Acid bath circulation system and method in viscose staple fiber production process

Abstract

The application provides an acid bath circulating system and method in a viscose staple fiber production process. The acid bath circulating system in the viscose staple fiber production process comprises a circulating main pipe, a filter pump, a filter system, a high-level tank and an acid distribution package. The filter pump is connected with the circulating main pipe through a pipeline. The filter system is connected with the filter pump through a pipeline. The high-level tank is connected with the filter system through a pipeline. The acid distribution package is connected with the high-level tank through a high-level overflow pipe. The acid bath enters the high-level tank through the filter system. The acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. The acid bath is used for spinning and drawing after the flow is adjusted by the acid distribution package. The process is simple and feasible, and the work efficiency is high. The overflow of the high-level tank is used for spinning and drawing. The spinning pump is completely cancelled, and the power consumption is reduced. The acid bath used for spinning and drawing has been filtered by the filter system to remove impurities, so that the product quality is not affected by the impurities in the acid bath.

Description

Technical Field

[0001] This invention relates to the field of viscose staple fiber production technology, and in particular to an acid bath circulation system and method in the viscose staple fiber production process. Background Technology

[0002] Acid bath is currently the most commonly used coagulation bath in viscose staple fiber production. The production process mainly involves the reaction between viscose and the acid bath. The main components of viscose are cellulose xanthate, alkali, and water. The reaction process involves the decomposition of cellulose xanthate and acid-base neutralization. The main and side reactions generate a large amount of water, which dissolves in the acid bath. The acid bath can be recycled through preparation. The acid returned from spinning enters the degassing tank and is pumped into the degassing system. After degassing, the acid returns to the degassing reflux tank. The high-level overflow from the degassing reflux tank enters the main circulation pipe. The filter pump draws in the acid bath from here, and the acid returns to the filter reflux tank through the fiber bundle filter. Most of the acid overflows from the high-level overflow from the filter reflux tank into the mixing tank, where concentrated sulfuric acid and zinc sulfate solution are added. After thorough mixing, the high-level overflow from the mixing tank enters the main circulation pipe. After thorough mixing and preparation in the bottom tank, the solution is supplied to the spinning workshop by the spinning pump. During the preparation of the acid bath, water needs to be removed and excess sodium sulfate needs to be extracted. The purpose of flash evaporation is to remove the water introduced during spinning under vacuum by evaporation. The traditional flash evaporation process is approximately 170m. 3 The acid bath, with a flow rate of [amount missing] / h, enters evaporation chamber No. 10 via a flow meter. In this chamber and the next stage, evaporator No. 11, it is cooled to approximately 39°C. The acid bath then enters the magma circulation pump from evaporation chamber No. 11, and is subsequently pumped into preheaters No. 8 through No. 0. Finally, it passes through a heater, and through these stages of heating, the bath temperature rises to 107°C (maximum). The spinning bath enters the flash chambers (No. 1 to No. 9) from the heater and is cooled. After staged cooling, it finally reaches the required temperature and falls into the concentrated acid tank through evaporation chamber No. 9. From there, it flows directly into the main circulation pipe via the high-level overflow pipe of the concentrated acid tank. The one-step nitration process increases the concentration of the circulating acid bath, saturating the sodium sulfate and causing it to crystallize. The sodium sulfate grows in the crystallizer and deposits at the bottom, flowing into a settling tank. A settling pump then pumps the solid sodium sulfate particles into a vacuum belt filter to separate them. One-step nitrification processes currently include: 11-effect, 14-effect, and 16-effect one-step nitrification. Taking the 11-effect one-step nitrification process as an example, the process flow is as follows: approximately 50-60m 3 Acid bath of [amount] m³ / h enters evaporator No. 11 from the nitrate feed pump. From evaporator No. 11, the acid bath enters the circulation pump. There is a back-suction valve between the settling tank and evaporator No. 11, from which saturated acid bath is replenished to the system (after back-suction, the circulation rate is controlled at 160-170 m³ / h). 3The solution is pumped into preheaters 8-1 by a circulating pump, and finally passes through a heater. Through these stages of heating, the bath temperature reaches a maximum of 107℃. The spinning bath then enters the evaporators (1-11) for evaporation. The acid temperature of evaporator 10 is 50℃, and the vacuum level is adjusted using the evaporator 10's self-control valve to control the acid temperature. Under these conditions, sodium sulfate solid particles precipitate and enter a settling tank. The high-level overflow from the settling tank flows into the concentrated acid tank, while the low-level crystallized salt slurry is pumped by a settling pump into a nitrate suspension collector and fed into a vacuum belt filter for separation. The separated sodium sulfate enters a melting tank, is mixed with alkali, and then pumped into a thickener by a magma pump. The pre-concentrated liquid is sent to a centrifuge, where the mother liquor is separated. The centrifuged and dehydrated sodium sulfate is then transported to a fluidized bed system, dried, sieved, and then fed into a silo. Finally, it is packaged to produce finished sodium sulfate. This acid bath circulation and supply method for spinning consumes a relatively high amount of electricity. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an acid bath circulation system and method for viscose staple fiber production process, which addresses the shortcomings of the prior art.

