Viscose filament pressure washing system and soft water utilization method thereof

Abstract

The invention belongs to the technical field of viscose filament pressure washing, and particularly relates to a viscose filament pressure washing system and a soft water utilization method thereof, the system is provided with a soft water replenishing pipe network, a soft water recycling pipe network and 14 treatment stations, and each station is provided with a blow-off pipeline and a blow-off bottom valve. A main pipeline of the soft water replenishing pipe network is connected with related stations through ten replenishing pipelines, and the soft water recycling pipe network comprises a plurality of water return pipes and water return valves. The soft water utilization method comprises the steps of determining a station function, laying a pipe network, injecting fresh soft water until the liquid level reaches 80%-90%, then adjusting a valve to enter a station soft water circulation mode, and maintaining the liquid level at 75%-95%. The technical scheme has the advantages in multiple aspects, in the aspect of soft water recycling, the water utilization efficiency is improved through the multi-stage recycling channel, the pollution problem is relieved, and the washing and pollution discharging capacity is enhanced; in the aspects of EDTA disodium complexation zinc ion removal and pH adjustment, the consumption of chemical materials is reduced by utilizing liquid characteristics, and the pH value is stabilized to ensure the product quality; and on the whole system design, the functions are diversified, the spinning cake processing effect is enhanced, and accurate liquid level control is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of viscose filament pressure washing, and in particular relates to a viscose filament pressure washing system and a soft water utilization method thereof. Background Art

[0002] Viscose filament pressure washing is an important part of viscose filament production. After spinning, viscose filament contains more impurities (such as sulfuric acid, zinc sulfate and other coagulation bath components). Pressure washing is mainly to remove these impurities. The principle is to dissolve the impurities in the filament and carry them away by the washing liquid through mechanical extrusion and circulation of washing liquid.

[0003] In actual production, soft water is generally used as the washing liquid of viscose filaments, such as a pressure washing process suitable for protein viscose filament refining disclosed in the Chinese patent literature of publication number CN102418261A, that is, soft water is used to participate in the pressure washing of viscose filaments. The pressure washing of viscose filaments with soft water is mainly based on the following principles: first, viscose filaments will carry impurities during the production process, such as chemical substances (such as sulfuric acid, zinc sulfate, etc.) in the coagulation bath, and soft water, as a washing medium, can dissolve and take away these impurities. Secondly, the hardness of soft water is relatively low, and the content of calcium, magnesium and other ions is extremely small, which is a very important point, because if the water contains more calcium and magnesium ions, it may react with the material on the surface of the filament during the washing process, or form a precipitation attached to the filament, affecting the quality of the filament. Finally, in the pressure washing process, by applying a certain pressure, the soft water can better penetrate into the inside of the filament and fully contact with the impurities. The pressure causes the soft water to flow between the filaments, speeding up the separation of impurities from the inside and surface of the filaments, and allowing the water containing impurities to be replaced by new soft water in time, thereby more effectively cleaning the viscose filaments.

[0004] However, the existing pressure washing process has the following problems:

[0005] 1. Soft water reuse issues at pressure washing and water washing stations

[0006] The pressure washing line generally contains 10-20 treatment stations (pressure washing stations), among which the water washing stations usually adopt a step-by-step water return mode, that is, the water from the last water washing station is reused in turn to the previous station. In this process, fresh soft water is rarely used or not used. This water return reuse method can greatly reduce the amount of fresh water. However, due to the continuous recycling of water, pollutants in the return water will gradually accumulate. As the concentration of pollutants increases, the entire operation cycle will be shortened, affecting the continuity and stability of production.

[0007] 2. Problems of removing zinc ions by complexation of disodium EDTA and pH adjustment before alkali washing station

[0008] In the post-processing process of viscose filament, disodium EDTA is used to remove zinc ions by complexation before the alkali washing station. The reason for this is that zinc ions can cause white spots on the silk cake, affecting the quality of the silk cake. Disodium EDTA can form stable complexes with metal ions when the pH value is in the range of 4.7-9.7. The raw silk cake after semi-continuous spinning of filaments is acidic. When it enters the pressure washing line, the pH value of the washing liquid before the alkali washing station is relatively low (about 3). When the pH value is lower than 3, the complexing ability of disodium EDTA will be adversely affected, so it is necessary to adjust the pH at the EDTA station. At present, most people directly use sodium hydroxide to adjust the pH. This method is simple to operate and fast. However, the use of sodium hydroxide for adjustment will bring new problems, that is, it will increase the consumption of other chemical materials and increase production costs. Summary of the invention

[0009] In view of the problems existing in the above-mentioned prior art, the present technical scheme proposes a viscose filament pressure washing system and a soft water utilization method thereof, so as to solve the problems that pollutants are easily accumulated in the step-by-step return water of the pressure washing station, the operation cycle of the station tank is short, and the pH of the EDTA station is adjusted by adding sodium hydroxide or soft water, which increases the consumption of chemical materials and water.

[0010] The above objectives are achieved specifically through the following technical solutions:

[0011] A viscose filament pressure washing system comprises a soft water supply pipe network, a soft water recycling pipe network and 14 sequentially arranged processing stations.

[0012] Among the 14 treatment stations, each treatment station is equipped with a sewage pipe, and the sewage pipe is connected to a sewage bottom valve; Station 1 is the pickling station, Station 3 is the EDTA station, Station 4 and Station 5 are alkali washing stations, Station 14 is the oil agent station, and Station 2 and Stations 6 to 13 are all water washing stations.

[0013] The soft water replenishing pipe network includes a main pipe and 10 soft water replenishing pipes. The main pipe is connected to the second station, the third station and the sixth to the thirteenth station through the 10 soft water replenishing pipes one by one. The 10 soft water replenishing pipes are respectively connected with soft water replenishing valves.

