Rectification system of cyclopentane
By combining a pre-distillation column, an extractive distillation column, a light component removal column, and a heavy component distillation column, the problem of separating cyclopentane from 2,2-dimethylbutane was solved, achieving the separation of high-purity cyclopentane and a high yield.
Patent Information
- Application Number
- CN202423299040.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2034-12-31
AI Technical Summary
Cyclopentane and 2,2-dimethylbutane are difficult to separate by ordinary distillation, resulting in low purity of cyclopentane.
A combined system of pre-distillation column, extractive distillation column, light hydrocarbon removal column and heavy hydrocarbon removal column is adopted. Heavy aromatic hydrocarbons are removed by pre-distillation, the material pressure is increased by pressurizing and regulating heat exchangers, and high-purity cyclopentane and 2,2-dimethylbutane are separated by combining three-dimensional mass transfer trays.
The purity of cyclopentane reached 99.96%, the yield reached 95%, and the material recycling capacity was improved.
Smart Images
Figure CN223716392U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to cyclopentane rectification equipment technical field, specifically related to a cyclopentane rectification system. BACKGROUND
[0002] Cyclopentane (C5H 12 ) is a kind of organic compound commonly used in petrochemical industry, widely used in solvent, lubricating oil, fuel additive and refrigerator freezer insulation material and rigid PU foam foaming agent etc. In the preparation of cyclopentane, the mixed hydrocarbon containing cyclopentane after light removal is usually rectified to separate high-purity cyclopentane, especially to separate cyclopentane from 2,2-dimethylbutane.
[0003] However, the boiling point of cyclopentane is 49.25 DEG C, and the boiling point of 2,2-dimethylbutane is 49.74 DEG C, with a difference of 0.49 DEG C. They are not only near-boiling system, but also azeotropic system, and the relative volatility is close to 1. High-purity cyclopentane monomer cannot be obtained by ordinary rectification.
[0004] Therefore, the present application aims to provide a cyclopentane rectification system to solve the problems of difficult separation of cyclopentane and 2,2-dimethylbutane and low purity of cyclopentane. UTILITY MODEL CONTENT
[0005] The utility model provides a cyclopentane rectification system to solve the above technical problems in the prior art.
[0006] The utility model solves the above technical problems by the following technical scheme: a cyclopentane rectification system, comprising an extractive rectification tower, characterized by that a pre-rectification tower is arranged at the input side of the extractive rectification tower, a light removal tower is connected to the top output side of the extractive rectification tower, and a heavy distillation tower is connected to the bottom output side of the light removal tower.
[0007] The input side of the pre-rectification tower is connected to a raw material tank and a pre-rectification feed intermediate tank, the bottom of the pre-rectification tower is connected to a crude non-aromatic hydrocarbon storage tank, the top of the pre-rectification tower is connected to an extractive tower feed tank, and the extractive tower feed tank is connected to the extractive rectification tower.
[0008] The top of the extractive rectification tower is connected to a cyclopentane feed tank, and the cyclopentane feed tank is connected to the light removal tower.
[0009] The input side of the light removal tower is connected to the cyclopentane feed tank through a feed pressurizing heat exchanger, the top output of the light removal tower has two routes, one of which is refluxed to the top of the light removal tower, and the other is connected to a non-aromatic hydrocarbon product tank, and the bottom of the light removal tower is connected to the heavy distillation tower.
[0010] The input side of the distillation column is connected to the bottom of the light-removing column through a feed pressure regulating heat exchanger, two routes are output from the top of the distillation column, one of which is returned to the top of the distillation column, and the other is connected to a cyclopentane product tank; the side line of the distillation column is connected to a 2,2-dimethylbutane recovery tank; two routes are output from the bottom of the distillation column, one of which is connected to a non-aromatic hydrocarbon storage tank, and the other is connected to the pre-fractionation feed intermediate tank.
[0011] Further, the bottom of the light-removing column is connected with a bottom reboiler; the top of the light-removing column is connected with an evaporative cooler, the evaporative cooler is connected with a cooler, the cooler is connected to a reflux tank, and the reflux tank is connected to two routes through a light-removing column reflux pump, one of which is returned to the top of the light-removing column, and the other is connected to a non-aromatic hydrocarbon product tank.
[0012] Further, the bottom of the light-removing column is provided with a bottom production pump, which is connected to the distillation column through a feed pressure regulating heat exchanger.
[0013] Further, after the bottom of the light-removing column is taken out through the bottom production pump, a feed pressure regulating heat exchanger connected to the light-removing column provides heat exchange for it, and then connects to the distillation column through a feed pressure regulating heat exchanger.
