CN101961633B - Unsym-trimethyl benzene continuous oxidation reaction equipment - Google Patents
Unsym-trimethyl benzene continuous oxidation reaction equipment Download PDFInfo
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- CN101961633B CN101961633B CN2010105095601A CN201010509560A CN101961633B CN 101961633 B CN101961633 B CN 101961633B CN 2010105095601 A CN2010105095601 A CN 2010105095601A CN 201010509560 A CN201010509560 A CN 201010509560A CN 101961633 B CN101961633 B CN 101961633B
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Abstract
The invention relates to unsym-trimethyl benzene continuous oxidation reaction equipment, which belongs to the technical field of chemical production equipment. The equipment comprises a tower-tank reactor kettle body, wherein the upper section of the kettle body is provided with a stirring device, while the top is provided with a gas-phase outlet; the lower section of the kettle body is provided with a heating device, while the bottom is provided with a discharge hole; the kettle body is at least provided with two stages of feed pipes distributed one above the other; a first-stage feed pipe is positioned on the upper section of the kettle body; a first-stage air inlet pipe is arranged below the first-stage feed pipe; a second-stage feed pipe is positioned below the first-stage air inlet pipe; and a second-stage air inlet pipe is arranged below the second-stage feed pipe. The reaction equipment of the invention has the advantages of completely solving the problems such as wall accretion, blockage and the like of a solid material caused by the adoption of a conveying pipe and increasing the yield of unsym-trimethyl benzene, along with simple and convenient process and economic equipment investment; and a baffle plate and a guide cylinder arranged on the equipment have the effects of increasing oxidation efficiency, so that the final yield of the unsym-trimethyl benzene is up to about 95 percent due to the adoption of the equipment.
Description
Technical field
The present invention relates to a kind of pseudocumene continuous oxidation reaction equipment, the continuous oxidation technology of especially a kind of pseudocumene is produced the oxidation reaction apparatus of trimellitic acid, belongs to the chemical production equipment technical field.
Background technology
Trimellitic acid is a kind of important chemical material.Understand according to the applicant, the method that existing pseudocumene generates trimellitic acid through oxidation reaction has two kinds of batch (-type) and continous ways.
The oxidation reaction apparatus that clearance-type adopts is generally the tower bubbling style reactor.This type of reactor is introduced air from the bottom of tower, flow out from the top.Air produces oxidation reaction with reaction mass through contacting naturally.1), air and reaction mass mix inhomogeneous its defective has:; The air molecule surface touches material can produce oxidation reaction; Do not reach and then form bubble and scurry from reactor head and flow out, so reaction efficiency is not high, only is suitable for low-producing small-bore tower reactor; 2), every at a distance from needs repetition charging in several hours, blowing, intensifications of boosting, step-down cooling, so the hardware of equipment is prone to produce tired, service life is short, the frequency of maintenance height, safety coefficient is not high, environmental protection pressure is big; 3), energy consumption is high, loss of material is big, energy is difficult to recycle.
The oxidation reaction apparatus that continous way adopts is with many reactors (oxidation reactors of a plurality of clearance-types) series connection, and classification is oxidation progressively, makes pseudocumene be oxidized to trimellitic acid continuously.Its typical structure can be 200610086124.1 one Chinese patent application referring to application number.This kind equipment significant disadvantages is that equipment investment is big, and technological process is long.Especially, the connection between each reactor need increase pipeline or conveying equipment, thereby causes problems such as solid material knot wall, obstruction easily, makes to be difficult to long-time normal operation; In addition, the operation of many reactors control is comparatively complicated, and technic index is difficult to stable control, directly influences constant product quality.
Summary of the invention
The objective of the invention is to: the shortcoming to above-mentioned prior art exists proposes a kind of integrated pseudocumene continuous oxidation reaction of integrated form equipment with higher yields, thereby makes process route simple and direct, constant product quality.
In order to reach above purpose, the basic technical scheme of pseudocumene continuous oxidation reaction equipment of the present invention is: comprise tower jar shape reactor kettle; The epimere of said kettle is equipped with agitating device, and the top has gaseous phase outlet; The hypomere of said kettle has heater, and the bottom has discharging opening; Said kettle has upper and lower distribution secondary feed tube at least; First order feed pipe is positioned at said kettle epimere, and first order air inlet pipe is equipped with in its below; Second level feed pipe is positioned under the first order air inlet pipe, and second level air inlet pipe is equipped with in its below.
