flasher feed pump outlet melt line to final polymerizer nitrogen protection device

Abstract

The utility model discloses nitrogen protection device from flash evaporator feeding pump outlet melt pipeline to final polymerization kettle, including heating case, the left side of heating case is provided with exhaust port and gas delivery port, the side fixed mounting of gas delivery port away from heating case has first electric control valve, the side fixed mounting of exhaust port away from heating case has drain valve, the inside fixed mounting of heating case has heat exchange pipe, one end of heat exchange pipe is fixedly connected with gas delivery pipe, the fixed mounting of gas delivery pipe away from one end of heat exchange pipe has two third electric control valves. The utility model utilizes the inactivity gas after heating to enter final polymerization kettle, improves final polymerization kettle pressure, keeps melt pipeline and final polymerization kettle pressure above positive pressure, and is very stable, and the inactivity gas after heating also can not cause the condensation of melt, and air can not enter melt pipeline, until the maintenance of flash evaporator feeding pump is finished, restores the connection. After putting into use, can effectively avoid the air into melt pipeline, and the melt is not oxidized and black.

Description

Technical Field

[0001] This utility model relates to the field of feed pump maintenance technology, specifically to a nitrogen protection device for the melt pipeline from the flash evaporator feed pump outlet to the final polymerization reactor. Background Technology

[0002] When the flash evaporator feed pump (gear pump) is under maintenance, air can easily enter the outlet melt pipe, causing the melt inside the pipe to oxidize and turn black. The current process in the market is to add emergency steam to the final polymerization reactor to break the vacuum and maintain the equipment pressure above positive pressure. However, steam is very prone to phase change and liquefaction due to temperature changes, resulting in a sharp volume contraction and allowing air to enter the equipment. This makes the process very unstable, and the oxidized black material will cause the product to be substandard and downgraded. It generally takes more than 3 days to completely replace the oxidized material. The price of the downgraded product is about 3,000 yuan per ton lower than that of the qualified product, which seriously affects the product profit. Therefore, we propose a nitrogen protection device from the outlet melt pipe of the flash evaporator feed pump to the final polymerization reactor. Utility Model Content

[0003] The purpose of this utility model is to provide a nitrogen protection device for the melt pipeline from the flash evaporator feed pump outlet to the final polymerization kettle, in order to solve the problem mentioned in the background art that the existing process in the market is to add emergency steam to the final polymerization kettle to break the vacuum and keep the equipment pressure above positive pressure. However, the steam is very easy to undergo phase change and liquefaction due to temperature changes, and its volume shrinks drastically, causing air to enter the equipment, which is very unstable. Moreover, the oxidized black material will lead to the product being unqualified and downgraded.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a nitrogen protection device from the melt pipeline at the flash evaporator feed pump outlet to the final polymerization reactor, comprising: A heating chamber has an exhaust port and a steam inlet on its left side. A first electrically controlled valve is fixedly installed on the side of the steam inlet away from the heating chamber, and a drain valve is fixedly installed on the side of the exhaust port away from the heating chamber. A heat exchange tube is fixedly installed inside the heating chamber, and a gas supply pipe is fixedly connected to one end of each heat exchange tube. Two third electrically controlled valves are fixedly installed on the end of the gas supply pipe away from the heat exchange tube. The output ends of the third electrically controlled valves are fixedly connected to a final polymerization reactor. The input to the final polymerization reactor... A second electrically controlled valve is installed at one end of the heat exchange tube. The input end of the second electrically controlled valve is fixedly connected to a flash evaporator. The input end of the flash evaporator is fixedly connected to a feed pump. The other end of the heat exchange tube is fixedly connected to a fourth electrically controlled valve.

[0005] As a preferred embodiment of the nitrogen protection device from the outlet melt pipeline of the flash evaporator feed pump to the final polymerization reactor of this utility model, the heat exchange tube runs through the interior of the heating box and the heat exchange tube has an S-shaped structure.

[0006] In a preferred embodiment of the nitrogen protection device from the outlet melt pipeline of the flash evaporator feed pump to the final polymerization reactor, the heat exchange tube is connected to the final polymerization reactor via the third electrically controlled valve and the gas supply pipe, the final polymerization reactor is connected to the flash evaporator via the second electrically controlled valve, and the flash evaporator is connected to the output end of the feed pump.

[0007] In a preferred embodiment of the nitrogen protection device for the flash evaporator feed pump outlet melt pipeline to the final polymerization reactor of this utility model, the first electrically controlled valve is connected to the heating box through the steam inlet, and the heating box is connected to the drain valve through the steam outlet.

