Chemical process condensate recycling device

Abstract

The utility model relates to the technical field of chemical engineering, in particular to a process condensate recycling device for chemical engineering, which is characterized in that the bottom of a medium-temperature gas separator I, the bottom of a medium-temperature gas separator II and the bottom of a medium-temperature gas separator III are respectively connected with a process condensate recycling pipeline I, and the three process condensate recycling pipelines I are jointly connected with a recycling collecting pipe; and one end, far away from the three process condensate recovery pipelines I, of the recovery collecting pipe is connected to the inlet end of the process condensate stripping tower. According to the utility model, stripping steam is fed into the process condensate stripping tower through the stripping steam pipelines, so that acid gas is removed, and the PH value of the process condensate is reduced; the process condensate is pressurized by the process condensate pump and then enters the deaerator through the process condensate recovery pipeline II to prepare boiler feed water, so that the use amount of demineralized water is reduced, and meanwhile, the hydrogen production cost is reduced; the utility model solves the problems in the prior art that when the process condensate is discharged, the energy is wasted, the noise is larger, and the discharged process condensate severely pollutes the surrounding equipment and facilities.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical industry, in particular to a recycling device for process condensate used in chemical industry. Background Art

[0002] Most of the existing hydrogen production devices use hydrocarbon steam reforming process to produce hydrogen, but the hydrogen production raw materials are mostly single media, which can generally be divided into two categories: gaseous hydrocarbons and liquid hydrocarbons. Gaseous hydrocarbons mainly include natural gas, oilfield gas, biogas, hydrogenated dry gas, reformed dry gas, catalytic dry gas and aromatization dry gas; liquid hydrocarbons mainly include straight-run naphtha, hydrogenated light naphtha, raffinate and topped oil produced by reforming units, and saturated liquefied petroleum gas produced by hydrogenation units.

[0003] The prior art also has a multi-component steam reforming process for hydrogen production, which generally uses a mixed gas composed of coke oven gas, low-temperature dry distillation gas and natural gas in different proportions as a hydrogen production raw material.

[0004] In the existing technology, in the process of converting multi-component raw materials into hydrogen, there is a phenomenon that the continuous process condensate cannot be recycled and can only be discharged into the sewage treatment plant for treatment. The high-pressure process condensate system not only wastes energy and makes a lot of noise when discharging the process condensate, but also the discharged process condensate causes serious damage to the surrounding equipment and facilities. Utility Model Content

[0005] The utility model aims to provide a device for recycling process condensate for chemical industry, so as to solve the problem that process condensate cannot be recycled and directly discharged in the process of hydrogen production by conversion in the prior art.

[0006] In order to solve the above technical problems, the utility model discloses a process condensate recycling device for chemical industry, which comprises a medium-change gas input pipeline, a process condensate collecting unit, and a process condensate stripping tower. The process condensate collecting unit comprises a medium-change gas separator I, a medium-change gas separator II and a medium-change gas separator III. The medium-change gas separator I, the medium-change gas separator II and the medium-change gas separator III are connected in series. The medium-change gas input pipeline is connected to the inlet end of the medium-change gas separator I. The top of the medium-change gas separator I is connected to an intermediate conveying pipeline. The end of the intermediate conveying pipeline away from the medium-change gas separator I is connected to the medium-change gas separator. The inlet end of the medium-shift gas separator II is connected to the top of the medium-shift gas separator II, and the end of the intermediate conveying pipeline away from the medium-shift gas separator II is connected to the inlet end of the medium-shift gas separator III. The bottom of the medium-shift gas separator I, the bottom of the medium-shift gas separator II and the bottom of the medium-shift gas separator III are all connected to the process condensate recovery pipeline I, and the ends of the three process condensate recovery pipelines I away from the medium-shift gas separator I, the medium-shift gas separator II and the medium-shift gas separator III are commonly connected to a recovery manifold, and the end of the recovery manifold away from the three process condensate recovery pipelines I is connected to the inlet end of the process condensate stripping tower.

[0007] Furthermore, the process condensate recovery pipeline I connected to the bottom of the middle-change gas separator I is connected in series with a liquid level regulating valve I and a liquid level cut-off valve I, and the liquid level regulating valve I is close to the middle-change gas separator I. The process condensate recovery pipeline I connected to the bottom of the middle-change gas separator II is connected in series with a liquid level regulating valve II and a liquid level cut-off valve II, and the liquid level regulating valve II is close to the middle-change gas separator II. The process condensate recovery pipeline I connected to the bottom of the middle-change gas separator III is connected in series with a liquid level regulating valve III and a liquid level cut-off valve III, and the liquid level regulating valve III is close to the middle-change gas separator III.

