CN101696859B - Heat exchanger for distillation - Google Patents
Heat exchanger for distillation Download PDFInfo
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- CN101696859B CN101696859B CN2009101879706A CN200910187970A CN101696859B CN 101696859 B CN101696859 B CN 101696859B CN 2009101879706 A CN2009101879706 A CN 2009101879706A CN 200910187970 A CN200910187970 A CN 200910187970A CN 101696859 B CN101696859 B CN 101696859B
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- tube
- shell
- pass
- heat exchanger
- tube side
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- 238000004821 distillation Methods 0.000 title claims abstract description 13
- 239000000463 material Substances 0.000 claims abstract description 20
- 238000002592 echocardiography Methods 0.000 claims description 3
- 238000002309 gasification Methods 0.000 abstract description 10
- 230000000694 effects Effects 0.000 abstract description 4
- 230000035939 shock Effects 0.000 abstract 1
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 21
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 9
- 239000007788 liquid Substances 0.000 description 9
- 238000010438 heat treatment Methods 0.000 description 8
- 239000012071 phase Substances 0.000 description 8
- 239000007791 liquid phase Substances 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 238000001704 evaporation Methods 0.000 description 4
- 230000008020 evaporation Effects 0.000 description 4
- 229910000856 hastalloy Inorganic materials 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N methanol Natural products OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 150000004075 acetic anhydrides Chemical class 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000005204 segregation Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
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- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention relates to a heat exchanger for distillation. The technical scheme is that: the heat exchanger consists of a shell pass and a tube pass, wherein in the shell pass, an upper cylinder body of the shell pass and a lower cylinder body of the shell pass are connected into one body by an expansion joint, both ends of the shell pass are connected with an upper tube plate and a lower tube plate, a heat exchange tube and a central tube pass a baffle plate, both ends of the heat exchange tube and the central tube are connected with the upper tube plate and the lower tube plate, the central tube is arranged on the axis of the upper tube plate and the lower tube plate, a baffle plate is fixed by a distance tube, a lower cylinder of the shell pass is provided with an exhaust and a steam outlet of the shell pass, an upper cylinder of the shell pass is provided with a steam exhaust and a steam inlet of the shell and a shock proof plate is arranged in the upper cylinder body of the shell pass; and in the tube pass, both ends of a lower tube pass cylinder body are connected with a lower tube pass flat cover and the lower tube plate by flanges, and the lower tube pass is provided witha tube pass exhaust and a material charge port; both ends of an upper tube pass cylinder body are connected with an upper flat cover and the upper tube plate by flanges, and the upper tube pass is provided with a material discharge port and a fixed gas discharge port; and the pads are arranged between the upper tube pass flanges and the upper tube plate and between the lower tube pass flanges andthe lower tube plate. The heat exchanger is high in gasification rate and good in heat exchange effect.
Description
Technical field
The invention relates to a kind of heat exchanger, relates to a kind of aceticanhydride industry particularly, is used for the heat exchanger for distillation on the acetic acid tower of methanol carbonyl synthesized acetic acid.
Background technology
Heat exchanger for distillation be a kind of can heat-shift, gasification space is arranged simultaneously, can make heat up the again a kind of special heat exchanger of gasification of liquid, generally be used on the distillation evaporation equipment.Many and the fractionating column of heat exchanger for distillation share, and mostly is heat exchanger at the bottom of the tower, and material liquid level in heat exchanger and the liquid level in the fractionating column are at sustained height.At the bottom of tower, provide liquid phase to enter into heat exchanger, in evaporation process, material is expanded by heating even gasification in heat exchanger, usually in heat exchanger, there is the liquid phase of 20-25% to be gasified, a part of gas phase in the heat exchanger is discharged from, and the mixing of another part gas phase and liquid phase is sent back in the fractionating column, returns gas, liquid two-phase in the tower, gas phase is upwards by tower tray, and liquid phase can drop at the bottom of the tower.Because the effect of differential static pressure will constantly replenish that part of liquid level that is evaporated at the bottom of the tower, liquid phase enters in the heat exchanger at the bottom of tower once more, through the heat exchange explosive evaporation, constantly circulates and carries out, and constantly carries densely, distills out product.At present, the heat exchanger that many producers adopt mostly is fixed tube-sheet exchanger, floating head heat exchanger or U type heat exchange of heat pipe, and this kind structure rate of gasification is lower, and the internal circulating load of heat exchanger and fractionating column is bigger, the load of segregation section is higher, can not well be used in that methanol carbonyl synthesized acetic acid is technical.
