Acid bath filtering system and method for viscose staple fiber production

Abstract

The invention relates to an acid bath filtering system and method for viscose staple fiber production, the acid bath filtering system for viscose staple fiber production comprises an intermediate tank, an acid bath circulating barrel, a spinning machine, an acid bath head tank, a mixing barrel, a degassing mechanism, a tow filtering mechanism and a flash evaporation mechanism, the acid bath head tank is connected with the spinning machine through a pipeline and supplies acid bath liquid to the spinning machine; the spinning machine is connected with the degassing mechanism through a spinning acid return barrel by a pipeline and conveys reaction liquid to the degassing mechanism for degassing, the degassing mechanism is connected with the mixing barrel through a pipeline, the mixing barrel is connected with the acid bath circulating barrel through a pipeline, and the acid bath circulating barrel is connected with the tow filtering mechanism through a pipeline. The tow filtering mechanism is connected with the flash evaporation mechanism by a pipeline through a flash evaporation feeding barrel; the flash evaporation mechanism comprises flash evaporation equipment, a concentrated acid tank, a saltpeter extraction feeding barrel, saltpeter extraction equipment and a settling tank which are sequentially connected through pipelines, the settling tank is connected and communicated with the intermediate tank through a third acid falling pipeline, and the intermediate tank is connected and communicated with the tow filtering mechanism through a return pipe.

Description

Technical Field

[0001] This invention relates to the technical field of viscose staple fiber production, specifically to an acid bath filtration system and method for viscose staple fiber production. Background Technology

[0002] Acid baths are currently the most commonly used coagulation baths in viscose staple fiber production. The production process mainly involves the reaction between viscose and the acid bath. Viscose's main components are cellulose xanthate, alkali, and water. The reaction process involves the decomposition of cellulose xanthate and acid-base neutralization. During spinning, the acid bath reacts with the cellulose xanthate and xanthation byproducts in the viscose to generate a large amount of colloidal sulfur. Some of these colloidal sulfur particles are dispersed in the acid bath, while others form colloids that float on the surface. In addition, a large amount of impurities carried in the viscose, along with recycled wastewater, viscose lumps, and waste fibers, enter the acid bath, making it turbid. The presence of these impurities directly affects spinning performance and finished product quality, increasing spinning defects. The acid bath needs to remove solid impurities from the spinning process during preparation. Filtration removes these impurities from the acid bath during circulation. The filtration quality directly affects the quality of the finished yarn; therefore, improving filtration quality is essential.

[0003] The number of filters in the filtration system is determined based on the bath volume and filtration capacity of the production system. Simultaneously, filters with corresponding capacities are matched according to the acid supply capacity of the filtration acid supply pump. The traditional filtration system process is as follows: the spinning bath returns to the degassing return tank from the degassing mechanism; the acid is pumped by the filtration pump into the main distribution pipe and then into a single fiber bundle filter. The fiber bundle filter achieves filtration by having acid enter from the bottom and exit from the top. The acid from the single filter is collected in the return pipe and flows back to the filtration return tank. During backwashing of the fiber bundle filter, the waste acid flows back to the fiber bundle acid return tank, is filtered by the fiber bundle backwash pump through a plate and frame filter press, and then returns to the degassing return tank. After backwashing, the filter distributes acid normally, and the returned acid directly collects in the return pipe and flows back to the filtration return tank. Due to flash evaporation backwashing, pressure testing, and flash evaporation restarting after unplanned shutdowns, the acid from the nitrification equipment contains many impurities, which can easily form black spots if directly entering the spinning machine. If the acid from the flash evaporation nitrification equipment is connected via pipeline and directly returned to the filter pump's acid inlet pipe, and then distributed to the entire filter system through the main acid distribution pipe, the acid output from each filter will be collected and returned to the filter return tank via the return pipe. This will cause the filtration volume to be unstable. Direct pipeline connection will result in a smaller filtration volume and will also introduce air, which can easily lead to fluctuations in process parameters.

[0004] Therefore, using traditional filtration systems can lead to unstable filtration volume, low filtration quality, high workload for employees, and problems such as randomness and unpredictability. Summary of the Invention

[0005] In order to solve one or more technical problems existing in the prior art, the present invention provides an acid bath filtration system and method for viscose staple fiber production.

