Flushing device for preventing crystal blockage

Abstract

The utility model relates to the technical field of chemical production, and particularly discloses a flushing device for preventing crystal blockage, which comprises a first regulating valve, a steam buffer tank, an electromagnetic valve, a gas purging pipe and a steam distribution station. Steam is introduced into the steam buffer tank by controlling the first regulating valve, and the pressure of the steam buffer tank is controlled and regulated by the first regulating valve; the steam distribution station is provided with an opening connecting pipe, the opening connecting pipe is connected with the gas purging pipe, the electromagnetic valve is arranged on the opening connecting pipe, and steam is controlled to enter the gas purging pipe through timing opening of the electromagnetic valve; the gas purging pipe is arranged in the container and used for purging the inner wall of the container through steam. The two-section evaporation separator breaks through the traditional thinking, the steam buffer tank, the steam distribution station and the gas purging pipe are arranged, steam purging is adopted, wall bonding or wall growing can be prevented, and the problem that wall bonding and chipping or pipeline blockage easily caused by flushing of a two-section evaporation separator of an existing urea production device is solved. And the problem of shutdown hot washing caused by wall bonding can be effectively avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical production, in particular to the technical field of flushing for preventing crystallization blockage in a urea production device. Background Art

[0002] At present, the second-stage evaporation separator of the evaporation station of the urea production device has the problem of wall formation on the inner wall of the upper head. The wall formation is the imagination that the material in the container crystallizes and becomes thicker on the inner wall. All companies deal with the wall formation by flushing it with steam condensate.

[0003] If the amount of flushing water is too small, the wall cannot be flushed down. If the amount of flushing water is too large, a large amount of water will enter the separator. The water entering the separator absorbs heat and vaporizes, causing the reaction temperature to drop, or a large number of crystal blocks will fall off, blocking the pump or equipment pipe mouth, and the device will be forced to shut down and restart, which will cause fluctuations in product quality and increased energy consumption. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a purging and flushing device which can prevent wall formation or prevent wall formation from growing, and avoid the major disadvantages of using flushing water to flush, which may cause the reaction temperature to drop due to heat absorption caused by water vaporization or the crystal blocks to be too large to block the pipeline.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0006] A flushing device for preventing crystallization blockage comprises: a first regulating valve, a steam buffer tank, a solenoid valve, a gas purge pipe and a steam distribution station;

[0007] The steam buffer tank is provided with a steam inlet pipeline and a steam outlet pipeline;

[0008] The first regulating valve is arranged on the steam inlet pipeline, and the steam is connected to the steam buffer tank by controlling the first regulating valve, and the pressure of the steam buffer tank is controlled and regulated by the first regulating valve;

[0009] The steam distribution station is connected to the steam outlet pipeline, and the steam distribution station is provided with an open pipe, and the open pipe is connected to the gas purge pipe. The solenoid valve is arranged on the open pipe, and the solenoid valve is opened at a fixed time to control the steam to enter the gas purge pipe;

[0010] The gas purge pipe is arranged inside the container and is used for using steam to purge the inner wall of the container.

[0011] As a further technical solution, the gas purge pipe is arranged at the top of the second-stage evaporation separator, so that steam can purge the inner wall of the second-stage evaporation separator through the gas purge pipe.

[0012] As a further technical solution, the gas purge pipe is fixed on the inner wall of the upper head at the top of the two-stage evaporator separator, and the gas purge pipe is provided with three rows of purge holes. The angle between two rows of purge holes in the three rows of purge holes in the gas purge pipe is 60°, and the center line of the middle row of purge holes passes through the center point of the upper head, and the center line of the middle row of purge holes is perpendicular to the gas purge pipe.

[0013] As a further technical solution, the number of the gas purge pipes, open connecting pipes and solenoid valves is more than two; the number of the open connecting pipes and solenoid valves corresponds to the number of gas purge pipes, and one solenoid valve is arranged on one open connecting pipe, which is connected to one gas purge pipe.

[0014] As a further technical solution, the flushing device for preventing crystallization blockage also includes: a second regulating valve and a flow limiting orifice; the second regulating valve regulates the amount of condensate entering the steam buffer tank through the flow limiting orifice.