Summary of the invention:
In order to address the above problem, the invention provides a kind of rate of gasification height, good effect of heat exchange, can reach the heat exchanger for distillation of proposing the purity requirement of heating up in a steamer material.
To achieve these goals, the technical scheme that the invention is adopted is: heat exchanger for distillation, form by shell side and tube side two parts;
Described shell side is: shell side upper shell and shell side lower shell are connected as a single entity by expansion joint, the shell side upper shell is connected with upper perforated plate, the shell side lower shell is connected with lower perforated plate, be provided with distance sink tube in the shell side, heat exchanger tube, central tube and deflection plate, heat exchanger tube and central tube pass deflection plate, heat exchanger tube and central tube two ends are connected with lower perforated plate with upper perforated plate respectively, central tube is positioned on the axis of upper perforated plate and lower perforated plate, deflection plate is fixed by distance sink tube, on the shell side lower shell, establish shell side drain and steam (vapor) outlet, establish shell side steam drain and steam inlet on the shell side upper shell, impingement baffle places in the shell side upper shell, and echoes mutually with the position of steam inlet;
Described tube side is: following tube side is: tube side flat cover flange was connected with following flat cover under following tube side cylindrical shell one end passed through, the other end passes through down, and the tube side flange is connected with lower perforated plate, be provided with pad between following tube side flat cover flange and the following flat cover, be provided with pad between following tube side flange and the lower perforated plate; The tube side drain is arranged on down on the flat cover, and material inlet is arranged on down on the tube side cylindrical shell; Last tube side is: go up tube side cylindrical shell one end and be connected with upper flat cover by last tube side flat cover flange, the other end is connected with upper perforated plate by last tube side flange, is provided with pad between last tube side flat cover flange and the upper flat cover, is provided with pad between last tube side flange and the upper perforated plate; Material outlet is arranged on the tube side cylindrical shell, and the fixed gas outlet is located on the upper flat cover;
Heat exchanger tube and central tube communicate with the inner chamber of last tube side cylindrical shell and the inner chamber of following tube side cylindrical shell.
In the invention, the central tube sectional area is 5%~100% of a heat exchanger tube total sectional area.
In the invention, being connected of heat exchanger tube and central tube and upper and lower tube sheet adopt the intensity weldering to add intensity and expand, intensity expands and adopts hydraulic pressure to expand, and should carry out pulling-out force before hydraulic pressure expands and test.
In the invention, heat exchanger tube arranging in shell side is: triangle stringing, corner triangle stringing, square stringing, become a full member square or concentric circles stringing etc.
The key technical indexes such as the table 1 of the invention.
Table 1 distillation heat exchanger the key technical indexes
Shell side | Tube side | |
Maximum working pressure MPa | 1.8 | 0.08(A) |
Design pressure MPa | 2.1 | 0.35/FV |
Operating temperature ℃ | 210/210 | 149/158 |
Design temperature ℃ | 250 | 200 |
Name of material | Middle pressure steam | Aceticanhydride etc. |
Dielectric property | - | Highly harm |
Corrosion allowance mm | 1.5 | 0 |
Hydraulic test pressure MPa | 2.86 | 0.48 |
AB class weld joint efficiency | 0.85 | 0.85 |
The invention, the shell side design pressure is higher, reaches 2.1MPa, the medium aceticanhydride is moderate harm, and therefore, tube side has adopted Hastelloy C-276, this alloy material has superior resistance to corrosion for different chemical environments, is particularly suitable for strong oxidizers such as aceticanhydride.Because the invention temperature difference is bigger, surpass 50 ℃, through practice, add expansion joint.
