Recovery device of dimethyl sulfoxide in PAN-based carbon fiber production

Abstract

The invention discloses a dimethyl sulfoxide recovery device in PAN-based carbon fiber production, which comprises a plurality of recovery towers which are sequentially connected in series; an alkali liquor supply system, the alkali liquor supply system comprises an alkali liquor storage tank, an alkali liquor supply main line led out from the alkali liquor storage tank, alkali liquor supply branch lines led out from the alkali liquor supply main line and respectively connected to a plurality of recovery towers, an alkali liquor supply pump arranged on the alkali liquor supply main line, and alkali liquor flow meters arranged on the alkali liquor supply branch lines and used for detecting the amount of alkali liquor supplied to the recovery towers; the bypass is established outside each recovery tower, a bypass pump is arranged on each bypass, and the bypass pumps are used for enabling the fluid in the recovery towers to flow into the recovery towers again after passing through the bypasses; the boilers are arranged on the bypasses of the recovery towers and used for boiling fluid flowing through the bypasses; and the rear PH value meter is used for detecting the PH value of the fluid corresponding to each recovery tower.

Description

Technical Field

[0001] The invention relates to a device for recovering dimethyl sulfoxide in the production of PAN-based carbon fibers. Background Art

[0002] In the prior art, a dimethyl sulfoxide recovery device in the production of PAN-based carbon fibers generally utilizes a recovery tower to wash and dehydrate a fluid containing dimethyl sulfoxide to obtain relatively pure dimethyl sulfoxide.

[0003] There are two key steps in the recovery of dimethyl sulfoxide.

[0004] The first key process: It is necessary to control the pH value of the reaction environment of dimethyl sulfoxide. To this end, in the prior art, alkali solution is introduced into the recovery tower to neutralize the acidic environment. However, in the prior art, the pH is controlled only by adding alkali solution to one recovery tower, which makes it difficult to accurately control the pH.

[0005] The second key process: A bypass is built outside the recovery tower, and a boiler is installed on the bypass, so that the fluid in the recovery tower passes through the boiler through the pump. During the process of passing through the boiler, the boiler boils the fluid, thereby separating the water vapor, thereby achieving the purpose of dehydration to a certain extent. However, the boiling effect of the boiler in the prior art is not good and the operating efficiency is not high. Summary of the invention

[0006] In view of the above technical problems existing in the prior art, an embodiment of the present invention provides a device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber.

[0007] In order to solve the above technical problems, the technical solution adopted in the embodiments of the present invention is: A device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber, comprising: A recovery tower, comprising a plurality of recovery towers, wherein the plurality of recovery towers are sequentially connected in series, and the fluid to be treated sequentially passes through the plurality of recovery towers in series; An alkali solution supply system, comprising an alkali solution storage tank, an alkali solution supply bus led out from the alkali solution storage tank, alkali solution supply branches led out from the alkali solution supply bus and connected to a plurality of recovery towers respectively, an alkali solution supply pump arranged on the alkali solution supply bus, and an alkali solution flow meter arranged on each of the alkali solution supply branches for detecting the amount of alkali solution supplied to the recovery tower; A bypass is built outside each recovery tower, and a bypass pump is arranged on the bypass, and the bypass pump is used to make the fluid in the recovery tower flow into the recovery tower again after passing through the bypass; a boiler disposed on a bypass of each recovery tower to boil the fluid flowing through the bypass; The post-mounted pH meter is used to detect the pH value of the fluid corresponding to each recovery tower.

[0008] Preferably, A compensation branch line is drawn out from the alkali solution supply branch line corresponding to the most downstream recovery tower, and the compensation branch line is connected to the boiler corresponding to the most downstream recovery tower.

[0009] Preferably, a pre-pH meter and an incoming flow meter are arranged on the incoming pipeline supplying the most upstream recovery tower.