The applicant learns through repetition test in practice; The reaction rule that the pseudocumene oxidation generates trimellitic acid is a curve that descends gradually; Concentration raising along with trimellitic acid; Reaction speed can be slowed down gradually, and after the trimellitic acid of pseudocumene oxidation reaction generation reaches certain saturated concentration, further oxidation reaction will be very difficult.Therefore on the existing equipment basis, even take such as stirring, rationally control conventional measures such as mixing ratio, reaction temperature and interpolation catalyst, the yield of final trimellitic acid is difficult to surpass 80% usually.Above-mentioned basic technical scheme of the present invention adopts the multilevel hierarchy charging, and the reaction substep that makes pseudocumene be oxidized to trimellitic acid carries out step by step, and the trimellitic acid content that generates when first order reaction is when being tending towards the carrying out of saturated inhibitory reaction; The next stage feed arrangement will be imported new reaction mass; And the required air of corresponding input, list can continue oxidation because reactant liquor obtains dilution, and owing to add input new reaction mass and air; Make original reaction speed get a promotion; The lifting variation has appearred in response curve, makes remaining pseudocumene be able to continue to be converted into trimellitic acid, thereby has effectively improved the yield of trimellitic acid.
The present invention further improves, and separated between the upper and lower, the circuitous deflection plate that distributes is housed in the kettle between said second level feed pipe and the second level air inlet pipe, has cellular passage on the said deflection plate.Like this, when reacting in the second level, reaction mass from top to bottom drops on the deflection plate, then flow through the from the bottom to top passage of deflection plate of air, and the bearing reaction material is the boiling shape, fully mixes contacting with air, thereby has further improved oxidation efficiency.
Further perfect of the present invention be, said kettle hypomere has third level air inlet pipe, and said kettle hypomere is equipped with guide shell on third level air inlet pipe, and the venthole of said third level air inlet pipe is positioned at the lower port scope of said guide shell.Like this; Terminal stage in reaction; Further the air of input has not only guaranteed sufficient amount of oxygen; And by guide shell, the reaction mass that causes to fall and break receives the impact of ascending air and the ring-type that travels back across between kettle hypomere and the guide shell falls at interval, thereby further oxidation in dynamic turbulent process.
Facts have proved; After consersion unit of the present invention has been taked hierarchy; Not only make process route simple and direct because of equipment is integrated, equipment investment economy, the solid material of thoroughly having avoided adopting conveyance conduit to cause is tied problems such as wall, obstruction; And improved the trimellitic acid yield, therefore had significant substantive distinguishing features and outstanding progress.The deflection plate of setting up on this basis, guide shell then all have the effect that improves oxidation efficiency, adopt the final trimellitic acid yield of the present invention can reach 95% thereby make.
Description of drawings
Below in conjunction with accompanying drawing the present invention is further described.
Fig. 1 is the structural representation of one embodiment of the invention.
Fig. 2 is the vertical view of Fig. 1.
Fig. 3 is the structural representation of Fig. 1 embodiment deflection plate part.
Fig. 4 is the vertical view of Fig. 3 deflection plate.
Fig. 5 is the structural representation of Fig. 1 embodiment guide shell part.
Fig. 6 is Fig. 1 embodiment heating arrangement sketch map.