[0006] The technical solution of this invention to solve the above-mentioned technical problems is as follows: This invention provides an acid bath filtration system for viscose staple fiber production, including an intermediate tank, an acid bath circulation tank, a spinning machine, an acid bath high-level tank, a mixing tank, a degassing mechanism, a fiber tow filtration mechanism, and a flash evaporation mechanism. The acid bath high-level tank is connected to the spinning machine through a pipeline and supplies acid bath liquid to the spinning machine. The spinning machine is connected to the degassing mechanism through a spinning return acid tank via a pipeline and transports the reaction liquid to the degassing mechanism for degassing. The degassing mechanism is connected to the mixing tank through a pipeline. The mixing tank is connected to the acid bath circulation tank through a pipeline. The acid bath circulation tank is connected to the fiber tow filtration mechanism through a pipeline and transports the degassed reaction liquid to the fiber tow filtration mechanism for filtration. The fiber tow filtration mechanism is connected to the flash evaporation mechanism through a flash evaporation feed tank via a pipeline and transports the filtered reaction liquid to the flash evaporation mechanism for flash evaporation and nitration removal. The flash evaporation mechanism includes a flash evaporation device, a concentrated acid tank, a nitrate extraction feed tank, a nitrate extraction device, and a settling tank, which are connected in sequence via pipelines. The nitrate extraction feed tank is connected to the concentrated acid tank via a first acid bath pipeline. The concentrated acid tank is connected to the mixing tank via a second acid bath pipeline. The settling tank is connected to the intermediate tank via a third acid bath pipeline. The intermediate tank is connected to the fiber bundle filtration mechanism via a reflux pipe. A first valve is provided on the first acid bath pipeline, a second valve is provided on the third acid bath pipeline, and a third valve, an acid pump, and a fourth valve are sequentially provided on the reflux pipe. A fifth valve is provided between the acid bath circulation tank and the fiber bundle filtration mechanism.

[0007] The beneficial effects of this invention are as follows: The acid bath filtration system for viscose staple fiber production of this invention, based on the original filtration and flash nitration system, adds an intermediate tank and an acid pump. During unscheduled equipment shutdowns (such as backwashing, pressurization, and unplanned maintenance of the flash nitration system), it receives flash-evaporated acid, which is then filtered through a return pipe connected to the fiber bundle filtration mechanism. The filtered acid is then returned to the high-level acid bath for use by the spinning machine. This process is highly efficient, effectively improves filtration quality, and stabilizes the filtration volume. Furthermore, this invention achieves full filtration by setting up a mixing tank, meaning that all reaction solutions must be filtered before reuse.

[0008] Based on the above technical solution, the present invention can be further improved as follows.

[0009] Furthermore, the return pipe is connected to multiple branch pipes, each branch pipe is connected to at least one set of fiber bundle filter mechanisms, and each branch pipe is connected to a sixth valve.

[0010] The beneficial effect of adopting the above-mentioned further solution is that by setting multiple branch pipes on the reflux pipe, the fiber bundle filter mechanism connected to one of the branch pipes can be selected as needed to filter the acid in the intermediate tank without affecting the normal use of the fiber bundle filter mechanisms connected to other branch pipes.

[0011] Furthermore, each of the branch pipes is connected to multiple sets of filament filter mechanisms, which are connected in parallel on the branch pipe. Each set of filament filter mechanisms is also connected to and communicates with the acid bath circulation tank through an acid inlet pipe. The acid inlet pipe is equipped with an acid inlet pump and a fifth valve.

[0012] The beneficial effect of adopting the above-mentioned further solution is that by connecting multiple sets of filament filter mechanisms in parallel on each branch pipe, one or more sets of filament filter mechanisms can be selected for filtration according to the filtration volume requirements, which is convenient and reliable.

[0013] Furthermore, the fiber bundle filtration mechanism includes multiple filter lines, multiple output lines, and multiple fiber bundle filters. The acid bath circulation tank is connected to and communicates with the multiple filter lines through an acid inlet pipe. The multiple filter lines are sequentially connected in parallel through parallel pipelines and then connected to the multiple fiber bundle filters through multiple output lines. The number of filter lines is greater than the number of output lines. Each output line is connected to one fiber bundle filter. Each parallel pipeline is equipped with a seventh valve.

[0014] The beneficial effects of adopting the above-mentioned further solution are: by connecting multiple filter lines in parallel in sequence, the acid bath solution can be supplied to the fiber bundle filter in a unified manner, and the number of filter lines to be operated can be selected as needed to meet the filtration requirements.

[0015] Furthermore, each of the filter lines is equipped with a filter pump and an eighth valve, and at least one of the output lines is connected to a first string of acid connecting pipes.

