Long-period operation equipment for EO refining tower of ethylene oxide device

Abstract

The utility model discloses long-period operation equipment for an ethylene oxide device EO (Ethylene Oxide) refining tower, which belongs to the technical field of chemical production and comprises an EO refining tower, an aftercooler at the top of the EO refining tower is connected with an EO refining tower return tank through a pipeline, the EO refining tower return tank is provided with a pipeline, and branches of the pipeline are respectively provided with a pressure control valve a and a pressure control valve b. The bottom of the EO refining tower return tank is connected with the EO refining tower through a pipeline, an online analyzer, a gate valve e and an EO refining tower return tank kettle pump are arranged on the pipeline, a branch pipeline is arranged on the pipeline at the bottom of the EO refining tower return tank, and a gate valve d, an EO refining tower return impurity removal tank, an EO refining tower return impurity removal delivery pump, a flowmeter c and a flow control valve c are arranged on the branch pipeline; according to the utility model, the high-load vapor-state ethylene oxide discharged from the tower top of the EO refining tower is recovered, and meanwhile, the reflux ethylene oxide part with excessive impurities is removed, so that the situation that the recovered ethylene oxide in high-load operation has large quality fluctuation and is unstable is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical production, in particular to long-cycle operation equipment for an EO refining tower of an ethylene oxide device. Background Art

[0002] EO machine ethylene oxide, in the ethylene oxide plant, the EO refining tower is a long-cycle ethylene oxide production equipment used to ensure the stable operation of the EO refining tower and ensure that the EO refining tower can continuously and stably produce qualified products under high load for a long time. The long-term operation of the EO refining tower can maximize the balance of the energy consumption of the plant, increase the annual output of EO products, and reduce the unit consumption and material loss of the plant. Therefore, the longer the EO refining tower operates at a continuous high load, the better the economic benefits of the ethylene oxide plant.

[0003] In the prior art, the ethylene oxide produced in the EO refining tower needs to be cooled before being transported to the EO spherical tank. A portion of the ethylene oxide is discharged through the top of the EO refining tower when the internal pressure is too high. This discharged portion of ethylene oxide results in waste of ethylene oxide. Therefore, the prior art requires the recovery of the discharged ethylene oxide. However, the prior art results in excessive impurities in the product when the EO refining tower of the ethylene oxide plant is operated at high load. Long-term operation of the EO refining tower also leads to accumulation of impurities in the product, resulting in large fluctuations and instability in the quality of the recovered ethylene oxide during high-load operation. Utility Model Content

[0004] In order to solve the technical problems mentioned in the above background technology, the utility model provides an EO refining tower long-cycle operation device for an ethylene oxide device, and the technical solution adopted is as follows:

[0005] The EO refining tower comprises an EO refining tower, a thermometer b is provided on the EO refining tower, an EO refining tower tray is provided in the EO refining tower, a pressure gauge a and a thermometer a are provided on the top of the EO refining tower, the upper part of the EO refining tower is connected to the EO refining tower top condenser through a pipeline, the EO refining tower is connected to the EO refining tower top aftercooler through a pipeline, the EO refining tower top aftercooler is connected to the EO refining tower reflux tank through a pipeline, a pressure gauge b is provided on the EO refining tower reflux tank, and the EO refining tower A pipeline is provided on the reflux tank, and pressure control valves a and pressure control valve b are respectively provided on the branches of the pipeline. The bottom of the EO refining tower reflux tank is connected to the EO refining tower through a pipeline, and an online analyzer, a gate valve e and an EO refining tower reflux tank kettle pump are provided on the pipeline. A branch pipeline is provided on the bottom pipeline of the EO refining tower reflux tank, and a gate valve d, an EO refining tower reflux impurity removal tank, an EO refining tower reflux impurity removal external pump, a flow meter c and a flow control valve c are provided on the branch pipeline.

[0006] Furthermore, a parallel pipeline is provided on the left side of the EO refining tower and gate valves b and c are provided on the parallel pipelines respectively.

[0007] Furthermore, a parallel pipeline is provided on the left side of the EO refining tower, and a flow meter b, a flow control valve a, a gate valve f and a gate valve a are respectively provided on the parallel pipeline.

[0008] Furthermore, one side of the EO refining tower is connected to an EO refining tower product cooler through a pipeline, the EO refining tower product cooler is connected to an EO refining tower kettle pump through a pipeline, the EO refining tower kettle pump is connected to an EO refining tower product aftercooler through a pipeline, and an EO online analyzer is provided on the pipeline.

[0009] Furthermore, one side of the EO refining tower is connected to an EO refining tower reboiler through a pipeline, a route is connected in parallel to the EO refining tower reboiler and a flow meter a and a flow control valve b are provided on the route, and the bottom of the EO refining tower reboiler is connected to the bottom of the EO refining tower through a pipeline.

