System and process for cotton material online recovery and neutral water regeneration in nitrocotton production process

Abstract

The invention provides a cotton material online recovery and neutral water regeneration system and process in a nitrocotton production process. The system comprises a vertical flow precipitation recovery tower, a precision filter and an efficient concentration filter which are connected through pipelines and pump valves, the vertical flow precipitation recovery tower receives and treats the cotton material-containing neutral water to obtain suspended fiber-containing neutral water and high-concentration nitrocotton, the suspended fiber-containing neutral water flows into the precision filter, and the high-concentration nitrocotton returns to the current batch of nitrocotton production and is treated into high-quality nitrocotton; suspended fibers in the suspended fiber-containing neutral water are filtered out by the precision filter and conveyed to the efficient concentration filter, and high-quality neutral water formed after filtration is recycled for a nitrocotton production process; the suspended fibers are concentrated into low-concentration nitrocotton by the efficient concentration filter, the generated neutral water containing the suspended fibers is returned to the precision filter, and the low-concentration nitrocotton is returned to the next batch of nitrocotton production and is treated into high-quality nitrocotton. Therefore, efficient recovery treatment of the cotton material and the neutral water is completed.

Description

Technical Field

[0001] This invention relates to the field of nitrocellulose production technology, and in particular to an online cotton material recycling and neutral water regeneration system and process for nitrocellulose production. Background Technology

[0002] In nitrocellulose production lines, cotton concentrate concentration mainly relies on inclined screens, false bottoms, and fiber recovery machines to separate water and cotton. A large amount of cotton is discharged through the screen gaps, resulting in significant material loss. To ensure product yield, the discharged neutral water is periodically recycled and packaged as low-quality nitrocellulose after natural sedimentation, making recycling economically unfeasible. Simultaneously, a large amount of unsedimented cotton enters the neutral water and wastewater, ultimately becoming sludge. This wastes nitrocellulose and increases the difficulty of wastewater treatment and sludge disposal costs. Summary of the Invention

[0003] Based on the above, the purpose of this invention is to provide an online cotton material recycling and neutral water regeneration system and process for nitrocellulose production. This solution utilizes multi-stage coupled physical separation technology and a fully automated control system to achieve online and automatic recycling of nitrocellulose material from production wastewater that can be reused as a positive product. Simultaneously, it produces clean, neutral water with extremely low suspended solids content for reuse in the production line, forming a closed-loop cycle of materials and water. This significantly improves product yield, reduces water consumption, and lowers environmental treatment costs.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] In a first aspect, the present invention provides an online cotton material recovery and neutral water regeneration system for the nitrocellulose production process, comprising a vertical flow sedimentation recovery tower, a precision filter, and a high-efficiency concentration filter connected by pipes and pumps / valve.

[0006] The vertical flow sedimentation and recovery tower receives and processes neutral water containing cotton to obtain neutral water containing suspended fibers and high-concentration nitrocellulose. The neutral water containing suspended fibers flows into the precision filter, and the high-concentration nitrocellulose is returned to the production of the current batch of nitrocellulose and processed into high-quality nitrocellulose.

[0007] The precision filter removes suspended fibers from the neutral water containing suspended fibers and conveys it to the high-efficiency concentration filter. The high-quality neutral water formed after filtration is recycled for use in the nitrocellulose production process.

[0008] The high-efficiency concentration filter concentrates the suspended fibers into low-concentration nitrocellulose. This process also generates neutral water containing the suspended fibers, which is returned to the precision filter. The low-concentration nitrocellulose is then returned to the next batch of nitrocellulose production and processed into high-quality nitrocellulose.

[0009] In one alternative embodiment, a central water inlet pipe and a first agitator are provided at the top of the vertical flow sedimentation and recovery tower. The end of the central water inlet pipe and the working end of the first agitator are both located inside the vertical flow sedimentation and recovery tower, and a reflector plate is provided below the end of the central water inlet pipe.