[0014] The soft water reuse pipe network includes return pipe I, return pipe II, return pipe III, and return pipe IV; return pipe I is connected from the 13th station to the 11th station, and return pipe I is connected to a return valve I; return pipe II is connected from the 11th station to the 6th station, and return pipe II is connected to a return valve II; return pipe III is connected from the 12th station to the 7th station and the 8th station, and return pipe III is provided with return valve III and return valve IV corresponding to the 7th station and the 8th station respectively; return pipe IV is connected from the 8th station to the 6th station, and return pipe IV is connected to a return valve V.

[0015] Preferably, the soft water recycling network further includes a return pipe V, which is connected from the 7th station to the 2nd station and the 3rd station; a return valve VI and a return valve VII are respectively provided in the return pipe V corresponding to the 2nd station and the 3rd station.

[0016] Preferably, the soft water recycling network also includes a return pipe VI and a return pipe VII; the return pipe VI is connected from the third station to the second station, and the return pipe VII is connected from the second station to the first station; the return pipe VI and the return pipe VII are respectively connected with a return valve VIII and a return valve IX.

[0017] A soft water utilization method based on a viscose filament pressure washing system comprises the following steps:

[0018] S1, determine the function of each processing station in the viscose filament pressing and washing system, that is, the viscose filament pressing and washing system includes 14 processing stations, of which the first station is an acid washing station, the third station is an EDTA station, the fourth and fifth stations are alkali washing stations, the fourteenth station is an oil station, and the remaining nine processing stations are water washing stations;

[0019] S2, laying out the pipe network, including: configuring soft water replenishment pipes and sewage pipes for all treatment stations, and connecting each treatment station to the main pipe through the soft water replenishment pipe; setting a return pipe I with a return valve I, connecting from the 13th station to the 11th station; setting a return pipe II with a return valve II, connecting from the 11th station to the 6th station; setting a return pipe III with return valves III and IV, connecting from the 12th station to the 7th station and the 8th station; setting a return pipe IV with a return valve V, connecting from the 8th station to the 6th station;

[0020] S3, close all sewage bottom valves and return valves, open the soft water replenishment valves on all soft water replenishment pipes, and inject fresh soft water into each treatment station through the soft water replenishment pipe until the liquid level in each treatment station reaches 80% to 90% of its total capacity;

[0021] S4, adjust the opening of each soft water replenishing valve, sewage bottom valve and return water valve, so that the viscose filament pressure washing system enters the station soft water circulation mode; during the station soft water circulation process, the return water volume is controlled by each return water valve, and the soft water replenishing valve and sewage bottom valve are coordinated to maintain the liquid level in each processing station at 75% to 95% of its own capacity.

[0022] Preferably, in step S4, during the station soft water circulation process, the ratio of fresh soft water added to the 14 treatment stations in the same time period is 0:15:9:3:6:6:9:3:3:15:15:0.

[0023] Preferably, in step S4, during the soft water circulation at the stations, the ratio of the soft water addition, sewage discharge and return water outflow in the 13th station is 5:2:3; the ratio of the soft water addition, sewage discharge, return water inflow and return water outflow in the 11th station is 1:1:3:3.

[0024] Preferably, in step S4, during the soft water circulation at the stations, the ratio of the soft water addition, sewage discharge and return water outflow in the 12th station is 15:4:11; the ratio of the soft water addition, sewage discharge, return water inflow and return water outflow in the 8th station is 2:2:1:1.

[0025] Preferably, in step S2, laying the pipe network further includes providing a return pipe V with a return valve VI and a return valve VII, and connecting the return pipe V from the 7th station to the 2nd station and the 3rd station.

[0026] Preferably, in step S4, during the soft water circulation at the stations, the ratio of soft water addition, sewage discharge, return water inflow and return water outflow in the 7th station is 6:3:8:11; among which, the ratio of soft water return from the 7th station to the 3rd and 2nd stations is 6:5.

[0027] Preferably, in step S2, laying the pipe network also includes providing a return pipe VI with a return valve VIII and a return pipe VII with a return valve IX, connecting the return pipe VI from the third station to the second station, and connecting the return pipe VII from the second station to the first station.

[0028] Preferably, in step S4, during the soft water circulation process at the stations, the ratio of soft water addition, sewage discharge, backwater inflow and backwater outflow at the third station is 3:3:2:2; and the ratio of soft water addition, sewage discharge, backwater inflow and backwater outflow at the second station is 15:24:11:2.

[0029] Beneficial effects of the present invention:

[0030] 1. Optimization of soft water reuse:

[0031] 1) Improve water efficiency and reduce fresh water consumption: Compared with the existing pressure washing process, the step-by-step water return mode adopted by the water washing station can reduce the amount of fresh water used, but the continuous recycling of water will lead to the accumulation of pollutants and shorten the operation cycle. This technical solution constructs a multi-stage soft water recovery and treatment channel, which ensures water efficiency and alleviates the problem of pollutant accumulation to a certain extent. For example, in Example 1, there are two sections of 3-stage soft water recovery and treatment channels, "Station 13 → Station 11 → Station 6" and "Station 12 → Station 8 → Station 6"; on this basis, Example 2 adds a 3-stage soft water recovery treatment of "Station 12 → Station 7 → Station 3 (Station 2)"; Example 3 adds a 3-stage soft water recovery and treatment channel of "Station 3 → Station 2 → Station 1". This multi-stage recovery and treatment method not only realizes the reuse of water, but also reduces the impact of water quality deterioration caused by the return water reuse on production.

[0032] 2) Enhanced washing effect and sewage discharge capacity: In this technical solution, the design is optimized according to the characteristics of different treatment stations. As in Example 1, the 6th station is the first treatment station after alkali washing. Two-stage 3-level return water is used to pass into the 6th station, which increases the water intake and sewage discharge of the 6th station, and enhances the replacement effect of fresh water in the station as a whole, improving the washing effect. In addition, each embodiment reasonably sets the amount of fresh soft water added and the return water ratio according to the impurity conditions and treatment requirements of different stations, so that the washing and sewage discharge of each station are more efficient.

