Downstream double-effect rectification system based on supergravity technology
By combining atmospheric pressure and negative pressure reboilers in a co-current double-effect distillation system, and utilizing a cascade preheating and vacuum system, the problem of high heat energy consumption in conventional distillation is solved, lower steam consumption and equipment costs are achieved, and separation efficiency and system adaptability are improved.
Patent Information
- Application Number
- CN202521713161.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-13
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2035-08-13
AI Technical Summary
When the conventional distillation process is operated under a single distillation tower, the heat energy consumption is high, resulting in high operating costs.
The system adopts a downstream double-effect distillation system based on supergravity technology. By combining atmospheric pressure and negative pressure reboilers, utilizing cascade preheating components and vacuum system, eliminating intermediate heat exchangers and booster pumps, and utilizing pressure difference for material transportation, efficient preheating and multiple distillations of materials are achieved.
It significantly reduces steam consumption by 30-50%, has lower equipment costs, stronger adaptability, improved separation efficiency, and significant energy-saving effects.
Smart Images
Figure CN223336820U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a double-effect distillation system, in particular to a downstream double-effect distillation system based on supergravity technology. Background Art
[0002] Distillation is an efficient separation technology that utilizes the difference in volatility of components in a mixture to achieve vapor-liquid two-phase mass and heat transfer in a distillation tower through a cyclic operation of heating, vaporization, condensation and reflux, ultimately obtaining light components at the top of the tower and heavy components at the bottom of the tower.
[0003] The conventional process requires a single distillation tower to operate at normal pressure or negative pressure, and its heat energy consumption is mainly concentrated in the steam supply of the reboiler, resulting in high operating costs. Utility Model Content
[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a downstream double-effect distillation system based on supergravity technology.
[0005] In order to achieve the above-mentioned purpose, the utility model provides the following technical solutions: a high-pressure distillation unit, including an atmospheric-pressure reboiler and an atmospheric-pressure distillation supergravity machine connected to each other; a negative-pressure distillation unit, including a negative-pressure reboiler, a negative-pressure distillation supergravity machine and a vacuum system connected to each other; a heat transfer pipeline: the atmospheric-pressure distillation supergravity machine has an atmospheric-pressure supergravity steam outlet, the negative-pressure reboiler has a negative-pressure reboiler steam inlet, the atmospheric-pressure supergravity steam outlet is connected to the negative-pressure reboiler steam inlet, the downstream material channel: the atmospheric-pressure reboiler has an atmospheric-pressure reboiler material outlet, the negative-pressure distillation supergravity machine has a negative-pressure supergravity material inlet, the atmospheric-pressure reboiler material outlet is connected to the negative-pressure reboiler steam inlet, the downstream material channel is connected to the atmospheric-pressure reboiler material outlet, the negative-pressure distillation supergravity machine has a negative-pressure supergravity material inlet, the atmospheric-pressure reboiler material outlet is connected to the negative-pressure reboiler steam ... The outlet is connected to the negative pressure supergravity material inlet through a pipeline and there is no booster pump in the middle of the pipeline; the cascade preheating component: includes a first preheater and a second preheater connected in series, wherein: the second preheater has a second cold side inlet and a second hot side inlet, the second cold side inlet is connected to the external material, and the second hot side inlet is connected to the negative pressure distillation supergravity machine; the first preheater has a first cold side inlet, a first cold side outlet and a first hot side inlet, the first cold side inlet is connected to the second cold side outlet, the first hot side inlet is connected to the atmospheric pressure supergravity distillation machine and the negative pressure reboiler, and the first cold side outlet is connected to the atmospheric pressure distillation supergravity machine.
[0006] By adopting the above technical solution, the material enters the second preheater through the second cold side inlet for the first preheating, and after completion, enters the first preheater through the second cold side outlet and the first cold side inlet for the second preheating, completing the preheating of the material, and then enters the atmospheric distillation supergravity machine. At the same time, the heat source heats the atmospheric pressure reboiler through the heat source port, so that the steam enters the atmospheric pressure distillation supergravity machine, and heats the material in the atmospheric pressure distillation supergravity machine. After the atmospheric distillation is completed, the material enters the atmospheric pressure reboiler for heating, and then enters the negative pressure distillation supergravity machine for secondary distillation. At the same time, the steam in the atmospheric distillation supergravity first provides a heat source to the negative pressure reboiler through the atmospheric pressure supergravity outlet, and then enters the first preheater, and the steam in the negative pressure reboiler then enters the negative pressure reboiler. In the high-pressure distillation supergravity machine, the material in it is heated. When the material completes negative pressure distillation, the material enters the negative pressure reboiler and is then produced. The steam in the negative pressure distillation supergravity machine enters the second preheater. Since the temperature in the second preheater is lower than that in the first preheater, the material passes through the second preheater first and then the first preheater, which has higher heating efficiency. The step preheating fully recovers the steam of the negative pressure distillation supergravity machine and the waste heat of condensation in the negative pressure reboiler, and the comprehensive energy saving rate exceeds 30%. The steam of the atmospheric distillation supergravity machine directly supplies heat to the negative pressure reboiler, eliminating the intermediate heat exchanger and reducing steam consumption by 10-15%. Compared with the countercurrent type, the co-current type has no booster pump between the atmospheric reboiler and the negative pressure distillation supergravity machine, but flows according to the direction of pressure reduction, and the equipment cost is lower.