[0004] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: an acid bath circulation system in the production process of viscose staple fiber, comprising: a circulation main pipe, a filter pump, a filter system, an elevated tank, and an acid distribution bag, wherein the filter pump is connected to the circulation main pipe through a pipeline, the filter system is connected to the filter pump through a pipeline, the elevated tank is connected to the filter system through a pipeline, and the acid distribution bag is connected to the elevated tank through an elevated overflow pipe.

[0005] The beneficial effects of adopting the technical solution of this invention are as follows: the acid bath enters the high-level tank through the filtration system, and the acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. After the acid bath is regulated by the acid distribution package, it is supplied to the spinning and spun yarn tank. The process is simple and feasible, with high working efficiency. Supplying the spinning tank through the overflow of the high-level tank completely eliminates the spinning pump, reducing power consumption. The acid bath supplied to the spinning tank has all passed through the filtration system to remove impurities, avoiding the situation where impurities in the acid bath affect product quality.

[0006] Furthermore, the circulating main pipe is connected to a degassing return tank via a pipeline, and the degassing return tank is connected to a degassing device with negative pressure self-priming function via a pipeline.

[0007] The beneficial effects of adopting the above-mentioned further technical solution are as follows: After the acid bath is used in spinning, it enters the degassing system through the negative pressure self-priming chamber of the degassing device. The acid returned from spinning directly enters the degassing system through the negative pressure of the degassing device in a self-priming manner. The process is simple and feasible, with high working efficiency, completely eliminating the need for a degassing pump and reducing power consumption. All acid bath supplied to spinning has been filtered to remove impurities, avoiding any impact on product quality due to impurities in the acid bath.

[0008] Furthermore, the degassing device is equipped with a negative pressure self-priming chamber, which is connected to a spinning acid return device via a pipeline. The pipeline between the negative pressure self-priming chamber and the spinning acid return device is located at a ground elevation of +24.370m, and the negative pressure of the negative pressure self-priming chamber is 49kPa.

[0009] The beneficial effects of adopting the above-mentioned further technical solution are as follows: After the acid bath is used in spinning, it enters the degassing system through the negative pressure self-priming chamber of the degassing device. The spun acid return directly enters the degassing system through the negative pressure of the degassing device, using a self-priming method. The process is simple and feasible, with high working efficiency, completely eliminating the degassing pump and reducing power consumption. The acid bath supplied to the spinning process has been completely filtered to remove impurities, avoiding the impact of impurities in the acid bath on product quality. When the degassing vacuum is 49 kPa, the degassing rate can reach 1220 m³ / s through negative pressure self-priming feeding. 3 / h.

[0010] Furthermore, a concentrated acid tank is connected to the main circulation pipe near the inlet of the filter pump via a pipeline, and the concentrated acid tank is connected to a flash evaporation acid stripping device via a pipeline.