[0008] In a preferred embodiment of the flash evaporator feed pump outlet melt pipeline to the final polymerization reactor nitrogen protection device of this utility model, the heat exchange tube is connected to the fourth electrically controlled valve.

[0009] As a preferred embodiment of the nitrogen protection device for the flash evaporator feed pump outlet melt pipeline to the final polymerization reactor of this utility model, the heating box is further provided with: An insulation layer is fixedly installed on the inner wall of the heating box.

[0010] Compared with the prior art, this utility model provides a nitrogen protection device from the melt pipeline at the outlet of the flash evaporator feed pump to the final polymerization reactor, which has the following advantages: This invention utilizes heated inert gas introduced into the final polymerization reactor to increase the reactor pressure, maintaining a stable positive pressure above the normal pressure in the melt pipeline and the final polymerization reactor. The heated inert gas does not cause condensation of the molten material, and air cannot enter the melt pipeline until the flash evaporator feed pump is repaired and reconnected. After being put into operation, this effectively prevents air from entering the melt pipeline, preventing the melt from oxidizing and turning black, and allowing for faster product quality compliance—generally within an hour—effectively increasing product profits. Attached Figure Description

[0011] Figure 1 is a schematic diagram of the overall structure of this utility model; Figure 2 is a schematic diagram of the internal structure of the heating box of this utility model.

[0012] In the diagram: 1. Heating box; 2. Exhaust port; 3. Drain valve; 4. First solenoid valve; 5. Feed pump; 6. Flash evaporator; 7. Second solenoid valve; 8. Final polymerization reactor; 9. Third solenoid valve; 10. Gas supply pipe; 11. Fourth solenoid valve; 12. Steam outlet; 13. Heat exchange tube; 14. Insulation layer. Detailed Implementation

[0013] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0014] Please refer to Figure 1 and Figure 2 The flash evaporator feed pump outlet melt pipeline to the final polymerization kettle nitrogen protection device includes a heating box 1. A steam exhaust port 2 and a steam inlet 12 are provided on the left side of the heating box 1. A first electrically controlled valve 4 is fixedly installed on the side of the steam inlet 12 away from the heating box 1. A drain valve 3 is fixedly installed on the side of the steam exhaust port 2 away from the heating box 1. A heat exchange tube 13 is fixedly installed inside the heating box 1. One end of the heat exchange tube 13 is fixedly connected to a gas supply pipe 10. Two third electrically controlled valves 9 are fixedly installed on the end of the gas supply pipe 10 away from the heat exchange tube 13. The output end of the third electrically controlled valve 9 is fixedly connected to the final polymerization kettle 8. A second electrically controlled valve 7 is installed at the input end of the final polymerization kettle 8. The input end of the second electrically controlled valve 7 is fixedly connected to a flash evaporator 6. The input end of the flash evaporator 6 is fixedly connected to a feed pump 5. The other end of the heat exchange tube 13 is fixedly connected to a fourth electrically controlled valve 11.

[0015] In this embodiment: the present invention utilizes heated inert gas to enter the final polymerization reactor 8, and the final polymerization reactor... 8. Increase the pressure to maintain a stable, positive pressure above the standard pressure in the melt pipeline and final polymerization reactor. The inert gas after heating will not cause the melt to condense, and air cannot enter the melt pipeline until the flash evaporator 6 and feed pump 5 are repaired and reconnected. After commissioning, this effectively prevents air from entering the melt pipeline, prevents the melt from oxidizing and turning black, and allows for faster product quality compliance, typically within about 3 hours, effectively increasing product profits.

[0016] Furthermore: In an optional embodiment, the heat exchange tube 13 extends through the interior of the heating box 1 and has an S-shaped structure.

[0017] In this implementation scheme, the contact area between the heat exchange tube 13 and the steam is increased by the above-mentioned technology, thereby improving the heating efficiency of nitrogen.

[0018] Furthermore: In an optional embodiment, the heat exchange tube 13 is connected to the final polymerization reactor 8 via the third solenoid valve 9 and the gas supply pipe 10. The final polymerization reactor 8 is connected to the flash evaporator 6 via the second solenoid valve 7. The flash evaporator 6 is connected to the output end of the feed pump 5.

[0019] In this implementation scheme, the heated nitrogen gas is delivered to the connecting pipe between the flash evaporator 6 and the feed pump 5 using the above-mentioned technology.

[0020] Furthermore: In an optional embodiment, the first electrically controlled valve 4 is connected to the heating box 1 through the steam inlet 12, and the heating box 1 is connected to the drain valve 3 through the steam outlet 2.

