Continuous desolventizing system

Abstract

The utility model discloses a continuous desolventizing system and belongs to the technical field of desolventizing equipment. The device comprises a storage tank, a desolventizing kettle, a first rectifying tower and an extraction receiver which are sequentially communicated, wherein the desolventizing kettle is circularly communicated with a reboiler, and the desolventizing kettle is communicated with a secondary separation assembly; the secondary separation assembly comprises a distillation kettle, a material inlet of the distillation kettle is connected with the bottom of the desolventizing kettle through a pipeline, and a gas outlet of the distillation kettle is connected with an extraction receiver through a second rectifying tower. According to the continuous desolventizing system disclosed by the utility model, the desolventizing kettle is circularly communicated with the reboiler, so that continuous desolventizing can be realized, and the working efficiency is effectively improved. Meanwhile, through the arrangement of the secondary separation assembly, on the basis of performing secondary separation on the mixture, the material flushing phenomenon caused by excessive distillation substrates can be effectively eliminated.

Description

Technical Field

[0001] The utility model belongs to the technical field of desolventizing equipment, and more specifically relates to a continuous desolventizing system. Background Art

[0002] In the field of chemical production, in order to remove or recover the solvent from the liquid solution, so that the recoverable solvent can be reused to obtain a solid or a more concentrated liquid solution, a desolventizing operation is usually required. Desolventizing equipment is divided into intermittent desolventizing and continuous desolventizing according to different desolventizing methods.

[0003] Among them, intermittent desolventization is batch desolventization. A single batch of feed can separate multiple different components by utilizing different boiling points, but each production batch requires repeated feeding, and the production efficiency is low. Compared with intermittent desolventization, continuous desolventization has higher production efficiency. However, the essence of continuous desolventization is to feed from the desolventizing kettle and utilize the separation of gas and liquid phases to achieve the purpose of desolventization. It only allows the separation of two different components, and a single desolventizing kettle cannot perform multi-component distillation. For example, in the patent CN215505526U, a continuous desolventizing device is disclosed; in the patent CN217612996U, a complete set of continuous desolventizing system is disclosed.

[0004] Both of the above patents involve technical improvements to continuous desolventization, but there is still room for optimization. For example, in the patent CN215505526U, a single desolventizing kettle cannot perform multi-component distillation. In the patent CN217612996U, although at least three different components of materials can be continuously desolventized, the problem that the same set of desolventizing equipment can only perform continuous desolventization of two different components is solved. However, after a period of actual use, it was found that the desolventizing system is prone to material rushing during the production process, which causes part of the material to enter the separation pipeline, which not only causes material waste, but also interferes with the recovery of the separated material. Utility Model Content

[0005] 1. Problems to be solved

[0006] In view of at least some of the problems existing in the above prior art, the present invention proposes a continuous desolventizing system. The present invention can realize continuous desolventizing by circulating the desolventizing kettle and the reboiler; at the same time, the material rushing phenomenon can be effectively eliminated by setting the secondary separation component.

[0007] 2. Technical solution

[0008] In order to solve the above problems, the technical solution adopted by the utility model is as follows:

[0009] The utility model discloses a continuous desolventizing system, comprising a storage tank, a desolventizing kettle, a first distillation tower and an extraction receiver which are connected in sequence; wherein the desolventizing kettle is cyclically connected to a reboiler, and the desolventizing kettle is connected to a secondary separation component.

[0010] Furthermore, the secondary separation component comprises a distillation kettle, the material inlet of which is connected to the bottom of the desolventizing kettle via a pipeline, and the gas outlet of which is connected to the extraction receiver via a second distillation tower.

[0011] Furthermore, a condenser is provided between the first distillation tower and the extraction receiver, and between the second distillation tower and the extraction receiver.

[0012] Furthermore, a filter is provided in parallel on the connecting pipe between the storage tank and the desolventizing kettle.

[0013] Furthermore, liquid level sensors are provided in the desolventizing kettle, the extraction receiver and the distillation kettle.

[0014] Furthermore, a regulating valve and a delivery pump are provided on the connecting pipeline between the desolventizing kettle and the storage tank, the reboiler and the distillation kettle.

[0015] Furthermore, a stirrer is provided in the distillation kettle.

[0016] Furthermore, the extraction receiver is connected to a washing kettle.

[0017] 3. Beneficial effects

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] (1) A continuous desolventizing system of the utility model is connected to the desolventizing kettle and the reboiler through a circulation, so that the mixture to be desolventized enters the reboiler through the desolventizing kettle, and returns to the desolventizing kettle after being heated by the reboiler; the gas enters the extraction receiver after being processed by the first distillation tower, and the liquid remains in the desolventizing kettle, thereby completing the continuous desolventizing operation. At the same time, through the setting of the secondary separation component, the excess bottom material in the desolventizing kettle can be removed in time, on the one hand, it can prevent the occurrence of material rushing due to excessive bottom material; on the other hand, the bottom material can be subjected to secondary distillation to obtain another distillate, thereby realizing the continuous desolventizing operation of materials with different components.

