CN213475848U

CN213475848U - Kettle type reaction system for synthesizing methylal through methanol liquid-phase one-step oxidation

Info

Publication number: CN213475848U
Application number: CN202021611139.7U
Authority: CN
Inventors: 邓志勇; 张传辉
Original assignee: Sichuan Longmen Zhichuang Environmental Protection New Material Technology Co ltd
Current assignee: Sichuan Longmen Zhichuang Environmental Protection New Material Technology Co ltd
Priority date: 2020-08-05
Filing date: 2020-08-05
Publication date: 2021-06-18
Anticipated expiration: 2030-08-05

Abstract

The utility model discloses a kettle type reaction system for synthesizing methylal by one-step oxidation of methanol liquid phase, which relates to the field of chemical industry and comprises a reactor, a gas-liquid separation system and a rectification system; the reactor is provided with a methanol feeding pipeline and an oxygen feeding pipeline, the reactor is also provided with a stirring assembly for stirring a methanol liquid phase in the reactor, the oxygen feeding pipeline is provided with a first pump body; the gas-liquid separation system is communicated with the reactor through a gas phase discharge pipeline, a second pump body and a product discharge valve are arranged on the gas phase discharge pipeline, and a gas discharge pipeline is arranged on the gas-liquid separation system; the rectification system is communicated with the gas-liquid separation system through a liquid-phase discharge pipeline, a third pump body is arranged on the liquid-phase discharge pipeline, a methylal discharge pipeline is arranged on the rectification system, the reactor produces methylal, the gas-liquid separation system separates a gas-phase mixture, and finally the product is obtained through purification of the rectification system.

Description

Kettle type reaction system for synthesizing methylal through methanol liquid-phase one-step oxidation

Technical Field

The utility model relates to a chemical industry field especially relates to a reaction system that is used for methyl alcohol liquid phase one step oxidation to synthesize methylal.

Background

Methylal, also known as Dimethoxymethane (DMM), has low toxicity, low boiling point and good solubility, and has wide applications in the fields of oil additives, insecticides, leather polish, rubber industry, paints, cosmetics, pharmaceuticals, and the like. Currently, the industry mainly adopts a two-step method for production, wherein methanol is firstly oxidized into formaldehyde, and then the formaldehyde and the methanol are condensed into methylal under the action of a liquid acid catalyst.

However, the method has the problems of large equipment investment, high energy consumption, serious environmental pollution and the like, and in recent years, the methanol one-step oxidation method for synthesizing methylal gradually receives wide attention of researchers, has the characteristics of short process route, low production cost and small environmental pollution, and has great industrial application prospect.

Patent CN202410666U provides a reation kettle of industry preparation methylal, including reation kettle and join in marriage in the agitator of cauldron body, reation kettle contains inside and outside bilayer structure, and this patent advantage lies in providing more even heating effect for reation kettle's stirring effect preferred, but the device also can only be used for aldol condensation technology. Is not suitable for the use of the methanol one-step oxidation synthesis process, so that the kettle type reaction system for synthesizing methylal by methanol liquid-phase one-step oxidation is urgently needed to be developed, and the problem of the vacancy of the existing equipment is solved.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a cauldron formula reaction system that is used for methyl alcohol liquid phase one-step oxidation to synthesize methylal solves the problem of present equipment vacancy.

In order to realize the purpose, the utility model discloses a technical scheme is: a reaction system for synthesizing methylal by methanol liquid-phase one-step oxidation is characterized in that: comprises a reactor, a gas-liquid separation system and a rectification system; the reactor is provided with a methanol feeding pipeline, an oxygen feeding pipeline is provided with an oxygen feeding valve, the reactor is also provided with a stirring assembly for stirring a methanol liquid phase in the reactor, the oxygen feeding pipeline is provided with a first pump body; the gas-liquid separation system is communicated with the reactor through a gas phase discharge pipeline, a second pump body and a product discharge valve are arranged on the gas phase discharge pipeline, and a gas discharge pipeline is arranged on the gas-liquid separation system; the rectification system is communicated with the gas-liquid separation system through a liquid phase discharge pipeline, a third pump body is arranged on the liquid phase discharge pipeline, a methylal discharge pipeline is arranged on the rectification system, and a discharge valve is arranged on the methylal discharge pipeline.