The specific embodiment
Embodiment one
The pseudocumene continuous oxidation reaction equipment of present embodiment is as depicted in figs. 1 and 2, and the reactor kettle 1 of tower jar shape is divided into the three sections 1-1 in upper, middle and lower, 1-2, the 1-3 that reduces from top to bottom, connects through the transition awl between each section.The epimere of kettle is equipped with the agitating device 4 of external vertical driven by motor, and the top has gaseous phase outlet V, and measurement, venting.The hypomere 1-3 of kettle and stage casing 1-2 have double wall formula hot oil heater 5 (its concrete structure hereinafter combines Fig. 6 to detail), and the bottom has discharging opening D, and heat conductive oil inlet H1 and temperature-measuring port T1.Kettle has upper and lower distribution secondary feed tube.First order feed pipe is positioned at the kettle epimere, and by charging aperture A1 input, the first order air inlet pipe by air intlet G1 input is equipped with in its below.On the vertical axle of agitating device sencond stage impeller spaced apart is housed, this sencond stage impeller lays respectively at the above and below of first order feed pipe.Second level feed pipe is positioned at the kettle stage casing under the first order air inlet pipe, and by charging aperture A2 input, the second level air inlet pipe by air intlet G2 input is equipped with in its below.Upper and lower interval, the circuitous level Four deflection plate 2 that distributes (its concrete structure hereinafter combines Fig. 3, Fig. 4 to detail) are housed in the kettle stage casing between second level feed pipe and the second level air inlet pipe.Kettle hypomere adjacent bottom place has the third level air inlet pipe by air intlet G3 input, and guide shell 3 (its concrete structure hereinafter combines Fig. 5 to detail) is housed on third level air inlet pipe.Feed pipes at different levels and air inlet pipe are concentric ring-shaped or the snail shape all can; Spaced apart portalling comparatively is evenly distributed on feed pipe or the interior cross section of the residing kettle of air inlet pipe on feed pipe and the air inlet pipe thereby make, and the venthole of third level air inlet pipe all is positioned at the lower port scope of guide shell 3.
The concrete structure of deflection plate 2 such as Fig. 3, shown in Figure 4; One side is the liquid storage pool 2-1 that forms with the kettle adjacent sidewalls, and opposite side is vertical drainage plate 2-2, is the sieve plate 2-3 with cellular passage between liquid storage pool and the drainage plate; The top edge of drainage plate is higher than the sieve plate upper surface; Thereby form the overflow rib, its lower limb extends in the liquid storage pool of next stage deflection plate, and forms the baffling gap with the inner edge of this liquid storage pool.Level Four deflection plate 2 is upper and lower interval, the circuitous distribution in the kettle stage casing.When reaction mass drops on the deflection plate from top to bottom; And air is flowed through from the bottom to top during the passage of deflection plate; Reaction mass is blowed floating is the boiling shape, liquid pseudocumene reaction mass by overflow on liquid storage pool and the sieve plate after, flow into the liquid storage pool of next stage deflection plate along drainage plate; Can keep the passage at kettle middle part like this is the ascending air passage; Reaction mass then need pass through full of twists and turns baffling passage, thereby guaranteeing further that reaction mass fully mixes with air contacts, and improves oxidation efficiency.
Double wall formula hot oil heater concrete structure is as shown in Figure 6, and the hypomere 1-3 and the stage casing 1-2 of kettle have overcoat separately respectively, thereby the first order under being formed in heats double wall 5-1 and heats double wall 5-2 in the last second level.The conduction oil of first order heating double wall is got into by the H1 mouth, is exported by H2; The conduction oil of second level heating double wall is got into by the H3 mouth, is exported by H4.Like this, the temperature in the segmentation control reactor makes it reach perfect condition as required.In addition, have helical baffle in the heating double walls at different levels, thereby form the spiral upper upstream road, so that guarantee that temperature is even.
In addition, the deflection plate of the kettle stage casing the superiors of present embodiment top is provided with by adding mouthful first order catalyst make-up pipe of B1 input, and the guide shell top of kettle hypomere is provided with by adding mouthful second level catalyst make-up pipe of B2 input.Thereby can add catalyst by the reaction needed classification easily.Also be provided with refluxing opening F at the kettle epimere, can the catalyst after the vaporization that heat up be drawn after condensation process Returning reactor by gaseous phase outlet.All the other via holes also have the M1-4 manhole among the figure, N1-3 tail oxygen hole, T1-6 thermometer hole.
Facts have proved that behind the equipment of employing embodiment, material is realized fractional order reaction in a reactor, fully oxidation, the trimellitic acid yield can reach 95%, has following remarkable action effect
1, adopts the multilevel hierarchy charging, efficiently solve the problem that trimellitic acid too high levels inhibitory reaction carries out, improve oxidation efficiency, make pseudocumene meet its multistep gradual reaction mechanism as far as possible, be converted into trimellitic acid to greatest extent.