[0015] As a further technical solution, the flushing device for preventing crystallization blockage also includes: a hydrophobic device, which is arranged at the bottom of the steam buffer tank.

[0016] As a further technical solution, a safety valve, a vent valve and a remote pressure monitoring point are also provided on the top of the steam buffer tank.

[0017] Beneficial effects of the utility model:

[0018] 1. The utility model adopts steam purge by setting a steam buffer tank, a steam distribution station and a gas purge pipe, thereby avoiding the disadvantages of low reaction temperature or too large crystal blocks, which lead to pipeline blockage, caused by the heat absorption of a large amount of water vaporization;

[0019] 2. The utility model is put into use after the production device is started up, which can prevent wall formation or prevent the wall formation from growing, and can effectively avoid the problem of stopping the machine for hot washing due to wall formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic structural diagram of an embodiment of the utility model.

[0021] Figure 2 A schematic diagram of the cross-sectional structure of a gas purge pipe according to an embodiment of the present invention.

[0022] Reference numerals:

[0023] 1. first regulating valve, 2. steam buffer tank, 3. solenoid valve, 4. gas purge pipe, 5. second-stage evaporation separator, 6. steam distribution station, 7. second regulating valve, 8. flow limiting orifice plate, 9. drain device. DETAILED DESCRIPTION

[0024] The utility model is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0025] like Figure 1 As shown, a flushing device for preventing crystallization blockage according to an embodiment of the utility model comprises: a first regulating valve 1 , a steam buffer tank 2 , a solenoid valve 3 , a gas purge pipe 4 and a steam distribution station 6 .

[0026] The steam buffer tank 2 is provided with a steam inlet pipeline and a steam outlet pipeline, and the first regulating valve 1 is arranged on the steam inlet pipeline. The steam is connected to the steam buffer tank 2 by controlling the first regulating valve 1, and the pressure of the steam buffer tank 2 is controlled and regulated by the first regulating valve 1;

[0027] The steam distribution station 6 is connected to the steam outlet pipeline, and is provided with an open pipe, which is connected to the gas purge pipe 4. The solenoid valve 3 is arranged on the open pipe, and the solenoid valve 3 is opened at a fixed time to control the steam to enter the gas purge pipe 4. The gas purge pipe 4 is arranged inside the container and is used to purge the inner wall of the container with steam. The steam in the steam buffer tank 2 can be process steam from the steam network of the urea device, or other steam.

[0028] The gas purge pipe 4 is arranged on the top of the second-stage evaporation separator 5, so that steam can purge the inner wall of the second-stage evaporation separator 5 through the gas purge pipe 4, thereby achieving the purpose of flushing the inner wall of the second-stage evaporation separator 5 to prevent crystallization.

[0029] The gas purge pipe 4 is fixed on the inner wall of the upper head at the top of the second-stage evaporation separator 5. The gas purge pipe 4 is provided with three rows of purge holes, and the hole diameter can be large or small, depending on the actual situation. Steam passes through the three rows of purge holes on the gas purge pipe 4 to purge the crystals; Figure 2 As shown, the angle between two rows of purge holes in the three rows of the gas purge tube 4 is 60°, the center line of the middle row of purge holes passes through the center point of the upper head, and the center line of the middle row of purge holes is perpendicular to the gas purge tube.

[0030] The number of gas purge pipes 4 is more than two, but can be 2, 3, 4, 5, 6, 7, or more, mainly depending on the radius of the top sphere of the second-stage evaporation separator 5. The number of open pipes and solenoid valves 3 is more than two, and the number of open pipes and solenoid valves 3 corresponds to the number of gas purge pipes 4. One solenoid valve 3 is set on one open pipe, and one gas purge pipe 4 is connected.

[0031] In one embodiment, the flushing device for preventing crystallization blockage of the utility model further includes: a second regulating valve 7 and a flow limiting orifice 8; the second regulating valve 7 regulates the amount of condensate to enter the steam buffer tank 2 through the flow limiting orifice 8. The condensate entering the steam buffer tank 2 can be process condensate from a urea device or steam condensate.

[0032] In one embodiment, the flushing device for preventing crystallization blockage of the utility model further includes: a hydrophobic device 9 disposed at the bottom of the steam buffer tank 2 .