[0010] Preferably, the boiler comprises: A shell, which is configured in a cylindrical shape, wherein an inlet is configured at the bottom of the shell, and an outlet is configured at the top of the shell, and the fluid from the recovery tower enters the shell from the inlet and flows out from the outlet to flow into the recovery tower; The boiling body comprises a plurality of heating tubes with different diameters which are stacked in sequence, and two adjacent heating tubes define an annular fluid channel, and the fluid entering the shell passes through the defined multiple annular fluid channels; a heating wire is embedded in the inner wall of each heating tube, and the heating wire covers the inner wall of the heater, so as to heat the fluid flowing through the annular fluid channel to make the fluid boil.

[0011] Preferably, From the radial outside to the radial inside, the plurality of heating tubes are sequentially offset in the axial direction by a preset distance, so that the lower ends of the plurality of heating tubes form a tapered fluid inlet area and the upper ends of the plurality of heating tubes form a tapered fluid outlet area.

[0012] Preferably, the cylinder wall of each heating cylinder is covered with balancing holes, and the balancing holes are used to allow the fluids in adjacent annular fluid channels to flow to each other.

[0013] Preferably, a conical disc seat made of mesh is provided at the lower end of each of the plurality of heating cylinders.

[0014] Preferably, an inner plate and a top plate are sequentially arranged on the top of the shell, the inner plate and the top plate define a cavity, the inner plate is covered with through holes, and the outlet of the shell is formed on the top plate.

[0015] Preferably, an alkaline solution inlet is arranged at the bottom of the housing.

[0016] Compared with the prior art, the beneficial effects of the dimethyl sulfoxide recovery device in the production of PAN-based carbon fiber disclosed in the present invention are: 1. In the recovery device, alkali solution is added to the first recovery tower, the second recovery tower and the third recovery tower respectively, so as to gradually adjust the pH value of the fluid so that the pH value of the fluid in the third recovery tower reaches the preset requirement, which is beneficial to the recovery effect and recovery efficiency. Preferably, the adjustment range of the pH value in the second recovery tower is greater than that in the first recovery tower and the third recovery tower.

[0017] 2. In the boiler, the stacked heating tubes are used to define a large number of annular fluid channels, thereby greatly increasing the heating area through which the fluid passes, thereby improving the boiling effect and boiling efficiency.

[0018] This summary of various implementations or examples of the technology described in this disclosure is not a comprehensive disclosure of the entire scope or all features of the disclosed technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar parts. The accompanying drawings generally illustrate various embodiments by way of example and not limitation, and together with the specification and claims, are used to illustrate the embodiments of the invention. When appropriate, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be exhaustive or exclusive embodiments of the present apparatus or method.

[0020] Figure 1 The present invention is a schematic structural diagram of a device for recovering dimethyl sulfoxide in the production of PAN-based carbon fibers provided in an embodiment of the present invention.

[0021] Figure 2 This is a main cross-sectional view of the boiler provided by the present invention.

[0022] Figure 3 Schematic diagram of the unfolded state of the heating cylinder in the boiler.

[0023] Reference numerals

[0024] 11-first recovery tower; 12-second recovery tower; 13-third recovery tower; 14-incoming pipeline; 141-front pH meter; 142-incoming flow meter; 15-discharging pipeline; 161-first discharging pump; 162-second discharging pump; 163-third discharging pump; 20-alkali solution supply main line; 21-first alkali solution supply branch line; 22-second alkali solution supply branch line; 23-third alkali solution supply branch line; 24-alkali solution storage tank; 25-alkali solution supply pump; 26-alkali solution flow rate meter; 27-compensation branch line; 28-compensation flowmeter; 30-boiler; 31-shell; 32-bottom cover; 321-inlet; 322-alkali solution inlet; 33-top plate; 331-outlet; 332-chamber; 34-inner plate; 341-through hole; 35-heating cylinder; 351-balance hole; 352-annular fluid channel; 353-fluid entry area; 354-electric heating wire; 36-conical disc seat; 40-bypass; 41-rear pH meter; 42-bypass pump. DETAILED DESCRIPTION

[0025] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0026] In order to keep the following description of the embodiments of the present invention clear and concise, detailed descriptions of well-known functions and well-known components are omitted.