[0011] The beneficial effects of adopting the above-mentioned further technical solution are as follows: The flash-evaporated acid bath flows to the inlet of the filter pump, passes through a fiber tow filter, and then enters the main circulation system. This process is simple, feasible, and highly efficient, comprehensively removing black spot impurities from the flash-evaporated acid. Re-filtration of the flash-evaporated acid thoroughly removes black spot impurities introduced into the flash evaporation system; operation is simple, and acid bath quality is improved. This improves acid bath quality, reduces energy consumption, and ensures the quality of the finished spun yarn. The flash-evaporated acid bath flows to the concentrated acid tank, which overflows at a high level to the main inlet pipe of the filter pump, where the filter pump draws acid for entry into the filtration system. All acid bath supplied to the spinning process has been filtered to remove impurities, preventing impurities in the acid bath from affecting product quality.

[0012] Furthermore, the filtration system is a fiber bundle filter, and the acid separation package is equipped with an automatic control valve for adjusting the flow rate.

[0013] The beneficial effect of adopting the above-mentioned further technical solution is that the acid bath, after passing through the acid distribution package and having its flow rate regulated by an automatic control valve, is supplied to the spinning and spun yarn tank.

[0014] Furthermore, the acid-dissolving package is connected to a spinning trough via a pipeline.

[0015] The beneficial effect of adopting the above-mentioned further technical solution is that it facilitates the use of the acid bath in the spinning and spun yarn tank after the acid bath has been adjusted by the acid distribution package.

[0016] Furthermore, the elevated tank is located at a ground elevation of +32.750m, the vertical distance from the elevated tank to the acid inlet of the spinning tank is 6.05m, and the acid distribution package is located below the elevated tank.

[0017] The beneficial effects of adopting the above-mentioned further technical solution are: when the vertical distance from the high-level tank to the spinning tank reaches 6.05 meters, the acid bath in the high-level tank can be transported to the spinning tank and the flow rate on each side can reach 1120 m³ / s. 3 / h, the actual vertical distance from the high-level tank to the spinning tank is 6.05 meters, which meets the requirements.

[0018] Furthermore, the present invention also provides an acid bath circulation method in the viscose staple fiber production process, based on the acid bath circulation system in the viscose staple fiber production process described in any one of the above claims. The acid bath circulation method in the viscose staple fiber production process includes: S1, pumping the acid bath in the circulation main pipe into the filtration system through a filter pump; S2, filtering the acid bath through the filtration system so that the acid bath flows into the high-level tank; S3, overflowing the acid bath in the high-level tank to the acid distribution package through the high-level overflow pipe; S4, adjusting the flow rate through the acid distribution package so that the acid bath is supplied to the spinning tank.

[0019] The beneficial effects of adopting the technical solution of this invention are as follows: the acid bath enters the high-level tank through the filtration system, and the acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. After the acid bath is regulated by the acid distribution package, it is supplied to the spinning and spun yarn tank. The process is simple and feasible, with high working efficiency. Supplying the spinning tank through the overflow of the high-level tank completely eliminates the spinning pump, reducing power consumption. The acid bath supplied to the spinning tank has all passed through the filtration system to remove impurities, avoiding the situation where impurities in the acid bath affect product quality.

[0020] Further, before step S1, the process includes: S11, using the negative pressure self-absorption function of the degassing device to draw the spun acid back to the degassing device; S12, using the degassing return trough to transport the spun acid back to the main circulation pipe.

[0021] The beneficial effects of adopting the above-mentioned further technical solution are as follows: After the acid bath is used in spinning, it enters the degassing system through the negative pressure self-priming chamber of the degassing device. The acid returned from spinning directly enters the degassing system through the negative pressure of the degassing device in a self-priming manner. The process is simple and feasible, with high working efficiency, completely eliminating the need for a degassing pump and reducing power consumption. All acid bath supplied to spinning has been filtered to remove impurities, avoiding any impact on product quality due to impurities in the acid bath.

[0022] Furthermore, before step S1, the process includes: S21, collecting the flash outlet acid bath through the concentrated acid tank; S22, overflowing the acid bath from the concentrated acid tank to the main circulation pipe at the inlet of the filter pump.