[0008] Furthermore, a stripping steam pipeline is connected to the upper part of the process condensate stripping tower, and a control valve I is connected to the stripping steam pipeline.

[0009] Furthermore, a process condensate output pipeline is connected to the bottom of the process condensate stripping tower, a process condensate pump is connected to the end of the process condensate output pipeline away from the process condensate stripping tower, an inlet valve is connected to the process condensate output pipeline, an outlet valve is connected to the outlet end of the process condensate pump, an end of the outlet valve away from the process condensate pump is connected to a control valve II through a pipeline, an end of the control valve II away from the outlet valve is connected to a process condensate recovery pipeline II, and a control valve III and a deaerator are sequentially connected to the process condensate recovery pipeline II.

[0010] Furthermore, one end of the control valve II away from the outlet valve is connected to an external discharge pipeline, the external discharge pipeline is connected in parallel with the process condensate recovery pipeline II, and the control valve IV and the sewage treatment plant are connected to the external discharge pipeline in sequence.

[0011] Furthermore, a desalted water preheater is connected to the intermediate transmission pipeline between the intermediate gas-changing separator I and the intermediate gas-changing separator II.

[0012] Furthermore, a medium-transformation gas water cooler and a medium-transformation gas air cooler are sequentially connected to the intermediate transmission pipeline between the medium-transformation gas separator II and the medium-transformation gas separator III.

[0013] Furthermore, the top of the intermediate gas separator III is connected to an intermediate transmission pipeline, and one end of the intermediate transmission pipeline away from the intermediate gas separator III is connected to a PSA3 gas-liquid separator.

[0014] The beneficial effects of the utility model are as follows: the utility model is provided with a process condensate stripping tower, and a stripping steam pipeline feeds 1.0MPa stripping steam into the process condensate stripping tower to remove acidic gases and reduce the pH value of the process condensate; the process condensate is pressurized to 0.6MPa by a process condensate pump and then enters a deaerator through a process condensate recovery pipeline II to prepare boiler feed water, thereby reducing the amount of desalted water used and the cost of hydrogen production, and solving the problems of energy waste, high noise, and serious pollution of surrounding equipment and facilities by the discharged process condensate in the prior art when the process condensate is discharged. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the utility model;

[0016] In the figure: 1. Mid-transformer gas input pipeline; 2. Mid-transformer gas separator I; 3. Liquid level regulating valve I; 4. Liquid level cut-off valve I; 5. Desalted water preheater; 6. Mid-transformer gas separator II; 7. Liquid level regulating valve II; 8. Liquid level cut-off valve II; 9. Mid-transformer gas water cooler; 10. Mid-transformer gas air cooler; 11. Mid-transformer gas separator III; 12. Liquid level regulating valve III; 13. Liquid level cut-off valve III; 14. PSA3 gas-liquid separator; 15. Process condensate return Collection pipeline Ⅰ; 16. Process condensate stripping tower; 17. Control valve Ⅰ; 18. Stripping steam pipeline; 19. Process condensate output pipeline; 20. Inlet valve; 21. Process condensate pump; 22. Outlet valve; 23. Control valve Ⅱ; 24. Process condensate recovery pipeline Ⅱ; 25. Control valve Ⅲ; 26. Deaerator; 27. External discharge pipeline; 28. Control valve Ⅳ; 29. ​​Sewage treatment plant; 30. Intermediate transmission pipeline; 31. Recovery manifold. DETAILED DESCRIPTION

[0017] like Figure 1 As shown, the utility model is a chemical process condensate recycling device comprising