[0033] 2. EDTA disodium complexation to remove zinc ions and pH adjustment:

[0034] 1) Reduce the consumption of chemical materials and reduce production costs: Compared with the prior art, which mostly directly uses sodium hydroxide to adjust the pH, it will increase the consumption of other chemical materials. This technical solution uses the liquid characteristics of different stations in the system to adjust the pH value, reducing the demand for additional chemical materials. For example, in Example 2 and Example 3, the pH value of the internal liquid of the second station (station 7) after the alkali washing station is higher, and the return water mechanism of station 7 → station 3 (station 2) is adopted to weaken the acidity of station 3 (station 2), so that the silk cake washed by stations 2 and 3 enters station 4 for washing, and the liquid pH in station 3 meets the EDTA use requirements (pH value is 4 to 6), and there is no need to add too much fresh soft water or sodium hydroxide to adjust the pH value, thereby reducing production costs.

[0035] 2) Stabilize pH value and improve product quality: Through precise station design and water return mechanism, the pH value of each station is more stable, which is conducive to meeting the optimal pH conditions for EDTA complexing zinc ions, thereby improving the quality of silk cakes. For example, in Example 3, the pH control requirements for each station are strict, the pH of the EDTA station at the third station is controlled within the range of 4 to 6, and the pH of the washing station at the 12th station is controlled within the range of 7.5 to 8.5, ensuring the stability of the production process and the quality of the product.

[0036] 3. Overall system design and functionality:

[0037] 1) Diversification of system functions: The three-stage soft water recovery and treatment channel of "Station 3 → Station 2 → Station 1" added in Example 3 not only strengthens the sulfuric acid washing in Station 1, but also replaces the water washing in Stations 2 and 3 before alkali washing with the water washing in Stations 6 and 7 after alkali washing. At the same time, the pH is adjusted by returning water for the use of EDTA in Station 3, thereby realizing multifunctional utilization and making the function of the entire pressure washing system more perfect.

[0038] 2) Enhanced silk cake treatment effect: In Example 3, more fresh soft water is added to the 9th station, which enhances the water washing of the silk cake at this station, and quickly reduces the pH of the silk cake to close to neutral, which is beneficial to the subsequent oiling at the 14th station, thereby improving the silk cake treatment effect and the convenience of subsequent processing.

[0039] 3) Accurate liquid level control: All embodiments emphasize that the control requirement for the washing liquid level in each processing station is 75%-95%. By adjusting the opening of the soft water replenishment valve, the sewage bottom valve and the return water valve, the liquid level can be accurately controlled to ensure the stability and consistency of the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The figure is a schematic diagram of the connection structure of a viscose filament pressure washing system.

[0041] In the figure:

[0042] 1. Sewage pipe; 2. Sewage bottom valve; 3. Main pipe; 4. Soft water supply pipe; 5. Soft water supply valve; 6. Return pipe I; 7. Backwater valve I; 8. Return pipe II; 9. Backwater valve II; 10. Return pipe III; 11. Backwater valve III; 12. Backwater valve IV; 13. Return pipe IV; 14. Backwater valve V; 15. Return pipe V; 16. Backwater valve VI; 17. Backwater valve VII; 18. Return pipe VI; 19. Backwater valve VIII; 20. Return pipe VII; 21. Backwater valve IX. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiments of the present invention. It should not be understood that the present invention is limited to the following examples. Without departing from the concept of the present invention, the deformation and improvement of the present invention in this field should be included in the protection scope of the claims of the present invention.

[0044] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The words "or", "comprising" and the like used in the present disclosure 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.

[0045] Example 1

[0046] This embodiment discloses a viscose filament pressure washing system and a soft water utilization method thereof, as a basic implementation scheme of the present technical scheme, such as Figure 1 As shown, the viscose filament pressure washing system includes a soft water supply network, a soft water reuse network and 14 treatment stations arranged in sequence.

[0047] Among the 14 processing stations, each processing station is provided with a sewage pipe 1, and a sewage bottom valve 2 is connected to the sewage pipe 1. The first station is an acid washing station, which is used to react metal ions to form soluble metal sulfates and remove them. The third station is an EDTA (ethylenediaminetetraacetic acid) station, the fourth station (not shown) and the fifth station (not shown) are alkaline washing stations, the fourteenth station (not shown) is an oil station, and the second station and the sixth to thirteenth stations are all water washing stations, which are used to remove sulfur, sulfates, sulfides and washing liquids on the surface of the silk strips. The first station, the fourth station, the fifth station and the fourteenth station have their own opposing liquid replenishment pipelines and liquid circulation pipe network structures.

[0048] The soft water replenishing pipe network includes a main pipeline 3 and 10 soft water replenishing pipes 4. The main pipeline 3 is connected to the second station, the third station and the sixth to the thirteenth stations through the 10 soft water replenishing pipes 4 one by one. The 10 soft water replenishing pipes 4 are respectively connected with soft water replenishing valves 5.

[0049] The soft water reuse pipe network includes return pipe I6, return pipe II8, return pipe III10 and return pipe IV13; return pipe I6 is connected from the 13th station to the 11th station, and a return valve I7 is connected to the return pipe I6; return pipe II8 is connected from the 11th station to the 6th station, and a return valve II9 is ​​connected to the return pipe II8; return pipe III10 is connected from the 12th station to the 7th station and the 8th station, and a return valve III11 and a return valve IV12 are respectively provided in the return pipe III10 corresponding to the 7th station and the 8th station; return pipe IV13 is connected from the 8th station to the 6th station, and a return valve V14 is connected to the return pipe IV13.

[0050] Therefore, in practical application, the soft water utilization method based on the above-mentioned viscose filament pressure washing system specifically includes the following steps:

[0051] S1, determine the function of each processing station in the viscose filament press washing system, that is: the viscose filament press washing system includes 14 processing stations, among which the first station is the pickling station, the third station is the EDTA station, the fourth station (not shown) and the fifth station are the alkali washing stations, the fourteenth station is the oil station, and the second station and the sixth to the thirteenth stations are all water washing stations.