[0010] Furthermore, the bottom of the EO refining tower is connected to an EO refining tower kettle delivery pump through a pipeline.

[0011] The utility model has the following advantages: the vaporous ethylene oxide discharged from the top of the EO refining tower at high load is pre-cooled by the condenser at the top of the EO refining tower, and then further cooled and condensed into liquid by the aftercooler at the top of the EO refining tower, and then enters the reflux tank of the EO refining tower for storage, and nitrogen is introduced into the reflux tank of the EO refining tower and discharged, so that the reflux flow rate of the refluxed ethylene oxide in the reflux tank of the EO refining tower is stabilized under the pressure-maintaining state, and then the reflux tank is pumped back to the EO refining tower through the kettle of the EO refining tower. When the online analyzer analyzes the ethylene oxide concentration in the reflux line, the reflux line is filled with nitrogen and discharged, and the reflux line is filled with nitrogen and discharged, so that the reflux flow rate of the refluxed ethylene oxide in the reflux tank of the EO refining tower is stabilized, and the reflux line is pumped back to the EO refining tower through the kettle of the reflux tank of the EO refining tower. When the set value is exceeded, it indicates that the impurity content in the refluxed ethylene oxide is too high. The reflux route is closed and the route to the EO refining tower reflux impurity removal tank is opened, so that the refluxed ethylene oxide enters the EO refining tower reflux impurity removal tank and is pumped to the EG section, i.e., the ethylene glycol production section, through the EO refining tower reflux impurity removal external pump. The utility model recovers the vaporous ethylene oxide discharged from the top of the EO refining tower at high load while removing the refluxed ethylene oxide portion with excessive impurities, thereby avoiding large fluctuations and instability in the quality of the recovered ethylene oxide during high-load operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the utility model process.

[0013] Figures: 1-flow control valve a, 2-flow meter a, 3-flow control valve b, 4-flow meter b, 5-EO refining tower reboiler, 6-EO refining tower, 7-EO refining tower tray, 8-EO online analyzer, 9-pressure gauge a, 10-thermometer a, 11-EO refining tower product cooler, 12-EO refining tower kettle delivery pump, 13-EO refining tower kettle pump, 14-flow meter c, 15-flow control valve c, 16-EO refining tower reflux tank kettle pump, 17- EO refining tower reflux tank, 18-pressure control valve a, 19-pressure control valve b, 20-pressure gauge b, 21-EO refining tower top aftercooler, 22-EO refining tower product aftercooler, 23-gate valve a, 24 thermometer b, 25-gate valve f, 26-gate valve b, 27-gate valve c, 28-EO refining tower top condenser, 29-EO refining tower reflux impurity removal tank, 30-online analyzer, 31-EO refining tower reflux impurity removal external pump, 32-gate valve d, 33-gate valve e. DETAILED DESCRIPTION

[0014] 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 embodiments described 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 making creative efforts are within the scope of protection of the present invention.

[0015] Please refer to Figure 1The utility model discloses an EO refining tower long-cycle operation device for an ethylene oxide device, comprising an EO refining tower 6 for producing ethylene oxide. A thermometer b24 is provided on the EO refining tower 6 for monitoring the temperature at the bottom of the EO refining tower 6. An EO refining tower tray 7 is provided in the EO refining tower 6 for providing a place for gas-liquid contact in the EO refining tower 6. A pressure gauge a9 and a thermometer a10 are provided on the top of the EO refining tower for monitoring the pressure and temperature at the top of the EO refining tower 6. The upper part of the EO refining tower 6 is connected to an EO refining tower top condenser 28 through a pipeline. The EO refining tower 6 is at a high temperature. The ethylene oxide discharged under load first enters the EO refining tower top condenser 28 through a pipeline for pre-cooling, and then enters the EO refining tower top aftercooler 21 through a pipeline for aftercooling, so that the vaporous epoxy resin is cooled into a liquid state. The EO refining tower 6 is connected to the EO refining tower top aftercooler 21 through a pipeline, and the EO refining tower top aftercooler 21 is connected to the EO refining tower reflux tank 17 through a pipeline. The liquid epoxy resin enters the EO refining tower reflux tank 17 through a pipeline for buffering. The EO refining tower reflux tank 17 is provided with a pressure gauge b20. The EO refining tower reflux tank 17 is provided with a pipeline and The branch lines of the pipeline are respectively provided with pressure control valves a18 and b19. Nitrogen enters the EO refining tower reflux tank 17 through the branch line on the pressure control valve b19 and then comes out through the branch line on the pressure control valve a18 to ensure the pressure balance in the EO refining tower reflux tank 17 and to stabilize the flow rate and velocity of the refluxed ethylene oxide. The pressure control valves b19 and a18 each control the switch of the corresponding branch line. The pressure in the EO refining tower reflux tank 17 is monitored by a pressure gauge b20. The bottom of the EO refining tower reflux tank 17 is connected to the EO refining tower 6 through a pipeline. The pipeline is also equipped with an online analyzer 30, a gate valve e33 and an EO refining tower reflux tank bottom pump 16. The refluxed ethylene oxide will be deposited in the EO refining tower reflux tank 17. When it refluxes to the EO refining tower 6 through the pipeline, the online analyzer 30 monitors the ethylene oxide concentration in the reflux pipeline to analyze the impurity content in the ethylene oxide. A branch pipeline is provided on the bottom pipeline of the EO refining tower reflux tank 17, and the branch pipeline is equipped with a gate valve d32, an EO refining tower reflux impurity removal tank 29, an EO refining tower reflux impurity removal external pump 31, a flow meter c14 and a flow control valve c15.