[0010] The top side of the vertical flow sedimentation and recovery tower is provided with an outlet weir plate and an overflow outlet. The side of the vertical flow sedimentation and recovery tower is also provided with multiple outlet pipes. The overflow outlet and outlet pipes are connected to the precision filter through pipes.

[0011] The bottom of the vertical flow sedimentation and recovery tower is equipped with a cotton storage hopper and a material level switch. The end of the cotton storage hopper is connected to a screw conveyor and a first suction pump. After the material level switch detects that the high-concentration nitrocellulose at the bottom of the cotton storage hopper has reached a set height, it starts the screw conveyor and the first suction pump to transport the high-concentration nitrocellulose to the production of the current batch of nitrocellulose and process it into high-quality nitrocellulose.

[0012] In one alternative embodiment, the precision filter is provided with a rotating shaft, and the rotating shaft is provided with a plurality of circular filter discs along its length. Each filter disc is composed of a plurality of fan-shaped filter plates. The filter plates are detachably inserted into the mounting port of the rotating shaft. Filter cloth is provided on the filter plates, and the thickness of the filter cloth and the filter plates are equal.

[0013] The precision filter is also provided with multiple scrapers. The scrapers are located at both ends of the rotating shaft and between two adjacent filter discs. The scrapers are fixedly installed on the inner wall of the precision filter and the edges of the scrapers are attached to the filter cloth. The scrapers are provided with suction holes. Half of the scrapers are connected to the second suction pump through the suction holes, and the other half of the scrapers are connected to the third suction pump through the suction holes.

[0014] The precision filter has a first inlet and an inlet water distribution trough at its top. The neutral water containing suspended fibers generated by the vertical flow sedimentation and recovery tower and the high-efficiency thickening filter flows into the precision filter through the first inlet and is then evenly distributed inside the precision filter through the inlet water distribution trough.

[0015] The precision filter also includes a first outlet, a drive device, and a level gauge. The filter cloth filters the neutral water containing suspended fibers into high-quality neutral water, which flows out from the first outlet. The suspended fibers form a cotton layer on the filter cloth. As the cotton layer blocks the filter cloth, the flow rate of the neutral water containing suspended fibers slows down, and the liquid level in the precision filter rises continuously. When the level gauge detects that the liquid level has risen to a set height, the drive device drives the filter disc and the filter cloth to rotate. The scraper remains stationary and scrapes off the cotton layer on the surface of the filter cloth. The second and third suction pumps start, sucking the cotton layer into the pipeline through the suction hole and transporting it to the high-efficiency concentrator.

[0016] In one alternative embodiment, the precision filter is further provided with a bottom suction pipe and a first to an eighth solenoid valve. The first solenoid valve is used to connect one half of the scraper and the second suction pump, and the fifth solenoid valve is used to connect the other half of the scraper and the third suction pump. One end of the second to fourth solenoid valves is connected to the bottom suction pipe, and the other end is connected to the second suction pump. One end of the sixth to eighth solenoid valves is connected to the bottom suction pipe, and the other end is connected to the third suction pump.

[0017] In one alternative embodiment, the high-efficiency concentrator includes a second stirrer, a fan-shaped ceramic filter plate, a concentration meter, a fourth suction pump, and a fifth suction pump. The second stirrer operates continuously, the fan-shaped ceramic filter plate traps most of the suspended fibers within the filter pores, forming neutral water containing the suspended fibers, the fourth suction pump delivers the neutral water containing the suspended fibers to the precision filter, and when the concentration meter detects that the concentration of the suspended fibers reaches a set value to form low-concentration nitrocellulose, the fifth suction pump returns the low-concentration nitrocellulose to the cotton feed tank for the next batch of nitrocellulose production, where it is processed into high-quality nitrocellulose.

[0018] In one alternative embodiment, the high-efficiency thickener filter further includes a cleaning pump for rapidly flushing the interior of the high-efficiency thickener filter.