[0052] S2, laying out the pipe network, that is, laying out the soft water supply pipe network and the soft water recycling pipe network according to the structure of the aforementioned viscose filament pressure washing system.

[0053] S3, close all sewage bottom valves 2 and return valves, open the soft water replenishing valves 5 on all soft water replenishing pipes 4, and inject fresh soft water into each treatment station through the soft water replenishing pipe 4 until the liquid level in each treatment station reaches 80% to 90% of its total capacity.

[0054] S4, adjust the opening of each soft water replenishing valve 5, the sewage bottom valve 2 and the return water valve, so that the viscose filament pressure washing system enters the station soft water circulation mode; in the process of station soft water circulation, the return water volume is controlled by each return water valve, and the soft water replenishing valve 5 and the sewage bottom valve 2 are cooperated to maintain the liquid level in each processing station at 75% to 95% of its own capacity.

[0055] In the technical scheme, according to the structure of the viscose filament pressure washing system, in the station soft water circulation mode, there are two sections of 3-level soft water recovery and treatment channels, "Station 13 → Station 11 → Station 6" and "Station 12 → Station 8 → Station 6". On the one hand, two sections of multi-level return water are used to save soft water replenishment. On the other hand, since Station 6 is the first treatment station after alkali washing, it is necessary to strengthen washing and sewage discharge. Therefore, two sections of 3-level return water are used to pass into Station 6, that is, the fresh soft water added by Station 12 and Station 13 is returned to Station 6 through only two treatment stations, thus increasing the water intake of Station 6. Under this condition, the sewage discharge of Station 6 can be further increased, which enhances the replacement effect of fresh water in the stations as a whole and strengthens the washing effect of Station 6. In addition, since Station 8 is closer to the front and the impurities in the silk cake are relatively more than those in Station 11, the sewage discharge of Station 8 is larger than that of Station 11. In summary, the inflow and outflow of soft water in the 6th, 8th, 11th, 12th and 13th stations can be shown in the following table:

[0056]

[0057] That is, the ratio of fresh soft water addition in the 13th station, the 12th station, the 11th station, the 8th station and the 6th station can be set to 5:5:1:2:1; the ratio of fresh soft water addition, sewage discharge and return water outflow in the 13th station is 5:2:3; the ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 11th station is 1:1:3:3; the ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 12th station is 15:4:0:11; the ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 8th station is 2:2:1:1; the ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 6th station is 1:5:4:0. Among them, the fresh soft water added in the 6th, 8th and 11th stations is only used to make up for the amount lost in the silk cake washing and to maintain the liquid level. The return water in each section mainly plays a role in replacement washing, that is, if the liquid level in the 6th, 8th and 11th stations is lower than 75% of its own capacity or higher than 95% of its own capacity, the corresponding soft water replenishment valve 5 can be appropriately adjusted to control the liquid level within the range of 75% to 95%. The ratio of the fresh soft water replenishment amount to the sewage discharge in the other treatment stations can be adaptively set according to needs.

[0058] This technical solution has the following advantages:

[0059] 1) The cleaning function is diversified and targeted. The main performance is: the system contains 14 processing stations with clear functions. The pickling station can react with metal ions to form soluble metal sulfates and remove them, effectively removing metal impurities. The EDTA station can remove zinc ions by complexation to prevent white spots on the silk strips, which is very important for ensuring the appearance quality of the silk strips, because the presence of zinc ions may cause white spots on the silk strips, affecting the appearance and quality of the product. The alkali washing station can remove sulfur from the inside of the silk strips to prevent the silk strips from turning yellow and ensure the feel of the silk thread. Sulfur will make the silk strips turn yellow and affect their quality. Alkaline washing can solve this problem well. The oiling station is used to oil the silk strips, which can lubricate the silk threads, reduce friction, improve the cohesion of the silk strips, enhance the strength of the silk threads, and help the subsequent processing and use of the silk strips. Multiple water washing stations can remove sulfur, sulfates, sulfides and detergents on the surface of the silk strips to fully clean the silk strips.

[0060] 2) Efficient recycling of water resources. The main performance is as follows: the design of the soft water recycling network is ingenious. Through the return pipe I6, return pipe II8, return pipe III10 and return pipe IV13, a three-stage return water channel is realized, of which two stages are 3-stage soft water recovery and treatment. This multi-stage return water method can effectively save fresh soft water replenishment and reduce water consumption. For example, in actual operation, the return water volume is controlled by each return water valve, and the soft water replenishment valve 5 and the sewage bottom valve 2 are used to maintain the liquid level in each treatment station within a certain range, which not only prevents the liquid level from being too low and the tank from being empty, but also prevents the liquid from overflowing, thus realizing the high efficiency of soft water reuse in the washing station.

[0061] 3) Enhance the washing effect of key stations. The main performance is: the system has a special design for the washing effect of the 6th station. Since the 6th station is the first treatment station after alkali washing, it needs to enhance washing and sewage discharge. The two-stage 3-level return water is passed into the 6th station, which increases the water inlet of the 6th station, and then increases the sewage discharge of the 6th station. At the same time, the fresh soft water added by the 12th and 13th stations is returned to the 6th station through only two treatment stations, which increases the sewage discharge of the 6th station, enhances the replacement effect of the fresh water in the later stations, and further enhances the washing effect of the 6th station.

[0062] 4) Flexible water volume control. Specifically, according to the functions and needs of different stations, different ratios of fresh soft water addition, sewage discharge and return water flow are set, which can better meet the actual needs of each station and achieve accurate water volume control.

[0063] Example 2

[0064] This embodiment discloses a viscose filament pressure washing system and a soft water utilization method thereof, as a basic implementation scheme of the present technical scheme, such as Figure 1 As shown, the viscose filament pressure washing system includes a soft water supply network, a soft water reuse network and 14 treatment stations arranged in sequence.