[0018] The intermediate gas input pipeline 1, the process condensate collection unit, and the process condensate stripping tower 16, the process condensate collection unit includes an intermediate gas separator Ⅰ2, an intermediate gas separator Ⅱ6 and an intermediate gas separator Ⅲ11, the intermediate gas separator Ⅰ2, the intermediate gas separator Ⅱ6 and the intermediate gas separator Ⅲ11 are connected in series, the intermediate gas input pipeline 1 is connected to the inlet end of the intermediate gas separator Ⅰ2, the top of the intermediate gas separator Ⅰ2 is connected to the intermediate conveying pipeline 30, the end of the intermediate conveying pipeline 30 away from the intermediate gas separator Ⅰ2 is connected to the inlet end of the intermediate gas separator Ⅱ6, and the top of the intermediate gas separator Ⅱ6 is connected to the intermediate gas separator Ⅲ11. The intermediate transmission pipeline 30, one end of the intermediate transmission pipeline 30 away from the intermediate gas change separator Ⅱ6 is connected to the inlet end of the intermediate gas change separator Ⅲ11, the bottom of the intermediate gas change separator Ⅰ2, the bottom of the intermediate gas change separator Ⅱ6 and the bottom of the intermediate gas change separator Ⅲ11 are all connected with the process condensate recovery pipeline Ⅰ15, the three process condensate recovery pipelines Ⅰ15 have one end away from the intermediate gas change separator Ⅰ2, the intermediate gas change separator Ⅱ6 and the intermediate gas change separator Ⅲ11 and are commonly connected with a recovery manifold 31, and the recovery manifold 31 has one end away from the three process condensate recovery pipelines Ⅰ15 connected to the inlet end of the process condensate stripping tower 16. The process condensate recovery pipeline Ⅰ15 connected to the bottom of the intermediate gas separator Ⅰ2 is connected in series with a liquid level regulating valve Ⅰ3 and a liquid level cut-off valve Ⅰ4, and the liquid level regulating valve Ⅰ3 is close to the intermediate gas separator Ⅰ2. The process condensate recovery pipeline Ⅰ15 connected to the bottom of the intermediate gas separator Ⅱ6 is connected in series with a liquid level regulating valve Ⅱ7 and a liquid level cut-off valve Ⅱ8, and the liquid level regulating valve Ⅱ7 is close to the intermediate gas separator Ⅱ6. The process condensate recovery pipeline Ⅰ15 connected to the bottom of the intermediate gas separator Ⅲ11 is connected in series with a liquid level regulating valve Ⅲ12 and a liquid level cut-off valve Ⅲ13, and the liquid level regulating valve Ⅲ12 is close to the intermediate gas separator Ⅲ11. The upper part of the process condensate stripping tower 16 is connected to a stripping steam pipeline 18, and the stripping steam pipeline 18 is connected to a control valve Ⅰ17. The bottom of the process condensate stripping tower 16 is connected to a process condensate output pipeline 19, and the end of the process condensate output pipeline 19 away from the process condensate stripping tower 16 is connected to a process condensate pump 21, and the process condensate output pipeline 19 is connected to an inlet valve 20, and the outlet end of the process condensate pump 21 is connected to an outlet valve 22, and the end of the outlet valve 22 away from the process condensate pump 21 is connected to a control valve II 23 through a pipeline, and the end of the control valve II 23 away from the outlet valve 22 is connected to a process condensate recovery pipeline II 24, and the process condensate recovery pipeline II 24 is sequentially connected to a control valve III 25 and a deaerator 26. The end of the control valve II 23 away from the outlet valve 22 is connected to an external discharge pipeline 27, and the external discharge pipeline 27 is connected in parallel with the process condensate recovery pipeline II 24, and the external discharge pipeline 27 is sequentially connected to a control valve IV 28 and a sewage treatment plant 29.

[0019] When the utility model is in operation, firstly, the liquid level regulating valve I3 is closed, the liquid level cut-off valve I4 and the liquid level regulating valve I3 are interlocked and put into use, the level regulating valve II7 is closed, the liquid level cut-off valve II8 and the level regulating valve II7 are interlocked and put into use, the liquid level regulating valve III12 is closed, and the liquid level cut-off valve III13 and the liquid level regulating valve III12 are interlocked and put into use. At this time, the liquid level regulating valve I3, the liquid level cut-off valve I4, the liquid level regulating valve II7, the liquid level cut-off valve II8, the liquid level regulating valve III12, and the liquid level cut-off valve III13 are all in a closed state, thereby preventing the intermediate gas from entering the process condensate stripping tower 16 and subsequent pipelines and components;

[0020] When the liquid level in the middle-shift gas separator Ⅰ2, the middle-shift gas separator Ⅱ6 and the middle-shift gas separator Ⅲ11 reaches 10%, open the liquid level cut-off valve Ⅰ4, the liquid level cut-off valve Ⅱ8 and the liquid level cut-off valve Ⅲ13;

[0021] When the liquid level in the middle-shift gas separator Ⅰ2, the middle-shift gas separator Ⅱ6 and the middle-shift gas separator Ⅲ11 reaches 10%, open the liquid level cut-off valve Ⅰ4, the liquid level cut-off valve Ⅱ8 and the liquid level cut-off valve Ⅲ13;

[0022] When the liquid level inside the intermediate gas separator Ⅰ2 reaches 40%, the liquid level regulating valve Ⅰ3 is put into use automatically at 30% to maintain the liquid level of the intermediate gas separator Ⅰ2 not lower than 30%.