[0016] Furthermore, the fiber filter is also connected to the acid bath circulation tank via a reflux pipeline, and a ninth valve is provided on the reflux pipeline.

[0017] The beneficial effects of adopting the above-mentioned further solution are as follows: the original fiber tow filtration mechanism receiving acid droplets can be changed to be able to switch between the mixing tank and the fiber tow filtration mechanism. When the fiber tow filter backwashing is started, by opening the ninth valve and closing the valve between the fiber tow filter and the flash feed tank, and closing the valve between the fiber tow filter and the acid bath high-level tank, the normal acid bath of the fiber tow filter can first drop acid into the acid bath circulation tank, remove the residual dirty acid in the pipeline, and then close the ninth valve to transfer the acid bath of the fiber tow filter into the flash feed tank and the acid bath high-level tank, and enter the normal process.

[0018] Furthermore, the fiber tow filter is connected to and communicates with the fiber tow acid return tank via a backwashing pipeline, and the fiber tow acid return tank is connected to the mixing tank via a plate and frame filter press.

[0019] Furthermore, the intermediate tank is connected to an acid bath recovery pipe and a second string of acid connection pipes. The intermediate tank is equipped with a level gauge; the flash feed tank is also connected to and communicates with the mixing tank via an overflow pipe; the spinning acid return tank is connected to and communicates with the mixing tank via an overflow pipe; and the settling tank is connected to and communicates with both the mixing tank and the concentrated acid tank via pipes.

[0020] Furthermore, the main outlet pipe of the fiber bundle filter of the filtration mechanism is also connected to and communicates with the acid bath high-level tank through a pipeline, the acid bath high-level tank is connected to and communicates with the spinning machine through a pipeline, and the acid bath high-level tank is also connected to and communicates with the spinning acid return tank through a high-level overflow pipeline.

[0021] This invention also provides an acid bath filtration method for viscose staple fiber production, which is implemented using an acid bath filtration system for viscose staple fiber production as described above, including the following steps: after an unconventional shutdown, during normal startup, first open the second valve on the third acid drop pipeline to allow the flash evaporation mechanism to drop acid through the third acid drop pipeline into the intermediate tank, then close the first valve on the first acid drop pipeline, open the third and fourth valves on the return pipe, and close the fifth valve between the acid bath circulation tank and the fiber tow filtration mechanism, so that the nitration equipment drops acid into the intermediate tank and transports it to the fiber tow filtration mechanism for filtration.

[0022] The beneficial effects of this invention are: Based on the original filtration system, this invention switches the pipeline to a separately isolated fiber bundle filtration mechanism, which is used alone for acid filtration after unconventional shutdowns and is not connected to other fiber bundle filters. This process is simple and feasible, has high working efficiency, effectively improves filtration quality, and stabilizes filtration volume. Attached Figure Description

[0023] Figure 1 This is a process flow diagram of the acid bath filtration system for viscose staple fiber production according to the present invention. Figure 2 This is a schematic diagram of the pipeline connection structure between the intermediate tank and the fiber bundle filtration mechanism of the present invention; Figure 3 This is a schematic diagram of the pipeline connection structure of the fiber bundle filtration mechanism of the present invention.

[0024] The attached diagram lists the components represented by each number as follows: 1. Intermediate tank; 11. Exhaust pipe; 12. Acid bath recovery pipe; 13. Second acid connection pipe; 14. Level gauge; 15. Acid pump; 16. Third acid drop pipe; 17. Return pipe; 18. Branch pipe; 19. Sixth valve; 190. Second valve; 191. Third valve; 192. Fourth valve; 2. Acid inlet pipe; 21. Acid inlet pump; 22. Fifth valve; 3. Fiber bundle filtration mechanism; 31. Filtration pipeline; 32. Output pipeline; 33. Parallel pipeline; 34. Seventh valve; 35. Filtration pump; 36. Eighth valve; 37. First acid connection pipe. Detailed Implementation