[0027] like Figure 1 As shown, an embodiment of the present invention discloses a recovery device for dimethyl sulfoxide in the production of PAN-based carbon fiber, and the recovery device includes: an incoming material pipeline 14, a recovery tower, and an alkali solution supply system.

[0028] The recovery tower includes three recovery towers connected in series, i.e., a first recovery tower 11, a second recovery tower 12, and a third recovery tower 13 are connected in series in sequence through a discharge pipeline 15 led out from a discharge port, and a discharge pump is provided on the discharge pipeline 15 of each recovery tower, i.e., the first recovery tower 11 is correspondingly provided with a first discharge pump 161, the second recovery tower 12 is correspondingly provided with a second discharge pump 162, and the third recovery tower 13 is correspondingly provided with a third discharge pump 163, so that the fluid flowing out of the first recovery tower 11 flows to the second recovery tower 12, the fluid flowing out of the second recovery tower 12 flows to the third recovery tower 13, and the fluid flowing out of the third recovery tower 13 (treated dimethyl sulfoxide) flows to the storage equipment.

[0029] The incoming pipeline 14 is used to connect to the first recovery tower 11. The incoming pipeline 14 is used to provide a fluid containing dimethyl sulfoxide to the first recovery tower 11. Subsequently, relatively pure dimethyl sulfoxide is obtained by removing impurities through three recovery towers. A front pH meter 141 and an incoming flow meter 142 are installed on the incoming pipeline 14 to detect the pH value and volume of the fluid material entering the recovery tower.

[0030] The alkali solution supply system includes: an alkali solution storage tank 24, an alkali solution supply bus 20 led out from the alkali solution storage tank 24, a first alkali solution supply branch line 21, a second alkali solution supply branch line 22 and a third alkali solution supply branch line 23 led out from the alkali solution supply bus 20 and connected to the first recovery tower 11, the second recovery tower 12 and the third recovery tower 13 respectively, and an alkali solution supply pump 25 arranged on the alkali solution supply bus 20 for supplying the alkali solution storage tank 24 to the first recovery tower 11, the second recovery tower 12 and the third recovery tower 13 respectively through the three alkali solution supply branches, and an alkali solution flow meter 26 is arranged on each alkali solution supply branch line, and the alkali solution flow meter 26 is used to measure the amount of alkali solution supplied to each recovery tower.

[0031] A bypass 40 is constructed outside each recovery tower, and the bypass 40 is led out from the recovery tower and enters the recovery tower again. A bypass pump 42, a post-pH meter 41 and a boiler 30 are installed in sequence on each bypass 40. The fluid (containing dimethyl sulfoxide) from the recovery tower passes through the post-pH meter 41 and the boiler 30 in sequence through the bypass pump 42. The post-pH meter 41 is used to detect the pH value of the fluid, and the boiler 30 is used to boil the fluid and thereby make the water in the fluid form water vapor to achieve dehydration.

[0032] In the present invention, alkali solution is added to the first recovery tower 11, the second recovery tower 12 and the third recovery tower 13 respectively, so as to gradually adjust the pH value of the fluid so that the pH value of the fluid in the third recovery tower 13 reaches the preset requirement, which is beneficial to the recovery effect and recovery efficiency. Preferably, the adjustment range of the pH value in the second recovery tower 12 is greater than that in the first recovery tower 11 and the third recovery tower 13.

[0033] In a preferred embodiment of the present invention, a compensation branch line 27 is drawn out from the third alkali solution supply branch line 23, and the compensation branch line 27 is connected to the boiler 30. A compensation flowmeter 28 is provided on the compensation branch line 27. The compensation branch line 27 is used to supply alkali solution to the boiler 30, and supply the alkali solution to the boiler 30 at a smaller flow rate for fine-tuning the pH value of the fluid, thereby accurately controlling the pH value of the fluid in the third recovery tower 13.