[0023] The beneficial effects of adopting the above-mentioned further technical solution are as follows: The flash-evaporated acid bath flows to the inlet of the filter pump, passes through a fiber tow filter, and then enters the main circulation system. This process is simple, feasible, and highly efficient, comprehensively removing black spot impurities from the flash-evaporated acid. Re-filtration of the flash-evaporated acid thoroughly removes black spot impurities introduced into the flash evaporation system; operation is simple, and acid bath quality is improved. This improves acid bath quality, reduces energy consumption, and ensures the quality of the finished spun yarn. The flash-evaporated acid bath flows to the concentrated acid tank, which overflows at a high level to the main inlet pipe of the filter pump, where the filter pump draws acid for entry into the filtration system. All acid bath supplied to the spinning process has been filtered to remove impurities, preventing impurities in the acid bath from affecting product quality.

[0024] The advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the acid bath circulation system in the viscose staple fiber production process provided in an embodiment of the present invention.

[0026] Figure 2 This is a schematic flowchart illustrating the acid bath circulation method in the production process of viscose staple fiber provided in an embodiment of the present invention.

[0027] The following are the reference numerals: 1. Main circulating pipe; 2. Filter pump; 3. Filtration system; 4. High-level tank; 5. Acid distribution tank; 6. Degassing reflux tank; 7. Degassing device; 8. Spinning acid return equipment; 9. Concentrated acid tank; 10. Flash evaporation acid removal equipment; 11. Spinning tank. Detailed Implementation

[0028] The principles and features of the present invention are described below with reference to the accompanying drawings. The embodiments described are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0029] like Figure 1 As shown in the figure, an embodiment of the present invention provides an acid bath circulation system for viscose staple fiber production, including: a circulation main pipe 1, a filter pump 2, a filter system 3, an elevated tank 4, and an acid distribution package 5. The filter pump 2 is connected to the circulation main pipe 1 through a pipeline, the filter system 3 is connected to the filter pump 2 through a pipeline, the elevated tank 4 is connected to the filter system 3 through a pipeline, and the acid distribution package 5 is connected to the elevated tank 4 through an elevated overflow pipe.

[0030] The beneficial effects of adopting the technical solution of this invention are as follows: the acid bath enters the high-level tank through the filtration system, and the acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. After the acid bath is regulated by the acid distribution package, it is supplied to the spinning and spun yarn tank. The process is simple and feasible, with high working efficiency. Supplying the spinning tank through the overflow of the high-level tank completely eliminates the spinning pump, reducing power consumption. The acid bath supplied to the spinning tank has all passed through the filtration system to remove impurities, avoiding the situation where impurities in the acid bath affect product quality.

[0031] The acid distribution unit is connected to the spinning trough and is used to supply acid to the spinning process. The spinning acid return unit is used to transport the returned acid from the spinning process. The flash acid removal unit is used to transport the flash acid.

[0032] The present invention provides an acid bath circulation system and method for viscose staple fiber production, which can remove black spot impurities in the flash evaporation outlet acid bath during acid bath preparation and reduce power consumption. It can improve acid bath quality and reduce energy consumption, and ensure the quality of spun finished products.

[0033] To address the problems of traditional acid bath supply via spinning pumps, which require separate pumps for each face of the spinning machine (head and tail), resulting in high energy consumption, heavy workload for workers, and unpredictability, a new method is proposed. In this method, the acid bath passes through a filtration system into a high-level tank. From there, the acid bath overflows through a high-level overflow pipe into a distribution tank. After flow regulation by the distribution tank, the acid bath is supplied to the spinning tub. This process is simple, feasible, highly efficient, and completely eliminates the need for spinning pumps, thus reducing energy consumption.

[0034] To address the problems of traditional acid bath supply to degassing systems via degassing pumps, which require a separate pump for each degassing system, resulting in high energy consumption, heavy workload for workers, and unpredictability, a new method is proposed. In this method, the acid bath, after being used in spinning, enters the degassing system through a negative pressure self-priming chamber. This process is simple, feasible, highly efficient, and completely eliminates the need for degassing pumps, thus reducing power consumption.

