid ammonia loses its fluidity, and the pressure value of the liquid ammonia system is close to the pressure value of the medium-pressure ammonia, resulting in overpressure of the liquid ammonia system, the safety valve tripping, and a large waste of liquid nitrogen after the pressure is discharged.

[0004] Therefore, it is necessary to provide a synthetic ammonia liquefaction device to ensure that the liquid ammonia system is not over-pressurized, improve the reliability of stable operation of gaseous ammonia liquefaction, and when over-pressure liquid ammonia is discharged, the discharged liquid ammonia can be effectively recovered and reused. Utility Model Content

[0005] The utility model aims to provide a synthetic ammonia liquefaction device, which has the advantages of ensuring that the liquid ammonia system is not over-pressurized, improving the reliability of stable operation of gaseous ammonia liquefaction, and effectively recovering and reusing the discharged liquid ammonia when the over-pressurized liquid ammonia is discharged, thereby solving the problem that the current liquid ammonia system pressure is too high, causing equipment failure and a large waste of liquid nitrogen after pressure discharge.

[0006] To achieve the above object, the utility model provides the following technical solution: a synthetic ammonia liquefaction device, comprising a gas storage tank, the bottom of the gas storage tank is connected to a first exhaust pipe, the first exhaust pipe is provided with a three-way pipe, the front of the three-way pipe is connected to a first return air pipe, and also includes a recovery tank;

[0007] The recovery tank is located on one side of the gas storage tank;

[0008] The bottom of the recovery tank is connected to the first air return pipe;

[0009] The top of the recovery tank is connected to the gas storage tank through a second gas return pipe.

[0010] When using a synthetic ammonia liquefaction device in the technical solution, the air pressure in the recovery tank is kept low by a vacuum pump, and the regulating valve and the liquid ammonia pump are interlocked with each other. After the liquid ammonia pump stops, the regulating valve is automatically closed through interlock control to avoid leakage. The ammonia remaining in the first exhaust pipe can be directly discharged into the recovery tank by opening the exhaust valve under the action of the negative pressure in the recovery tank. After the gas in the gas storage tank is discharged, the recovery tank and the gas storage tank can be connected by opening the control valve, so that the ammonia in the recovery tank can be reused.

[0011] Preferably, a hole is opened on the top of the front side of the gas storage tank and is connected to a gas injection pipe, on which a gas injection valve is provided.

[0012] A hole is opened on the top of the front of the gas storage tank and connected to an air injection pipe, and an air injection valve is provided on the air injection pipe, so that air can be injected into the gas storage tank through the air injection pipe, and the opening and closing can be controlled by the air injection valve.

[0013] Preferably, a regulating valve and a liquid ammonia pump are provided on the first exhaust pipe from left to right, and the regulating valve and the liquid ammonia pump are electrically connected using an interlocking logic.

[0014] A regulating valve and a liquid ammonia pump are arranged on the first exhaust pipe from left to right, and the regulating valve and the liquid ammonia pump are electrically connected with an interlocking logic. By designing the interlocking logic between the regulating valve and the liquid ammonia pump, after the liquid ammonia pump stops, the regulating valve is automatically closed through interlocking control to avoid leakage.

[0015] Preferably, the three-way pipe is arranged on the first exhaust pipe on the side opposite to the regulating valve and the liquid ammonia pump.

[0016] By arranging the three-way pipe on the first exhaust pipe on the side opposite to the regulating valve and the liquid ammonia pump, the residual gas in the first exhaust pipe on the side opposite to the regulating valve and the liquid ammonia pump can be discharged.

[0017] Preferably, an exhaust valve is provided on the first air return pipe, and the exhaust valve adopts a manual valve structure design.

[0018] By providing an exhaust valve on the first air return pipe and adopting a manual valve structure design for the exhaust valve, after the exhaust valve is manually opened, the residual gas in the first exhaust pipe can enter the recovery tank through the first air return pipe.

[0019] Preferably, a hole is opened on the back of the recovery tank and connected to a second exhaust pipe, an air extraction pump is provided on the second exhaust pipe, and a pressure gauge is provided on the recovery tank.

[0020] A hole is opened on the back of the recovery tank and connected to a second exhaust pipe, and an air pump is arranged on the second exhaust pipe, so that negative pressure can be formed in the recovery tank through the air pump.

[0021] Preferably, a control valve is provided on the second air return pipe, and the control valve adopts a manual valve structure design.

[0022] By providing a control valve on the second air return pipe and adopting a manual valve structure design for the control valve, after the gas in the gas storage tank is discharged, the recovery tank and the gas storage tank can be connected by opening the control valve, so that the ammonia in the recovery tank can be reused.