[0019] In one alternative embodiment, the high-efficiency concentration filter further includes a siphon tank, which is connected to the precision filter via a one-way valve and a pipeline. The fourth suction pump draws the neutral water containing suspended fibers into the siphon tank. When the liquid level in the siphon tank reaches a certain height, the one-way valve automatically opens to deliver the neutral water containing suspended fibers to the precision filter.

[0020] In one alternative embodiment, the high-efficiency concentrator further includes an ultrasonic cleaning device, which is activated to clean the filter pores of the sector-shaped ceramic filter plate when the operating frequency of the fifth suction pump increases to a set value.

[0021] In an alternative embodiment, a PLC control system is also included, which is electrically connected to the electrical components that need to be controlled in the online cotton material recycling and neutral water regeneration system of the nitrocellulose production process.

[0022] In a second aspect, the present invention provides an online cotton material recycling and neutral water regeneration process for nitrocellulose production, applied to the system described in any of the above claims, comprising the following steps:

[0023] The neutral water containing cotton material generated from the nitrocellulose production line is introduced into the vertical flow sedimentation and recovery tower for sedimentation treatment, and the neutral water containing suspended fibers and the high-concentration nitrocellulose are separated.

[0024] The high-concentration nitrocellulose is returned to the production of the current batch of nitrocellulose and processed into high-quality nitrocellulose.

[0025] The neutral water containing suspended fibers is introduced into the precision filter for filtration to obtain the high-quality neutral water and the suspended fibers.

[0026] The high-quality neutral water is reused in the nitrocellulose production process;

[0027] The suspended fibers obtained from the precision filter are introduced into the high-efficiency thickener filter for concentration and dehydration. The cotton concentration is monitored in real time. When the concentration reaches or exceeds a set value, the concentrated low-concentration nitrocellulose is returned to the cotton feed tank for the next batch of nitrocellulose production, and processed into high-quality nitrocellulose.

[0028] The beneficial effects of this invention are as follows:

[0029] (1) By recycling online and reusing cotton as a genuine product, the product yield of nitrocellulose is directly improved, the "waste" in the traditional process is transformed into a high-value product, the loss caused by material loss is avoided, and the resource utilization rate and economic benefits are improved.

[0030] (2) Through deep purification, the neutral water meets the high standard of reuse requirements, which greatly reduces the amount of fresh water taken out and the total amount of wastewater discharged, significantly reduces the water consumption per ton of product, and achieves deep conservation and recycling of production water.

[0031] (3) Significantly reduce solid pollutants (nitrocellulose fiber) entering the end-of-pipe wastewater treatment system from the source, thereby reducing the load of subsequent biochemical treatment, reducing sludge production and disposal costs, and lowering environmental protection operation costs.

[0032] (4) The entire set of equipment is centrally controlled by PLC, which is stable and reliable in operation, reduces the intensity of manual operation and human error, improves the refinement and intelligence of production management, and enhances the level of production automation and intelligence. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0034] Figure 1 This is a flowchart illustrating the process provided in an embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram of the vertical flow sedimentation and recovery tower structure provided in an embodiment of the present invention;

[0036] Figure 3 This is a three-dimensional structural schematic diagram of the precision filter provided in an embodiment of the present invention;

[0037] Figure 4 This is a vertical sectional view along the length of the precision filter provided in an embodiment of the present invention;

[0038] Figure 5 This is a side view of a precision filter provided in an embodiment of the present invention;

[0039] Figure 6 This is a partial structural diagram of the filter disc and scraper inside the precision filter provided in an embodiment of the present invention;

[0040] Figure 7 This is a three-dimensional structural schematic diagram of the high-efficiency concentration filter provided in an embodiment of the present invention;

[0041] Figure 8 This is a top view of a high-efficiency concentration filter provided in an embodiment of the present invention.