2, adopt classification to add catalyst, satisfied different demands, be convenient to adjust the content of each stage catalyst, reach the effect of dynamic control peak optimization reaction speed at stage of reaction catalyst at different levels.
3, adopt multistage air inlet to distribute, adapt to the progressively oxidizing process that pseudocumene changes into trimellitic acid, satisfy the different demands of oxidations at different levels, can improve the conversion ratio of oxidation reaction through the oxygen demand of control step reactions at different levels to oxygen content.
4, inside reactor is provided with multistage distribution of gas agitating device, stirs through many places, make interior each section gas-liquid contact-making surface of reactor reach maximization, thereby it is more complete to make that oxidation reaction is carried out.
5, inside reactor is provided with guide shell preventing materials accumulation facility, and material is rolled in the reactor bottom circulation, avoids the buildup clogging, the life cycle of extension reactor.
6, adopt multistage heating; Can import the heat medium of different temperatures as required; Thereby satisfy the demand that pseudocumene is oxidized to the different heats of each order reaction of trimellitic acid; Effectively inner each the regional temperature of control and conditioned reaction device avoids the material over oxidation to generate carbon dioxide and carbon monoxide, improves oxidization-hydrogenation ratio.
7, at inside reactor the multiple spot detection system is set,, the operation control optimization of W-response equipment is laid a good foundation for realizing Computerized intelligent control.
In a word, present embodiment uses separate unit integrated reacting equipment, has reduced equipment investment, has shortened technological process; Simplify technology controlling and process, improved oxidation efficiency, guaranteed product quality; Can avoid the buildup blockage problem, the extension reactor cycle of operation, and can reclaim residual heat of reaction.
Except that the foregoing description, the present invention can also have other embodiments.For example, the kettle hypomere also can be provided with feed pipe, perhaps the more multistage feed pipe of kettle setting; Kettle has only upper and lower two sections, saves the deflection plate in stage casing, and perhaps deflection plate is arranged on hypomere and without guide shell; Can not establish partition structure between each of kettle section, and only be that relative position is distinguished; Or the like.All employings are equal to the technical scheme of replacement or equivalent transformation formation, all drop on the protection domain of requirement of the present invention.
Claims (10)
1. a pseudocumene continuous oxidation reaction equipment comprises tower jar shape reactor kettle; The epimere of said kettle is equipped with agitating device, and the top has gaseous phase outlet; The hypomere of said kettle has heater, and the bottom has discharging opening; It is characterized in that: said kettle has upper and lower distribution secondary feed tube at least; First order feed pipe is positioned at the epimere of said kettle, and first order air inlet pipe is equipped with in its below; Second level feed pipe is positioned under the first order air inlet pipe, and second level air inlet pipe is equipped with in its below.
2. pseudocumene continuous oxidation reaction equipment according to claim 1; It is characterized in that: separated between the upper and lower, the circuitous deflection plate that distributes is housed in the kettle between said second level feed pipe and the second level air inlet pipe, has cellular passage on the said deflection plate.
3. pseudocumene continuous oxidation reaction equipment according to claim 2; It is characterized in that: said kettle hypomere has third level air inlet pipe; Said kettle hypomere is equipped with guide shell on third level air inlet pipe, the venthole of said third level air inlet pipe is positioned at the lower port scope of said guide shell.
4. according to claim 2 or 3 described pseudocumene continuous oxidation reaction equipment, it is characterized in that: said reactor kettle is divided into three sections of the upper, middle and lower of reducing from top to bottom, connects through the transition awl between each section.
5. pseudocumene continuous oxidation reaction equipment according to claim 4 is characterized in that: a side of said deflection plate is the liquid storage pool that forms with the kettle adjacent sidewalls, and opposite side is vertical drainage plate; It between said liquid storage pool and the drainage plate sieve plate with cellular passage; The top edge of said drainage plate is higher than the sieve plate upper surface, forms the overflow rib; The lower limb of said drainage plate extends in the liquid storage pool of next stage deflection plate, and forms the baffling gap with the inner edge of this liquid storage pool.
6. pseudocumene continuous oxidation reaction equipment according to claim 5; It is characterized in that: said heater is a double wall formula hot oil heater; Comprise the first order heating double wall that kettle hypomere and overcoat constitute, and the second level heating double wall of kettle stage casing and overcoat formation.