[0033] In one embodiment, a safety valve, a vent valve and a remote pressure monitoring point are also provided on the top of the steam buffer tank 2 .

[0034] The specific structures of the above-mentioned drain device, safety valve, vent valve and remote pressure monitoring point are existing technologies and will not be described in detail.

[0035] The operation mode of the utility model is as follows:

[0036] The process steam enters the steam buffer tank 2 through the first regulating valve 1, and the pressure of the steam buffer tank 2 is also controlled and regulated by the first regulating valve 1. The second regulating valve 7 is used to regulate the amount of process condensate entering the steam buffer tank through the flow limiting orifice plate. There is a drain device at the bottom of the steam buffer tank 2, and a safety valve, a vent valve and a remote pressure monitoring point are arranged on the top of the steam buffer tank 2. After the steam leaves the buffer tank, it enters the steam distribution station 6, and is opened regularly by the solenoid valve 3 to enter the gas purge pipe 4 at the top of the second-stage evaporation separator 5. The steam purges the crystals through the 3 rows of purge holes on the gas purge pipe, so as to achieve the purpose of preventing crystallization on the internal wall of the second-stage evaporation separator 5.

[0037] The advantages of the utility model are:

[0038] 1. The utility model adopts steam purging to avoid the disadvantages of low reaction temperature or too large crystal blocks, which lead to pipeline blockage, caused by the absorption of heat by a large amount of water vaporization;

[0039] 2. Most companies use hot washing equipment to remove the wall buildup in the second stage evaporation separator after it has been running for a period of time. The utility model is put into use right after the production unit is started up, which can prevent wall buildup or prevent the wall buildup from growing, and can effectively avoid the problem of stopping the plant for hot washing due to wall buildup.

[0040] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A flushing device for preventing crystallization blockage, characterized in that: It includes: The first regulating valve, steam buffer tank, solenoid valve, gas purge pipe and steam distribution station; The steam buffer tank is provided with a steam inlet pipeline and a steam outlet pipeline; The first regulating valve is arranged on the steam inlet pipeline, and the steam is connected to the steam buffer tank by controlling the first regulating valve, and the pressure of the steam buffer tank is controlled and regulated by the first regulating valve; The steam distribution station is connected to the steam outlet pipeline, and the steam distribution station is provided with an open pipe, and the open pipe is connected to the gas purge pipe. The solenoid valve is arranged on the open pipe, and the solenoid valve is opened at a fixed time to control the steam to enter the gas purge pipe; The gas purge pipe is arranged inside the container and is used for using steam to purge the inner wall of the container.

2. A flushing device for preventing crystallization blockage according to claim 1, characterized in that: The gas purge pipe is arranged on the top of the second-stage evaporation separator, so that steam can purge the inner wall of the second-stage evaporation separator through the gas purge pipe.

3. A flushing device for preventing crystallization blockage according to claim 2, characterized in that: The gas purge pipe is fixed on the inner wall of the upper head at the top of the two-stage evaporator separator. The gas purge pipe is provided with three rows of purge holes. The angle between two rows of purge holes in the three rows of purge holes in the gas purge pipe is 60°. The center line of the middle row of purge holes passes through the center point of the upper head, and the center line of the middle row of purge holes is perpendicular to the gas purge pipe.

4. A flushing device for preventing crystallization blockage according to claim 1, 2 or 3, characterized in that: The number of the gas purge pipe, the open pipe and the solenoid valve is more than two; The number of the open pipes and the electromagnetic valves corresponds to the number of the gas purge pipes. One electromagnetic valve is arranged on one open pipe and connected to one gas purge pipe.

5. A flushing device for preventing crystallization blockage according to claim 1, 2 or 3, characterized in that: It also includes: a second regulating valve and a flow limiting orifice; The second regulating valve regulates the amount of condensate entering the steam buffer tank through the flow limiting orifice plate.

6. A flushing device for preventing crystallization blockage according to claim 5, characterized in that: It also includes: a drain device, which is arranged at the bottom of the steam buffer tank.

7. A flushing device for preventing crystallization blockage according to claim 6, characterized in that: A safety valve, a vent valve and a remote pressure monitoring point are also provided on the top of the steam buffer tank.

Images