[0042] Figure label:

[0043] 1-Vertical flow sedimentation and recovery tower; 101-Central inlet pipe; 102-First agitator; 103-Reflector plate; 104-Outlet weir plate; 105-Overflow outlet; 106-Outlet pipe; 107-Cotton storage hopper; 108-Material level switch; 109-Screw conveyor; 110-First suction pump;

[0044] 2-Precision filter; 201-Rotating shaft; 202-Filter disc; 203-Filter plate; 204-Mounting port; 205-Filter cloth; 206-Scraper; 207-Suction hole; 208-Second suction pump; 209-Third suction pump; 210-First inlet; 211-Inlet water trough; 212-First outlet; 213-Drive device; 214-Level gauge; 215-Bottom suction pipe; 221-First solenoid valve; 222-Second solenoid valve; 223-Third solenoid valve; 224-Fourth solenoid valve; 225-Fifth solenoid valve; 226-Sixth solenoid valve; 227-Seventh solenoid valve; 228-Eighth solenoid valve;

[0045] 3-High-efficiency thickening filter; 301-Second stirrer; 302-Fan-shaped ceramic filter plate; 303-Concentration meter; 304-Fourth suction pump; 305-Fifth suction pump; 306-Cleaning pump; 307-Siphon tank; 308-Ultrasonic cleaning device; 309-Second water inlet; 310-Second water outlet. Detailed Implementation

[0046] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0047] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0048] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0049] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used solely for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In the description of the present invention, unless otherwise stated, "a plurality of" means two or more. Furthermore, the terms "first" and "second" are merely used for descriptive distinction and have no special meaning.

[0050] This invention provides an online cotton material recovery and neutral water regeneration system for the nitrocellulose production process. The "neutral water" referred to in this invention specifically refers to the process wastewater generated during nitrocellulose production, with a pH value of 6.5–7.5 and containing suspended nitrocellulose material. The specific structure of the system is as follows: Figures 1 to 7 As shown, it includes a vertical flow sedimentation and recovery tower 1, a precision filter 2, and a high-efficiency concentrator 3 connected by pipes and pumps / valve.

[0051] Vertical flow sedimentation recovery tower 1 receives and processes neutral water containing cotton material to obtain neutral water containing suspended fibers and high-concentration nitrocellulose. The neutral water containing suspended fibers flows into precision filter 2, and the high-concentration nitrocellulose is returned to the production of the current batch of nitrocellulose and processed into high-quality nitrocellulose.

[0052] Precision filter 2 filters out suspended fibers from neutral water containing suspended fibers and conveys it to high-efficiency thickening filter 3. The high-quality neutral water formed after filtration is recycled for use in the nitrocellulose production process.

[0053] The high-efficiency thickening filter 3 concentrates the suspended fibers into low-concentration nitrocellulose. This process also generates neutral water containing suspended fibers, which is returned to the precision filter 2. The low-concentration nitrocellulose is returned to the next batch of nitrocellulose production and is processed into high-quality nitrocellulose.

[0054] Preferably, such as Figure 2 As shown, a central water inlet pipe 101 and a first agitator 102 are provided at the top of the vertical flow sedimentation and recovery tower 1. The end of the central water inlet pipe 101 and the working end of the first agitator 102 are both located inside the vertical flow sedimentation and recovery tower 1. A reflector plate 103 is provided below the end of the central water inlet pipe 101. The reflector plate 103 is umbrella-shaped and is used to eliminate the impact of the incoming water and achieve uniform water distribution. Due to the low fluidity of the nitrocellulose fiber itself, the first agitator 103 is required to mix the nitrocellulose fiber attached to the inner wall of the vertical flow sedimentation and recovery tower 1 with neutral water to form a suspension. The suspension is then pumped out of the vertical flow sedimentation and recovery tower by the screw conveyor 109 and the first suction pump 110 to form a high-concentration nitrocellulose with a concentration of about 13%.

