CN217556096U - Pyridine on-line recovery system in diosmin production - Google Patents
Pyridine on-line recovery system in diosmin production Download PDFInfo
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- CN217556096U CN217556096U CN202220942172.0U CN202220942172U CN217556096U CN 217556096 U CN217556096 U CN 217556096U CN 202220942172 U CN202220942172 U CN 202220942172U CN 217556096 U CN217556096 U CN 217556096U
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Abstract
The utility model discloses an online recovery system of pyridine in diosmin production belongs to solvent recovery technical field in diosmin production. The device comprises an online dehydration device connected with a reaction kettle, wherein the online dehydration device comprises a heating reboiling chamber, a packing layer and a first-stage condenser, the heating reboiling chamber is connected with a solvent return port on the reaction kettle through a return pipe, the packing layer is connected with an azeotropic steam outlet on the reaction kettle through a steam pipe, and a circulation passage for online recovery and reuse of pyridine is formed among the azeotropic steam outlet, the packing layer, the heating reboiling chamber, a high-component outlet and the solvent return port; the pyridine on-line recovery system also comprises a secondary condenser, a pyridine recovery temporary storage tank, a sodium hydroxide water separation tank and a rectifying tower; a vacuum pump is arranged between the pyridine recovery temporary storage tank and the sodium hydroxide water distribution tank, and the vacuum pump is connected with a tail gas treatment system. On one hand, the recovery rate and the recovery concentration of the pyridine are improved, and on the other hand, the environment friendliness of the discharged tail gas is ensured.
Description
Technical Field
The utility model relates to a pyridine recovery system especially relates to an online recovery system of pyridine in diosmin production, belongs to solvent recovery technical field in the diosmin production.
Background
Diosmin, also called diosmin (molecular formula: C) 28 H 32 O 15 Molecular weight: 608.54 Is a flavonoid medicine which is prepared by semisynthesis by taking hesperidin extracted from natural immature bitter orange as a raw material and has the main reaction process as follows: adding hesperidin, iodine and acid-binding agent (such as sodium hydroxide, sodium carbonate, potassium carbonate, sodium acetate, potassium acetate and the like) into a reaction kettle, adding pyridine serving as a solvent, stirring, heating, refluxing, cleaning, purifying, drying, crushing and the like to obtain a finished diosmin product. Wherein, pyridine which is a reaction solvent is volatile and has foul smell (the maximum allowable concentration is 5 ppm), trace leakage can not be tolerated by field operators, and the steam and air form explosive mixture and cause combustion explosion when meeting open fire (high heat energy); if high heat is encountered, the internal pressure of the container is increased, and the danger of cracking and explosion is caused.
Therefore, the solvent pyridine needs to be recovered, but the following technical problems exist:
1. after the reaction in the reaction kettle is finished, recovering solvent pyridine under reduced pressure, wherein the overall recovery rate of pyridine is about 70%; after recovery, adding a solvent or water for crystallization, and recovering part of pyridine from the mother liquor, but the pyridine recovery rate is reduced due to the addition of a large amount of crystallization solvent or water, the overall recovery rate of pyridine is about 85%, and the rest of pyridine enters sewage and waste gas, which has great influence on the environment and also causes waste of raw materials;
2. in the recovery treatment of the pyridine recovery liquid, a vacuum pump is generally adopted to improve the concentration efficiency, but the arrangement of the vacuum pump will cause part of pyridine to be pumped into a vacuum system and finally discharged as waste gas, which not only causes environmental pollution, but also causes waste of raw materials and the like.
The prior art CN205056003U discloses an on-line dehydration system for diosmin production, which comprises a reaction kettle, wherein a heating core is arranged at the bottom of the reaction kettle; the rotation control system comprises a motor and a stirring paddle, the stirring paddle is arranged at the position of a central shaft of the reaction kettle, and one end of the stirring paddle extends out of the reaction kettle and is connected with the motor; the rectification recovery tower comprises a condensing unit, a packing unit and a heating reboiling chamber, wherein the packing unit is connected with a steam outlet, and the heating reboiling chamber is connected with a reflux inlet; a water storage tank connected with the water outlet; and the steam boiler is connected with the water storage tank through a second water conveying pipe, connected with the heating reboiling chamber through a second steam pipeline and the like. CN213726490U discloses a pyridine recovery system for diosmin production, wherein the recovery of pyridine separated from steam in a reaction system in online production is realized through the arrangement of an online water separator, a second condensation unit and a pyridine collection tank; the reaction kettle is connected with the pyridine collecting tank, so that the recovery of the pyridine with water after the reaction system is finished is realized, and the recovery rate of the pyridine is ensured to be more than 98.5%; meanwhile, the on-line water separator, the second condensing unit and the like are arranged, so that the conversion rate of the diosmin production reaction system is ensured. CN208586233U discloses a diosmin production system which is beneficial to pyridine leakage prevention and recovery, and utilizes the characteristic of iodine sublimation to arrange a novel iodine feeding barrel, so that when the temperature in a reaction kettle rises to a certain value, the automatic feeding of iodine is realized, and the pyridine leakage is reduced.