[0025] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0026] Example 1 like Figures 1-3 As shown in this embodiment, an acid bath filtration system for viscose staple fiber production includes an intermediate tank 1, an acid bath circulation tank, a spinning machine, an acid bath high-level tank, a mixing tank, a degassing mechanism, a fiber tow filtration mechanism 3, and a flash evaporation mechanism. The acid bath high-level tank is connected to the spinning machine via a pipeline and supplies acid bath liquid to the spinning machine. The spinning machine is connected to the degassing mechanism via a spinning return acid tank via a pipeline and transports the reaction liquid to the degassing mechanism for degassing. The degassing mechanism is connected to the mixing tank via a pipeline. The mixing tank is connected to the acid bath circulation tank via a pipeline. The acid bath circulation tank is connected to the fiber tow filtration mechanism 3 via a pipeline and transports the degassed reaction liquid to the fiber tow filtration mechanism 3 for filtration. The fiber tow filtration mechanism 3 is connected to the flash evaporation mechanism via a flash evaporation feed tank via a pipeline and transports the filtered reaction liquid to the flash evaporation mechanism for flash evaporation and nitration removal. Among them, such as Figure 1 and Figure 2 As shown, the flash evaporation mechanism in this embodiment includes a flash evaporation device, a concentrated acid tank, a nitrate extraction feed tank, a nitrate extraction device, and a settling tank connected in sequence via pipelines. The nitrate extraction feed tank is connected to and communicates with the concentrated acid tank via a first acid bath pipeline. The concentrated acid tank is connected to and communicates with the mixing tank via a second acid bath pipeline. The settling tank is connected to and communicates with the intermediate tank 1 via a third acid bath pipeline 16. The intermediate tank 1 is connected to and communicates with the fiber bundle filter mechanism 3 via a return pipe 17. A first valve is provided on the first acid bath pipeline. A second valve 190 is provided on the third acid bath pipeline 16. A third valve 191, an acid pump 15, and a fourth valve 192 are sequentially provided on the return pipe 17. A fifth valve 22 is provided between the acid bath circulation tank and the fiber bundle filter mechanism 3.

[0027] like Figure 2 As shown, in a preferred embodiment, the intermediate tank 1 is connected to an exhaust pipe 11, an acid bath recovery pipe 12, and a second acid connection pipe 13. More preferably, the intermediate tank 1 is equipped with a level gauge 14. The level gauge can also be electrically connected to an acid pump, which is also connected to a flow meter. By using the level gauge for the electrical connection to the acid pump, the liquid level in the intermediate tank and the acid distribution rate can be controlled.

[0028] Specifically, the flash feeding tank is connected to the mixing tank via an overflow pipe, the spinning acid return tank is connected to the mixing tank via an overflow pipe, and the settling tank is connected to the mixing tank and the concentrated acid tank via pipes.

[0029] like Figure 1 As shown, in a specific embodiment, the main acid return pipe of the fiber tow filter of the filtration mechanism is also connected to and communicates with the high-level acid bath tank via a pipeline. The high-level acid bath tank is connected to and communicates with the spinning machine via a pipeline. The high-level acid bath tank is also connected to and communicates with the spinning acid return tank via a high-level overflow pipeline. The fiber tow filter of the fiber tow filtration mechanism 3 is also connected to and communicates with the fiber tow acid return tank via a backwash pipeline. The fiber tow acid return tank is also connected to the mixing tank via a plate and frame filter press.

[0030] In this embodiment, the first valve, the second valve 190, the third valve 191, the fourth valve 192, and the fifth valve 22 are preferably butterfly valves.

[0031] The acid bath filtration system for viscose staple fiber production in this embodiment, based on the original filtration and flash nitrification system, adds an intermediate tank and an acid pump. When the equipment is shut down unexpectedly (such as during backwashing, pressurization, or unplanned maintenance of the flash nitrification system), it receives flash-evaporated acid, which is then filtered through a return pipe connected to the fiber bundle filtration mechanism. After filtration, the acid is returned to the flash evaporation mechanism for use by the spinning machine. This process has high efficiency, effectively improves filtration quality, and stabilizes the filtration volume.

[0032] Example 2 Based on Embodiment 1, this embodiment provides a preferred arrangement of the filament filter mechanism. For example... Figure 2 As shown, the return pipe 17 is connected to multiple branch pipes 18, each branch pipe 18 is connected to at least one set of fiber bundle filter mechanisms 3, and each branch pipe 18 is connected to a sixth valve 19. The sixth valve 19 is preferably a butterfly valve. By setting multiple branch pipes on the return pipe, the fiber bundle filter mechanism connected to one of the branch pipes can be selected as needed to filter the acid in the intermediate tank without affecting the normal use of the fiber bundle filter mechanisms connected to other branch pipes.