[0023] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0024] The utility model provides a recovery tank and arranges the recovery tank on one side of the gas storage tank. At the same time, the bottom of the recovery tank is connected and installed with the first air return pipe, and the top of the recovery tank is connected and installed with the gas storage tank through the second air return pipe. When performing specific operations, the air pressure in the recovery tank is lowered by the vacuum pump, and the interlocking logic of the regulating valve and the liquid ammonia pump is designed. After the liquid ammonia pump stops, the regulating valve is automatically closed through interlocking control to avoid leakage. The ammonia remaining in the first exhaust pipe can be directly entered into the recovery tank by opening the exhaust valve under the action of the negative pressure in the recovery tank. After the gas in the gas storage tank is discharged, the recovery tank can be connected with the gas storage tank by opening the control valve, so that the ammonia in the recovery tank can be reused, thereby ensuring that the liquid ammonia system is not over-pressurized and improving the reliability of stable operation of gas-ammonia liquefaction. When the over-pressure liquid ammonia is discharged, the discharged liquid ammonia can be effectively recovered and reused. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the main structure of the utility model;

[0026] Figure 2 This is a front view structural schematic diagram of the utility model;

[0027] Figure 3 It is a rear view structural schematic diagram of the utility model.

[0028] In the figure: 1. gas storage tank; 2. first exhaust pipe; 3. liquid ammonia pump; 4. three-way pipe; 5. regulating valve; 6. exhaust valve; 7. first return air pipe; 8. air injection pipe; 9. air injection valve; 10. second return air pipe; 11. control valve; 12. recovery tank; 13. vacuum pump; 14. second exhaust pipe. DETAILED DESCRIPTION

[0029] 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.

[0030] Example

[0031] like Figure 1 , Figure 2 and Figure 3 As shown, the utility model provides an embodiment: a synthetic ammonia liquefaction device, including a gas storage tank 1, the bottom of the gas storage tank 1 is connected to a first exhaust pipe 2, the first exhaust pipe 2 is provided with a three-way pipe 4, the front of the three-way pipe 4 is connected to a first return air pipe 7, and also includes a recovery tank 12;

[0032] Specifically,

[0033] The recovery tank 12 is arranged on one side of the gas storage tank 1;

[0034] The bottom of the recovery tank 12 is connected to the first air return pipe 7;

[0035] The top of the recovery tank 12 is connected to the gas storage tank 1 through the second gas return pipe 10.

[0036] By setting a recovery tank 12, and setting the recovery tank 12 on one side of the gas storage tank 1, at the same time, the bottom of the recovery tank 12 is connected to the first return air pipe 7, and the top of the recovery tank 12 is connected to the gas storage tank 1 through the second return air pipe 10. When performing specific operations, the air pressure in the recovery tank 12 is low through the air pump 13, and the interlocking logic of the regulating valve 5 and the liquid ammonia pump 3 is designed. After the liquid ammonia pump 3 stops, the regulating valve 5 is automatically closed through the interlocking control to avoid leakage, and the ammonia remaining in the first exhaust pipe 2 is By opening the exhaust valve 6, the ammonia remaining in the first exhaust pipe 2 can directly enter the recovery tank 12 under the action of the negative pressure in the recovery tank 12, and after the gas in the gas storage tank 1 is discharged, the recovery tank 12 can be connected with the gas storage tank 1 by opening the control valve 11, so that the ammonia in the recovery tank 12 can be reused, thereby ensuring that the liquid ammonia system is not over-pressurized and improving the reliability of stable operation of gas ammonia liquefaction. When the over-pressure liquid ammonia is discharged, the discharged liquid ammonia can be effectively recovered and reused.

[0037] Furthermore, a hole is opened on the top of the front side of the gas storage tank 1 and connected to a gas injection pipe 8 , on which a gas injection valve 9 is provided.

[0038] A hole is opened on the top of the front of the gas storage tank 1 and connected to a gas injection pipe 8 , and a gas injection valve 9 is provided on the gas injection pipe 8 , so that gas can be injected into the gas storage tank 1 through the gas injection pipe 8 and the opening and closing can be controlled by the gas injection valve 9 .

[0039] Furthermore, a regulating valve 5 and a liquid ammonia pump 3 are provided on the first exhaust pipe 2 from left to right, and the regulating valve 5 and the liquid ammonia pump 3 are electrically connected using an interlocking logic.

[0040] By arranging a regulating valve 5 and a liquid ammonia pump 3 on the first exhaust pipe 2 from left to right, and electrically connecting the regulating valve 5 and the liquid ammonia pump 3 with an interlocking logic, and by designing the interlocking logic between the regulating valve 5 and the liquid ammonia pump 3, after the liquid ammonia pump 3 stops, the regulating valve 5 is automatically closed through interlocking control to avoid leakage.