[0035] To address the problems of traditional methods for removing black spot impurities from flash-evaporated acid during acid bath preparation, such as long processing time, high workload for workers, randomness, and unpredictability, a new method is proposed. This method involves the flash-evaporated acid bath falling from the outlet to the inlet of a filter pump, being filtered through a fiber bundle filter, and then entering the main circulation system. This process is simple, feasible, highly efficient, and effectively removes black spot impurities from flash-evaporated acid.

[0036] (1) The filtered acid bath is sent to the high-level tank: the acid bath enters the high-level tank through the filtration system, and the acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. After the acid bath passes through the acid distribution package, the flow rate is adjusted by the automatic control valve and then supplied to the spinning and spun yarn tank.

[0037] (2) Spinning acid return directly enters the degassing system: Spinning acid return directly enters the degassing system through the negative pressure of the degassing device in a self-priming manner.

[0038] (3) Flash evaporation outlet acid bath is fed into the filtration system: the flash evaporation outlet acid bath falls into the concentrated acid tank, the concentrated acid tank overflows at a high level to the main inlet pipe of the filter pump, and the filter pump takes acid from here to enter the filtration system.

[0039] ① The high-level tank overflow supply method eliminates the need for a spinning pump, reducing power consumption. ② The acid returned from spinning enters the degassing system via negative pressure from the degassing device, eliminating the need for a degassing pump and further reducing power consumption. Flash evaporation followed by filtration thoroughly removes black spot impurities introduced from the flash evaporation system; this method is simple to operate, highly efficient, and improves acid bath quality. All acid supplied to spinning has been filtered to remove impurities, preventing impurities in the acid bath from affecting product quality.

[0040] like Figure 1 As shown, the circulating main pipe 1 is further connected to a degassing return tank 6 via a pipeline, and the degassing return tank 6 is connected to a degassing device 7 with negative pressure self-priming function via a pipeline.

[0041] The beneficial effects of adopting the above-mentioned further technical solution are as follows: After the acid bath is used in spinning, it enters the degassing system through the negative pressure self-priming chamber of the degassing device. The acid returned from spinning directly enters the degassing system through the negative pressure of the degassing device in a self-priming manner. The process is simple and feasible, with high working efficiency, completely eliminating the need for a degassing pump and reducing power consumption. All acid bath supplied to spinning has been filtered to remove impurities, avoiding any impact on product quality due to impurities in the acid bath.

[0042] like Figure 1 As shown, the degassing device 7 is further provided with a negative pressure self-priming chamber, which is connected to a spinning acid return device 8 via a pipeline. The pipeline between the negative pressure self-priming chamber and the spinning acid return device 8 is located at a ground elevation of +24.370m, and the negative pressure of the negative pressure self-priming chamber is 49kPa.

[0043] The beneficial effects of adopting the above-mentioned further technical solution are as follows: After the acid bath is used in spinning, it enters the degassing system through the negative pressure self-priming chamber of the degassing device. The spun acid return directly enters the degassing system through the negative pressure of the degassing device, using a self-priming method. The process is simple and feasible, with high working efficiency, completely eliminating the degassing pump and reducing power consumption. The acid bath supplied to the spinning process has been completely filtered to remove impurities, avoiding the impact of impurities in the acid bath on product quality. When the degassing vacuum is 49 kPa, the degassing rate can reach 1220 m³ / s through negative pressure self-priming feeding. 3 / h.

[0044] like Figure 1As shown, further, the main circulation pipe 1 is connected to a concentrated acid tank 9 via a pipeline near the inlet of the filter pump 2, and the concentrated acid tank 9 is connected to a flash evaporation acid removal device 10 via a pipeline.

[0045] The beneficial effects of adopting the above-mentioned further technical solution are as follows: The flash-evaporated acid bath flows to the inlet of the filter pump, passes through a fiber bundle filter, and then enters the main circulation system. This process is simple, feasible, and highly efficient, comprehensively removing black spot impurities from the flash-evaporated acid. By filtering the flash-evaporated acid again, black spot impurities introduced into the flash evaporation system are thoroughly removed; operation is simple, and acid bath quality is improved. This improves acid bath quality, reduces energy consumption, and ensures the quality of the finished spun yarn. The flash-evaporated acid bath flows to the concentrated acid tank, which overflows at a high level to the main inlet pipe of the filter pump, where the filter pump draws acid for entry into the filtration system. All acid bath supplied to the spinning process has been filtered to remove impurities, preventing impurities in the acid bath from affecting product quality.