Disclosure of Invention
The utility model aims to overcome the defects of the prior art and provides an online pyridine recovery system in diosmin production. In the technical scheme, the problems that the recovery rate of pyridine is low, and the recovery process is discharged by waste gas to cause environmental pollution and simultaneously cause raw material waste and the like are effectively solved.
In order to achieve the technical purpose, the following technical scheme is proposed:
an online pyridine recovery system in diosmin production comprises an online dehydration device connected with a reaction kettle, wherein the online dehydration device comprises a heating reboiling chamber arranged at the lower part, a packing layer arranged at the middle part and a first-stage condenser arranged at the upper part, a high component outlet on the heating reboiling chamber is connected with a solvent return port on the reaction kettle through a return pipe, the packing layer is connected with an azeotropic steam outlet on the reaction kettle through a steam pipe, and a circulation path for online pyridine recovery and reuse is formed among the azeotropic steam outlet, the packing layer, the heating reboiling chamber, the high component outlet and the solvent return port;
the pyridine on-line recovery system also comprises a secondary condenser, a pyridine recovery temporary storage tank, a sodium hydroxide water diversion tank and a rectifying tower, wherein the secondary condenser is connected with a low-component outlet on the primary condenser, the secondary condenser is connected with the pyridine recovery temporary storage tank, the pyridine recovery temporary storage tank is connected with the sodium hydroxide water diversion tank, the sodium hydroxide water diversion tank is connected with the rectifying tower, the rectifying tower is connected with a pyridine preparation tank, the pyridine preparation tank is connected with a pyridine inlet on the reaction kettle, and the water diversion pyridine which is not recovered by the on-line dehydration device is recovered by the device, so that the recovery rate of the pyridine is improved, the circular economy is realized, and meanwhile, the stability of the working condition environment is ensured;
a vacuum pump is arranged between the pyridine recovery temporary storage tank and the sodium hydroxide water separation tank, and the arrangement is used for improving the concentration of pyridine entering the sodium hydroxide water separation tank, namely improving the concentration efficiency of the pyridine; the vacuum pump is connected with a tail gas treatment system, the tail gas treatment system comprises a three-stage condenser and a hydrochloric acid washing tower, an upper feed inlet of the three-stage condenser is connected with the vacuum pump, a high-component outlet on the three-stage condenser is connected with a pyridine recovery temporary storage tank, so that the pyridine entering the vacuum system is condensed and recovered, and the pyridine recovery rate can be improved by 5%; the low-component outlet on the third-stage condenser is connected with a hydrochloric acid washing tower, and the treatment of unrecovered pyridine is carried out by utilizing the characteristic that pyridine and acid are easy to react, wherein the pyridine and the hydrochloric acid react to generate pyridine hydrochloride, the pyridine hydrochloride is stable in chemical property and easy to dissolve in water for subsequent treatment, more than 98% of pyridine waste gas can be treated by the device, and the formed pyridine hydrochloride can be used for other purposes.
Further, the leakage fluid dram of reation kettle bottom is connected with solid-liquid separation equipment, and the last liquid outlet of solid-liquid separation equipment is connected with pyridine recovery jar of keeping in, and this setting is retrieved the pyridine of taking water in the reation kettle, and then improves the rate of recovery of pyridine to and realize circular economy.
Furthermore, a heating jacket is sleeved outside the reaction kettle.
Furthermore, a heat-insulating jacket is sleeved outside the steam pipe, so that azeotropic steam of water and pyridine can stably enter the online dehydration device.