[0020] (2) A continuous desolventizing system of the utility model can condense the separated components by providing condensers between the first distillation tower and the extraction receiver, and between the second distillation tower and the extraction receiver, so as to facilitate collection by the solvent extraction receiver.

[0021] (3) A continuous desolventizing system of the utility model is provided with a regulating valve between the desolventizing kettle and the storage tank, and cooperates with a liquid level sensor in the desolventizing kettle. The flow rate entering the desolventizing kettle is controlled by adjusting the opening size of the regulating valve, so that the extraction rate is consistent with the feed rate, which is conducive to the continuous desolventizing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The utility model is a structural principle diagram of a continuous desolventizing system.

[0023] In the figure: 1. Storage tank; 2. Desolventizing kettle; 3. First distillation tower; 4. Extraction receiver; 5. Reboiler; 6. Still; 7. Second distillation tower; 8. Filter; 9. Condenser; 10. Regulating valve; 11. Delivery pump; 12. Agitator. DETAILED DESCRIPTION

[0024] In order to further understand the content of the utility model, the utility model is described in detail in conjunction with the accompanying drawings.

[0025] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0026] The utility model is further described below in conjunction with specific embodiments.

[0027] like Figure 1 As shown, a continuous desolventizing system of this embodiment includes a storage tank 1, a desolventizing kettle 2, a first distillation tower 3 and an extraction receiver 4 which are connected in sequence. Among them, the desolventizing kettle 2 is circulated and connected with a reboiler 5, which is used to heat the material flowing out of the desolventizing kettle 2, so that the low-boiling point components are vaporized, and then returned to the desolventizing kettle 2, and after being processed by the first distillation tower 3, they enter the extraction receiver 4; while the distillation bottoms are some high-boiling point components, which continue to remain in the desolventizing kettle 2.

[0028] When there is too much distillation bottoms in the desolventizing kettle 2, part of the distillation bottoms will enter the extraction receiver 4 through the pipeline, which will not only cause waste, but also interfere with the components in the extraction receiver 4. For this reason, the desolventizing kettle 2 is also connected to a secondary separation component, which transfers the distillation bottoms in the desolventizing kettle 2 in time and performs distillation again to obtain another component solvent (distillate).

[0029] Specifically, the above-mentioned secondary separation component includes a still 6 and a second distillation tower 7. The material inlet of the still 6 is connected to the bottom of the desolventizing still 2 through a pipeline, and a regulating valve 10 and a delivery pump 11 are provided on the pipeline to facilitate the transportation and transfer of the distillation bottom material in the desolventizing still 2. Similarly, a regulating valve 10 and a delivery pump 11 are also required to be provided on the connecting pipelines between the desolventizing still 2 and the storage tank 1, and between the desolventizing still 2 and the reboiler 5. The gas outlet of the still 6 is connected to the second distillation tower 7, and the second distillation tower 7 is connected to the extraction receiver 4.

[0030] At the same time, a collecting tank can be connected to the bottom of the still 6 to collect the bottoms of the still 6. Of course, according to actual process requirements, the still 6 can also be connected to another secondary separation component to separate the bottoms in the still 6 again.

[0031] In order to ensure the uniformity of the mixing of the materials in the still 6 and improve the distillation effect, a stirrer 12 may be provided in the still 6, and the stirrer 12 may be any one of a paddle stirrer, a turbine stirrer, or a spiral stirrer. At the same time, in order to facilitate the monitoring of the liquid level in the still 6, a liquid level sensor (not shown in the figure), such as a radar level gauge, is also provided in the still 6. Of course, liquid level sensors may also be provided in the desolventizing still 2 and the extraction receiver 4 to monitor their respective liquid levels.

[0032] A continuous desolventizing system of this embodiment can be desolventized while feeding through the circulation connection between the desolventizing kettle 2 and the reboiler 5, thereby realizing continuous desolventizing operation. Through the setting of the secondary separation component, the excess bottoms in the desolventizing kettle 2 can be removed in time, which can prevent the phenomenon of excessive bottoms and continuous feeding exceeding the processing capacity of the equipment, thereby preventing the occurrence of material rush; on the other hand, the bottoms can be distilled twice to obtain another distillate, realizing continuous desolventizing operation of materials with different components.