[0065] Among the 14 processing stations, each processing station is provided with a sewage pipe 1, and a sewage bottom valve 2 is connected to the sewage pipe 1. The first station is an acid washing station, which is used to react metal ions to form soluble metal sulfates and remove them. The third station is an EDTA (ethylenediaminetetraacetic acid) station, the fourth station (not shown) and the fifth station (not shown) are alkaline washing stations, the fourteenth station (not shown) is an oil station, and the second station and the sixth to thirteenth stations are all water washing stations, which are used to remove sulfur, sulfates, sulfides and washing liquids on the surface of the silk strips. The first station, the fourth station, the fifth station and the fourteenth station have their own opposing liquid replenishment pipelines and liquid circulation pipe network structures.

[0066] The soft water replenishing pipe network includes a main pipeline 3 and 10 soft water replenishing pipes 4. The main pipeline 3 is connected to the second station, the third station and the sixth to the thirteenth stations through the 10 soft water replenishing pipes 4 one by one. The 10 soft water replenishing pipes 4 are respectively connected with soft water replenishing valves 5.

[0067] The soft water recycling network includes return pipe I6, return pipe II8, return pipe III10, return pipe IV13 and return pipe V15. Return pipe I6 is connected from the 13th station to the 11th station, and a return valve I7 is connected to the return pipe I6. Return pipe II8 is connected from the 11th station to the 6th station, and a return valve II9 is ​​connected to the return pipe II8. Return pipe III10 is connected from the 12th station to the 7th station and the 8th station, and return valves III11 and IV12 are respectively provided in the return pipe III10 corresponding to the 7th station and the 8th station. Return pipe IV13 is connected from the 8th station to the 6th station, and a return valve V14 is connected to the return pipe IV13. The return pipe V15 is connected from the 7th station to the 2nd station and the 3rd station; the return pipe V15 is provided with a return valve VI16 and a return valve VII17 corresponding to the 2nd station and the 3rd station respectively.

[0068] Therefore, in practical application, the soft water utilization method based on the above-mentioned viscose filament pressure washing system specifically includes the following steps:

[0069] S1, according to the structure of the viscose filament pressing and washing system, determine the function of each processing station in the viscose filament pressing and washing system.

[0070] S2, laying out the pipe network, that is, laying out the soft water supply pipe network and the soft water recycling pipe network according to the structure of the aforementioned viscose filament pressure washing system.

[0071] S3, close all sewage bottom valves 2 and return valves, open the soft water replenishing valves 5 on all soft water replenishing pipes 4, and inject fresh soft water into each treatment station through the soft water replenishing pipe 4 until the liquid level in each treatment station reaches 80% to 90% of its total capacity.

[0072] S4, adjust the opening of each soft water replenishing valve 5, the sewage bottom valve 2 and the return water valve, so that the viscose filament pressure washing system enters the station soft water circulation mode; in the process of station soft water circulation, the return water volume is controlled by each return water valve, and the soft water replenishing valve 5 and the sewage bottom valve 2 are cooperated to maintain the liquid level in each processing station at 75% to 95% of its own capacity.

[0073] In this technical solution, according to the structure of the viscose filament pressure washing system, in the station soft water circulation mode, there are four sections of three-level soft water recovery and treatment channels, namely "Station 13 → Station 11 → Station 6", "Station 12 → Station 8 → Station 6" and "Station 12 → Station 7 → Station 3 (Station 2)". Among them, since a large amount of metal ions are dissolved after washing in Station 1, it is necessary to increase the soft water replenishment and sewage discharge in Stations 2 and 3, strengthen the fresh soft water replacement in Stations 2 and 3, and discharge the dissolved substances as soon as possible. Based on this, compared with Example 1, this embodiment adds a three-stage soft water recovery treatment of "Station 12 → Station 7 → Station 3 (Station 2)". On the one hand, the three-stage return water is used to save soft water replenishment. On the other hand, Station 7 is the second station after the alkali washing station, and its internal liquid pH value is relatively high. The return water mechanism of Station 7 → Station 3 (Station 2) is adopted to weaken the acidity of Station 3 (Station 2). After the silk cake washed in Stations 2 and 3 enters Station 4 for washing, the liquid pH in Station 3 meets the EDTA use requirements (i.e., the pH value is 4-6), and there is no need to add too much fresh soft water or sodium hydroxide to adjust the pH value in Station 3.

[0074] In summary, the inflow and outflow of soft water in the 2nd, 3rd, 6th, 7th, 8th, 11th, 12th and 13th stations can be shown in the following table:

[0075]

[0076]

[0077] That is, the fresh soft water addition ratio in the 2nd, 3rd, 6th, 7th, 8th, 11th, 12th and 13th stations can be set to 5:3:1:2:2:1:5:5; the fresh soft water addition, sewage discharge, return water inflow and return water outflow ratio in the 2nd station is 3:4:1:0; the fresh soft water addition, sewage discharge, return water inflow and return water outflow ratio in the 3rd station is 3:5:2:0; the fresh soft water addition, sewage discharge, return water inflow and return water outflow ratio in the 6th station is 1:5:4:0; the fresh soft water in the 7th station is The ratio of the amount of replenishment, the amount of sewage, the amount of return water inflow and the amount of return water outflow is 6:3:8:11; the ratio of the amount of fresh soft water replenishment, the amount of sewage, the amount of return water inflow and the amount of return water outflow in the 8th station is 2:2:1:2; the ratio of the amount of fresh soft water replenishment, the amount of sewage, the amount of return water inflow and the amount of return water outflow in the 11th station is 1:1:3:3; the ratio of the amount of fresh soft water replenishment, the amount of sewage, the amount of return water inflow and the amount of return water outflow in the 12th station is 15:4:0:11; the ratio of the amount of fresh soft water replenishment, the amount of sewage, the amount of return water inflow and the amount of return water outflow in the 13th station is 5:2:0:3. The ratio of the amount of fresh soft water replenishment and the amount of sewage in the other treatment stations can be adaptively set according to needs.

