CN106380393A - Method for recovering acetic acid from low-concentration acetic acid wastewater by heat pump and multi-effect distillation - Google Patents
Method for recovering acetic acid from low-concentration acetic acid wastewater by heat pump and multi-effect distillation Download PDFInfo
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- CN106380393A CN106380393A CN201610783238.5A CN201610783238A CN106380393A CN 106380393 A CN106380393 A CN 106380393A CN 201610783238 A CN201610783238 A CN 201610783238A CN 106380393 A CN106380393 A CN 106380393A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
- C07C51/44—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation by distillation
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/52—Heat recovery pumps, i.e. heat pump based systems or units able to transfer the thermal energy from one area of the premises or part of the facilities to a different one, improving the overall efficiency
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
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- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a method for recovering acetic acid from low-concentration acetic acid wastewater by heat pump and multi-effect distillation and belongs to the field of acetic acid recovery technology. According to the invention, acetic acid is recovered by heat pump and multi-effect distillation combined system. After steam at the tower top of a heat pump tower is compressed, the compressed steam not only can be used as heat for the tower bottom of the heat pump tower and also can be used for preheating acetic acid-containing wastewater and can be used as a heat source for the next rectifying tower's reboiler. Energy consumption of the system is much lower than energy consumption of a single multi-effect distillation system. In addition, the method of the invention is suitable for recovering of acetic acid in low-concentration acetic acid wastewater. Purity of acetic acid obtained is high, and recovery rate is also high. Meanwhile, there is no need of adding other solvents for the recovery of acetic acid. The technology is simple and will not bring pollution of other substances. The method for recovering acetic acid from low-concentration acetic acid wastewater has advantages of simple operation, low cost, low energy consumption and high purity and high recovery rate of acetic acid.
Description
Technical field
The invention belongs to acetic acid recovery technical field, specially a kind of heat pump-multi-effect distillation is from low-concentration acetic acid wastewater
The method of recovery of acetic acid.
Background technology
Acetic acid is a kind of important conventional industrial chemicals or product, and many chemical processes all refer to the utilization of acetic acid and return
Receive.It is to adopt conventional distillation method separation water-vinegar stock with recovery of acetic acid earliest, the column plate that this method needs is many, and reflux ratio is big,
The response rate is low, high energy consumption；Oldest power-economizing method be plus acetate or the physical property material close with acetic acid to carry out azeotropic smart
Evaporate, the more difficult grasp of its operating condition, and still contain entrainer and a small amount of acetic acid in the water after separation, need recycling, energy-conservation
Amplitude little.In recent years, some researcheres have been carried out with the method separation water of liquid-liquid extraction rectification and the research of acetic acid, profit
Be significantly higher than acetic acid with a kind of immiscible with water and boiling point and have the solvent of strong affinity with acetic acid, such as dimethylformamide,
N- methylacetamide, N- N-formyl morpholine N, sulfolane, AEOA etc., acetic acid is transferred in the solvent of addition from water, then
Using rectificating method by solvent and acetic acid separated, reach the purpose of extract and separate water-acetic acid, this method is because selected solvent is in water
There is certain dissolubility, often bring the pollution of the third material.
Content of the invention
It is an object of the invention to provide a kind of heat pump-multi-effect distillation system recovery of acetic acid from low-concentration acetic acid wastewater
Method, the present invention, while ensureing to obtain high-purity acetic acid, also can substantially reduce energy consumption.
The technical solution adopted for the present invention to solve the technical problems is：A kind of heat pump-multi-effect distillation is from low-concentration acetic acid
The method of recovery of acetic acid in waste water, using heat pump-multi-effect distillation combined system recovery of acetic acid.
A kind of preferred as the present invention, described heat pump-multi-effect distillation combined system is made up of heat pump tower and purifying column, heat
A pump column overhead steam part is used for purifying column reboiler heat supply, and another part supplies to heat pump tower reboiler after compressor compression
Heat, then return heat pump column overhead to after spirit of vinegar feeding preheating, after the purified tower rectification of heat pump tower materials at bottom of tower, bottom of towe obtains vinegar
Acid product.
A kind of preferred as the present invention, described heat pump-multi-effect distillation combined system is made up of heat pump tower and purifying column, heat
Pump column overhead steam all after compressor compression, first to heat pump tower reboiler heat supply, then to spirit of vinegar feeding preheating, the most backward
Purifying column reboiler heat supply, after the purified tower rectification of heat pump tower materials at bottom of tower, bottom of towe obtains acetate products.
One kind as the present invention is preferred, and described heat pump tower and purifying column are selected from the compression rectification tower of different pressures, normal pressure
Rectifying column and vacuum rectification tower.