[0014] Further, the bottom of the distillation column is connected with a bottom reboiler; the top of the distillation column is connected with an evaporative cooler, the evaporative cooler is connected with a cooler, the cooler is connected to a reflux tank, and the reflux tank is connected to two routes through a distillation column reflux pump, one of which is returned to the top of the distillation column, and the other is connected to a cyclopentane product tank; the bottom of the distillation column is taken out through a bottom production pump.
[0015] Further, a three-dimensional mass transfer tray is used in the distillation column, the theoretical tray number is 80-120, and the opening rate of the rising hole of the tray is 14%±0.2%.
[0016] Further, the top of the pre-fractionation column is connected with a cooler and a reflux tank, and two routes are divided from the reflux tank, one of which is returned to the top of the pre-fractionation column, and the other is connected to the extractive distillation column.
[0017] The utility model discloses beneficial effect is: the utility model discloses through adding pre rectifying tower before extraction rectifying tower, to remove part heavy aromatic hydrocarbon class material, then the material after extraction enters light removal tower, distillation heavy tower in proper order, especially through adding feed pressurization heat exchanger before light removal tower feed, adding feed pressure regulating heat exchanger before distillation heavy tower feed, improve the pressure of entering light removal tower material and adjust the pressure of entering distillation heavy tower material, finally through distillation heavy tower overhead extraction cyclopentane, distillation heavy tower side line separation recovery 2, 2 - dimethyl butane, distillation heavy tower bottom extraction divides two roads, wherein one road is transported to non aromatic hydrocarbon storage tank, another road is transported to pre rectifying feed intermediate tank, as one of pre rectifying raw material, through the pipeline design of this device is more reasonable, and material recycling is better, and finally separates cyclopentane, 2, 2 - dimethyl butane respectively, and the purity of cyclopentane can reach 99.96%, and the yield reaches 95%. BRIEF DESCRIPTION OF DRAWINGS
[0018] BRIEF DESCRIPTION OF DRAWINGS Figure 1 It is the system overall structure schematic diagram of the utility model, and the system overall structure schematic diagram of the utility model is as shown in the figure.
[0019] BRIEF DESCRIPTION OF DRAWINGS Figure 2 It is the connecting structure schematic diagram of light removal tower of the utility model.
[0020] BRIEF DESCRIPTION OF DRAWINGS Figure 3 It is the connecting structure schematic diagram of distillation heavy tower of the utility model.
[0021] BRIEF DESCRIPTION OF DRAWINGS Figure 4 It is the process flow diagram based on the rectifying system of the utility model.
[0022] Among them:
[0023] BRIEF DESCRIPTION OF DRAWINGS Figure 1 Among them: 100, pre rectifying tower, 200, extraction rectifying tower, 300, light removal tower, 400, distillation heavy tower, 101, raw material tank, 102, pre rectifying feed intermediate tank, 103, crude non aromatic hydrocarbon storage tank, 201, extraction tower feed tank, 301, cyclopentane feed tank, 302, non aromatic hydrocarbon product tank, 401, cyclopentane product tank, 402, 2, 2 - dimethyl butane recovery tank, 403, non aromatic hydrocarbon storage tank.
[0024] BRIEF DESCRIPTION OF DRAWINGS Figure 2 Among them: 11, cyclopentane light removal tower, 12, bottom reboiler, 13, feed pressurization heat exchanger, 14, evaporative cooler, 15, cooler, 16, reflux tank, 7A, bottom extraction pump A pump (cyclopentane refining feed pump), 7B, bottom extraction pump B pump (cyclopentane refining feed pump), 8A, cyclopentane light removal tower reflux pump A pump, 8B, cyclopentane light removal tower reflux pump B pump.
[0025] BRIEF DESCRIPTION OF DRAWINGS Figure 3Middle: 21, cyclopentane distillation heavy tower, 22, tower bottom reboiler, 23, evaporative cooler, 24, cooler, 25, reflux tank, 26, production cooler, 7A, tower bottom production pump A pump, 7B, tower bottom production pump B pump, 8A, cyclopentane distillation heavy tower reflux pump A pump, 8B, cyclopentane distillation heavy tower reflux pump B pump, 29, feed pressure regulating heat exchanger. DETAILED DESCRIPTION
[0026] The principle and characteristics of the utility model will be described below, and the examples are only used to explain the utility model, and are not used to limit the scope of the utility model.
[0027] The cyclopentane rectification system of the embodiment is shown in Figure 1 Fig. 1, which comprises pre-distillation tower 100, extractive distillation tower 200, light removal tower 300 and distillation heavy tower 400 connected in turn along the production line direction, wherein pre-distillation tower 100 and extractive distillation tower 200 are respectively distillation tower and extractive tower of the prior art.