Further, the hydrochloric acid washing tower is connected with a sodium hydroxide water separation tank, pyridine hydrochloride reacts with sodium hydroxide to form free pyridine again, then the pyridine can be concentrated and collected (the pyridine is evaporated out earlier than water under the strong alkaline condition), and then the pyridine is rectified to ensure that the concentration of the collected pyridine is more than 99%, and the pyridine can enter a pyridine preparation tank and then be directly used.
Furthermore, the hydrochloric acid washing tower is connected with the alkali liquor washing tower, and hydrogen chloride gas volatilized from the hydrochloric acid washing tower is absorbed, so that environment friendliness of tail gas emission is guaranteed.
In this technical scheme, according to the actual demand, can be provided with the temperature at reation kettle, condenser etc. and set up regulation and control valve etc. on each pipeline.
In the present invention, the positional relationships such as "lower", "middle", "upper", "between", "bottom", "outer" and the like are defined according to the actual usage state, and are common terms in the art and in the actual usage process of the person skilled in the art.
In the description of the present technical solution, it should be noted that, unless explicitly stated or limited otherwise, the terms "disposed" and "connected" should be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
By adopting the technical scheme, the beneficial technical effects brought are as follows:
1. in the utility model, the on-line dehydration device is connected with the reaction kettle, the on-line dehydration device comprises a heating reboiling chamber arranged at the lower part, a packing layer arranged at the middle part and a first-stage condenser arranged at the upper part, a circulation path for recovering and recycling pyridine on line is formed among the azeotropic steam outlet, the packing layer, the heating reboiling chamber, the high component outlet and the solvent return port, the continuous dehydration in the reaction process can be realized by the arrangement, the nearly anhydrous state in the reaction kettle is maintained until the reaction is finished, and the reaction efficiency and the quality in the reaction kettle are ensured;
2. the utility model discloses in, pyridine on-line recovery system still includes second grade condenser, pyridine recovery temporary storage tank, sodium hydroxide knockout drum and rectifying column, sets up and will retrieve through online dewatering device unrecovered knockout drum pyridine, and then improves the rate of recovery of pyridine to and realize the circular economy, simultaneously, guarantee the stability of operating mode environment;
3. the utility model discloses in, pyridine is retrieved and is kept in and be provided with the vacuum pump between the jar and the sodium hydroxide jar that divides, should set up in order to improve the pyridine concentration that gets into in the sodium hydroxide jar that divides, improves pyridine concentration efficiency promptly. The vacuum pump is connected with a tail gas treatment system, the pyridine entering the vacuum system is condensed and recycled, and the pyridine recycling rate can be improved by 5%. The device comprises a three-stage condenser, a hydrochloric acid washing tower, a pyridine washing tower and a pyridine washing tower, wherein the low-component outlet on the three-stage condenser is connected with the hydrochloric acid washing tower, the treatment of unrecovered pyridine is carried out by utilizing the characteristic that pyridine and acid are easy to react, the pyridine reacts with the hydrochloric acid to generate pyridine hydrochloride, the pyridine hydrochloride is stable in chemical property and easy to dissolve in water for subsequent treatment, more than 98% of pyridine waste gas can be treated by the device, and the formed pyridine hydrochloride can be used for other purposes;
fourth, the utility model discloses in, the leakage fluid dram of reation kettle bottom is connected with solid-liquid separation equipment, and liquid outlet and pyridine recovery temporary storage tank are connected on the solid-liquid separation equipment, and this setting is retrieved the pyridine of taking water in reation kettle, and then improves the rate of recovery of pyridine to and realize circulation economy etc..
Drawings
FIG. 1 is a schematic view of the working state of the present invention;
in the figure: 1. the system comprises a reaction kettle, 2, an online dehydration device, 21, a heating reboiling chamber, 22, a packing layer, 23, a primary condenser, 3, a return pipe, 4, a steam pipe, 5, a secondary condenser, 6, a pyridine recovery temporary storage tank, 7, a sodium hydroxide water separation tank, 8, a rectification tower, 9, a vacuum pump, 10, a tertiary condenser, 11, a hydrochloric acid washing tower, 12, a solid-liquid separation device, 13, a heating jacket, 14, a heat preservation jacket, 15, an alkali liquor washing tower, 16 and a pyridine preparation tank.