[0007] The utility model is further configured as follows: the atmospheric pressure reboiler also has a heat source port, an atmospheric pressure reboiler steam outlet and an atmospheric pressure reboiler material inlet; the atmospheric pressure distillation supergravity machine also has an atmospheric pressure supergravity steam inlet, an atmospheric pressure supergravity material inlet and an atmospheric pressure supergravity material outlet; the heat source port is connected to an external heat source; the atmospheric pressure reboiler steam outlet is communicated with the atmospheric pressure supergravity steam inlet and transfers steam from the atmospheric pressure reboiler to the atmospheric pressure distillation supergravity machine; the atmospheric pressure reboiler material inlet is communicated with the atmospheric pressure supergravity material outlet and transfers material from the atmospheric pressure distillation supergravity machine to the atmospheric pressure reboiler; the atmospheric pressure supergravity material inlet is connected to the first cold side outlet and transfers material from the first preheater to the atmospheric pressure distillation supergravity machine.
[0008] The utility model is further configured as follows: the negative pressure reboiler also has a negative pressure reboiler material inlet, a negative pressure reboiler material outlet, a negative pressure reboiler steam outlet and a negative pressure reboiler heat source outlet; the negative pressure distillation supergravity machine also has a negative pressure supergravity material outlet, a negative pressure supergravity steam inlet and a negative pressure supergravity steam outlet; the negative pressure reboiler material inlet is connected to the negative pressure supergravity material outlet, the negative pressure reboiler material outlet is connected to the outside world, the negative pressure reboiler steam outlet is connected to the negative pressure supergravity steam inlet, the negative pressure supergravity steam outlet is connected to the second hot side inlet, and the negative pressure reboiler heat source outlet is connected to the first hot side inlet.
[0009] The utility model is further configured as follows: a diaphragm pump is provided between the negative pressure reboiler and the first preheater.
[0010] The utility model is further configured as follows: the height of the negative pressure reboiler heat source outlet is higher than the height of the first hot side.
[0011] By adopting the above technical solution, no pump is used, and the gravity generated by the height difference is used to complete the transportation.
[0012] The utility model is further configured as follows: the operating pressure of the vacuum system is -0.03MPa to -0.095MPa.
[0013] By adopting the above technical solutions, the vacuum range balances energy consumption and separation efficiency, avoiding a surge in high vacuum energy consumption.
[0014] The utility model is further configured as follows: the atmospheric pressure reboiler and the negative pressure reboiler are both vertical or horizontal structures.
[0015] By adopting the above technical solutions, the vertical structure saves space and is suitable for small flow rates and high-boiling-point materials; the horizontal structure facilitates uniform heating of large flow rates and prevents coking; it is compatible with different working conditions and improves system adaptability. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a schematic diagram of the overall structure of the utility model including a diaphragm pump;
[0017] Figure 2 This is a schematic diagram of the overall structure of the utility model without the diaphragm pump.
[0018] In the figure: 1. Atmospheric pressure distillation supergravity machine; 11. Atmospheric pressure supergravity steam outlet; 12. Atmospheric pressure supergravity steam inlet; 13. Atmospheric pressure supergravity material inlet; 14. Atmospheric pressure supergravity material outlet; 2. Atmospheric pressure reboiler; 21. Atmospheric pressure reboiler material outlet; 22. Heat source outlet; 23. Atmospheric pressure reboiler steam outlet; 24. Atmospheric pressure reboiler material inlet; 3. Negative pressure distillation supergravity machine; 31. Negative pressure supergravity material inlet; 32. Negative pressure supergravity material outlet; 33. Negative pressure supergravity steam inlet; 3 4. Negative pressure supergravity steam outlet; 4. Negative pressure reboiler; 41. Negative pressure reboiler steam inlet; 42. Negative pressure reboiler material inlet; 43. Negative pressure reboiler material outlet; 44. Negative pressure reboiler steam outlet; 45. Negative pressure reboiler heat source outlet; 5. Vacuum system; 6. Second preheater; 61. Second cold side inlet; 62. Second hot side inlet; 63. Second cold side outlet; 7. First preheater; 71. First cold side inlet; 72. First cold side outlet; 73. First hot side inlet; 8. Diaphragm pump. DETAILED DESCRIPTION
[0019] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.