[0028] The raw material enters pre-distillation tower 100 through a pump, and the raw material comes from raw material tank 101 and pre-distillation feed intermediate tank 102 arranged on the feed side of pre-distillation tower 100; the bottom of pre-distillation tower 100 is connected to crude non-aromatic hydrocarbon storage tank 103, and the top of pre-distillation tower 100 is connected to cooler and reflux tank, and two routes are divided from the reflux tank, one of which is refluxed to the top of pre-distillation tower, and the other is connected to extractive tower feed tank 201, which is connected to extractive distillation tower 200.
[0029] The top of the extractive distillation tower 200 is connected to the cyclopentane feed tank 301, and the cyclopentane feed tank 301 is connected to the light removal tower 300.
[0030] As shown in Figure 2 , the light removal tower 300, i.e. cyclopentane light removal tower 11, has a tower bottom reboiler 12 connected to its bottom; the input side of the light removal tower 300 is connected to the cyclopentane feed tank 301 through a feed pressure exchanger 13 (specifically a floating head heat exchanger); the top of the light removal tower 300 is connected to an evaporative cooler 14, and the evaporative cooler 14 is connected to a cooler 15 for double deep cooling, and the cooler 15 is connected to a reflux tank 16, which is connected to two routes through light removal tower reflux pumps (8A, 8B) therein, one of which is refluxed to the top of the light removal tower 300, and the other is connected to non-aromatic hydrocarbon product tank 302; the bottom of the light removal tower 300 is pumped out by tower bottom production pumps (7A, 7B) therein and sent to distillation heavy tower 400. Figure 2 Figure 2
[0031] As shown in Figure 3 As shown, the heavy distillation column 400, also known as the cyclopentane heavy distillation column 21, has a bottom reboiler 22 connected to its bottom. The input side of the heavy distillation column 400 is connected to the bottom of the light distillation column via a feed pressure regulating heat exchanger 29 (specifically, a tube sheet heat exchanger, with the material pressure entering the heavy distillation column 400 regulated by water flow control). The top of the heavy distillation column 400 is connected to an evaporative cooler 23, which is connected to a cooler 24 for double deep cooling. The cooler 24 is connected to a reflux tank 25, which is connected to a heavy distillation column reflux pump (…). Figure 3 8A and 8B in the diagram connect two lines, one of which refluxes to the top of the heavy distillation column 400, and the other connects to the cyclopentane product tank 401; the side line of the heavy distillation column 400 connects to the 2,2-dimethylbutane recovery tank 402; the bottom of the heavy distillation column 400 is collected by the bottom pump (…). Figure 3 The feed from 7A and 7B is divided into two streams. One stream connects to the non-aromatic hydrocarbon storage tank 403, and the other stream connects to the pre-distillation feed intermediate tank 102, serving as one of the raw materials for pre-distillation. In this embodiment, the distillation column has a built-in three-dimensional mass transfer tray with a theoretical number of trays of 80-120 and an opening rate of 14% ± 0.2% for the rising gas vents on the trays.
[0032] In this embodiment, the bottom of the light-light removal tower 300 is collected by the bottom pump and connected to the feed pressurization heat exchanger 13 of the light-light removal tower 300 to provide heat exchange. Then, it is connected to the heavy distillation tower 400 via the feed pressure regulating heat exchanger 29 to deliver heavy distillation feed at a suitable pressure to the heavy distillation tower 400.
[0033] In the working state, the raw material mixed aromatic hydrocarbon enters the pre-distillation column 100 from the raw material tank 101, and is pre-distilled to remove part of heavy aromatic hydrocarbon, and then the mixture after pre-distillation is punched into the extractive distillation column 200, and through the complex reaction with the extractant, the benzene ring aromatic hydrocarbon is removed; the extracted material is transported to the cyclopentane feed tank 301, and then enters the light removal column 300 through the pressurized heat exchanger 13, the non-aromatic hydrocarbon vapor collected from the top of the light removal column 300 is cooled by the cooler and then enters the cyclopentane light removal column reflux tank, part of which is used as the top reflux through the cyclopentane light removal column reflux pump, and the other part is transported to the non-aromatic hydrocarbon storage tank 302, the material collected from the bottom of the light removal column 300 is first heated by the feed pressurized heat exchanger 13, and then enters the cyclopentane distillation column 400 after being adjusted by the feed pressure regulating heat exchanger 29; the cyclopentane vapor collected from the top of the distillation column 400 is cooled by the distillation column 400 top air cooler and then enters the cyclopentane distillation column reflux tank, part of which is used as the top reflux through the cyclopentane distillation column reflux pump, and the other part is transported to the cyclopentane product tank 401, 2,2-dimethylbutane is recovered through the side line separation of the cyclopentane distillation column, and the material collected from the bottom of the distillation column 400 is divided into two parts, one of which is transported to the non-aromatic hydrocarbon storage tank 403, and the other is transported to the pre-distillation feed intermediate tank 102 as one of the pre-distillation raw materials, which is recycled. The purity of cyclopentane produced by the device of the utility model is as high as 99.96%, and the yield can reach 95%.