[0046] like Figure 1 As shown, the filtration system 3 is a fiber bundle filter, and the acid separation bag 5 is equipped with a self-regulating valve for adjusting the flow rate.

[0047] The beneficial effect of adopting the above-mentioned further technical solution is that the acid bath, after passing through the acid distribution package and having its flow rate regulated by an automatic control valve, is supplied to the spinning and spun yarn tank.

[0048] like Figure 1 As shown, the acid-dissolving package 5 is further connected to a spinning trough 11 via a pipeline.

[0049] The beneficial effect of adopting the above-mentioned further technical solution is that it facilitates the use of the acid bath in the spinning and spun yarn tank after the acid bath has been adjusted by the acid distribution package.

[0050] like Figure 1 As shown, the high-level tank 4 is located at a ground elevation of +32.750m, the vertical distance from the high-level tank 4 to the acid inlet of the spinning tank 11 is 6.05m, and the acid distribution package 5 is located below the high-level tank 4.

[0051] The beneficial effects of adopting the above-mentioned further technical solution are: when the vertical distance from the high-level tank to the spinning tank reaches 6.05 meters, the acid bath in the high-level tank can be transported to the spinning tank and the flow rate on each side can reach 1120 m³ / s. 3 / h, the actual vertical distance from the high-level tank to the spinning tank is 6.05 meters, which meets the requirements.

[0052] This invention provides an acid bath circulation system and method for viscose staple fiber production, which can be used as a novel method for acid bath circulation and supply to spinning in viscose staple fiber production. The method adopts a flash evaporation process, a concentrated acid tank (concentrated acid bath), a filter pump, a fiber tow filter (filtration system), a high-level tank, etc. The acid bath is self-primed by the spinning process and enters the degassing system. The acid bath at the flash evaporation outlet falls to the inlet of the filter pump, is filtered by the fiber tow filter (fiber tow filter), and then goes to the high-level tank. Finally, it is supplied to the spinning process through the high-level overflow of the high-level tank.

[0053] (1) The filtered acid bath is sent to the high-level tank: the acid bath enters the high-level tank through the filtration system, and the acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. After the acid bath passes through the acid distribution package, the flow rate is adjusted by the automatic control valve and then supplied to the spinning and spun yarn tank.

[0054] (2) Spinning acid return directly enters the degassing system: Spinning acid return directly enters the degassing system through the negative pressure of the degassing device in a self-priming manner.

[0055] (3) Flash distillation of acid into the filtration system: Flash distillation of acid into the concentrated acid tank, the high-level overflow of the concentrated acid tank F4 to the main inlet pipe of the filter pump, and the filter pump takes acid from here to enter the filtration system.

[0056] A novel acid bath circulation and supply method for viscose staple fiber production includes: a degassing device, a degassing reflux tank, a concentrated acid tank, a fiber tow filter, an elevated tank, an acid distribution package, and a main circulation pipe. The elevated tank is located at an elevation of +32.750m, and the spinning machine is located at an elevation of +22.000m. The horizontal distance between the spinning machine and the elevated tank is 30 meters. There are two DN700 valves and five DN700 elbows. Using Bernoulli's equation and pipe resistance calculations (P = ρgh), when the vertical distance from the elevated tank to the spinning tank reaches 6.05 meters, the acid bath in the elevated tank can be transported to the spinning tank with a flow rate of 1120 m³ / s. 3 / h. The actual vertical distance from the high-level tank to the spinning tank is 6.05 meters, which meets the requirements. The acid inlet pipe of the degassing device is located at a ground elevation of +24.370m. The horizontal distance between the spinning machine and the degassing device is 70 meters. There are 2 DN700 valves and 6 DN700 elbows. By applying Bernoulli's equation and calculating the pipe resistance, P = ρgh, when the degassing vacuum is 49 kPa, the degassing can reach a feed rate of 1220 m³ / h through negative pressure self-priming. 3 / h. The actual degassing vacuum control of 14 kPa or higher meets the requirements. During implementation, the degassing pump and spinning pump were eliminated, resulting in a total annual power saving of (55+90)*8000=4640000kw and an annual profit of 4640000*0.46=213.44 million yuan.