The beneficial effect of the invention is:
1, adopts the rate of gasification of the invention to reach 25-30%, improved rate of gasification, saved the energy.
2, the invention is simple in structure, and is easily manufactured, and heat-transfer effect is good, handling safety, and total investment expenses are few, the collection heat exchange, separation etc. are multi-functional.
3, its circulation rate can reach about 0.5m/s; Its overall heat-transfer coefficient scope is 580~2900w/ (m2.K).
4, the invention has improved the content of aceticanhydride in the thick product greatly, has reduced the internal circulating load of heat exchanger, has reduced the load of segregation section, can reduce the harshness of technology controlling and process again.
5, in the invention, adopt the intensity weldering to add intensity and expand, intensity expands and adopts hydraulic pressure to expand, and should carry out the pulling-out force test before hydraulic pressure expands, and has prevented the generation of the weld cracking at central tube position.
6, adopt the invention, can reach and propose the purity requirement of heating up in a steamer material.
Description of drawings
Fig. 1 is the structural representation of the invention;
The specific embodiment
As shown in Figure 1, heat exchanger for distillation is made up of shell side and tube side two parts;
Shell side is: shell side upper shell 23 and shell side lower shell 8 are connected as a single entity by expansion joint 24, shell side upper shell 23 is connected with upper perforated plate 19, shell side lower shell 8 is connected with lower perforated plate 5, be provided with some distance sink tubes 7 in the shell side, some heat exchanger tubes 22, central tube 25 and some deflection plates 9, heat exchanger tube 22 and central tube 25 pass deflection plate 9, heat exchanger tube 22 and central tube 25 two ends are connected with lower perforated plate 5 with upper perforated plate 19 respectively, central tube 25 is positioned on the axis of upper perforated plate 19 and lower perforated plate 5, deflection plate 9 is fixing by distance sink tube 7, by pull bar 10 and nut 11 that the deflection plate 9 of the top on the every distance sink tube 7 is fixing, on shell side lower shell 8, establish shell side drain 6 and steam (vapor) outlet 26, on shell side upper shell 23, establish steam drain 12 and steam inlet 20 on the shell side, impingement baffle 21 places in the shell side upper shell 23, and echoes mutually with the position of steam inlet 20;
Tube side is: by tube side and last tube side are formed down; Following tube side is: tube side flat cover flange 3 was connected with following flat cover 2 under following tube side cylindrical shell 4 one ends passed through, the other end passes through down, and tube side flange 28 is connected with lower perforated plate 5, be provided with pad between following tube side flat cover flange 3 and the following flat cover 2, be provided with pad 27 between following tube side flange 28 and the lower perforated plate 5, tube side drain 1 is arranged on down on the flat cover 2, and material inlet 29 is arranged on down on the tube side cylindrical shell 4; Last tube side is: go up tube side cylindrical shell 15 1 ends and be connected with upper flat cover 17 by last tube side flat cover flange 16, the other end is connected with upper perforated plate 19 by last tube side flange 13, be provided with pad between last tube side flat cover flange 16 and the upper flat cover 17, be provided with pad 27 between last tube side flange 13 and the upper perforated plate 19, material outlet 14 is arranged on the tube side cylindrical shell 15, and fixed gas outlet 18 is located on the upper flat cover 17;
The sectional area of central tube is 5%~100% of all heat exchanger tube total sectional areas.In the present embodiment, heat exchanger tube is arranged and is adopted the triangle stringing.
It is bloated that the welding of heat exchanger tube and central tube and upper and lower tube sheet adopts the intensity weldering to add intensity, and intensity expands and adopts hydraulic pressure to expand, and should carry out pulling-out force before hydraulic pressure expands and test.
