Papermaking wastewater treatment device capable of improving paper pulp recovery rate

Abstract

The papermaking wastewater treatment device comprises a barrel, a supporting seat is mounted at the lower end of the barrel, a plurality of annular electric heating plates are connected to the inner wall of the barrel, and a feeding opening is formed in the upper end of the barrel; the stirring mechanism comprises a rotating pipe rotationally connected to the inner bottom of the barrel body, the outer side of the rotating pipe is fixedly connected with a plurality of stirring shafts, the lower end of the rotating pipe extends to the outside, the right side of the barrel body is fixedly connected with a high-pressure box body, and a double-shaft motor is installed on the right side of the high-pressure box body; synchronous wheels are mounted on an output shaft at the lower end of the double-shaft motor and the outer side of the rotating pipe, and the two synchronous wheels are in transmission connection through a synchronous belt; and the gas supply mechanism is used for increasing the oxygen content of the wastewater. In the use process of the wastewater treatment device, a water body containing a dispersing agent is degraded and the dispersing agent is removed in a biodegradation manner, so that the recovery rate of paper pulp is increased.

Description

Technical Field

[0001] The invention relates to the field of pulp wastewater treatment, and in particular to a papermaking wastewater treatment device for improving pulp recovery rate. Background Art

[0002] my country's papermaking industry mainly uses straw and wood pulp as raw materials, and the production process usually includes pulping, washing, bleaching and papermaking. The composition of wastewater generated in the papermaking process varies greatly depending on the pulping methods (such as alkaline pulping, chemical mechanical pulping and mechanical pulping), raw material types, pulping yields, and whether there is chemical recovery. However, it generally contains a large amount of suspended solids, high concentrations of biochemical oxygen demand (BOD), chemical oxygen demand (COD) and some toxic substances. Therefore, the treatment of papermaking wastewater mostly adopts a combination of physical, chemical and biological treatment methods to ensure the effective removal of pollutants; In the prior art, in order to aid retention and filtration, prevent sedimentation and optimize paper performance during the pulp production process, an additive called "papermaking dispersant", such as polyacrylamide, is usually added to the pulp to increase the viscosity of the pulp, promote the uniform distribution of fibers and fillers, thereby ensuring the quality and smoothness of the paper, and improving the stability of the production process, reducing paper breakage and powdering problems, while enhancing the dry and wet strength of the paper and saving raw materials. When these dispersants subsequently enter the wastewater system, the suspended matter in the wastewater will be difficult to settle, resulting in fiber dispersion, which is difficult to collect and treat, affecting the recovery rate of the pulp. Therefore, it is necessary to consider how to solve this problem. Summary of the invention

[0003] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a papermaking wastewater treatment device for improving the pulp recovery rate. During use, the wastewater treatment device utilizes biodegradation to degrade water containing dispersants and remove the dispersants, thereby improving the pulp recovery rate.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: A papermaking wastewater treatment device for improving pulp recovery rate comprises a cylinder, a support seat is installed at the lower end of the cylinder, a plurality of annular electric heating plates are connected to the inner wall of the cylinder, and a feeding port is installed at the upper end of the cylinder; a stirring mechanism, the stirring mechanism comprises a rotating tube rotatably connected to the bottom of the cylinder, a plurality of stirring shafts are fixedly connected to the outer side of the rotating tube, the lower end of the rotating tube extends to the outside, a high-pressure box is fixedly connected to the right side of the cylinder, a double-axis motor is installed on the right side of the high-pressure box, synchronous wheels are installed on the lower output shaft of the double-axis motor and the outer side of the rotating tube, and the two synchronous wheels are connected by synchronous belt transmission; a gas supply mechanism, the gas supply mechanism is used to increase the oxygen content of the wastewater and promote biodegradation; a pressure regulating mechanism, the pressure regulating mechanism cooperates with the gas supply mechanism.

[0005] Preferably, the gas supply mechanism includes an L-shaped plate fixedly connected to the right side of the high-pressure box body, a piston cylinder is installed on the left side of the vertical part of the L-shaped plate, a first piston block that can slide left and right is arranged in the piston cylinder, the upper output shaft of the dual-axis motor is fixedly connected to a rotating plate, the rotating plate is disc-shaped, and a connecting rod is rotatably connected to the eccentric part of the upper end of the rotating plate, and the left end of the connecting rod is rotatably connected to the left end of the first piston block.