[0020] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0021] like Figure 1-2As shown, the utility model discloses a downstream double-effect distillation system based on supergravity technology, a high-pressure distillation unit, including an atmospheric reboiler 2 and an atmospheric distillation supergravity machine 1 connected to each other; a negative pressure distillation unit, including a negative pressure reboiler 4, a negative pressure distillation supergravity machine 3 and a vacuum system 5 connected to each other; a heat transfer pipeline: the atmospheric distillation supergravity machine 1 has an atmospheric supergravity steam outlet 11, the negative pressure reboiler 4 has a negative pressure reboiler steam inlet 41, the atmospheric supergravity steam outlet 11 is connected to the negative pressure reboiler steam inlet 41, the downstream material channel: the atmospheric reboiler 2 has an atmospheric reboiler material outlet 21, the negative pressure distillation supergravity machine 3 has a negative pressure supergravity material inlet 31, and the atmospheric reboiler material outlet 21 and the negative pressure supergravity material inlet 31 are connected through a pipeline. The first preheater 7 is connected to the second preheater 6 and the second preheater 6 is connected in series, wherein: the second preheater 6 has a second cold side inlet 61 and a second hot side inlet 62, the second cold side inlet 61 is connected to the external material, and the second hot side inlet 62 is connected to the negative pressure distillation supergravity machine 3; the first preheater 7 has a first cold side inlet 71, a first cold side outlet 72 and a first hot side inlet 73, the first cold side inlet 71 is connected to the second cold side outlet, the first hot side inlet 73 is connected to the atmospheric pressure supergravity distillation machine and the negative pressure reboiler 4, the first cold side outlet 72 is connected to the atmospheric pressure distillation supergravity machine 1, and the material enters the second preheater 6 through the second cold side inlet 61 for the first preheating, and then passes through the second cold side outlet to the first A cold side inlet 71 enters the first preheater 7 for secondary preheating to complete the preheating of the material, and then enters the atmospheric distillation supergravity machine 1. At the same time, the heat source heats the atmospheric reboiler 2 through the heat source port 22, so that the steam enters the atmospheric distillation supergravity machine 1 to heat the material in the atmospheric distillation supergravity machine 1. After the atmospheric distillation is completed, the material enters the atmospheric reboiler 2 for heating, and then enters the negative pressure distillation supergravity machine 3 for secondary distillation. At the same time, the steam in the atmospheric distillation supergravity first provides a heat source to the negative pressure reboiler 4 through the atmospheric supergravity outlet, and then enters the first preheater 7, and the steam in the negative pressure reboiler 4 then enters the negative pressure distillation supergravity machine 3 to heat the material therein. When the material After completing the negative pressure distillation, the material enters the negative pressure reboiler 4 and is then produced, while the steam in the negative pressure distillation supergravity machine 3 enters the second preheater 6. Since the temperature in the second preheater 6 is lower than the temperature in the first preheater 7, the material first passes through the second preheater 6 and then through the first preheater 7, which has higher heating efficiency. The step preheating fully recovers the steam from the negative pressure distillation supergravity machine 3 and the condensation waste heat of the negative pressure reboiler 4, and the comprehensive energy saving rate exceeds 30%; the steam from the atmospheric distillation supergravity machine 1 directly supplies heat to the negative pressure reboiler 4, eliminating the intermediate heat exchanger and reducing steam consumption by 10-15%. Compared with the countercurrent type, the cocurrent type has no booster pump between the atmospheric pressure reboiler 2 and the negative pressure distillation supergravity machine 3, but flows in the direction of pressure reduction, and the equipment cost is lower.