By adopting the technical scheme, the effect of continuously supplying raw materials into the reactor is achieved through the methanol feeding pipeline and the oxygen feeding pipeline, continuous production is realized, the stirring assembly on the reactor enables methanol and oxygen in the reactor to be mixed and react more fully, and then the product is separated and purified through the gas-liquid separation system and the rectification system, so that the product quality is improved, and the whole process has the characteristics of simplicity and convenience in operation, high reaction efficiency and the like; provides a choice for the industrialization of synthesizing methylal by one-step oxidation of methanol liquid phase.

Further, the stirring subassembly is including fixing motor and the (mixing) shaft at reactor outer wall top, the suit is equipped with initiative conical gear on the output shaft of motor, be equipped with passive conical gear on the (mixing) shaft, passive conical gear and initiative conical gear meshing, be equipped with a plurality of stirring paddle leaf on the (mixing) shaft, (mixing) shaft and stirring paddle leaf are cavity form setting and the inside cavity of stirring paddle leaf and the cavity intercommunication of (mixing) shaft, a plurality of air vent has been seted up on the stirring paddle leaf, the one end and the oxygen feed line intercommunication of stirring paddle leaf are kept away from to the (mixing) shaft.

Further, the reactor is also provided with an inert gas feeding pipeline, and the inert gas feeding pipeline is provided with an inert gas valve.

Further, an inert gas heater is arranged on the inert gas feeding pipeline.

Further, an oxygen heater is arranged on the oxygen feeding pipeline.

Furthermore, the reactor is also provided with a gas sampling analysis pipeline, and the gas sampling analysis pipeline is provided with a gas sampling valve.

Further, the reactor is also provided with a pressure gauge for monitoring the pressure of the inner cavity.

Further, the first pump body, the second pump body and the third pump body are metering pumps.

Further, the reactor is a reaction kettle, the rectifying system is a rectifying tower, and the gas-liquid separation system is a gas-liquid separator

Compared with the prior art, the utility model has the advantages of: the whole kettle type reactor produces methylal by taking the reaction kettle as the reactor, then carries out gas-liquid separation on a gas-liquid mixture containing the methylal through a gas-liquid separator, and finally purifies the methylal through a rectifying tower to obtain a methylal product, wherein the whole process has the characteristics of simple and convenient operation, high reaction efficiency and the like; provides a choice for the industrialization of synthesizing methylal by one-step oxidation of methanol liquid phase.

Drawings

FIG. 1 is a schematic view of the present embodiment;

FIG. 2 is a schematic view of the reaction system.

In the figure: 1. a reactor; 11. an inert gas feed line; 111. an inert gas valve; 112. an inert gas heater; 12. a methanol feed line; 121. a first pump body; 13. an oxygen feed line; 131. an oxygen feed valve; 132. an oxygen heater; 14. a gas sampling analysis pipeline; 141. a gas sampling valve; 15. a gas phase discharge line; 151. a product discharge valve; 152. a second pump body; 16. a pressure gauge; 2. a stirring assembly; 21. a motor; 22. a driving bevel gear; 23. a driven bevel gear; 24. a stirring shaft; 25. stirring the paddle; 251. a vent hole; 3. a gas-liquid separation system; 31. a gas discharge conduit; 32. a gas discharge valve; 33. a liquid phase discharge line; 331. a third pump body; 4. a rectification system; 41. a methylal discharge line; 411. a discharge valve; 42. an impurity discharge line; 421. an impurity discharge valve.

Detailed Description

The present invention will be further explained below.