[0055] Furthermore, the top side of the vertical flow sedimentation and recovery tower 1 is provided with an outlet weir plate 104 and an overflow outlet 105. The side of the vertical flow sedimentation and recovery tower 1 is also provided with multiple outlet pipes 106. The overflow outlet 105 and the outlet pipes 106 are connected to the precision filter 2 through pipes to transport the neutral water containing suspended fibers in the vertical flow sedimentation and recovery tower 1.

[0056] Furthermore, the bottom of the vertical flow sedimentation recovery tower 1 is equipped with a cotton storage hopper 107 and a material level switch 108. The end of the cotton storage hopper 107 is connected to a screw conveyor 109 and a first suction pump 110. After the material level switch 108 detects that the high-concentration nitrocellulose at the bottom of the cotton storage hopper 107 has reached the set height, it starts the screw conveyor 109 and the first suction pump 110 to transport the high-concentration nitrocellulose to the production of the current batch of nitrocellulose and process it into high-quality nitrocellulose.

[0057] Preferably, such as Figures 3 to 6 As shown, a rotating shaft 201 is provided inside the precision filter 2. Multiple circular filter discs 202 are arranged along the length of the rotating shaft 201. Each filter disc 202 is composed of multiple fan-shaped filter plates 203. The filter plates 203 are detachably inserted into the mounting port 204 of the rotating shaft 201. Filter cloth 205 is provided on the filter plates 203, and the thickness of the filter cloth 205 and the filter plate 203 is equal.

[0058] The precision filter 2 is also equipped with multiple scrapers 206. The scrapers 206 are located at both ends of the rotating shaft 201 and in the middle of two adjacent filter discs 202. The scrapers 206 are fixedly installed on the inner wall of the precision filter 2 and the edges of the scrapers 206 are in contact with the filter cloth 205. The scrapers 206 at both ends only process the filter cloth 205 at both ends, while the scrapers 206 in the middle of the two adjacent filter discs 202 can process both filter cloths at the same time. The scrapers 206 are provided with suction holes 207. Half of the scrapers 206 are connected to the second suction pump 208 through the suction holes 207, and the other half of the scrapers 206 are connected to the third suction pump 209 through the suction holes 207.

[0059] The precision filter 2 has a first inlet 210 and an inlet water distribution tank 211 at the top. The neutral water containing suspended fibers generated by the vertical flow sedimentation and recovery tower 1 and the high-efficiency thickening filter 3 flows into the precision filter 2 through the first inlet 210 and is then evenly distributed inside the precision filter 2 through the inlet water distribution tank 211.

[0060] Specifically, the precision filter 2 also includes a first outlet 212, a drive device 213, and a level gauge 214. The filter cloth 205 filters the neutral water containing suspended fibers into high-quality neutral water, which flows out from the first outlet 212. The suspended fibers form a cotton layer on the filter cloth 205. As the cotton layer blocks the filter cloth 205, the flow rate of the neutral water containing suspended fibers slows down, and the liquid level in the precision filter 2 continues to rise. When the level gauge 214 detects that the liquid level has risen to a set height, the drive device 213 drives the filter disc 202 and the filter cloth 205 to rotate. The scraper 206 remains stationary and scrapes off the cotton layer on the surface of the filter cloth 205. The second suction pump 208 and the third suction pump 209 are started, and the cotton layer is sucked into the pipeline through the suction hole 207 and transported to the high-efficiency thickening filter 3.