A kind of preferred as the present invention, described heat pump tower can be packed tower or plate column, preferably more warp
The plate column of Ji.Described purifying column can be packed tower or plate column, preferably packed tower.
A kind of preferred as the present invention, the theoretical cam curve of described heat pump tower is 15-120, and reflux ratio is 1.0-7.0,
Pressure is 0.10-0.50MPa.
A kind of preferred as the present invention, the theoretical cam curve of described purifying column is 15-120, and reflux ratio is 1.0-7.0,
Pressure is 0.01-0.06MPa.Further, when heat pump pressure tower is more than 0.3MPa, purifying column is atmospheric distillation tower.
The principle of heat pump distillation is：Heat pump column overhead steam is all compressed through compressor, and provides heat to reboiler,
Only need a tower it is no longer necessary to outside provide steam heating, be equivalent to infinitely multistage multi-effect distillation.If compressed steam is used for
As the thermal source of next rectifying column reboiler, it is the formation of the rectification mode of heat pump-multi-effect distillation combined system.So, exist
In whole flow process, need to heat in addition to steam when driving, the enough heat pumps of heat after compressor compression for the heat pump column overhead steam
Tower and purifying column reboiler heat supply, whole distillation process is no longer necessary to external steam, and energy consumption substantially reduces.Because flow process is short, make
Equipment investment low, device is simple to operate.Certainly, if also containing other impurity in raw material, can according to circumstances increase in other towers
Plus cooling medium etc..
In distillation process, the separating power of rectifying column, depend primarily on the suitable number of theoretical plate of rectifying column and backflow
The size of ratio.The size of reflux ratio, the separating effect to distillation process and economy important.Increase reflux ratio, just
Product purity can be improved, but also increase energy consumption.Therefore, in distillation design, reflux ratio is a parameter that need to conscientiously select.
Beneficial effects of the present invention：The present invention adopts heat pump-multi-effect distillation combined system recovery of acetic acid, and heat pump column overhead is steamed
Vapour after compression, can be used not only as heat pump tower bottom of towe heat moreover it is possible to preheat to waste water, and as purifying column reboiler
Thermal source is lower with respect to single multi-effect distillation system energy consumption.Additionally, the inventive method vinegar be applied to low-concentration acetic acid wastewater
The recovery of acid, the acetic acid purity of gained is high, and the response rate is also high.Meanwhile, recovery of acetic acid is not required to add other solvents, process is simple,
The pollution of other materials will not be brought.
Brief description
Fig. 1 is the quadruple effect distillation process figure of the embodiment of the present invention 1；
Fig. 2 is the heat pump-multi-effect distillation combination distillation process figure of the embodiment of the present invention 2；
Fig. 3 is the heat pump-multi-effect distillation combination distillation process figure of embodiment of the present invention 3-5.
Reference：1- preheater, 2- compressor, 3- reboiler, 4- condenser, 5- vacuum pump, 6- compression rectification tower, 7-
Atmospheric distillation tower, 8- vacuum rectification tower.
Specific embodiment
In order that the objects, technical solutions and advantages of the present invention become more apparent, below in conjunction with drawings and Examples, right
The present invention is further elaborated.All features disclosed in this specification, or disclosed all methods or during
Step, in addition to mutually exclusive feature and/or step, all can combine by any way.
Any feature disclosed in this specification (including any accessory claim, summary), unless specifically stated otherwise,
Replaced by other alternative features equivalent or that there is similar purpose.I.e., unless specifically stated otherwise, each feature is a series of
One of equivalent or similar characteristics example.
Embodiment 1：
The present embodiment is quadruple effect rectification, as the comparative example of embodiment 2～5, using quadruple effect disclosed in patent CN1919821
The method of rectification recovery of acetic acid from low-concentration acetic acid wastewater, idiographic flow is as shown in Figure 1.Four towers be respectively No. 1 tower, No. 2
Tower, No. 3 towers and No. 4 towers.No. 1 tower and No. 2 towers are compression rectification tower, and No. 2 tower pressure interior forces are less than No. 1 tower pressure interior force, and No. 3 towers are
Atmospheric distillation tower, No. 4 towers are vacuum rectification tower；Four towers are ripple packing, and number of theoretical plate is 52.