[0033] Example 3 Based on Embodiment 2, in this embodiment, each branch pipe 18 is connected to multiple sets of filament filter mechanisms 3. These multiple sets of filament filter mechanisms 3 are connected in parallel on their respective branch pipes 18. Each set of filament filter mechanisms 3 is also connected and communicates with the acid bath circulation tank via an acid inlet pipe 2. The acid inlet pipe 2 is equipped with an acid inlet pump 21 and a fifth valve 22. By connecting multiple sets of filament filter mechanisms in parallel on each branch pipe, one or more sets of filament filter mechanisms can be selected for filtration according to the required filtration volume, making it convenient and reliable.

[0034] Example 4 Based on Embodiment 3, the fiber bundle filtration mechanism in this embodiment includes multiple filter lines 31, multiple output lines 32, and multiple fiber bundle filters. The acid bath circulation tank is connected to and communicates with the multiple filter lines 31 via acid inlet pipes 2. The multiple filter lines 31 are sequentially connected in parallel via parallel pipes 33 and then connected to the multiple fiber bundle filters via multiple output lines 32. The number of filter lines 31 is greater than the number of output lines 32. Each output line 32 is connected to one fiber bundle filter. Each parallel pipe 33 is equipped with a seventh valve 34. Preferably, the seventh valve 34 is a butterfly valve. By sequentially connecting multiple filter lines in parallel, the acid bath solution can be supplied to the fiber bundle filters in a unified manner. The number of filter lines to be operated can be selected as needed to meet filtration requirements.

[0035] Specifically, each of the filter lines 31 is equipped with a filter pump 35 and an eighth valve 36, and at least one of the output lines 32 is connected to a first series of acid connection pipes 37. The eighth valve 36 is preferably a butterfly valve.

[0036] Preferably, the fiber tow filter is also connected to the acid bath circulation tank via a backflow pipeline, and a ninth valve is provided on the backflow pipeline. The original fiber tow filter mechanism receiving fallen acid is modified to allow switching between the mixing tank and the fiber tow filter mechanism. When the fiber tow filter backwashing is started, by opening the ninth valve and closing the valve between the fiber tow filter and the flash feed tank, and closing the valve between the fiber tow filter and the acid bath high-level tank, the normal acid bath from the fiber tow filter can first fall into the acid bath circulation tank to remove residual dirty acid from the pipeline. After this, the ninth valve is closed, and the acid bath from the fiber tow filter is transferred to the flash feed tank and the acid bath high-level tank for normal operation.

[0037] Example 5 This embodiment provides an acid bath filtration method for viscose staple fiber production, implemented using an acid bath filtration system for viscose staple fiber production as described above. The method includes the following steps: After an unconventional shutdown, during normal startup, first open the second valve 190 on the third acid stripping pipeline 16 to allow the flash evaporation mechanism to drop acid through the third acid stripping pipeline 16 into the intermediate tank 1. Then close the first valve on the first acid stripping pipeline, open the third valve 191 and the fourth valve 192 on the return pipe, and close the fifth valve 22 between the acid bath circulation tank and the fiber tow filtration mechanism 3, allowing the acid from the nitrification equipment to drop acid into the intermediate tank 1 and be transported to the fiber tow filtration mechanism 3 for filtration.

[0038] Based on the original filtration system, this embodiment switches the pipeline to a separately isolated fiber bundle filtration mechanism, which is used exclusively for acid filtration after unconventional shutdowns. It is not connected to other fiber bundle filters. This process is simple and feasible, has high working efficiency, effectively improves filtration quality, and stabilizes filtration volume.