[0057] like Figure 2As shown, this invention also provides an acid bath circulation method in the viscose staple fiber production process. Based on the acid bath circulation system in the viscose staple fiber production process described in any one of the above claims, the acid bath circulation method in the viscose staple fiber production process includes: S1, pumping the acid bath in the circulation main pipe into the filtration system through a filter pump; S2, filtering the acid bath through the filtration system so that the acid bath flows into the high-level tank; S3, overflowing the acid bath in the high-level tank to the acid distribution package through the high-level overflow pipe; S4, adjusting the flow rate through the acid distribution package so that the acid bath is supplied to the spinning tank.

[0058] The beneficial effects of adopting the technical solution of this invention are as follows: the acid bath enters the high-level tank through the filtration system, and the acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. After the acid bath is regulated by the acid distribution package, it is supplied to the spinning and spun yarn tank. The process is simple and feasible, with high working efficiency. Supplying the spinning tank through the overflow of the high-level tank completely eliminates the spinning pump, reducing power consumption. The acid bath supplied to the spinning tank has all passed through the filtration system to remove impurities, avoiding the situation where impurities in the acid bath affect product quality.

[0059] This system employs a flash evaporation process, a concentrated acid tank, a one-step nitration process, a filter pump, a fiber bundle filter, and an elevated tank. Acid from the spinning process is self-primed into the degassing system. Flash-evaporated acid is fed to the filter pump inlet, then filtered through the fiber bundle filter, and finally into the elevated tank. The degassing system (degassing unit) provides self-priming acid supply, flash-evaporated acid is filtered again, and the filtered acid bath enters the elevated tank, with overflow from the elevated tank supplying the spinning process. This thoroughly removes black spot impurities introduced from the flash evaporation system and eliminates the need for spinning and degassing pumps. Compared to traditional methods of removing black spot impurities from flash-evaporated acid and methods of supplying the spinning process with a spinning pump and the degassing system with a degassing pump, this system is simpler to operate, more efficient, improves acid bath quality, and reduces power consumption.

[0060] Further, before step S1, the process includes: S11, using the negative pressure self-absorption function of the degassing device to draw the spun acid back to the degassing device; S12, using the degassing return trough to transport the spun acid back to the main circulation pipe.

[0061] The beneficial effects of adopting the above-mentioned further technical solution are as follows: After the acid bath is used in spinning, it enters the degassing system through the negative pressure self-priming chamber of the degassing device. The acid returned from spinning directly enters the degassing system through the negative pressure of the degassing device in a self-priming manner. The process is simple and feasible, with high working efficiency, completely eliminating the need for a degassing pump and reducing power consumption. All acid bath supplied to spinning has been filtered to remove impurities, avoiding any impact on product quality due to impurities in the acid bath.

[0062] Furthermore, before step S1, the process includes: S21, collecting the flash outlet acid bath through the concentrated acid tank; S22, overflowing the acid bath from the concentrated acid tank to the main circulation pipe at the inlet of the filter pump.

[0063] The beneficial effects of adopting the above-mentioned further technical solution are as follows: The flash-evaporated acid bath flows to the inlet of the filter pump, passes through a fiber bundle filter, and then enters the main circulation system. This process is simple, feasible, and highly efficient, comprehensively removing black spot impurities from the flash-evaporated acid. By filtering the flash-evaporated acid again, black spot impurities introduced into the flash evaporation system are thoroughly removed; operation is simple, and acid bath quality is improved. This improves acid bath quality, reduces energy consumption, and ensures the quality of the finished spun yarn. The flash-evaporated acid bath flows to the concentrated acid tank, which overflows at a high level to the main inlet pipe of the filter pump, where the filter pump draws acid for entry into the filtration system. All acid bath supplied to the spinning process has been filtered to remove impurities, preventing impurities in the acid bath from affecting product quality.