[0022] The atmospheric pressure reboiler 2 also has a heat source port 22, an atmospheric pressure reboiler steam outlet 23 and an atmospheric pressure reboiler material inlet 24. The atmospheric pressure distillation supergravity machine 1 also has an atmospheric pressure supergravity steam inlet 12, an atmospheric pressure supergravity material inlet 13 and an atmospheric pressure supergravity material outlet 14. The heat source port 22 is connected to an external heat source. The atmospheric pressure reboiler steam outlet 23 is connected to the atmospheric pressure supergravity steam inlet 12 and transfers steam from the atmospheric pressure reboiler 2 to the atmospheric pressure distillation supergravity machine 1. The atmospheric pressure reboiler material inlet 24 is connected to the atmospheric pressure supergravity material outlet 14 and transfers material from the atmospheric pressure distillation supergravity machine 1 to the atmospheric pressure reboiler 2. The atmospheric pressure supergravity material inlet 13 is connected to the first cold side outlet 72 and transfers material from the first preheater 7 to the atmospheric pressure distillation supergravity machine 1.
[0023] The negative pressure reboiler 4 also has a negative pressure reboiler material inlet 42, a negative pressure reboiler material outlet 43, a negative pressure reboiler steam outlet 44 and a negative pressure reboiler heat source outlet 45. The negative pressure distillation supergravity machine 3 also has a negative pressure supergravity material outlet 32, a negative pressure supergravity steam inlet 33 and a negative pressure supergravity steam outlet 34. The negative pressure reboiler material inlet 42 is connected to the negative pressure supergravity material outlet 32, the negative pressure reboiler material outlet 43 is connected to the outside world, the negative pressure reboiler steam outlet 44 is connected to the negative pressure supergravity steam inlet 33, the negative pressure supergravity steam outlet 34 is connected to the second hot side inlet 62, and the negative pressure reboiler heat source outlet 45 is connected to the first hot side inlet 73.
[0024] A diaphragm pump 8 is provided between the negative pressure reboiler 4 and the first preheater 7 .
[0025] The height of the negative pressure reboiler heat source outlet 45 is higher than that of the first hot side, and no pump is used, but gravity generated by the height difference is used to complete the transportation.
[0026] The operating pressure of the vacuum system 5 is -0.03 MPa to -0.095 MPa. The vacuum range balances energy consumption and separation efficiency to avoid a surge in high vacuum energy consumption.
[0027] Both the atmospheric reboiler 2 and the negative pressure reboiler 4 are of vertical or horizontal structure. The vertical structure saves space and is suitable for small flow rate high boiling point materials; the horizontal structure facilitates uniform heating of large flow rate materials and prevents coking; it is compatible with different working conditions and improves system adaptability.
[0028] The distillation process of this scheme is based on a feed of 1000 kg / h, 30°C, 4% DMAC + water raw material liquid, a reflux ratio of 0.2, a normal negative pressure process of 0.2, and a water output of 878.055 kg / h; the operating pressure is respectively atmospheric pressure and -60 kPag. After distillation in this way, the raw material is concentrated from 4% DMAC + water to 32.8% DMAC + water, the water removal rate is 91.46%, and the heat energy consumption is 310560 kcal / h;
[0029] The single-effect distillation process under the same conditions, with a feed rate of 1000 kg / h, 30°C, 4% DMAC + water raw material liquid, and a reflux ratio of 0.2; the pressure reference double-effect distillation process is -60 kPag. The raw material is concentrated from 4% DMAC + water to 32.8% DMAC + water, with a water removal rate of 91.46% and a heat energy consumption of 635,300 kcal / h;
[0030] In summary, energy saving is 51.12% year-on-year
[0031] Working process: the material enters the second preheater 6 through the second cold side inlet 61 for the first preheating, and then enters the first preheater 7 through the second cold side outlet and the first cold side inlet 71 for the second preheating to complete the preheating of the material, and then enters the atmospheric distillation supergravity machine 1. At the same time, the heat source heats the atmospheric reboiler 2 through the heat source port 22, so that the steam enters the atmospheric distillation supergravity machine 1, and heats the material in the atmospheric distillation supergravity machine 1. After the atmospheric distillation is completed, the material enters the atmospheric distillation supergravity machine 1. It is heated in the reboiler 2 and then enters the negative pressure distillation supergravity machine 3 for secondary distillation. At the same time, the steam in the atmospheric distillation supergravity first provides a heat source to the negative pressure reboiler 4 through the atmospheric pressure supergravity outlet, and then enters the first preheater 7. The steam in the negative pressure reboiler 4 then enters the negative pressure distillation supergravity machine 3 to heat the material therein. When the material completes the negative pressure distillation, the material enters the negative pressure reboiler 4 and is then output, and the steam in the negative pressure distillation supergravity machine 3 enters the second preheater 6.