[0021] In this implementation scheme, the above-mentioned technology is used to deliver steam into the interior of the heating box 1 for nitrogen heating.

[0022] Furthermore: In an optional embodiment, the heat exchange tube 13 is connected to the fourth electrically controlled valve 11.

[0023] In this embodiment, the above-mentioned technology is used to deliver nitrogen gas into the interior of the heat exchange tube 13 for heating.

[0024] Furthermore: In an optional embodiment, the heating chamber 1 further includes: The insulation layer 14 is fixedly installed on the inner wall of the heating box 1.

[0025] In this implementation scheme, the insulation layer 14 enhances the insulation performance of the heating box 1 and reduces heat loss.

[0026] Working Principle: When using the flash evaporator feed pump outlet melt pipeline to the final polymerization kettle nitrogen protection device, firstly, the first solenoid valve 4 and the drain valve 3 are opened to allow steam to enter the interior of the heating box 1 through the steam distribution station and steam outlet 12. The insulation layer 14 enhances the insulation performance of the heating box 1 and reduces heat loss. Secondly, the fourth solenoid valve 11 is opened, and the nitrogen inside the low-pressure nitrogen common pipeline enters the interior of the heat exchange tube 13 to exchange heat with the steam, thus achieving nitrogen heating. Excess steam and liquefied water flow into the process trench for discharge through the exhaust port 2 and the drain valve 3. At the same time, the third solenoid valve 9 and the second solenoid valve 7 are opened, and the nitrogen heated inside the heat exchange tube 13 enters the interior of the final polymerization kettle 8 through the gas pipeline 10 and the third solenoid valve 9, then enters the interior of the flash evaporator 6 through the second solenoid valve 7, and then exits from the pipeline connecting the flash evaporator 6 and the feed pump 5, so that the final polymerization kettle 8 and the flash evaporator 6 are heated. Maintain positive pressure in the melt pipeline at the outlet of feed pump 5. Then, feed pump 5 can be disassembled for maintenance until maintenance is completed and the connection is restored. During maintenance, air can be effectively prevented from entering the melt pipeline, thus preventing the melt inside the pipeline from being oxidized and turning black. Flash evaporator 6 and final polymerization reactor 8 are existing technologies and will not be described in detail here. This is the working principle of the nitrogen protection device from the melt pipeline at the outlet of the flash evaporator feed pump to the final polymerization reactor.

[0027] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A nitrogen protection device from the melt pipeline at the outlet of the flash evaporator feed pump to the final polymerization reactor, characterized in that, include: A heating box (1) is provided with a steam vent (2) and a steam inlet (12) on the left side. A first electric control valve (4) is fixedly installed on the side of the steam inlet (12) away from the heating box (1). A drain valve (3) is fixedly installed on the side of the steam vent (2) away from the heating box (1). A heat exchange tube (13) is fixedly installed inside the heating box (1). A gas supply pipe (10) is fixedly connected to one end of the heat exchange tube (13). Two third electric control valves (9) are fixedly installed at the end of the gas supply pipe (10) away from the heat exchange tube (13). A final polymerization reactor (8) is fixedly connected to the output end of the third electric control valve (9). A second electric control valve (7) is installed at the input end of the final polymerization reactor (8). A flash evaporator (6) is fixedly connected to the input end of the second electric control valve (7). A feed pump (5) is fixedly connected to the input end of the flash evaporator (6). A fourth electric control valve (11) is fixedly connected to the other end of the heat exchange tube (13).

2. The nitrogen protection device from the flash evaporator feed pump outlet melt pipeline to the final polymerization reactor according to claim 1, characterized in that, The heat exchange tube (13) runs through the interior of the heating box (1), and the heat exchange tube (13) has an S-shaped structure.

3. The nitrogen protection device from the flash evaporator feed pump outlet melt pipeline to the final polymerization reactor according to claim 1, characterized in that, The heat exchange tube (13) is connected to the final polymerization reactor (8) through the third electric control valve (9) and the gas supply pipe (10). The final polymerization reactor (8) is connected to the flash evaporator (6) through the second electric control valve (7). The flash evaporator (6) is connected to the output end of the feed pump (5).

4. The nitrogen protection device from the flash evaporator feed pump outlet melt pipeline to the final polymerization reactor according to claim 1, characterized in that, The first electrically controlled valve (4) is connected to the heating box (1) through the steam outlet (12), and the heating box (1) is connected to the drain valve (3) through the steam outlet (2).

5. The nitrogen protection device from the flash evaporator feed pump outlet melt pipeline to the final polymerization reactor according to claim 1, characterized in that, The heat exchange tube (13) is connected to the fourth electrically controlled valve (11).

Images