[0061] Furthermore, the precision filter 2 is also equipped with a bottom suction pipe 215 and first to eighth solenoid valves. The first solenoid valve 221 is used to connect half of the scraper 206 and the second suction pump 208, and the fifth solenoid valve 225 is used to connect the other half of the scraper 206 and the third suction pump 209. The second to fourth solenoid valves are connected at one end to the bottom suction pipe 215 and at the other end to the second suction pump 208. The sixth to eighth solenoid valves are connected at one end to the bottom suction pipe 215 and at the other end to the third suction pump 209. When the drive unit 213 drives the filter disc 202 and filter cloth 205 to rotate, and the scraper 206 remains stationary while scraping off the cotton layer on the surface of the filter cloth 205, the first solenoid valve 221 and the fifth solenoid valve 225 open, while the second to fourth solenoid valves and the sixth to eighth solenoid valves close. Most of the nitrocellulose fibers are transported to the high-efficiency thickening filter 3 by the second suction pump 208 and the third suction pump 209. At this time, some nitrocellulose fibers still settle to the bottom area of ​​the precision filter 2 and need to be processed periodically through the bottom suction pipe 215. During bottom suction treatment, the first solenoid valve 221 and the fifth solenoid valve 225 close, while the second to fourth solenoid valves and the sixth to eighth solenoid valves open. The second suction pump 208 and the third suction pump 209 transport the bottom nitrocellulose fibers to the high-efficiency thickening filter 3 through the bottom suction pipe 215, further improving the recovery rate.

[0062] Preferably, such as Figure 7 and Figure 8As shown, the high-efficiency concentrator filter 3 includes a second stirrer 301, a fan-shaped ceramic filter plate 302, a concentration meter 303, a fourth suction pump 304, and a fifth suction pump 305. The second inlet 309 receives suspended fibers. The second stirrer 301 operates continuously. The fan-shaped ceramic filter plate 302 traps most of the suspended fibers in the filter holes, forming neutral water containing suspended fibers. The fourth suction pump 304 delivers the neutral water containing suspended fibers to the precision filter 2 through the second outlet 310. When the concentration meter 303 detects that the concentration of suspended fibers has reached a set value (about 5%) and low-concentration nitrocellulose has been formed, the fifth suction pump 305 returns the low-concentration nitrocellulose to the cotton feed tank for the next batch of nitrocellulose production, where it is processed into high-quality nitrocellulose.

[0063] Furthermore, the high-efficiency thickener filter 3 also includes a cleaning pump 306, which is used to quickly flush the inside of the high-efficiency thickener filter 3 when switching between different production lines.

[0064] Furthermore, the high-efficiency thickening filter 3 also includes a siphon tank 307, which is connected to the precision filter 2 via a one-way valve and a pipeline. The fourth suction pump 304 draws the neutral water containing suspended fibers into the siphon tank 307. When the liquid level in the siphon tank 307 reaches a certain height, the one-way valve automatically opens to deliver the neutral water containing suspended fibers to the precision filter 2.

[0065] Furthermore, the high-efficiency concentrator 3 also includes an ultrasonic cleaning device 308. When the operating frequency of the fifth suction pump 305 increases to a set value, the ultrasonic cleaning device 308 is activated to clean the filter holes of the fan-shaped ceramic filter plate 302, ensuring that the filtration function of the high-efficiency concentrator 3 continues to function.

[0066] Preferably, this application also includes a PLC control system, which is electrically connected to the electrical components that need to be controlled in the online cotton material recycling and neutral water regeneration system of the nitrocellulose production process. The electrical components specifically include a first agitator 102, a material level switch 108, a screw conveyor 109, a first suction pump 110, a second suction pump 208, a third suction pump 209, a drive device 213, a level gauge 214, first to eighth solenoid valves, a second agitator 301, a concentration meter 302, a fourth suction pump 304, a fifth suction pump 305, a cleaning pump 306, and an ultrasonic cleaning device 308.

[0067] This application also provides an online cotton material recycling and neutral water regeneration process for nitrocellulose production, applicable to any of the above systems, including the following steps:

[0068] The neutral water containing cotton produced by the nitrocellulose production line is introduced into the vertical flow sedimentation and recovery tower 1 for sedimentation treatment, and the neutral water containing suspended fibers and high-concentration nitrocellulose are separated.