The material that heat exchanger for distillation adopted: go up tube side flat cover flange 16, following tube side flat cover flange 3, following flat cover 2, upper flat cover 17, following tube side flange 28, last tube side flange 13, the composite that lower perforated plate 5 and upper perforated plate 19 all adopt 16MnII and Hastelloy C-276 to form, last tube side cylindrical shell 15, following tube side cylindrical shell 4, central tube 25 and heat exchanger tube 22 adopt Hastelloy C-276 material, heat exchanger tube should meet the requirement of ASME SB126 standard, central tube should meet the requirement of ASME SB619 standard, the shell side part is except that expansion joint adopts OCr18Ni9, all the other adopt carbon steel structure, and pad adopts Hastelloy C-276+ soft graphite wound gasket.
The operation principle of the invention is:
The trend of fluid: solution such as aceticanhydride are entered down in the tube side cylindrical shell 4 by material inlet 29, rise along the heat exchanger tube inner chamber, enter in the tube side cylindrical shell 15, in uphill process with shell side in medium pressure steam carry out heat exchange, part solution becomes gas phase, part gas phase is never coagulated gas vent 18 and is flowed out, the mixture of part gas phase and liquid phase flows out from material outlet 14, the mixture of some gas phase and liquid phase returns down in the tube side cylindrical shell 4 through central tube, heat recirculation, upwards flow again.Residue is discharged by tube side discharging hole 1, and middle pressure steam enters shell side by steam inlet 20, flows out from steam (vapor) outlet 26 after the deflection plate baffling reduces temperature.
Principle: the shell side inner chamber forms heating clamber by heat exchanger tube and central tube, when heating steam (middle pressure steam) between pipe during the condensation heat release, the heating surface area of the heating surface area of materials such as () aceticanhydrides solution materials such as () aceticanhydrides in the central tube because unit volume solution in the heat exchanger tube, therefore, the relative rate of gasification of solution in the heat exchanger tube (material such as aceticanhydride) is just greater than the rate of gasification of central tube, so the density of the density of the gas-liquid mixture in heat exchanger tube gas-liquid mixture in the central tube.Caused gas-liquid mixture to make progress in heat exchanger tube like this, the Natural Circulation downward at central tube flows.The circulation rate of gas-liquid mixture is relevant with density contrast and pipe range.Density contrast is big more, and heating tube is long more, and circulation rate is big more.Circulating of solution improved the boiling surface heat transfer coefficient, strengthened evaporation process.
Claims (1)
1. heat exchanger for distillation is characterized in that: be made up of shell side and tube side two parts;
Described shell side is: shell side upper shell (23) and shell side lower shell (8) are connected as a single entity by expansion joint (24), shell side upper shell (23) is connected with upper perforated plate (19), shell side lower shell (8) is connected with lower perforated plate (5), be provided with distance sink tube (7) in the shell side, heat exchanger tube (22), central tube (25) and deflection plate (9), heat exchanger tube (22) and central tube (25) pass deflection plate (9), heat exchanger tube (22) and central tube (25) two ends are connected with lower perforated plate (5) with upper perforated plate (19) respectively, central tube (25) is positioned on the axis of upper perforated plate (19) and lower perforated plate (5), deflection plate (9) is fixing by distance sink tube (7), on shell side lower shell (8), establish shell side drain (6) and steam (vapor) outlet (26), on shell side upper shell (23), establish steam drain on the shell side (12) and steam inlet (20), impingement baffle (21) places in the shell side upper shell (23), and echoes mutually with the position of steam inlet (20);
Described tube side is: by tube side and last tube side are formed down; Following tube side is: tube side flat cover flange (3) was connected with following flat cover (2) under following tube side cylindrical shell (4) one ends passed through, the other end passes through down, and tube side flange (28) is connected with lower perforated plate (5), be provided with pad between following tube side flat cover flange (3) and the following flat cover (2), be provided with pad (27) between following tube side flange (28) and the lower perforated plate (5); Tube side drain (1) is arranged on down on the flat cover (2), and material inlet (29) is arranged on down on the tube side cylindrical shell (4); Last tube side is: go up tube side cylindrical shell (15) one ends and be connected with upper flat cover (17) by last tube side flat cover flange (16), the other end is connected with upper perforated plate (19) by last tube side flange (13), be provided with pad between last tube side flat cover flange (16) and the upper flat cover (17), be provided with pad (27) between last tube side flange (13) and the upper perforated plate (19); Material outlet (14) is arranged on the tube side cylindrical shell (15), and fixed gas outlet (18) is located on the upper flat cover (17);
Heat exchanger tube (22) and central tube (25) communicate with the inner chamber of last tube side cylindrical shell (15) and the inner chamber of following tube side cylindrical shell (4).