[0033] In addition, the material is heated by an external reboiler 5. During the desolventizing process, the flow rate of the fluid in the reboiler 5 can be increased to improve the heat transfer coefficient and enhance the heat transfer effect. At the same time, the external reboiler 5 does not occupy the space in the kettle, does not affect the volume of the material in the desolventizing kettle 2, is simple and convenient to install and operate, and is easier to maintain.

[0034] In this embodiment, as a preferred implementation, a condenser 9 is provided between the first distillation tower 3 and the extraction receiver 4, and between the second distillation tower 7 and the extraction receiver 4. Through the provision of the condenser 9, the separated components can be condensed, so as to facilitate collection by the solvent extraction receiver 4. Of course, in order to ensure the condensation effect, a plurality of condensers 9 can be provided.

[0035] In addition, a filter 8 is provided on the connecting pipe between the storage tank 1 and the desolventizing kettle 2 to filter impurities in the mixed material. Preferably, the filter 8 is arranged in parallel and is opened and closed by a regulating valve 10. With such a design, when the filter 8 fails and needs to be repaired and replaced, the normal transportation of the material is not affected.

[0036] The utility model is a continuous desolventizing system, and its working process is as follows:

[0037] The mixture to be desolvated is filtered through the filter 8 from the storage tank 1 and then enters the desolvation kettle 2. When the liquid level in the desolvation kettle 2 reaches a certain position, the transfer pump 11 between the desolvation kettle 2 and the reboiler 5 is started to circulate the mixture between the desolvation kettle 2 and the reboiler 5. The mixture is heated by the reboiler 5, and the low-boiling point components are vaporized. The steam enters the first distillation tower 3, is condensed by the condenser 9 at the top, and finally enters the extraction receiver 4.

[0038] At the same time, by controlling the opening of the regulating valve 10 between the storage tank 1 and the desolventizing kettle 2, the material is continuously fed into the desolventizing kettle 2. When the liquid level in the desolventizing kettle 2 remains unchanged, the extraction rate is kept consistent with the feeding rate, and the purpose of continuous desolventizing can be achieved. As the amount of distillation bottoms increases, the liquid level in the desolventizing kettle 2 begins to rise. At this time, the secondary separation component is started. The distillation bottoms in the desolventizing kettle 2 are transferred to the distillation kettle 6, and then distilled again through the second distillation tower 7. The distillate is condensed in the condenser 9 and finally enters the extraction receiver 4. Finally, the components of the extraction receiver 4 are transported to the washing kettle (not shown in the figure) through a pipeline.

[0039] A continuous desolventizing system of the present embodiment can perform secondary separation on the mixture on the basis of realizing continuous desolventizing; at the same time, it can effectively eliminate the material rushing phenomenon caused by excessive distillation bottoms.

[0040] In addition, it should be noted that the bottoms in this embodiment are mainly flash concentrated liquid of benzene-alcohol mixture (toluene, aqueous methanol and by-products); the distillate is mainly distilled concentrated liquid of aqueous methanol, toluene and by-products.

[0041] The above schematically describes the present invention and its implementation methods, which are not restrictive. The drawings show only one implementation method of the present invention, and the actual structure is not limited thereto. Therefore, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A continuous desolventizing system, characterized in that: It comprises a storage tank (1), a desolventizing kettle (2), a first distillation tower (3) and an extraction receiver (4) which are connected in sequence; wherein the desolventizing kettle (2) is circulatedly connected to a reboiler (5), and the desolventizing kettle (2) is connected to a secondary separation component.

2. A continuous desolventizing system according to claim 1, characterized in that: The secondary separation component comprises a distillation kettle (6), the material inlet of which is connected to the bottom of the desolventizing kettle (2) through a pipeline, and the gas outlet of which is connected to the extraction receiver (4) through a second distillation tower (7).

3. A continuous desolventizing system according to claim 2, characterized in that: A condenser (9) is provided between the first distillation tower (3) and the extraction receiver (4), and between the second distillation tower (7) and the extraction receiver (4).

4. A continuous desolventizing system according to any one of claims 1 to 3, characterized in that: A filter (8) is arranged in parallel on the communication pipe between the storage tank (1) and the desolventizing kettle (2).

5. A continuous desolventizing system according to claim 2, characterized in that: The desolventizing kettle (2), the extraction receiver (4) and the distillation kettle (6) are all provided with liquid level sensors.

6. A continuous desolventizing system according to claim 5, characterized in that: A regulating valve (10) and a delivery pump (11) are provided on the connecting pipeline between the desolventizing kettle (2) and the material storage tank (1), the reboiler (5) and the distillation kettle (6).

7. A continuous desolventizing system according to claim 2, characterized in that: The distillation kettle (6) is provided with a stirrer (12).

8. A continuous desolventizing system according to claim 1, characterized in that: The extraction receiver (4) is connected to a washing kettle.

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