[0069] High-concentration nitrocellulose is returned to the production of the current batch of nitrocellulose and processed into high-quality nitrocellulose.

[0070] Neutral water containing suspended fibers is introduced into precision filter 2 for filtration to obtain high-quality neutral water and suspended fibers.

[0071] High-quality neutral water is reused in the nitrocellulose production process;

[0072] The suspended fibers obtained from the precision filter 2 are introduced into the high-efficiency thickener filter 3 for concentration and dehydration. The cotton concentration is monitored in real time. When the concentration reaches or exceeds the set value, the concentrated low-concentration nitrocellulose is returned to the cotton material tank for the next batch of nitrocellulose production and processed into high-quality nitrocellulose.

[0073] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0074] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A system for online cotton material recycling and neutral water regeneration in the nitrocellulose production process, characterized in that, This includes vertical flow sedimentation and recovery towers, precision filters, and high-efficiency concentration filters connected by pipes and pumps; The vertical flow sedimentation and recovery tower receives and processes neutral water containing cotton to obtain neutral water containing suspended fibers and high-concentration nitrocellulose. The neutral water containing suspended fibers flows into the precision filter, and the high-concentration nitrocellulose is returned to the production of the current batch of nitrocellulose and processed into high-quality nitrocellulose. The precision filter removes suspended fibers from the neutral water containing suspended fibers and conveys it to the high-efficiency concentration filter. The high-quality neutral water formed after filtration is recycled for use in the nitrocellulose production process. The high-efficiency concentration filter concentrates the suspended fibers into low-concentration nitrocellulose. This process also generates neutral water containing the suspended fibers, which is returned to the precision filter. The low-concentration nitrocellulose is then returned to the next batch of nitrocellulose production and processed into high-quality nitrocellulose.

2. The system according to claim 1, characterized in that, The top of the vertical flow sedimentation and recovery tower is equipped with a central water inlet pipe and a first agitator. The end of the central water inlet pipe and the working end of the first agitator are both located inside the vertical flow sedimentation and recovery tower, and a reflector plate is provided below the end of the central water inlet pipe. The top side of the vertical flow sedimentation and recovery tower is provided with an outlet weir plate and an overflow outlet. The side of the vertical flow sedimentation and recovery tower is also provided with multiple outlet pipes. The overflow outlet and outlet pipes are connected to the precision filter through pipes. The bottom of the vertical flow sedimentation and recovery tower is equipped with a cotton storage hopper and a material level switch. The end of the cotton storage hopper is connected to a screw conveyor and a first suction pump. After the material level switch detects that the high-concentration nitrocellulose at the bottom of the cotton storage hopper has reached a set height, it starts the screw conveyor and the first suction pump to transport the high-concentration nitrocellulose to the production of the current batch of nitrocellulose and process it into high-quality nitrocellulose.

3. The system according to claim 1, characterized in that, The precision filter is provided with a rotating shaft, and multiple circular filter discs are arranged along the length of the rotating shaft. Each filter disc is composed of multiple fan-shaped filter plates. The filter plates are detachably inserted into the mounting port of the rotating shaft. Filter cloth is provided on the filter plates, and the thickness of the filter cloth and the filter plates are equal. The precision filter is also provided with multiple scrapers. The scrapers are located at both ends of the rotating shaft and between two adjacent filter discs. The scrapers are fixedly installed on the inner wall of the precision filter and the edges of the scrapers are attached to the filter cloth. The scrapers are provided with suction holes. Half of the scrapers are connected to the second suction pump through the suction holes, and the other half of the scrapers are connected to the third suction pump through the suction holes. The precision filter has a first inlet and an inlet water distribution trough at its top. The neutral water containing suspended fibers generated by the vertical flow sedimentation and recovery tower and the high-efficiency thickening filter flows into the precision filter through the first inlet and is then evenly distributed inside the precision filter through the inlet water distribution trough. The precision filter also includes a first outlet, a drive device, and a level gauge. The filter cloth filters the neutral water containing suspended fibers into high-quality neutral water, which flows out from the first outlet. The suspended fibers form a cotton layer on the filter cloth. As the cotton layer blocks the filter cloth, the flow rate of the neutral water containing suspended fibers slows down, and the liquid level in the precision filter rises continuously. When the level gauge detects that the liquid level has risen to a set height, the drive device drives the filter disc and the filter cloth to rotate. The scraper remains stationary and scrapes off the cotton layer on the surface of the filter cloth. The second and third suction pumps start, sucking the cotton layer into the pipeline through the suction hole and transporting it to the high-efficiency concentrator.