7. pseudocumene continuous oxidation reaction equipment according to claim 6 is characterized in that: have helical baffle in the said heating double walls at different levels, form the spiral upper upstream road.
8. pseudocumene continuous oxidation reaction equipment according to claim 7 is characterized in that: the deflection plate top of the said kettle stage casing the superiors is provided with first order catalyst make-up pipe, and the guide shell top of said kettle hypomere is provided with second level catalyst make-up pipe.
9. pseudocumene continuous oxidation reaction equipment according to claim 8 is characterized in that: on the vertical axle of said agitating device sencond stage impeller spaced apart is housed, said sencond stage impeller lays respectively at the above and below of first order feed pipe.
10. pseudocumene continuous oxidation reaction equipment according to claim 9 is characterized in that: said feed pipes at different levels and air inlet pipe are concentric ring-shaped or snail shape.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010105095601A CN101961633B (en) | 2010-10-15 | 2010-10-15 | Unsym-trimethyl benzene continuous oxidation reaction equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010105095601A CN101961633B (en) | 2010-10-15 | 2010-10-15 | Unsym-trimethyl benzene continuous oxidation reaction equipment |
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| Publication Number | Publication Date |
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| CN101961633A CN101961633A (en) | 2011-02-02 |
| CN101961633B true CN101961633B (en) | 2012-05-23 |
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| CN2010105095601A Active CN101961633B (en) | 2010-10-15 | 2010-10-15 | Unsym-trimethyl benzene continuous oxidation reaction equipment |
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101972623B (en) * | 2010-10-15 | 2012-05-23 | 江苏正丹化学工业股份有限公司 | Continuous oxidation reaction kettle for trimethyl benzene |
| GB201810380D0 (en) * | 2018-06-25 | 2018-08-08 | Rosehill Polymers Group Ltd | Continuous reaction system,vessel and method |
| CN110746435B (en) * | 2019-10-31 | 2022-04-29 | 曹正国 | Method for producing pyromellitic dianhydride by low-temperature liquid-phase continuous oxidation of durene |
| CN110835327A (en) * | 2019-11-22 | 2020-02-25 | 江苏正丹化学工业股份有限公司 | Trimellitic anhydride continuous oxidation safety production control system and control method |
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| US5372790A (en) * | 1991-01-18 | 1994-12-13 | The Dow Chemical Company | Vertical continuous reactor |
| CN1594302A (en) * | 2004-07-15 | 2005-03-16 | 中国石油化工股份有限公司 | Process for continuous preparation of trimellitic anhydride by step catalytic oxidation process |
| CN101972623A (en) * | 2010-10-15 | 2011-02-16 | 镇江正丹化学工业有限公司(外商独资) | Continuous oxidation reaction kettle for trimethyl benzene |
| CN201848242U (en) * | 2010-10-15 | 2011-06-01 | 镇江正丹化学工业有限公司(外商独资) | Continuous oxidation reactor for unsym-trimethyl benzene |
| CN201848244U (en) * | 2010-10-15 | 2011-06-01 | 镇江正丹化学工业有限公司(外商独资) | Unsymtrimethyl benzene continuous oxidizing reaction device |
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- 2010-10-15 CN CN2010105095601A patent/CN101961633B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5372790A (en) * | 1991-01-18 | 1994-12-13 | The Dow Chemical Company | Vertical continuous reactor |
| CN1594302A (en) * | 2004-07-15 | 2005-03-16 | 中国石油化工股份有限公司 | Process for continuous preparation of trimellitic anhydride by step catalytic oxidation process |
| CN101972623A (en) * | 2010-10-15 | 2011-02-16 | 镇江正丹化学工业有限公司(外商独资) | Continuous oxidation reaction kettle for trimethyl benzene |
| CN201848242U (en) * | 2010-10-15 | 2011-06-01 | 镇江正丹化学工业有限公司(外商独资) | Continuous oxidation reactor for unsym-trimethyl benzene |
| CN201848244U (en) * | 2010-10-15 | 2011-06-01 | 镇江正丹化学工业有限公司(外商独资) | Unsymtrimethyl benzene continuous oxidizing reaction device |
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