Example (b):

referring to fig. 1, a tank type reaction system for synthesizing methylal by liquid-phase one-step oxidation of methanol is shown, which relates to the field of chemical industry and comprises a reactor 1, a gas-liquid separation system 3 and a rectification system 4. In this embodiment, it is preferable that the reactor 1 is a reaction kettle, the rectifying system 4 is a rectifying tower, and the gas-liquid separation system 3 is a gas-liquid separator.

Referring to fig. 1 and 2, a methanol feed line 12 and an oxygen feed line 13 are provided on the reactor 1 to achieve the effect of continuously supplying the raw materials into the reactor 1, so that continuous production can be achieved, and for the stability of methanol raw material supply, a first pump body 121 is provided on the methanol feed line 12, in this embodiment, the first pump body 121 is preferably a metering pump, so that the flow of methanol can be more stable. Meanwhile, for the consideration of factors such as equipment operation and later equipment maintenance, the oxygen feed line 13 is also provided with an oxygen feed valve 131. In order to enable the methanol and oxygen in the reactor 1 to react more fully, the reactor 1 is further provided with a stirring assembly 2 for stirring a methanol liquid phase in the reactor 1, specifically, the stirring assembly 2 comprises a motor 21 and a stirring shaft 24 which are fixed on the top of the outer wall of the reactor 1, an active bevel gear 22 is sleeved on the output end of the motor 21, a passive bevel gear 23 is arranged on the stirring shaft 24, the passive bevel gear 23 is meshed with the active bevel gear 22, and the stirring shaft 24 is further provided with a plurality of stirring blades 25, namely, the stirring shaft 24 can rotate under the driving of the motor 21, and further, the plurality of stirring blades 25 can rotate under the driving of the motor 21, so as to realize the stirring effect on the methanol liquid phase in the stirring reactor 1. And in order to further improve the contact surface between oxygen and methanol, as shown in fig. 2, in this embodiment, the stirring shaft 24 and the stirring blades 25 are both arranged in a hollow shape, the inner cavity of the stirring blade 25 is communicated with the cavity of the stirring shaft 24, the blades are provided with a plurality of vent holes 251, one end of the stirring shaft 24 away from the stirring blade 25 is communicated with the oxygen feeding pipeline 13, wherein the oxygen feeding pipeline 13 is connected with the stirring shaft 24 through a sealed bearing, and through the arrangement, the outlet of oxygen is below the liquid level of methanol, and when oxygen is introduced into the reactor 1, oxygen bubbles are generated in the reactor 1, so as to increase the contact surface between oxygen and methanol. And the oxygen is discharged through the vent holes 251 on the stirring blade, namely in the continuous production process, countless tiny oxygen bubbles are formed under the continuous rotation of the stirring blade, and further, the oxygen is favorably and uniformly dispersed in the methanol liquid phase, the contact surface between the oxygen and the methanol is further increased, and the oxygen consumed in the methanol liquid phase can be supplemented more quickly. And because the methanol liquid phase one-step oxidation synthesis methylal technology is sensitive to temperature, the reduction of temperature will reduce the methanol conversion rate and methylal selectivity, so the oxygen heater 132 is arranged on the oxygen feeding pipeline 13, the oxygen heater 132 heats the oxygen, and the problem of low oxygen activity of the oxygen at room temperature after entering the reactor 1 through the air hole is solved. When the heated oxygen enters the reactor 1 through the air holes, the activity of the oxygen is improved, so that the reaction of the oxygen and the methanol is more sufficient.

Referring to fig. 1, it is shown that an inert gas feeding line 11 is arranged on a reactor 1, an inert gas valve 111 is arranged on the inert gas feeding line 11, inert gas is introduced into the reactor 1 through the inert gas feeding line 11, and before a start-up reaction, impurities in the reactor 1 are discharged by continuously introducing the inert gas into the reactor 1, so that the influence of the impurities in the reactor 1 on the generation of methylal after the start-up reaction is reduced. And the inert gas can be continuously introduced after the start-up, so that the inert gas maintains the pressure in the reactor 1, the solubility of oxygen in the liquid phase is increased, and the reaction in the reactor 1 is kept to be orderly carried out. Similarly to the reason for the need to heat oxygen, heating is also required for the inert gas, that is, an inert gas heater 112 is provided on the inert gas feed line 11, and the possibility of the influence on the temperature inside the reactor 1 when the inert gas is fed can be reduced by the provision of the inert gas heater 112.