[0034] The raw material mixed aromatic hydrocarbon of the embodiment is composed of the following components:
[0035]
[0036] The above is only the detailed description of the preferred embodiments of the utility model, but not to limit the utility model, for the person skilled in the art, without departing from the spirit and scope of the utility model, can also make a number of modifications and improvements, therefore, the protection scope of the utility model should be limited by the range of claims.
Claims
1. A rectification system of cyclopentane comprising an extractive rectification column, characterized in that, The input side of the extractive rectification tower is provided with a pre-rectification tower, the top output side of the extractive rectification tower is connected with a light-removing tower, and the bottom output side of the light-removing tower is connected with a heavy-removing tower. The input side of the pre-rectification tower is connected with a raw material tank and a pre-rectification feed intermediate tank, the bottom of the pre-rectification tower is connected to a crude non-aromatic hydrocarbon storage tank, the top of the pre-rectification tower is connected to an extractive tower feed tank, and the extractive tower feed tank is connected to the extractive rectification tower. The top of the extractive rectification tower is connected to a cyclopentane feed tank, and the cyclopentane feed tank is connected to the light-removing tower. The input side of the light-removing tower is connected to the cyclopentane feed tank through a feed pressurizing heat exchanger, the top output of the light-removing tower is branched into two routes, one of which is refluxed to the top of the light-removing tower, and the other is connected to a non-aromatic hydrocarbon product tank, and the bottom of the light-removing tower is connected to the heavy-removing tower. The input side of the heavy-removing tower is connected to the bottom of the light-removing tower through a feed pressure regulating heat exchanger, the top output of the heavy-removing tower is branched into two routes, one of which is refluxed to the top of the heavy-removing tower, and the other is connected to a cyclopentane product tank; a side line of the heavy-removing tower is connected to a 2,2-dimethylbutane recovery tank; the bottom output of the heavy-removing tower is branched into two routes, one of which is connected to a non-aromatic hydrocarbon storage tank, and the other is connected to the pre-rectification feed intermediate tank.
2. The rectification system of cyclopentane according to claim 1, characterized by, The bottom of the light-removing tower is connected with a tower bottom reboiler; the top of the light-removing tower is connected with an evaporation cooler, the evaporation cooler is connected with a cooler, the cooler is connected to a reflux tank, and the reflux tank is connected to two routes through a light-removing tower reflux pump, one of which is refluxed to the top of the light-removing tower, and the other is connected to the non-aromatic hydrocarbon product tank.
3. The rectification system of cyclopentane according to claim 1 or 2, characterized in that, The bottom of the light-removing tower is provided with a bottom production pump, which is connected to the heavy-removing tower through a feed pressure regulating heat exchanger.
4. The rectification system of cyclopentane according to claim 3, characterized by After being extracted by the bottom production pump, the bottom of the light-removing tower is connected to the feed pressurizing heat exchanger of the light-removing tower to provide heat exchange, and then connected to the heavy-removing tower through the feed pressure regulating heat exchanger.
5. The rectification system of cyclopentane according to claim 1, characterized by, The bottom of the heavy-removing tower is connected with a tower bottom reboiler; the top of the heavy-removing tower is connected with an evaporation cooler, the evaporation cooler is connected with a cooler, the cooler is connected to a reflux tank, and the reflux tank is connected to two routes through a heavy-removing tower reflux pump, one of which is refluxed to the top of the heavy-removing tower, and the other is connected to the cyclopentane product tank; the bottom of the heavy-removing tower is extracted by a bottom production pump.
6. The rectification system of cyclopentane according to claim 1 or 5, characterized in that, A three-dimensional mass transfer tray is used in the heavy-removing tower.
7. The rectification system of cyclopentane according to claim 6, characterized in that, The theoretical tray number of the heavy-removing tower is 80-120, and the opening rate of the tray rising hole is 14%±0.2%.
8. The rectification system of cyclopentane according to claim 1, characterized by, The top of the pre-rectification tower is connected to a cooler and a reflux tank, and two routes are branched from the reflux tank, one of which is refluxed to the top of the pre-rectification tower, and the other is connected to the extractive rectification tower.