[0016] A parallel pipeline is provided on the left side of EO refining tower 6, and gate valves b26 and c27 are respectively installed on the parallel pipeline. Demineralized water, one of the raw materials for ethylene oxide production, enters EO refining tower 6 through this parallel pipeline. The parallel pipeline is equipped with gate valves b26 and c27. When one gate valve is open, the other gate valve is closed. When a problem occurs in one gate valve, the other gate valve can be opened. DMW refers to demineralized water.

[0017] A parallel pipeline is provided on the left side of the EO refining tower 6. A flow meter b4, flow control valve a1, gate valve f25, and gate valve a23 are installed on this parallel pipeline. The dehydrogenated component in the dehydrogenation component tower, which serves as one of the raw materials for producing ethylene oxide, enters the EO refining tower 6 through this parallel pipeline. This parallel pipeline is equipped with gate valve f25 and gate valve a23. When one gate valve is open, the other is closed. If a problem occurs with one gate valve, the other gate valve can be opened. The flow rate of the dehydrogenated component in this parallel pipeline is controlled by the flow meter b4 and flow control valve a1.

[0018] One side of the EO refining tower 6 is connected to an EO refining tower product cooler 11 via a pipeline. The finished ethylene oxide produced by the EO refining tower 6 enters the EO refining tower product cooler 11 through the pipeline for pre-cooling. The EO refining tower product cooler 11 is connected to an EO refining tower kettle pump 13 via a pipeline. The ethylene oxide pre-cooled in the EO refining tower product cooler 11 is sent to the EO refining tower product aftercooler 22 via the EO refining tower kettle pump 13 for post-cooling. The EO refining tower kettle pump 13 is connected to the EO refining tower product aftercooler 22 via a pipeline, and an EO online analyzer 8 is provided on the pipeline. The EO online analyzer 8 is used to analyze the concentration of ethylene oxide in the pipeline to determine the quality of the ethylene oxide. The ethylene oxide after cooling in the EO refining tower product aftercooler 22 is sent to the EO spherical tank.

[0019] One side of the EO refining tower 6 is connected to the EO refining tower reboiler 5 via a pipeline. A route is connected in parallel to the EO refining tower reboiler 5 and is equipped with a flow meter a2 and a flow control valve b3. The bottom of the EO refining tower reboiler 5 is connected to the bottom of the EO refining tower 6 via a pipeline. An overflow plate is provided at the bottom of the EO refining tower 6, and an inclined plate is provided above the overflow plate. Waste liquid in the EO refining tower 6 falls onto the inclined plate and flows through the inclined plate to the space to the right of the overflow plate. Impurities in the waste liquid are precipitated in the space to the right of the overflow plate, while the clean ethylene oxide solution in the waste liquid flows over the left side of the overflow plate and enters the space to the left of the overflow plate. It then enters the EO refining tower reboiler 5 through a pipeline for reboiled heating and is then sent back to the EO refining tower 6 to produce more ethylene oxide. The ethylene oxide flow in the pipeline is controlled by the flow meter a2 and the flow control valve b3.

[0020] The bottom of the EO refining tower 6 is connected to an EO refining tower kettle delivery pump 12 through a pipeline. The impurities precipitated in the space on the right side of the overflow plate in the EO refining tower 6 are transported to the EG section through the EO refining tower kettle delivery pump 12, where EG is the ethylene glycol section.