[0064] The acid bath is supplied by a negative pressure self-priming degassing device. The acid bath from the flash evaporation outlet falls to the inlet of the filter pump, is filtered by the fiber bundle filter (filtration system), and then flows to the high-level tank. The acid bath overflows from the high-level tank to the spinning tank (spinning tank). The method mainly includes the following steps:

[0065] (1) Change the supply method of spinning: change from the original spinning pump to high-level tank supply, that is, the acid bath enters the high-level tank through the filtration system, and the acid bath in the high-level tank enters the acid distribution package through the high-level overflow pipe. After the acid bath is adjusted by the acid distribution package, it is supplied to the spinning and spinning tank.

[0066] (2) Change the degassing acid supply method: change from the original spinning acid returning to the degassing bottom tank and being supplied to the degassing system through the degassing pump to the negative pressure self-priming of the degassing device into the degassing system.

[0067] (3) Flash outlet acid bath is put back into the filtration system: The flash outlet acid bath falls into the concentrated acid tank, and the concentrated acid tank overflows to the filter pump inlet main pipe (circulation main pipe) at a high level. The filter pump takes the acid bath here and puts it into the filtration system.

[0068] (4) The high-level tank is located at a height of 6.05 meters or more from the acid inlet of the spinning tank.

[0069] (5) The acid pack is located below the height of the high-level tank.

[0070] (6) The negative pressure reaches below 49 kPa, ensuring that the self-priming flow rate reaches 1220 m³ / h. 3 / h.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An acid bath circulation system for viscose staple fiber production, characterized in that, include: The system includes a main circulation pipe, a filter pump, a filtration system, an elevated tank, and an acid distribution package. The filter pump is connected to the main circulation pipe via a pipeline, the filtration system is connected to the filter pump via a pipeline, the elevated tank is connected to the filtration system via a pipeline, and the acid distribution package is connected to the elevated tank via an elevated overflow pipe. The main circulation pipe is connected to a degassing reflux tank via a pipeline, and the degassing reflux tank is connected to a degassing device with negative pressure self-priming function via a pipeline. A concentrated acid tank is connected to the main circulation pipe near the inlet of the filter pump via a pipeline, and the concentrated acid tank is connected to a flash evaporation acid removal device via a pipeline. The filtration system is a fiber bundle filter. The acid distribution package is equipped with a self-regulating valve for adjusting the flow rate. The acid distribution package is connected to the spinning trough via a pipeline. The degassing device is equipped with a negative pressure self-priming chamber, which is connected to a spinning acid return device via a pipeline. The pipeline between the negative pressure self-priming chamber and the spinning acid return device is located at a ground elevation of +24.370m, and the negative pressure of the negative pressure self-priming chamber is 49kPa. The high-level tank is located at a ground elevation of +32.750m, and the vertical distance from the high-level tank to the acid inlet of the spinning trough is 6.05m. The acid distribution package is located below the high-level tank.

2. A method for acid bath circulation in the production process of viscose staple fiber, characterized in that, Based on the acid bath circulation system for viscose staple fiber production according to claim 1, the acid bath circulation method for viscose staple fiber production includes: S1. Pump the acid bath in the main circulation pipe into the filtration system using a filter pump. S2. After the acid bath is filtered by the filtration system, the acid bath flows into the high-level tank. S3. Overflow the acid bath in the high-level tank to the acid distribution package through the high-level overflow pipe; S4. After adjusting the flow rate by dividing the acid bath, the acid bath is supplied to the spinning tank. Before step S1, the following are included: S11. The negative pressure self-priming function of the degassing device draws the spun acid back to the degassing device; S12. The scouring acid is transported to the main circulation pipe through the degassing reflux tank; Step S1 is preceded by: S21. Collect the flash evaporation outlet acid bath through the concentrated acid tank; S22. The acid bath overflows from the concentrated acid tank to the main circulation pipe at the inlet of the filter pump.

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