[0041] Furthermore, the three-way pipe 4 is arranged on the first exhaust pipe 2 on the side opposite to the regulating valve 5 and the liquid ammonia pump 3 .

[0042] By arranging the three-way pipe 4 on the first exhaust pipe 2 on the side opposite to the regulating valve 5 and the liquid ammonia pump 3 , the residual gas in the first exhaust pipe 2 on the side opposite to the regulating valve 5 and the liquid ammonia pump 3 can be discharged.

[0043] Furthermore, the first air return pipe 7 is provided with an exhaust valve 6, and the exhaust valve 6 adopts a manual valve structure design.

[0044] By providing an exhaust valve 6 on the first air return pipe 7 and adopting a manual valve structure design for the exhaust valve 6 , after the exhaust valve 6 is manually opened, the residual gas in the first exhaust pipe 2 can enter the recovery tank 12 through the first air return pipe 7 .

[0045] Furthermore, a hole is opened on the back of the recovery tank 12 and connected to a second exhaust pipe 14 , an air pump 13 is provided on the second exhaust pipe 14 , and a pressure gauge is provided on the recovery tank 12 .

[0046] A second exhaust pipe 14 is installed by opening a hole at the back of the recovery tank 12 and connecting the second exhaust pipe 14 , and an air pump 13 is provided on the second exhaust pipe 14 , so that negative pressure can be formed in the recovery tank 12 through the air pump 13 .

[0047] Furthermore, a control valve 11 is provided on the second air return pipe 10, and the control valve 11 adopts a manual valve structure design.

[0048] By providing a control valve 11 on the second gas return pipe 10 and adopting a manual valve structure design for the control valve 11, after the gas in the gas storage tank 1 is discharged, the recovery tank 12 can be connected with the gas storage tank 1 by opening the control valve 11, so that the ammonia in the recovery tank 12 can be reused.

[0049] When the utility model is used, the air pressure in the recovery tank 12 is kept low by the vacuum pump 13, and the regulating valve 5 is designed with an interlocking logic with the liquid ammonia pump 3. After the liquid ammonia pump 3 stops, the regulating valve 5 is automatically closed through interlocking control to avoid leakage. The ammonia remaining in the first exhaust pipe 2 can be directly introduced into the recovery tank 12 by opening the exhaust valve 6 under the action of the negative pressure in the recovery tank 12. After the gas in the gas storage tank 1 is discharged, the recovery tank 12 can be connected with the gas storage tank 1 by opening the control valve 11, so that the ammonia in the recovery tank 12 can be reused.

[0050] 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 synthetic ammonia liquefaction device, comprising a gas storage tank (1), wherein a first exhaust pipe (2) is connected and installed at the bottom of the gas storage tank (1), a tee pipe (4) is provided on the first exhaust pipe (2), and a first return air pipe (7) is connected and installed at the front of the tee pipe (4), characterized in that: Also includes: A recovery tank (12) is arranged on one side of the gas storage tank (1); The bottom of the recovery tank (12) is connected to the first air return pipe (7). The top of the recovery tank (12) is connected to the gas storage tank (1) via a second gas return pipe (10).

2. A synthetic ammonia liquefaction device according to claim 1, characterized in that: The top of the front side of the gas storage tank (1) is opened and connected to a gas injection pipe (8), and a gas injection valve (9) is provided on the gas injection pipe (8).

3. A synthetic ammonia liquefaction device according to claim 1, characterized in that: A regulating valve (5) and a liquid ammonia pump (3) are arranged on the first exhaust pipe (2) from left to right, and the regulating valve (5) and the liquid ammonia pump (3) are electrically connected using an interlocking logic.

4. A synthetic ammonia liquefaction device according to claim 1, characterized in that: The three-way pipe (4) is arranged on the first exhaust pipe (2) on the side opposite to the regulating valve (5) and the liquid ammonia pump (3).

5. The synthetic ammonia liquefaction device according to claim 1, characterized in that: The first air return pipe (7) is provided with an exhaust valve (6), and the exhaust valve (6) adopts a manual valve structure design.

6. A synthetic ammonia liquefaction device according to claim 1, characterized in that: The recovery tank (12) has a hole on its back and is connected to a second exhaust pipe (14). The second exhaust pipe (14) is provided with an air pump (13). The recovery tank (12) is provided with a pressure gauge.

7. The synthetic ammonia liquefaction device according to claim 1, characterized in that: The second air return pipe (10) is provided with a control valve (11), and the control valve (11) is designed with a manual valve structure.

Images