4. The system according to claim 3, characterized in that, The precision filter is also equipped with a bottom suction pipe and first to eighth solenoid valves. The first solenoid valve is used to connect one half of the scraper and the second suction pump, and the fifth solenoid valve is used to connect the other half of the scraper and the third suction pump. One end of the second to fourth solenoid valves is connected to the bottom suction pipe and the other end is connected to the second suction pump. One end of the sixth to eighth solenoid valves is connected to the bottom suction pipe and the other end is connected to the third suction pump.

5. The system according to claim 1, characterized in that, The high-efficiency concentration filter includes a second stirrer, a fan-shaped ceramic filter plate, a concentration meter, a fourth suction pump, and a fifth suction pump. The second stirrer operates continuously. The fan-shaped ceramic filter plate traps most of the suspended fibers in the filter pores, forming neutral water containing suspended fibers. The fourth suction pump delivers the neutral water containing suspended fibers to the precision filter. When the concentration meter detects that the concentration of the suspended fibers has reached a set value to form low-concentration nitrocellulose, the fifth suction pump returns the low-concentration nitrocellulose to the cotton feed tank for the next batch of nitrocellulose production, where it is processed into high-quality nitrocellulose.

6. The system according to claim 5, characterized in that, The high-efficiency thickening filter also includes a cleaning pump, which is used to quickly flush the inside of the high-efficiency thickening filter.

7. The system according to claim 5, characterized in that, The high-efficiency concentration filter also includes a siphon tank, which is connected to the precision filter via a one-way valve and a pipeline. The fourth suction pump draws the neutral water containing suspended fibers into the siphon tank. When the liquid level in the siphon tank reaches a certain height, the one-way valve automatically opens to deliver the neutral water containing suspended fibers to the precision filter.

8. The system according to claim 5, characterized in that, The high-efficiency concentrator also includes an ultrasonic cleaning device. When the operating frequency of the fifth suction pump increases to a set value, the ultrasonic cleaning device is activated to clean the filter holes of the fan-shaped ceramic filter plate.

9. The system according to claim 1, characterized in that, It also includes a PLC control system, which is electrically connected to the electrical components that need to be controlled in the online cotton material recycling and neutral water regeneration system of the nitrocellulose production process.

10. An online cotton material recycling and neutral water regeneration process in the production of nitrocellulose, applied to the system according to any one of claims 1 to 9, characterized in that, Includes the following steps: The neutral water containing cotton material generated from the nitrocellulose production line is introduced into the vertical flow sedimentation and recovery tower for sedimentation treatment, and the neutral water containing suspended fibers and the high-concentration nitrocellulose are separated. The high-concentration nitrocellulose is returned to the production of the current batch of nitrocellulose and processed into high-quality nitrocellulose. The neutral water containing suspended fibers is introduced into the precision filter for filtration to obtain the high-quality neutral water and the suspended fibers. The high-quality neutral water is reused in the nitrocellulose production process; The suspended fibers obtained from the precision filter are introduced into the high-efficiency thickener filter for concentration and dehydration. The cotton concentration is monitored in real time. When the concentration reaches or exceeds a set value, the concentrated low-concentration nitrocellulose is returned to the cotton feed tank for the next batch of nitrocellulose production and processed into high-quality nitrocellulose.

Images