Detailed Description
In the following, the technical solutions in the embodiments of the present invention are clearly and completely described, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
Example 1
As shown in fig. 1: an online pyridine recovery system in diosmin production comprises an online dehydration device 2 connected with a reaction kettle 1, wherein the online dehydration device 2 comprises a heating reboiling chamber 21 arranged at the lower part, a packing layer 22 arranged at the middle part and a first-stage condenser 23 arranged at the upper part, an upper component outlet of the heating reboiling chamber 21 is connected with a solvent return port of the reaction kettle 1 through a return pipe 3, the packing layer 22 is connected with an azeotropic steam outlet of the reaction kettle 1 through a steam pipe 4, and a circulation passage for online pyridine recovery and reuse is formed among the azeotropic steam outlet, the packing layer 22, the heating reboiling chamber 21, the high component outlet and the solvent return port, so that continuous dehydration in the reaction process can be realized, a nearly anhydrous state in the reaction kettle 1 is maintained until the reaction is finished, and the reaction efficiency and quality in the reaction kettle 1 are ensured;
the pyridine on-line recovery system further comprises a second-stage condenser 5, a pyridine recovery temporary storage tank 6, a sodium hydroxide water separation tank 7 and a rectifying tower 8, wherein the second-stage condenser 5 is connected with a low-component outlet on a first-stage condenser 23, the second-stage condenser 5 is connected with the pyridine recovery temporary storage tank 6, the pyridine recovery temporary storage tank 6 is connected with the sodium hydroxide water separation tank 7, the sodium hydroxide water separation tank 7 is connected with the rectifying tower 8, the rectifying tower 8 is connected with a pyridine preparation tank 16, the pyridine preparation tank 16 is connected with a pyridine inlet on the reaction kettle 1, the pyridine on-line recovery system recovers the dehydrated pyridine which is not recovered by the on-line dehydration device 2, the recovery rate of the pyridine is improved, the circular economy is realized, and meanwhile, the stability of a working condition environment is guaranteed;
a vacuum pump 9 is arranged between the pyridine recovery temporary storage tank 6 and the sodium hydroxide water separation tank 7, and the arrangement is used for improving the concentration of pyridine entering the sodium hydroxide water separation tank 7, namely improving the pyridine concentration efficiency; the vacuum pump 9 is connected with a tail gas treatment system, the tail gas treatment system comprises a three-stage condenser 10 and a hydrochloric acid washing tower 11, an upper feed inlet of the three-stage condenser 10 is connected with the vacuum pump 9, a high component outlet of the three-stage condenser 10 is connected with a pyridine recovery temporary storage tank 6, so that the pyridine entering the vacuum system is condensed and recovered, and the pyridine recovery rate can be improved by 5%; the low component outlet of the third-stage condenser 10 is connected with a hydrochloric acid washing tower 11, and the property that pyridine and acid are easy to react is utilized to carry out treatment of unrecovered pyridine, wherein pyridine and hydrochloric acid react to generate pyridine hydrochloride, the pyridine hydrochloride is stable in chemical property and easy to dissolve in water for subsequent treatment, more than 98% of pyridine waste gas can be treated by the device, and the formed pyridine hydrochloride can be used for other purposes.
Wherein, the heating jacket 13 is sleeved outside the reaction kettle 1 to provide conditions for the reaction in the reaction kettle 1; the steam pipe 4 is externally sleeved with a heat-insulating jacket 14 to ensure that azeotropic steam of water and pyridine stably enters the online dehydration device 2.
Example 2
This embodiment will be further described based on example 1, in which pyridine with water discharged from the reaction vessel 1 after the completion of the reaction is recovered.
The liquid outlet at the bottom of the reaction kettle 1 is connected with a solid-liquid separation device 12, a liquid outlet on the solid-liquid separation device 12 is connected with a pyridine recovery temporary storage tank 6, pyridine with water in the reaction kettle 1 is recovered by the aid of the device, the recovery rate of the pyridine is further improved, and circular economy is realized.
Example 3
This embodiment will be further described based on examples 1 to 2, in which pyridine with water discharged from the reaction vessel 1 after the completion of the reaction is recovered.
The hydrochloric acid washing tower 11 is connected with the sodium hydroxide water separation tank 7, so that pyridine hydrochloride reacts with sodium hydroxide to form free pyridine again, then the pyridine can be concentrated and collected (under the strong alkaline condition, the pyridine is evaporated out earlier than water), and then the pyridine is rectified to ensure that the concentration of the collected pyridine is more than 99%, and the pyridine can enter the pyridine preparation tank 16 and then can be directly used.