[0034] The present invention provides a boiler 30 with a specific structure, which has a better boiling effect and boiling efficiency. Figure 2 and 3 Combined with Figure 1 As shown, the boiler 30 includes: a shell 31 and a boiling body arranged in the shell 31. Specifically, the shell 31 is a cylindrical structure, and a bottom cover 32 is arranged at the lower end of the shell 31, and an inlet 321 is arranged on the bottom cover 32, and an alkali liquid inlet 322 for connecting with the compensation branch line 27 is arranged on the bottom cover 32 of the boiler 30 installed on the bypass 40 of the third recovery tower 13, and an inner plate 34 and a top plate 33 are arranged at the upper end of the shell 31 in sequence, and the inner plate 34 is covered with through holes 341, and a cavity 332 is defined between the inner wall and the top plate 33, and the top plate 33 is arranged with an outlet 331, and the fluid in the bypass 40 enters the shell 31 through the inlet 321, and enters the cavity 332 through the through holes 341 of the inner plate 34, and then flows from the outlet 331 of the top plate 33 and then flows into the fluid recovery tower again.

[0035] The boiling body includes a plurality of heating tubes 35, the diameters of the plurality of heating tubes 35 are different, and the plurality of heating tubes 35 are stacked, so that an annular fluid channel 352 is defined between two adjacent heating tubes 35, and an electric heating wire 354 is embedded on the inner wall of each heating tube 35, and the electric heating wire 354 covers the inner wall of the heating tube 35, and the fluid entering the housing 31 enters the annular fluid channel 352 from the lower ports of the plurality of annular fluid channels 352, and flows upward along the annular fluid channel 352, and in the process of flowing along the annular fluid channel 352, the electric heating wire 354 heats the fluid, so that the fluid boils, and the heated and boiling fluid flows out from the upper port of the annular fluid channel 352, and flows into the cavity 332 through the through hole 341 of the inner plate 34, and then flows out from the outlet 331 of the top plate 33 and flows into the recovery tower again. The stacked heating tubes 35 define a plurality of annular fluid channels 352, thereby greatly increasing the heating area through which the fluid passes, thereby improving the boiling effect and boiling efficiency.

[0036] In some more preferred structures, from the radial outer side to the radial inner side, the plurality of heating tubes 35 are sequentially displaced by a preset distance in the axial direction, so that the lower ends of the plurality of heating tubes 35 form a tapered fluid inlet area 353 and the upper ends of the plurality of heating tubes 35 form a tapered fluid outlet area; the lower ends of the plurality of heating tubes 35 are provided with a tapered disc seat 36 made of a mesh. The lower ends and upper ends of the plurality of heating tubes 35 are sequentially displaced, which can not only effectively prevent the ports of the annular fluid channel 352 from being blocked, but more importantly, increases the area of ​​the lower ports of all the annular fluid channels 352, thereby allowing a larger flow of fluid to enter the annular fluid channel 352 at the same time. In addition, the mesh of the tapered disc seat 36 can intercept impurities in the fluid, thereby avoiding blocking the annular fluid channel 352.

[0037] In some more preferred structures, the wall of each heating tube 35 is covered with balancing holes 351, and the balancing holes 351 are used to allow the fluids in adjacent annular fluid channels 352 to flow to each other. In this way, the pressure in the annular fluid channels 352 between different heating tubes 35 can be balanced through the balancing holes 351 that allow the fluid to pass through the holes 341, thereby avoiding excessive pressure in a certain annular fluid channel 352 due to unbalanced heating.

[0038] In addition, although exemplary embodiments have been described in the present invention, the scope includes any and all embodiments based on the present invention with equivalent elements, modifications, omissions, combinations (e.g., various embodiments intersecting schemes), adaptations or changes. The elements in the claims will be interpreted broadly based on the language adopted in the claims, and are not limited to the examples described in this specification or during the execution of this application, and the examples will be interpreted as non-exclusive. Therefore, this specification and examples are intended to be considered as examples only, and the true scope and spirit are indicated by the following claims and the full scope of their equivalents.