[0006] Preferably, the right side space of the piston cylinder is connected to the outside through a one-way port, and the right side space of the piston cylinder is connected to the inside of the high-pressure box through a one-way pipe.

[0007] Preferably, a one-way valve is installed inside the one-way port and the one-way tube. The one-way valve in the one-way port flows from the outside to the right side space of the piston cylinder, and the one-way valve inside the one-way tube flows from the right side space of the piston cylinder to the inside of the high-pressure box.

[0008] Preferably, the inner bottom of the high-pressure box is connected to a vortex tube, a pressure relief valve is installed in the air inlet end of the vortex tube, the hot air end of the vortex tube is connected to a hot air duct, the rotating tube is a tube body with a sealed upper end and a conductive lower end, and the lower end of the rotating tube is connected to the air outlet end of the hot air duct through a rotating joint.

[0009] Preferably, the rotating tube is located inside the cylinder and is fixedly connected to a plurality of stirring tubes on the outside thereof, the plurality of stirring tubes are connected to the rotating tube, a plurality of air holes are provided at the lower ends of the plurality of stirring tubes, the ends of the plurality of stirring tubes away from the rotating tube are sealed, the upper end of each stirring tube is fixedly connected to a stirring plate, and each stirring plate is provided with a plurality of curved channels.

[0010] Preferably, the pressure regulating mechanism includes a pressure regulating cylinder fixedly connected to the upper end of the cylinder body, a piston groove is opened at the lower end of the pressure regulating cylinder, the lower end of the piston groove extends into the interior of the cylinder body, the inner top of the piston groove is connected to the outside through a through opening, a second piston block that can slide up and down is arranged in the piston groove, and the upper end of the second piston block is elastically connected to the inner top of the piston groove through a spring.

[0011] Preferably, a mounting block is fixedly connected to the inner top of the piston groove, a touch delay switch is installed at the lower end of the mounting block, the inner top of the cylinder is connected to an air vent pipe, an electromagnetic valve is installed inside the air vent pipe, and the electromagnetic valve is electrically connected to the touch delay switch.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The wastewater is heated to the optimal activity temperature of thermophilic Bacillus by the annular electric heating plate. With the use of the stirring structure, the internal temperature uniformity and microbial concentration uniformity are stronger, which effectively improves the degradation ability of microorganisms and ensures that the biochemical reaction in the wastewater treatment process is in the optimal state.

[0013] 2. Oxygen supply is achieved through intermittent injection of high-pressure gas, which meets the oxygen demand of thermophilic Bacillus. At the same time, the principle of releasing hot air at the hot end of the vortex tube is utilized, and the wastewater temperature will not be lowered due to heat exchange, ensuring that the water temperature is always within an appropriate range.

[0014] 3. By using the pressure regulating mechanism, the air pressure inside the cylinder can be increased and decreased repeatedly. Under high pressure, the bubbles floating in the water are smaller. When the pressure suddenly turns into low pressure, the floating bubbles will expand and burst rapidly, so that the oxygen in the bubbles can be dissolved in the water to a higher degree.

[0015] 4. The inside of the cylinder is always at a higher pressure than normal. Under high pressure, it is more conducive to the dissolution of oxygen in the water, promoting the process of dissolved oxygen, and ensuring the oxygen demand of thermophilic stearic bacillus. In addition, under high pressure, the actual size of the bubbles is smaller than the normal pressure. According to Stokes' law, the smaller the bubbles, the smaller their floating speed, the longer they stay in the water, and the possibility of bursting in the water increases, thereby increasing the dissolved oxygen rate.

[0016] 5. During the rotation of the rotating tube, the stirring tube and the stirring plate will both rotate. The rotation of the stirring tube will allow the bubbles discharged from the pores to cover the wastewater more evenly, while the rotation of the stirring plate will allow a portion of the floating bubbles to pass through the curved channel. After the wastewater passes through the curved channel, the bubbles will tilt downward. In this way, the overall path of some bubbles floating up can be changed, so that they can stay in the water longer. In addition, due to the inclined water flow, the bubbles will also be deformed in the inclined direction, making their upward resistance greater and staying in the water longer.