[0078] This technical solution has the following advantages over Example 1:

[0079] 1) Further improve the efficiency of water resource recycling. After adding the return pipe V15, two sections of three-stage soft water recovery and treatment channels "Station 12 → Station 7 → Station 3 (Station 2)" are formed. This makes the soft water reuse of the entire system more sufficient and further reduces the amount of fresh soft water added. In industrial production, the higher the degree of water resource recycling, the lower the production cost and the pressure on the environment. For example, through this multi-level return water mechanism, the system can maximize the use of used soft water while ensuring the cleaning effect. It is like a multi-level water resource reuse network, and every link plays a role in saving water resources.

[0080] 2) Optimize pH adjustment. Taking advantage of the high pH value of the liquid inside the 7th station, it is introduced into the 3rd station (the 2nd station) through the water return mechanism, which can weaken the acidity of the 3rd station (the 2nd station). In the cleaning process of viscose filaments, the control of pH value is very critical. For the 3rd station, its liquid pH meets the EDTA use requirements, which is an important condition to ensure that EDTA effectively complexes zinc ions. This water return mechanism avoids adding too much fresh soft water or sodium hydroxide to adjust the pH value in the 3rd station. This not only reduces the use of chemical reagents and reduces production costs, but also reduces potential problems such as water quality changes caused by adjusting the pH value. For example, if too much sodium hydroxide is added to adjust the pH value, it may cause the sodium ion concentration in the water to be too high, affecting the subsequent cleaning effect or the quality of the filaments.

[0081] 3) Improve the overall cleaning quality of the silk strips. After the silk cakes washed in the second and third stations enter the fourth station for washing, the pH of the liquid in the third station is effectively controlled, making the entire cleaning process more scientific and reasonable. The appropriate pH value can ensure that the chemical reagents at each cleaning station have the best cleaning effect. For example, under the appropriate pH environment, steps such as acid washing, alkali washing, and water washing can better remove impurities on the surface and inside of the silk strips, such as metal ions and sulfur, thereby improving the overall quality of the silk strips, including appearance quality (such as preventing white spots and yellowing) and physical properties (such as cohesion and strength).

[0082] Example 3

[0083] This embodiment discloses a viscose filament pressure washing system and a soft water utilization method thereof, as a basic implementation scheme of the present technical scheme, such as Figure 1 As shown, the viscose filament pressure washing system includes a soft water supply network, a soft water reuse network and 14 treatment stations arranged in sequence.

[0084] Among the 14 processing stations, each processing station is provided with a sewage pipe 1, and a sewage bottom valve 2 is connected to the sewage pipe 1. The first station is an acid washing station, which is used to react metal ions to form soluble metal sulfates and remove them. The third station is an EDTA (ethylenediaminetetraacetic acid) station, the fourth station (not shown) and the fifth station (not shown) are alkaline washing stations, the fourteenth station (not shown) is an oil station, and the second station and the sixth to thirteenth stations are all water washing stations, which are used to remove sulfur, sulfates, sulfides and washing liquids on the surface of the silk strips. The first station, the fourth station, the fifth station and the fourteenth station have their own opposing liquid replenishment pipelines and liquid circulation pipe network structures.

[0085] The soft water replenishing pipe network includes a main pipeline 3 and 10 soft water replenishing pipes 4. The main pipeline 3 is connected to the second station, the third station and the sixth to the thirteenth stations through the 10 soft water replenishing pipes 4 one by one. The 10 soft water replenishing pipes 4 are respectively connected with soft water replenishing valves 5.

[0086] The soft water recycling network includes return pipe I6, return pipe II8, return pipe III10, return pipe IV13, return pipe V15, return pipe VI18 and return pipe VII20. Return pipe I6 is connected from the 13th station to the 11th station, and a return valve I7 is connected to the return pipe I6. Return pipe II8 is connected from the 11th station to the 6th station, and a return valve II9 is ​​connected to the return pipe II8. Return pipe III10 is connected from the 12th station to the 7th station and the 8th station, and return valves III11 and IV12 are respectively provided in the return pipe III10 corresponding to the 7th station and the 8th station. Return pipe IV13 is connected from the 8th station to the 6th station, and a return valve V14 is connected to the return pipe IV13. The return pipe VI18 is connected from the 3rd station to the 2nd station, and the return pipe VII20 is connected from the 2nd station to the 1st station; the return pipe VI18 and the return pipe VII20 are respectively connected with a return valve VIII19 and a return valve IX21.

[0087] The return pipe V15 is connected from the 7th station to the 2nd station and the 3rd station; the return pipe V15 is provided with a return valve VI16 and a return valve VII17 corresponding to the 2nd station and the 3rd station respectively.

[0088] Therefore, in practical application, the soft water utilization method based on the above-mentioned viscose filament pressure washing system specifically includes the following steps:

[0089] S1, according to the structure of the viscose filament pressing and washing system, determine the function of each processing station in the viscose filament pressing and washing system.

[0090] S2, laying out the pipe network, that is, laying out the soft water supply pipe network and the soft water recycling pipe network according to the structure of the aforementioned viscose filament pressure washing system.

[0091] S3, close all sewage bottom valves 2 and return valves, open the soft water replenishing valves 5 on all soft water replenishing pipes 4, and inject fresh soft water into each treatment station through the soft water replenishing pipe 4 until the liquid level in each treatment station reaches 80% to 90% of its total capacity.

[0092] S4, adjust the opening of each soft water replenishing valve 5, the sewage bottom valve 2 and the return water valve, so that the viscose filament pressure washing system enters the station soft water circulation mode; in the process of station soft water circulation, the return water volume is controlled by each return water valve, and the soft water replenishing valve 5 and the sewage bottom valve 2 are cooperated to maintain the liquid level in each processing station at 75% to 95% of its own capacity.