[0039] In the description of this invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0040] Furthermore, the terms "first," "second," "third," "fourth," "fifth," "sixth," "seventh," and "eighth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0041] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0043] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0044] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An acid bath filtration system for viscose staple fiber production, characterized in that, The system includes an intermediate tank, an acid bath circulation tank, a spinning machine, an acid bath high-level tank, a mixing tank, a degassing mechanism, a fiber bundle filtration mechanism, and a flash evaporation mechanism. The acid bath high-level tank is connected to the spinning machine via a pipeline and supplies acid bath liquid to the spinning machine. The spinning machine is connected to the degassing mechanism via a spinning acid return tank via a pipeline and transports the reaction liquid to the degassing mechanism for degassing. The degassing mechanism is connected to the mixing tank via a pipeline. The mixing tank is connected to the acid bath circulation tank via a pipeline. The acid bath circulation tank is connected to the fiber bundle filtration mechanism via a pipeline and transports the degassed reaction liquid to the fiber bundle filtration mechanism for filtration. The fiber bundle filtration mechanism is connected to the flash evaporation mechanism via a flash evaporation feed tank via a pipeline and transports the filtered reaction liquid to the flash evaporation mechanism for flash evaporation and nitration extraction. The flash evaporation mechanism includes a flash evaporation device, a concentrated acid tank, a nitrate extraction feed tank, a nitrate extraction device, and a settling tank, which are connected in sequence via pipelines. The nitrate extraction feed tank is connected to the concentrated acid tank via a first acid bath pipeline. The concentrated acid tank is connected to the mixing tank via a second acid bath pipeline. The settling tank is connected to the intermediate tank via a third acid bath pipeline. The intermediate tank is connected to the fiber bundle filtration mechanism via a reflux pipe. A first valve is provided on the first acid bath pipeline, a second valve is provided on the third acid bath pipeline, and a third valve, an acid pump, and a fourth valve are sequentially provided on the reflux pipe. A fifth valve is provided between the acid bath circulation tank and the fiber bundle filtration mechanism.

2. The acid bath filtration system for viscose staple fiber production according to claim 1, characterized in that, The return pipe is connected to multiple branch pipes, each branch pipe is connected to at least one set of fiber bundle filter mechanism, and each branch pipe is connected to a sixth valve.

3. The acid bath filtration system for viscose staple fiber production according to claim 2, characterized in that, Each of the branch pipes is connected to multiple sets of filament filter mechanisms, which are connected in parallel on the branch pipe. Each set of filament filter mechanisms is also connected to and communicates with the acid bath circulation tank through an acid inlet pipe. The acid inlet pipe is equipped with an acid inlet pump and a fifth valve.

4. The acid bath filtration system for viscose staple fiber production according to claim 3, characterized in that, The fiber bundle filtration mechanism includes multiple filter lines, multiple output lines, and multiple fiber bundle filters. The acid bath circulation tank is connected to and communicates with the multiple filter lines through an acid inlet pipe. The multiple filter lines are sequentially connected in parallel through parallel pipelines and then connected to multiple fiber bundle filters through multiple output lines. The number of filter lines is greater than the number of output lines. Each output line is connected to one fiber bundle filter. Each parallel pipeline is equipped with a seventh valve.

5. The acid bath filtration system for viscose staple fiber production according to claim 4, characterized in that, Each of the filter lines is equipped with a filter pump and an eighth valve, and at least one of the output lines is connected to a first string of acid connecting pipes.

6. The acid bath filtration system for viscose staple fiber production according to claim 4, characterized in that, The fiber filter is also connected to the acid bath circulation tank via a reflux pipeline, and a ninth valve is provided on the reflux pipeline.

7. The acid bath filtration system for viscose staple fiber production according to claim 4, characterized in that, The fiber bundle filter is also connected to the fiber bundle acid return tank via a backwashing pipeline, and the fiber bundle acid return tank is also connected to the mixing tank via a plate and frame filter press via a pipeline.

8. The acid bath filtration system for viscose staple fiber production according to claim 1, characterized in that, The intermediate tank is connected to an acid bath recovery pipe and a second acid connection pipe; the intermediate tank is equipped with a level gauge; the flash feed tank is also connected to the mixing tank through an overflow pipe; the spinning acid return tank is connected to the mixing tank through an overflow pipe; and the settling tank is connected to the mixing tank and the concentrated acid tank through pipes.

9. The acid bath filtration system for viscose staple fiber production according to claim 1, characterized in that, The main outlet pipe of the fiber bundle filter of the filtration mechanism is also connected to and communicates with the acid bath high-level tank through a pipeline. The acid bath high-level tank is connected to and communicates with the spinning machine through a pipeline. The acid bath high-level tank is also connected to and communicates with the spinning acid return tank through a high-level overflow pipeline.

10. An acid bath filtration method for viscose staple fiber production, characterized in that, The method employs an acid bath filtration system for viscose staple fiber production as described in any one of claims 1 to 9, comprising the following steps: after an unconventional shutdown, during normal startup, first open the second valve on the third acid removal pipeline to allow the flash evaporation mechanism to remove acid through the third acid removal pipeline into the intermediate tank, then close the first valve on the first acid removal pipeline, open the third and fourth valves on the return pipe, and close the fifth valve between the acid bath circulation tank and the fiber tow filtration mechanism to allow the nitrification equipment to remove acid into the intermediate tank and transport it to the fiber tow filtration mechanism for filtration.

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