In addition, the hydrochloric acid washing tower 11 is connected with the alkali liquor washing tower 15, and hydrogen chloride gas volatilized in the hydrochloric acid washing tower 11 is absorbed, so that environment friendliness of discharged tail gas is guaranteed.
Claims (6)
1. The pyridine on-line recovery system in diosmin production comprises an on-line dehydration device (2) connected with a reaction kettle (1), and is characterized in that: the online dehydration device (2) comprises a heating reboiling chamber (21) arranged at the lower part, a packing layer (22) arranged at the middle part and a first-stage condenser (23) arranged at the upper part, a high component outlet on the heating reboiling chamber (21) is connected with a solvent return port on the reaction kettle (1) through a return pipe (3), the packing layer (22) is connected with an azeotropic steam outlet on the reaction kettle (1) through a steam pipe (4), and a circulation path for online recovery and reuse of pyridine is formed among the azeotropic steam outlet, the packing layer (22), the heating reboiling chamber (21), the high component outlet and the solvent return port;
the pyridine on-line recovery system further comprises a second-stage condenser (5), a pyridine recovery temporary storage tank (6), a sodium hydroxide water separation tank (7) and a rectifying tower (8), wherein the second-stage condenser (5) is connected with a low component outlet on the first-stage condenser (23), the second-stage condenser (5) is connected with the pyridine recovery temporary storage tank (6), the pyridine recovery temporary storage tank (6) is connected with the sodium hydroxide water separation tank (7), the sodium hydroxide water separation tank (7) is connected with the rectifying tower (8), the rectifying tower (8) is connected with a pyridine preparation tank (16), and the pyridine preparation tank (16) is connected with a pyridine inlet on the reaction kettle (1);
pyridine is retrieved and is stored in jar (6) and be provided with vacuum pump (9) between sodium hydroxide water knockout drum (7), vacuum pump (9) are connected with tail gas processing system, and tail gas processing system includes tertiary condenser (10) and hydrochloric acid scrubbing tower (11), and tertiary condenser (10) upper feed inlet is connected with vacuum pump (9), and tertiary condenser (10) is gone up the component export and is retrieved with pyridine and store in jar (6) and be connected, and tertiary condenser (10) is gone up the low component export and is connected with hydrochloric acid scrubbing tower (11).
2. The system for on-line recovery of pyridine in diosmin production according to claim 1, wherein: a liquid outlet at the bottom of the reaction kettle (1) is connected with a solid-liquid separation device (12), and a liquid outlet on the solid-liquid separation device (12) is connected with a pyridine recovery temporary storage tank (6).
3. The system for the on-line recovery of pyridine in diosmin production according to claim 1, wherein: the heating jacket (13) is sleeved outside the reaction kettle (1).
4. The system for on-line recovery of pyridine in diosmin production according to claim 1, wherein: and a heat-insulating jacket (14) is sleeved outside the steam pipe (4).
5. The system for on-line recovery of pyridine in diosmin production according to claim 1, wherein: the hydrochloric acid washing tower (11) is connected with the sodium hydroxide water separation tank (7).
6. The system for on-line recovery of pyridine in diosmin production according to claim 1, wherein: the hydrochloric acid washing tower (11) is connected with an alkali liquor washing tower (15).
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220942172.0U CN217556096U (en) | 2022-04-22 | 2022-04-22 | Pyridine on-line recovery system in diosmin production |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220942172.0U CN217556096U (en) | 2022-04-22 | 2022-04-22 | Pyridine on-line recovery system in diosmin production |
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| CN202220942172.0U Active CN217556096U (en) | 2022-04-22 | 2022-04-22 | Pyridine on-line recovery system in diosmin production |
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| PE01 | Entry into force of the registration of the contract for pledge of patent right |
Denomination of utility model: A Pyridine Online Recovery System in Diosmin Production Effective date of registration: 20230711 Granted publication date: 20221011 Pledgee: China Construction Bank Pengzhou Sub branch Pledgor: CHENGDU YAZHONG BIO-PHARMACEUTICAL Co.,Ltd. Registration number: Y2023510000177 |
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| PE01 | Entry into force of the registration of the contract for pledge of patent right |