[0021] The working principle of the present invention is as follows: the vaporous ethylene oxide discharged from the top of the EO refining tower 6 at high load enters the EO refining tower top condenser 28 through a pipeline, is pre-cooled by the EO refining tower top condenser 28, then enters the EO refining tower top aftercooler 21 through a pipeline, is further cooled and condensed into liquid by the EO refining tower top aftercooler 21, and then enters the EO refining tower reflux tank 17 through a pipeline for storage. The impurities in the ethylene oxide are partially precipitated in the EO refining tower reflux tank 17. The pressure control valve a18 and the pressure control valve b19 are opened, and nitrogen is introduced into the EO refining tower reflux tank 17 and discharged, so that the reflux flow rate of the refluxed ethylene oxide in the EO refining tower reflux tank 17 is stabilized under the pressure-maintaining state. The gate valve e3 is opened. 3. Close gate valve d32. Then, the ethylene oxide in the EO refining tower reflux tank 17 is returned to the EO refining tower 6 via the pipeline through the EO refining tower reflux tank bottom pump 16. When the online analyzer 30 indicates that the ethylene oxide concentration in the reflux pipeline exceeds the set value, it means that the impurity content in the refluxed ethylene oxide is too high. The reflux route is closed, that is, the gate valve e33 is closed, and the route to the EO refining tower reflux impurity removal tank 29 is opened, that is, the gate valve d32 is opened, so that the ethylene oxide in the EO refining tower reflux tank 17 enters the EO refining tower reflux impurity removal tank 29 and is sent to the EG section, that is, the ethylene glycol production section, by the EO refining tower reflux impurity removal external pump 31. The pipeline discharge flow is controlled by the flow meter c14 and the flow control valve c15.

[0022] The present invention is simple to operate and easy to use, and is suitable for comprehensive promotion and application. Although the 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 variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An EO refining tower long-cycle operation device for an ethylene oxide device, comprising an EO refining tower (6), a thermometer b (24) being provided on the EO refining tower (6), and an EO refining tower tray (7) being provided in the EO refining tower (6), characterized in that: The top of the EO refining tower is provided with a pressure gauge a (9) and a thermometer a (10), the upper part of the EO refining tower (6) is connected to the EO refining tower top condenser (28) through a pipeline, the EO refining tower (6) is connected to the EO refining tower top aftercooler (21) through a pipeline, the EO refining tower top aftercooler (21) is connected to the EO refining tower reflux tank (17) through a pipeline, the EO refining tower reflux tank (17) is provided with a pressure gauge b (20), the EO refining tower reflux tank (17) is provided with a pipeline and the branch lines of the pipeline are respectively provided with pressure control A control valve a (18) and a pressure control valve b (19) are provided. The bottom of the EO refining tower reflux tank (17) is connected to the EO refining tower (6) through a pipeline, and an online analyzer (30), a gate valve e (33) and an EO refining tower reflux tank kettle pump (16) are provided on the pipeline. A branch pipeline is provided on the bottom pipeline of the EO refining tower reflux tank (17), and a gate valve d (32), an EO refining tower reflux impurity removal tank (29), an EO refining tower reflux impurity removal external pump (31), a flow meter c (14) and a flow control valve c (15) are provided on the branch pipeline.

2. The long-cycle operation equipment for the EO refining tower of an ethylene oxide device according to claim 1, characterized in that: A parallel pipeline is provided on the left side of the EO refining tower (6), and a gate valve b (26) and a gate valve c (27) are respectively provided on the parallel pipeline.

3. The long-cycle operation equipment for the EO refining tower of an ethylene oxide device according to claim 2, characterized in that: A parallel pipeline is provided on the left side of the EO refining tower (6), and a flow meter b (4), a flow control valve a (1), a gate valve f (25) and a gate valve a (23) are respectively provided on the parallel pipeline.

4. The long-cycle operation equipment for the EO refining tower of an ethylene oxide device according to claim 1, characterized in that: One side of the EO refining tower (6) is connected to an EO refining tower product cooler (11) via a pipeline, the EO refining tower product cooler (11) is connected to an EO refining tower kettle pump (13) via a pipeline, the EO refining tower kettle pump (13) is connected to an EO refining tower product aftercooler (22) via a pipeline, and an EO online analyzer (8) is provided on the pipeline.

5. The long-cycle operation equipment for the EO refining tower of an ethylene oxide device according to claim 1, characterized in that: One side of the EO refining tower (6) is connected to the EO refining tower reboiler (5) via a pipeline. A route is connected in parallel to the EO refining tower reboiler (5) and a flow meter a (2) and a flow control valve b (3) are provided on the route. The bottom of the EO refining tower reboiler (5) is connected to the bottom of the EO refining tower (6) via a pipeline.

6. The long-cycle operation equipment for the EO refining tower of an ethylene oxide device according to claim 1, characterized in that: The bottom of the EO refining tower (6) is connected to an EO refining tower kettle delivery pump (12) via a pipeline.

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