[0023] When the liquid level inside the intermediate gas separator Ⅱ6 reaches 35%, the liquid level regulating valve Ⅱ7 is put into use automatically at 30% to keep the liquid level of the intermediate gas separator Ⅰ6 not lower than 30%.

[0024] When the liquid level inside the intermediate gas separator Ⅲ11 reaches 35%, the liquid level regulating valve Ⅲ12 is automatically put into use at 30% to maintain the liquid level of the intermediate gas separator Ⅲ11 not lower than 30%.

[0025] The process condensate in the three process condensate recovery pipelines Ⅰ15 connected to the bottom of the intermediate gas separator Ⅰ2, the bottom of the intermediate gas separator Ⅱ6 and the bottom of the intermediate gas separator Ⅲ11 converges into the recovery manifold 31, and the process condensate in the recovery manifold 31 enters the process condensate stripping tower 16. When the process condensate starts to enter the process condensate stripping tower 16, the control valve Ⅰ17 is opened to allow the stripping steam pipeline 18 to feed 1.0 MPa stripping steam into the process condensate stripping tower 16;

[0026] When the process condensate stripping tower 16 has a 20% liquid level, the inlet valve 20 on the process condensate output pipeline 19 is opened to fill the pump and exhaust, and the process condensate pump 21 is started. The process condensate pump 21 pressurizes the process condensate to 0.6 MPa and then opens the outlet valve 22; when the process condensate stripping tower 16 has a 55% liquid level, the control valve II 23 is opened;

[0027] First, open the control valve IV 28 to allow the process condensate to enter the sewage treatment plant 29 through the external discharge pipeline 27;

[0028] Detect the process condensate flowing into the sewage treatment plant 29. When the pH value of the process condensate is 8-9, close the control valve IV 28 and open the control valve III 25 to allow the process condensate to enter the deaerator 26 through the process condensate recovery pipeline II 24 to prepare boiler feed water;

[0029] At this point, the entire process of condensate recycling is completed.

[0030] A desalted water preheater 5 is connected to the intermediate conveying pipeline 30 between the intermediate gas change separator Ⅰ2 and the intermediate gas change separator Ⅱ6 described in the utility model. The function of the desalted water preheater 5 is to reduce the temperature of the outlet gas of the intermediate gas change separator Ⅰ2, so that a part of the condensate in the intermediate gas change is separated and enters the intermediate gas change separator Ⅱ6 for recovery.

[0031] The intermediate transmission pipeline 30 between the intermediate gas separator Ⅱ6 and the intermediate gas separator Ⅲ11 described in the utility model is connected with the intermediate gas water cooler 9 and the intermediate gas air cooler 10 in sequence. The functions of the intermediate gas water cooler 9 and the intermediate gas air cooler 10 are to reduce the temperature of the outlet gas of the intermediate gas separator Ⅱ6, further separate a part of the condensate in the intermediate gas, and enter the intermediate gas separator Ⅲ11 for recovery.

[0032] The top of the intermediate gas separator III11 described in the utility model is connected to an intermediate conveying pipeline 30, and the end of the intermediate conveying pipeline 30 away from the intermediate gas separator III11 is connected to a PSA3 gas-liquid separator 14. The function of the PSA3 gas-liquid separator 14 is to perform the final separation of the moisture in the intermediate gas entering the PSA3 system to prevent the moisture from entering the PSA3 decarbonization adsorption tower and causing the adsorbent to be pulverized.

[0033] The utility model is provided with a process condensate stripping tower 16, and a stripping steam pipeline 18 feeds 1.0MPa stripping steam into the process condensate stripping tower 16 to remove acidic gases and reduce the pH value of the process condensate. The process condensate is pressurized to 0.6MPa by a process condensate pump 21 and then enters a deaerator 26 through a process condensate recovery pipeline II 24 to prepare boiler feed water, thereby reducing the amount of desalted water and the cost of hydrogen production, and solving the problems of energy waste, high noise, and serious pollution of surrounding equipment and facilities by the discharged process condensate in the prior art when the process condensate is discharged.