Priority Applications (1)
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CN2009101879706A CN101696859B (en) | 2009-10-20 | 2009-10-20 | Heat exchanger for distillation |
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CN2009101879706A CN101696859B (en) | 2009-10-20 | 2009-10-20 | Heat exchanger for distillation |
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CN101696859A CN101696859A (en) | 2010-04-21 |
CN101696859B true CN101696859B (en) | 2011-03-30 |
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CN102288051B (en) * | 2011-06-16 | 2012-12-19 | 徐志刚 | Vertical double-tube plate shell-and-tube heat exchanger for evaporating liquid with minimum constant boiling component |
CN102538516A (en) * | 2011-12-31 | 2012-07-04 | 哈尔滨锅炉厂有限责任公司 | Horizontal fixed tube sheet type heat exchanging device and method |
CN103566864B (en) * | 2012-08-06 | 2015-08-19 | 河南省中原大化集团有限责任公司 | A kind of device and method of work improving heat transfer efficiency |
CN102872766B (en) * | 2012-10-21 | 2014-10-22 | 沈阳东方钛业股份有限公司 | Fluoridation reactor of fixed bed |
CN103486883B (en) * | 2013-09-13 | 2016-05-25 | 无锡明燕集团有限公司 | tubular heat exchanger |
CN104830539A (en) * | 2015-05-14 | 2015-08-12 | 南通海珥玛植物油脂有限公司 | Oil treatment system based on molecular distillation device |
CN105335586B (en) * | 2015-12-04 | 2018-04-13 | 山东山大华天软件有限公司 | Method for establishing automatic cloth tube model in design of heat exchanger |
CN110394142A (en) * | 2019-07-26 | 2019-11-01 | 昌和化学新材料(江苏)有限公司 | An a kind of benzene reaction kettle of the esterification condenser |
CN113280657A (en) * | 2021-06-24 | 2021-08-20 | 江苏盛泰化学科技有限公司 | Three-phase heat exchanger |
CN113716443A (en) * | 2021-08-18 | 2021-11-30 | 安徽弘徽科技有限公司 | Clamping structure-based double-material-barrel hoisting device and method |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4632182A (en) * | 1982-11-19 | 1986-12-30 | Motoren- Und Turbinen-Union Munchen Gmbh | Heat exchanger for gases of greatly different temperatures |
CN201524439U (en) * | 2009-10-20 | 2010-07-14 | 沈阳东方钛业有限公司 | Heat exchanger for distillation |
-
2009
- 2009-10-20 CN CN2009101879706A patent/CN101696859B/en active Active
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4632182A (en) * | 1982-11-19 | 1986-12-30 | Motoren- Und Turbinen-Union Munchen Gmbh | Heat exchanger for gases of greatly different temperatures |
CN201524439U (en) * | 2009-10-20 | 2010-07-14 | 沈阳东方钛业有限公司 | Heat exchanger for distillation |
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CN101696859A (en) | 2010-04-21 |
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Address after: 110000 Liaoning Province, Shenyang Hunnan New District Nanping Road No. 2 Patentee after: Shenyang Orient Titanium Industry Co., Ltd. Address before: South Street in Dongling District of Shenyang city of Liaoning Province, No. 137 110016 Patentee before: Shenyang Orient Titanium Industry Co., Ltd. |