[0093] In this technical solution, according to the structure of the viscose filament pressure washing system, in the station soft water circulation mode, there are five sections of three-level soft water recovery and treatment channels, namely "Station 13 → Station 11 → Station 6", "Station 12 → Station 8 → Station 6", "Station 12 → Station 7 → Station 3 (Station 2)" and "Station 3 → Station 2 → Station 1". Since a large amount of metal ions are dissolved after washing at Station 1, it is necessary to increase the soft water replenishment and sewage discharge at Stations 2 and 3, strengthen the fresh soft water replacement at Stations 2 and 3, and discharge the dissolved substances as soon as possible. Based on this, compared with Example 1, this embodiment adds a three-stage soft water recovery treatment of "Station 12 → Station 7 → Station 3 (Station 2)". On the one hand, the three-stage return water is used to save soft water replenishment. On the other hand, Station 7 is the second station after the alkali washing station, and its internal liquid pH value is relatively high. The return water mechanism of Station 7 → Station 3 (Station 2) is adopted to weaken the acidity of Station 3 (Station 2). After the silk cake washed in Stations 2 and 3 enters Station 4 for washing, the liquid pH in Station 3 meets the EDTA use requirements (i.e., the pH value is 4-6), and there is no need to add too much fresh soft water or sodium hydroxide to adjust the pH value in Station 3.

[0094] Furthermore, relative to Example 1, a three-stage soft water recovery and treatment channel of "Station 3 → Station 2 → Station 1" is added, which is characterized in that the sulfuric acid washing at Station 1 is strengthened, and the 2nd and 3rd stations before the alkaline washing at Station 4 and Station 5 are replaced with the water washing at Station 6 and Station 7 after the alkaline washing, and the pH is adjusted for the use of EDTA at Station 4 by returning water from Station 7 → Station 2 (Station 3), thereby realizing multifunctional utilization.

[0095] Furthermore, the 9th station is a water washing station, where more fresh soft water can be added to enhance the water washing of the silk cake at this station, so that the pH of the silk cake can be quickly reduced to near neutral, which is conducive to the subsequent oiling at the 14th station. The other 10 stations only add a small amount of soft water to maintain the liquid level, which plays a role of circulating water washing.

[0096] Technical requirements:

[0097] 1) pH control requirements. The pH of the EDTA station at the 3rd station is in the range of 4 to 6, which meets the requirements of complexing zinc ions. The pH of the water washing station at the 12th station is in the range of 7.5 to 8.5. A pH higher than 8.5 will lead to poor oiling effect at the 14th station. A pH lower than 7.5 requires an increase in the amount of fresh soft water. Among them, for the 12th station, if the alkali concentration control in the front is too high, it will cause the pH in the back to be too high. Therefore, restricting the 12th station is conducive to fault tolerance, convenient and timely response, and prevents direct entry into the 14th station.

[0098] 2) Washing liquid level control requirements in each processing station: 75%-95%

[0099] 3) Fresh soft water requirements: temperature 40-45℃, pH 7-8, iron content ≤ 0.03mg / L, conductivity < 500us / cm. In summary, the inflow and outflow of soft water in stations 1 to 14 can be shown in the following table:

[0100]

[0101]

[0102] That is, the ratio of fresh soft water addition in the 1st to 14th stations can be set to 0:15:9:3:6:6:9:3:3:15:15:0. The ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 1st station is 0:0:2:0, and 2 parts of the return water inflow are used to compensate for the liquid level loss in the 1st station. The ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 2nd station is 15:24:11:2. The ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 3rd station is 3:3:2:2. The ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 6th station is 1:5:4:0. The ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 7th station is 6:3:8:11. The ratio of fresh soft water addition, sewage discharge, backwater inflow and backwater outflow in the 8th station is 2:2:1:2. The ratio of fresh soft water addition, sewage discharge, backwater inflow and backwater outflow in the 9th station is 9:9:0:0. The ratio of fresh soft water addition, sewage discharge, backwater inflow and backwater outflow in the 10th station is 3:0:0:0. The ratio of fresh soft water addition, sewage discharge, backwater inflow and backwater outflow in the 11th station is 1:1:3:3. The ratio of fresh soft water addition, sewage discharge, backwater inflow and backwater outflow in the 12th station is 15:4:0:11. The ratio of fresh soft water addition, sewage discharge, backwater inflow and backwater outflow in the 13th station is 5:2:0:3. The ratio of fresh soft water addition, sewage discharge, return water inflow and return water outflow in the 14th station is 0:0:0:0.

[0103] Among them, within the working temperature range of EDTA (ethylenediaminetetraacetic acid) (40-60°C), the pH control range of EDTA complexed zinc ions is 4-6. After acid washing in the first station and alkaline washing in the fourth and fifth stations, the silk cake contains a large amount of acidic or alkaline washing liquid. After entering the next station, the washing liquid is replaced. The pH of the washing liquid in the seventh station is generally 11-11.5, and the pH of the washing liquid in the second station is generally 2.4-2.8. By using the seventh station → the second station (the third station), the washing liquid with a higher pH value is recycled to neutralize the washing environment with a lower pH value in the previous station, so that the pH value of the washing liquid after entering the fourth station is stabilized within the EDTA working range. Compared with the method of neutralizing by adding fresh soft water or directly adding sodium hydroxide, this scheme directly uses the washing liquid with a higher pH value at the back end to reduce the addition of soft water.