Claims

1. A chemical process condensate recycling device, characterized in that: The invention comprises a medium-change gas input pipeline (1), a process condensate collection unit, and a process condensate stripping tower (16). The process condensate collection unit comprises a medium-change gas separator I (2), a medium-change gas separator II (6), and a medium-change gas separator III (11). The medium-change gas separator I (2), the medium-change gas separator II (6), and the medium-change gas separator III (11) are connected in series. The medium-change gas input pipeline (1) is connected to the inlet end of the medium-change gas separator I (2). The top of the medium-change gas separator I (2) is connected to an intermediate transmission pipeline (30). The end of the intermediate transmission pipeline (30) away from the medium-change gas separator I (2) is connected to the inlet end of the medium-change gas separator II (6). The top of the medium-change gas separator II (6) is connected to An intermediate transport pipeline (30), one end of the intermediate transport pipeline (30) away from the intermediate gas separator II (6) is connected to the inlet end of the intermediate gas separator III (11), the bottom of the intermediate gas separator I (2), the bottom of the intermediate gas separator II (6) and the bottom of the intermediate gas separator III (11) are all connected to a process condensate recovery pipeline I (15), one end of the three process condensate recovery pipelines I (15) away from the intermediate gas separator I (2), the intermediate gas separator II (6) and the intermediate gas separator III (11) is commonly connected to a recovery manifold (31), and one end of the recovery manifold (31) away from the three process condensate recovery pipelines I (15) is connected to the inlet end of the process condensate stripping tower (16).

2. The device for recycling condensate for chemical industry according to claim 1, characterized in that: A liquid level regulating valve I (3) and a liquid level shut-off valve I (4) are connected in series to the process condensate recovery pipeline I (15) connected to the bottom of the intermediate gas separator I (2), and the liquid level regulating valve I (3) is close to the intermediate gas separator I (2). A liquid level regulating valve II (7) and a liquid level shut-off valve II (8) are connected in series to the process condensate recovery pipeline I (15) connected to the bottom of the intermediate gas separator II (6), and the liquid level regulating valve II (7) and a liquid level shut-off valve III (13) are connected in series to the process condensate recovery pipeline I (15) connected to the bottom of the intermediate gas separator III (11), and the liquid level regulating valve III (12) and a liquid level shut-off valve III (13) are connected in series to the process condensate recovery pipeline I (15), and the liquid level regulating valve III (12) is close to the intermediate gas separator III (11).

3. The chemical process condensate recycling device according to claim 2, characterized in that: The upper part of the process condensate stripping tower (16) is connected to a stripping steam pipeline (18), and the stripping steam pipeline (18) is connected to a control valve I (17).

4. The device for recycling chemical process condensate according to claim 3, characterized in that: The bottom of the process condensate stripping tower (16) is connected to a process condensate output pipeline (19); one end of the process condensate output pipeline (19) away from the process condensate stripping tower (16) is connected to a process condensate pump (21); an inlet valve (20) is connected to the process condensate output pipeline (19); an outlet valve (22) is connected to the outlet end of the process condensate pump (21); one end of the outlet valve (22) away from the process condensate pump (21) is connected to a control valve II (23) via a pipeline; one end of the control valve II (23) away from the outlet valve (22) is connected to a process condensate recovery pipeline II (24); and a control valve III (25) and a deaerator (26) are sequentially connected to the process condensate recovery pipeline II (24).

5. The device for recycling condensate for chemical industry according to claim 4, characterized in that: The end of the control valve II (23) away from the outlet valve (22) is connected to an external discharge pipeline (27), the external discharge pipeline (27) is connected in parallel with the process condensate recovery pipeline II (24), and the external discharge pipeline (27) is connected in sequence to a control valve IV (28) and a sewage treatment plant (29).

6. The device for recycling condensate for chemical industry according to claim 5, characterized in that: The intermediate transmission pipeline (30) between the intermediate gas-changing separator I (2) and the intermediate gas-changing separator II (6) is connected to a desalted water preheater (5).

7. The device for recycling condensate for chemical industry according to claim 6, characterized in that: The intermediate transmission pipeline (30) between the intermediate gas separator II (6) and the intermediate gas separator III (11) is connected in sequence to an intermediate gas water cooler (9) and an intermediate gas air cooler (10).

8. The device for recycling condensate for chemical industry according to claim 7, characterized in that: The top of the intermediate gas separator III (11) is connected to an intermediate delivery pipeline (30), and one end of the intermediate delivery pipeline (30) away from the intermediate gas separator III (11) is connected to a PSA3 gas-liquid separator (14).

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