Claims
1. A downstream double-effect distillation system based on high gravity technology, characterized by: An atmospheric distillation unit, comprising an atmospheric reboiler (2) and an atmospheric distillation supergravity machine (1) connected thereto; A negative pressure distillation unit comprising a connected negative pressure reboiler (4), a negative pressure distillation supergravity machine (3) and a vacuum system (5); Heat transfer pipeline: the atmospheric distillation supergravity machine (1) has an atmospheric supergravity steam outlet (11), the negative pressure reboiler (4) has a negative pressure reboiler steam inlet (41), and the atmospheric supergravity steam outlet (11) is connected to the negative pressure reboiler steam inlet (41). Downstream material channel: the atmospheric pressure reboiler (2) has an atmospheric pressure reboiler material outlet (21), the negative pressure distillation supergravity machine (3) has a negative pressure supergravity material inlet (31), the atmospheric pressure reboiler material outlet (21) and the negative pressure supergravity material inlet (31) are connected by a pipeline, and there is no booster pump in the middle of the pipeline; The cascade preheating assembly comprises a first preheater (7) and a second preheater (6) connected in series, wherein: The second preheater (6) has a second cold side inlet (61), a second hot side inlet (62) and a second cold side outlet (63), the second cold side inlet (61) is connected to external materials, and the second hot side inlet (62) is connected to the negative pressure distillation supergravity machine (3); The first preheater (7) has a first cold side inlet (71), a first cold side outlet (72) and a first hot side inlet (73), the first cold side inlet (71) is connected to the second cold side outlet (63), the first hot side inlet (73) is connected to the atmospheric pressure supergravity distillation machine and the negative pressure reboiler (4), and the first cold side outlet (72) is connected to the atmospheric pressure distillation supergravity machine (1).
2. The downstream double-effect distillation system based on high gravity technology according to claim 1, characterized in that: The atmospheric pressure reboiler (2) further comprises a heat source port (22), an atmospheric pressure reboiler steam outlet (23) and an atmospheric pressure reboiler material inlet (24); the atmospheric pressure distillation supergravity machine (1) further comprises an atmospheric pressure supergravity steam inlet (12), an atmospheric pressure supergravity material inlet (13) and an atmospheric pressure supergravity material outlet (14); the heat source port (22) is connected to an external heat source; the atmospheric pressure reboiler steam outlet (23) is connected to the atmospheric pressure supergravity steam inlet (12) and transfers steam from the atmospheric pressure reboiler (2) to the atmospheric pressure distillation supergravity machine (1); the atmospheric pressure reboiler material inlet (24) is connected to the atmospheric pressure supergravity material outlet (14) and transfers material from the atmospheric pressure distillation supergravity machine (1) to the atmospheric pressure reboiler (2); and the atmospheric pressure supergravity material inlet (13) is connected to the first cold side outlet (72) and transfers material from the first preheater (7) to the atmospheric pressure distillation supergravity machine (1).
3. The downstream double-effect distillation system based on high gravity technology according to claim 2, characterized in that: The negative pressure reboiler (4) further comprises a negative pressure reboiler material inlet (42), a negative pressure reboiler material outlet (43), a negative pressure reboiler steam outlet (44) and a negative pressure reboiler heat source outlet (45); the negative pressure distillation supergravity machine (3) further comprises a negative pressure supergravity material outlet (32), a negative pressure supergravity steam inlet (33) and a negative pressure supergravity steam outlet (34); the negative pressure reboiler material inlet (42) is connected to the negative pressure supergravity material outlet (32); the negative pressure reboiler material outlet (43) is connected to the outside; the negative pressure reboiler steam outlet (44) is connected to the negative pressure supergravity steam inlet (33); the negative pressure supergravity steam outlet (34) is connected to the second hot side inlet (62); and the negative pressure reboiler heat source outlet (45) is connected to the first hot side inlet (73).
4. The downstream double-effect distillation system based on high gravity technology according to claim 3, characterized in that: A diaphragm pump (8) is provided between the negative pressure reboiler (4) and the first preheater (7).
5. The downstream double-effect distillation system based on high gravity technology according to claim 3, characterized in that: The height of the negative pressure reboiler heat source outlet (45) is higher than the height of the first hot side.
6. The downstream double-effect distillation system based on high gravity technology according to claim 1, characterized in that: The operating pressure of the vacuum system (5) is -0.03 MPa to -0.095 MPa.
7. The downstream double-effect distillation system based on high gravity technology according to claim 1, characterized in that: The atmospheric pressure reboiler (2) and the negative pressure reboiler (4) are both vertical or horizontal structures.