Referring to fig. 1, since the reaction product in the reactor 1 needs to be further purified, that is, in this embodiment, the gas-liquid separation system 3 is used to primarily separate the reaction product, the gas-liquid separation system 3 is communicated with the reactor 1 through the gas-phase discharge pipeline 15, wherein the gas-phase discharge pipeline 15 is provided with a second pump body 152 and a product discharge valve 151, the gas discharge pipeline 31 is provided on the gas-liquid separation system 3, in this embodiment, the second pump body 152 is preferably a metering pump, so that the reaction product can more stably flow into the gas-liquid separation system 3, and the gas-liquid separation system 3 can stably work. The liquid phase product after the gas-liquid separation system 3 separation still needs further purification treatment, and in this embodiment, rectification system 4 is used for purifying the liquid phase product, and rectification system 4 communicates with gas-liquid separation system 3 through liquid phase discharging pipeline 33, is equipped with the third pump body 331 on the liquid phase discharging pipeline 33, is equipped with methylal discharging pipeline 41 on the rectification system 4, and methylal discharging pipeline 41 is equipped with bleeder valve 411. In this embodiment, the third pump body 331 is also preferably a metering pump, so that the liquid phase product can flow into the gas-liquid separation system 3 more stably, and the rectification system 4 can work stably.

Referring to fig. 1, the reactor 1 is further provided with a gas sampling and analyzing pipeline 14, and the gas sampling and analyzing pipeline 14 is provided with a gas sampling valve 141. Through the arrangement of the gas sampling and analyzing pipeline 14, the gas in the reactor 1 can be conveniently sampled in the process of debugging the process, so that the analysis of the reaction state in the reactor 1 is beneficial to debugging the equipment and the synthesis process. Further, in order to monitor the state of the gas pressure in the reactor 1, a pressure gauge 16 is further arranged in the reactor 1 for monitoring the gas pressure in the reactor 1, so that the state in the reactor 1 can be known when the equipment runs frequently, and the occurrence probability of economic loss caused by incapability of finding when abnormality occurs in the reactor 1 is reduced.

The specific using process is as follows: A. optionally turning on the oxygen heater 132 and the inert gas heater 112; B. introducing inert gas into the reactor 1 through an inert gas feeding pipeline 11 to empty the reactor 1; C. methanol taking part in the reaction enters the reactor 1 through a methanol feeding pipeline 12; D. when the stirring component 2 is started, oxygen participating in the reaction enters the reaction system 1 through the oxygen feeding pipeline 13 and the vent hole 251, and meanwhile, inert gas is introduced to maintain the pressure in the reaction system 1; E. continuously converting methanol in the reactor 1 into methylal under the action of a catalyst; F. the unreacted raw materials and the gaseous methylal flow to the gas-liquid separation system 3 through the gas-phase discharge pipeline 15 under the action of the second pump body 152, and oxygen and inert gases are discharged through the gas discharge pipeline 31 under the action of the gas-liquid separation system 3; G. the mixed liquid of methanol and methylal flows to the rectification system 4 through the third pump body 331, and the methanol and methylal are separated and discharged respectively under the action of the rectification system 4.

In the embodiment, the specific connection mode of each mentioned part adopts conventional means such as bolts, rivets, welding and the like mature in the prior art, machines, parts and equipment adopt conventional models in the prior art, and circuit connection adopts a conventional connection mode in the prior art, and detailed description is omitted here.