[0039] The above description is intended to be illustrative rather than restrictive. For example, the above examples (or one or more schemes thereof) may be used in combination with each other. For example, a person of ordinary skill in the art may use other embodiments when reading the above description. In addition, in the above-mentioned specific embodiments, various features may be grouped together to simplify the present invention. This should not be interpreted as an intention that a disclosed feature that is not required to be protected is necessary for any claim. On the contrary, the subject matter of the present invention may be less than all the features of a particular disclosed embodiment. Thus, the following claims are incorporated herein as examples or embodiments in the specific embodiments, wherein each claim is independently a separate embodiment, and it is considered that these embodiments can be combined with each other in various combinations or arrangements. The scope of the present invention should be determined with reference to the appended claims and the full scope of equivalent forms granted by these claims.

[0040] The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present invention.

Claims

1. A device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber, characterized in that: include: A recovery tower, comprising a plurality of recovery towers, wherein the plurality of recovery towers are sequentially connected in series, and the fluid to be treated sequentially passes through the plurality of recovery towers in series; An alkali solution supply system, comprising an alkali solution storage tank, an alkali solution supply bus led out from the alkali solution storage tank, alkali solution supply branches led out from the alkali solution supply bus and connected to a plurality of recovery towers respectively, an alkali solution supply pump arranged on the alkali solution supply bus, and an alkali solution flow meter arranged on each of the alkali solution supply branches for detecting the amount of alkali solution supplied to the recovery tower; A bypass is built outside each recovery tower, and a bypass pump is arranged on the bypass, and the bypass pump is used to make the fluid in the recovery tower flow into the recovery tower again after passing through the bypass; a boiler disposed on a bypass of each recovery tower to boil the fluid flowing through the bypass; The post-mounted pH meter is used to detect the pH value of the fluid corresponding to each recovery tower.

2. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 1, characterized in that: A compensation branch line is drawn out from the alkali solution supply branch line corresponding to the most downstream recovery tower, and the compensation branch line is connected to the boiler corresponding to the most downstream recovery tower.

3. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 1, characterized in that: A pre-pH meter and an incoming flow meter are arranged on the incoming pipeline to the upstream recovery tower.

4. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 1, characterized in that: The boiler comprises: A shell, which is configured in a cylindrical shape, wherein an inlet is configured at the bottom of the shell, and an outlet is configured at the top of the shell, and the fluid from the recovery tower enters the shell from the inlet and flows out from the outlet to flow into the recovery tower; The boiling body comprises a plurality of heating tubes with different diameters which are stacked in sequence, and two adjacent heating tubes define an annular fluid channel, and the fluid entering the shell passes through the defined multiple annular fluid channels; a heating wire is embedded in the inner wall of each heating tube, and the heating wire covers the inner wall of the heater, so as to heat the fluid flowing through the annular fluid channel to make the fluid boil.

5. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 4, characterized in that: From the radial outside to the radial inside, the plurality of heating tubes are sequentially offset in the axial direction by a preset distance, so that the lower ends of the plurality of heating tubes form a tapered fluid inlet area and the upper ends of the plurality of heating tubes form a tapered fluid outlet area.

6. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 5, characterized in that: The cylinder wall of each heating cylinder is covered with balancing holes, and the balancing holes are used to allow the fluids in adjacent annular fluid channels to flow to each other.

7. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 5, characterized in that: The lower ends of the plurality of heating cylinders are provided with conical disc seats made of mesh.

8. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 5, characterized in that: An inner plate and a top plate are sequentially arranged on the top of the shell, the inner plate and the top plate define a cavity, the inner plate is covered with through holes, and the outlet of the shell is formed on the top plate.

9. The device for recovering dimethyl sulfoxide in the production of PAN-based carbon fiber according to claim 5, characterized in that: The bottom of the shell is provided with an alkaline solution inlet.

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