Each tower operating condition see table：
| Equipment | Tower top pressure MPa (a) | Reflux ratio | Tower top temperature (DEG C) | Bottom temperature (DEG C) |
| No. 1 tower | 0.430 | 3.20 | 111.8 | 112.3 |
| No. 2 towers | 0.153 | 3.13 | 99.0 | 99.7 |
| No. 3 towers | 0.099 | 3.27 | 84.9 | 86.0 |
| No. 4 towers | 0.059 | 3.24 | 64.1 | 74.2 |
Material balance see table：
Consumption of calorie is 5643.13kW to the present embodiment method per hour, and recovery rate is 99.15%.(" former in table
Material " refers to the waste water raw material before recovery of acetic acid, and " product " refers to the high-purity acetic acid of gained after rectifying column recovery,
" waste water " refers to remaining aqueous solution after recovery of acetic acid；Pressure is absolute pressure, similarly hereinafter.)
Embodiment 2
The present embodiment be combination rectification, using the inventive method heat pump-multi-effect distillation combined system method from low concentration
Recovery of acetic acid in acetic acid wastewater, flow process is shown in Fig. 2, and two towers are respectively No. 1 tower, No. 2 towers.No. 1 tower is compression rectification tower, No. 2 towers
For vacuum rectification tower；No. 1 tower is plate column, and number of theoretical plate is 72, No. 2 towers is ripple packing, and number of theoretical plate is 52.
Each tower operating condition see table：
Material balance see table：
The present embodiment heat pump column overhead steam part is used for purifying column reboiler 3 heat supply, and another part is pressed through compressor 2
Give heat pump tower reboiler 3 heat supply after contracting, then return heat pump column overhead to after spirit of vinegar feeding preheating, heat pump tower materials at bottom of tower is through carrying
After pure tower rectification, bottom of towe obtains acetate products.
The present embodiment method consumes energy for 1379.86kW (compressor efficiency 80%, similarly hereinafter) per hour, compared with Example 1,
Energy efficient 75.55%；Recovery rate is 99.59%.
Embodiment 3
The present embodiment be combination rectification, using the inventive method heat pump-multi-effect distillation combined system method from low concentration
Recovery of acetic acid in acetic acid wastewater, flow process is shown in Fig. 3, and two towers are respectively No. 1 tower, No. 2 towers.No. 1 tower is compression rectification tower, No. 2 towers
For vacuum rectification tower；No. 1 tower is plate column, and number of theoretical plate is 102, No. 2 towers is ripple packing, and number of theoretical plate is 62.
Each tower operating condition see table：
| Equipment | Tower top pressure MPa (a) | Reflux ratio | Tower top temperature (DEG C) | Bottom temperature (DEG C) |
| No. 1 tower | 0.120 | 2.85 | 104.8 | 111.0 |
| No. 2 towers | 0.025 | 1.80 | 65.3 | 78.2 |
Material balance see table：
The present embodiment heat pump column overhead steam is all after compressor 2 compression, first to heat pump tower reboiler 3 heat supply more right
Spirit of vinegar feeding preheating, the most backward purifying column reboiler 3 heat supply, after the purified tower rectification of heat pump tower materials at bottom of tower, bottom of towe obtains
Acetate products.
The present embodiment method consumes energy per hour for 1205.72kW, compared with Example 1, energy efficient 78.63%；Acetic acid
The response rate is 99.60%.
Embodiment 4
The present embodiment be combination rectification, using the inventive method heat pump-multi-effect distillation combined system method from low concentration
Recovery of acetic acid in acetic acid wastewater, flow process is shown in Fig. 3, and two towers are respectively No. 1 tower, No. 2 towers.No. 1 tower is compression rectification tower, No. 2 towers
For vacuum rectification tower；No. 1 tower is plate column, and number of theoretical plate is 102, No. 2 towers is ripple packing, and number of theoretical plate is 62.
Each tower operating condition see table：
| Equipment | Tower top pressure MPa (a) | Reflux ratio | Tower top temperature (DEG C) | Bottom temperature (DEG C) |
| No. 1 tower | 0.200 | 3.30 | 120.2 | 125.1 |
| No. 2 towers | 0.025 | 1.80 | 65.3 | 78.2 |
Material balance see table：
The present embodiment heat pump column overhead steam is all after compressor 2 compression, first to heat pump tower reboiler 3 heat supply more right
Spirit of vinegar feeding preheating, the most backward purifying column reboiler 3 heat supply, after the purified tower rectification of heat pump tower materials at bottom of tower, bottom of towe obtains
Acetate products.
The present embodiment method consumes energy per hour for 1151.99kW, compared with Example 1, energy efficient 79.59%；Acetic acid
The response rate is 99.59%.
Embodiment 5
The present embodiment be combination rectification, using the inventive method heat pump-multi-effect distillation combined system method from low concentration
Recovery of acetic acid in acetic acid wastewater, flow process is shown in Fig. 3, and two towers are respectively No. 1 tower, No. 2 towers.No. 1 tower is compression rectification tower (heat pump
Tower), No. 2 towers are vacuum rectification tower；No. 1 tower is plate column, and number of theoretical plate is 102, No. 2 towers is ripple packing, and number of theoretical plate is
62.