The kettle-type reaction system for synthesizing methylal by liquid-phase one-step oxidation of methanol provided by the utility model is introduced in detail, and the principle and the implementation mode of the utility model are explained by applying specific examples, and the explanation of the above examples is only used for helping to understand the method and the core idea of the utility model; while the invention has been described in terms of specific embodiments and applications, it will be apparent to those skilled in the art that numerous variations and modifications can be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A kettle formula reaction system that is used for methyl alcohol liquid phase one-step oxidation to synthesize methylal which characterized in that: comprises a reactor (1), a gas-liquid separation system (3) and a rectification system (4);

a methanol feeding pipeline (12) and an oxygen feeding pipeline (13) are arranged on the reactor (1), a stirring assembly (2) for stirring a methanol liquid phase in the reactor (1) is further arranged on the reactor (1), an oxygen feeding valve (131) is arranged on the oxygen feeding pipeline (13), and a first pump body (121) is arranged on the methanol feeding pipeline (12);

the gas-liquid separation system (3) is communicated with the reactor (1) through a gas phase discharge pipeline (15), a second pump body (152) and a product discharge valve (151) are arranged on the gas phase discharge pipeline (15), and a gas discharge pipeline (31) is arranged on the gas-liquid separation system (3);

rectifying system (4) are through liquid phase discharging pipeline (33) and gas-liquid separation system (3) intercommunication, be equipped with the third pump body (331) on liquid phase discharging pipeline (33), be equipped with methylal discharging pipeline (41) on rectifying system (4), methylal discharging pipeline (41) are equipped with bleeder valve (411).

2. The kettle-type reaction system for liquid-phase one-step oxidation synthesis of methylal by methanol according to claim 1, wherein: stirring subassembly (2) is including fixing motor (21) and (mixing) shaft (24) at reactor (1) outer wall top, the suit is equipped with initiative conical gear (22) on the output shaft of motor (21), be equipped with passive conical gear (23) on (mixing) shaft (24), passive conical gear (23) and initiative conical gear (22) meshing, be equipped with a plurality of stirring paddle (25) on (mixing) shaft (24), (mixing) shaft (24) and stirring paddle (25) are the cavity intercommunication of cavity form setting and stirring paddle (25)'s inside cavity and (mixing) shaft (24), a plurality of air vent (251) have been seted up on stirring paddle (25), stirring shaft (24) are kept away from the one end and oxygen feed line (13) intercommunication of stirring paddle (25).

3. The kettle-type reaction system for liquid-phase one-step oxidation synthesis of methylal by methanol according to claim 1, wherein: the reactor (1) is also provided with an inert gas feeding pipeline (11), and the inert gas feeding pipeline (11) is provided with an inert gas valve (111).

4. The kettle-type reaction system for liquid-phase one-step oxidation synthesis of methylal by methanol according to claim 3, wherein: an inert gas heater (112) is arranged on the inert gas feeding pipeline (11).

5. The kettle-type reaction system for liquid-phase one-step oxidation synthesis of methylal by methanol according to claim 1, wherein: an oxygen heater (132) is arranged on the oxygen feeding pipeline (13).

6. The kettle-type reaction system for liquid-phase one-step oxidation synthesis of methylal by methanol according to claim 1, wherein: the reactor (1) is also provided with a gas sampling analysis pipeline (14), and the gas sampling analysis pipeline (14) is provided with a gas sampling valve (141).

7. The kettle-type reaction system for liquid-phase one-step oxidation synthesis of methylal by methanol according to claim 1, wherein: the reactor (1) is also provided with a pressure gauge (16) for monitoring the pressure of the internal cavity.

8. The kettle-type reaction system for the liquid-phase one-step oxidation synthesis of methylal from methanol according to any one of claims 1 to 7, characterized in that: the first pump body (121), the second pump body (152) and the third pump body (331) are metering pumps.

9. The kettle-type reaction system for the liquid-phase one-step oxidation synthesis of methylal from methanol according to any one of claims 1 to 7, characterized in that: the reactor (1) is a reaction kettle, the rectifying system (4) is a rectifying tower, and the gas-liquid separation system (3) is a gas-liquid separator.