Claims

1. A viscose filament pressure washing system, characterized in that: It includes a soft water replenishment network, a soft water reuse network and 14 treatment stations arranged in sequence; Among the 14 treatment stations, each treatment station is provided with a sewage pipe (1), and a sewage bottom valve (2) is connected to the sewage pipe (1); the first station is a pickling station, the third station is an EDTA station, the fourth station and the fifth station are alkali washing stations, the fourteenth station is an oil agent station, and the second station and stations 6 to 13 are all water washing stations; The soft water replenishment pipe network comprises a main pipe (3) and 10 soft water replenishment pipes (4); the main pipe (3) is connected to the second station, the third station, and the sixth to the thirteenth stations in a one-to-one correspondence through the 10 soft water replenishment pipes (4); and the 10 soft water replenishment pipes (4) are respectively connected to soft water replenishment valves (5); The soft water recycling network comprises a return pipe I (6), a return pipe II (8), a return pipe III (10), and a return pipe IV (13); the return pipe I (6) is connected from the 13th station to the 11th station, and a return valve I (7) is connected to the return pipe I (6); the return pipe II (8) is connected from the 11th station to the 6th station, and a return valve II (9) is connected to the return pipe II (8); the return pipe III (10) is connected from the 12th station to the 7th station and the 8th station, and a return valve III (11) and a return valve IV (12) are respectively provided in the return pipe III (10) corresponding to the 7th station and the 8th station; the return pipe IV (13) is connected from the 8th station to the 6th station, and a return valve V (14) is connected to the return pipe IV (13).

2. A viscose filament pressure washing system as claimed in claim 1, characterized in that: The soft water recycling network further comprises a return pipe V (15), which is connected from the seventh station to the second station and the third station; a return valve VI (16) and a return valve VII (17) are respectively arranged in the return pipe V (15) corresponding to the second station and the third station.

3. A viscose filament pressure washing system as claimed in claim 1, characterized in that: The soft water recycling network further comprises a return pipe VI (18) and a return pipe VII (20); the return pipe VI (18) is connected from the third station to the second station, and the return pipe VII (20) is connected from the second station to the first station; the return pipe VI (18) and the return pipe VII (20) are respectively connected to a return valve VIII (19) and a return valve IX (21).

4. A soft water utilization method based on a viscose filament pressure washing system, characterized in that: The following steps are involved: S1, determine the function of each processing station in the viscose filament pressing and washing system, that is, the viscose filament pressing and washing system includes 14 processing stations, of which the first station is an acid washing station, the third station is an EDTA station, the fourth and fifth stations are alkali washing stations, the fourteenth station is an oil station, and the remaining nine processing stations are water washing stations; S2, laying out a pipe network, including: configuring soft water replenishment pipes (4) and sewage pipes (1) for all treatment stations, and connecting each treatment station to the main pipe (3) via the soft water replenishment pipe (4); setting a return pipe I (6) with a return valve I (7) to connect from the 13th station to the 11th station; setting a return pipe II (8) with a return valve II (9) to connect from the 11th station to the 6th station; setting a return pipe III (10) with a return valve III (11) and a return valve IV (12) to connect from the 12th station to the 7th station and the 8th station; setting a return pipe IV (13) with a return valve V (14) to connect from the 8th station to the 6th station; S3, close all sewage bottom valves (2) and return valves, open the soft water replenishing valves (5) on all soft water replenishing pipes (4), and inject fresh soft water into each treatment station through the soft water replenishing pipe (4) until the liquid level in each treatment station reaches 80% to 90% of its total capacity; S4, adjusting the opening of each soft water replenishing valve (5), the sewage bottom valve (2) and the return water valve, so that the viscose filament pressure washing system enters the station soft water circulation mode; during the station soft water circulation process, the return water volume is controlled by each return water valve, and the soft water replenishing valve (5) and the sewage bottom valve (2) are coordinated to maintain the liquid level in each treatment station at 75% to 95% of its own capacity.

5. A method for utilizing soft water in a viscose filament pressure washing system as claimed in claim 4, characterized in that: In step S4, during the station soft water circulation process, the ratio of fresh soft water added to the 14 treatment stations in the same time period is 0:15:9:3:6:6:9:3:3:15:15:

0.

6. A method for utilizing soft water in a viscose filament pressure washing system as claimed in claim 5, characterized in that: In step S4, during the soft water circulation at the stations, the ratio of the soft water addition, sewage discharge and return water outflow in the 13th station is 5:2:3; the ratio of the soft water addition, sewage discharge, return water inflow and return water outflow in the 11th station is 1:1:3:

3.

7. A method for utilizing soft water in a viscose filament pressure washing system as claimed in claim 5, characterized in that: In step S4, during the soft water circulation at the stations, the ratio of the soft water addition, sewage discharge and return water outflow in the 12th station is 15:4:11; the ratio of the soft water addition, sewage discharge, return water inflow and return water outflow in the 8th station is 2:2:1:

1.

8. A method for utilizing soft water in a viscose filament pressure washing system as claimed in claim 5, characterized in that: In the step S2, laying the pipe network further includes providing a return pipe V (15) with a return valve VI (16) and a return valve VII (17), and connecting the return pipe V (15) from the seventh station to the second station and the third station.

9. A method for utilizing soft water in a viscose filament pressure washing system as claimed in claim 8, characterized in that: In step S4, during the soft water circulation at the stations, the ratio of soft water addition, sewage discharge, return water inflow and return water outflow in the 7th station is 6:3:8:11; among them, the ratio of soft water return from the 7th station to the 3rd and 2nd stations is 6:

5.

10. A method for utilizing soft water in a viscose filament pressure washing system as claimed in claim 8, characterized in that: In step S2, laying out the pipe network further includes providing a return pipe VI (18) with a return valve VIII (19) and a return pipe VII (20) with a return valve IX (21), connecting the return pipe VI (18) from the third station to the second station, and connecting the return pipe VII (20) from the second station to the first station.

11. A method for utilizing soft water in a viscose filament pressure washing system as claimed in claim 10, characterized in that: In step S4, during the soft water circulation process at the stations, the ratio of soft water addition, sewage discharge, return water inflow and return water outflow at the third station is 3:3:2:2; the ratio of soft water addition, sewage discharge, return water inflow and return water outflow at the second station is 15:24:11:2.

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