Each tower operating condition see table：
| Equipment | Tower top pressure MPa (a) | Reflux ratio | Tower top temperature (DEG C) | Bottom temperature (DEG C) |
| No. 1 tower | 0.300 | 3.70 | 133.5 | 137.7 |
| No. 2 towers | 0.025 | 1.90 | 65.2 | 78.6 |
Material balance see table：
The present embodiment heat pump column overhead steam is all after compressor 2 compression, first to heat pump tower reboiler 3 heat supply more right
Spirit of vinegar feeding preheating, the most backward purifying column reboiler 3 heat supply, after the purified tower rectification of heat pump tower materials at bottom of tower, bottom of towe obtains
Acetate products.
The present embodiment method consumes energy per hour for 1137.63kW, compared with Example 1, energy efficient 79.84%；Acetic acid
The response rate is 99.76%.
The foregoing is only presently preferred embodiments of the present invention, not in order to limit the present invention, all essences in the present invention
Any modification, equivalent and improvement made within god and principle etc., should be included within the scope of the present invention.
Claims (8)
1. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater is it is characterised in that methods described is adopted
With heat pump-multi-effect distillation combined system recovery of acetic acid.
2. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater as claimed in claim 1, its feature
It is, described heat pump-multi-effect distillation combined system is made up of heat pump tower and purifying column, a heat pump column overhead steam part is used for carrying
Pure tower reboiler heat supply, another part through compressor compression after give heat pump tower reboiler heat supply, then to spirit of vinegar feeding preheating after
Return heat pump column overhead, after the purified tower rectification of heat pump tower materials at bottom of tower, bottom of towe obtains acetate products.
3. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater as claimed in claim 1, its feature
It is, described heat pump-multi-effect distillation combined system is made up of heat pump tower and purifying column, heat pump column overhead steam is all through compressor
After compression, first to heat pump tower reboiler heat supply, then to spirit of vinegar feeding preheating, the most backward purifying column reboiler heat supply, heat pump tower
After materials at bottom of tower purified tower rectification, bottom of towe obtains acetate products.
4. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater as described in Claims 2 or 3, its
It is characterised by, described heat pump tower and purifying column are selected from compression rectification tower, atmospheric distillation tower and the vacuum rectification tower of different pressures.
5. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater as described in Claims 2 or 3, its
It is characterised by, described heat pump tower is packed tower or plate column, described purifying column is packed tower or plate column.
6. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater as described in Claims 2 or 3, its
It is characterised by, the theoretical cam curve of described heat pump tower is 15-120, and reflux ratio is 1.0-7.0, and pressure is 0.10-0.50MPa.
7. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater as described in Claims 2 or 3, its
It is characterised by, the theoretical cam curve of described purifying column is 15-120, and reflux ratio is 1.0-7.0, and pressure is 0.01-0.06MPa.
8. a kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater as claimed in claim 7, its feature
It is, when heat pump pressure tower is more than 0.3MPa, purifying column is atmospheric distillation tower.
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| CN201610783238.5A CN106380393B (en) | 2016-08-30 | 2016-08-30 | A kind of method of heat pump-multi-effect distillation recovery of acetic acid from low-concentration acetic acid wastewater |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1919821A (en) * | 2006-09-13 | 2007-02-28 | 西南化工研究设计院 | Method of recovery acetic acid from acetic acid containing waste water |
| US20070102276A1 (en) * | 2005-11-09 | 2007-05-10 | Honeywell International, Inc. | Apparatus and methods for water regeneration from waste |
| CN102153092A (en) * | 2011-04-27 | 2011-08-17 | 天津大学 | Heat pump distillation and multi-effect distillation integrated device and process for purifying trichlorosilane |
-
2016
- 2016-08-30 CN CN201610783238.5A patent/CN106380393B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070102276A1 (en) * | 2005-11-09 | 2007-05-10 | Honeywell International, Inc. | Apparatus and methods for water regeneration from waste |
| CN1919821A (en) * | 2006-09-13 | 2007-02-28 | 西南化工研究设计院 | Method of recovery acetic acid from acetic acid containing waste water |
| CN102153092A (en) * | 2011-04-27 | 2011-08-17 | 天津大学 | Heat pump distillation and multi-effect distillation integrated device and process for purifying trichlorosilane |
Non-Patent Citations (1)
| Title |
|---|
| 孙钦鹤等: "低浓度DMF废水的热集成回收新工艺", 《计算机与应用化学》 * |
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