[0017] In summary, the wastewater treatment device uses biological treatment to completely remove the dispersant in the wastewater, ensuring the pulp recovery rate. During the biological treatment process, the biological bacteria are placed in a more suitable environment, ensuring the efficiency of the biological treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of a papermaking wastewater treatment device for improving pulp recovery rate proposed by the present invention; Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of; Figure 3 for Figure 2 A schematic diagram of the front structure of Figure 4 It is a structural schematic diagram of the gas supply mechanism; Figure 5 It is a cross-sectional view of the cooperation between the dual-axis motor and the piston cylinder; Figure 6 A cross-sectional view of the connection between one of the stirring tubes and the rotating plate; Figure 7 for Figure 6 The left side structural diagram of .

[0019] In the figure: 1 cylinder, 2 support seat, 3 feeding port, 4 pressure regulating cylinder, 5 port, 6 vent pipe, 7 solenoid valve, 8 high pressure box, 9 double shaft motor, 10 L-shaped plate, 11 one-way pipe, 12 hot air pipe, 13 annular electric heating plate, 14 spring, 15 second piston block, 16 rotating pipe, 17 stirring shaft, 18 stirring pipe, 19 rotary joint, 20 synchronous wheel, 21 synchronous belt, 22 mounting block, 23 touch delay switch, 24 rotating plate, 25 piston cylinder, 26 first piston block, 27 connecting rod, 28 one-way port, 29 stirring plate, 30 curved channel, 31 air hole, 32 vortex tube, 33 pressure relief valve, 34 piston groove. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0021] Reference Figure 1-Figure 7 , a papermaking wastewater treatment device for improving pulp recovery rate, comprising a cylinder 1, a support seat 2 is installed at the lower end of the cylinder 1, a plurality of annular electric heating plates 13 are connected to the inner wall of the cylinder 1, and the wastewater inside the cylinder 1 can be heated by the annular electric heating plates 13 to facilitate biodegradation, a feeding port 3 is installed at the upper end of the cylinder 1, and the feeding port 3 adopts a sealable structure, which is also installed as a sealing cover shown in the figure. It should be noted that a pump body structure not shown in the figure is also installed to pump out the treated wastewater; As an embodiment of the present invention, it also includes a stirring mechanism, which includes a rotating tube 16 rotatably connected to the bottom of the cylinder 1, a plurality of stirring shafts 17 are fixedly connected to the outer side of the rotating tube 16, and the lower end of the rotating tube 16 extends to the outside. A high-pressure box 8 is fixedly connected to the right side of the cylinder 1, and the high-pressure box 8 is filled with high-pressure gas. A double-axis motor 9 is installed on the right side of the high-pressure box 8. The lower end output shaft of the double-axis motor 9 and the outer side of the rotating tube 16 are both installed with synchronous wheels 20, and the two synchronous wheels 20 are connected through a synchronous belt 21. As an embodiment of the present invention, it also includes a gas supply mechanism, which is used to increase the oxygen content of the wastewater and promote biodegradation. The gas supply mechanism includes an L-shaped plate 10 fixedly connected to the right side of the high-pressure box 8, a piston cylinder 25 is installed on the left side of the vertical portion of the L-shaped plate 10, and a first piston block 26 that can slide left and right is arranged in the piston cylinder 25. The upper end output shaft of the dual-axis motor 9 is fixedly connected to a rotating plate 24, and the rotating plate 24 is disc-shaped. The upper end eccentric part of the rotating plate 24 is rotatably connected to a connecting rod 27, and the left end of the connecting rod 27 is connected to the first piston block 26. The left end is rotatably connected, and the right side space of the piston cylinder 25 is connected to the outside world through the one-way port 28, and the right side space of the piston cylinder 25 is connected to the inside of the high-pressure box 8 through the one-way pipe 11. One-way valves are installed inside the one-way port 28 and the one-way pipe 11. The one-way valve in the one-way port 28 flows in a one-way direction from the outside to the right side space of the piston cylinder 25. Furthermore, an air filter can be installed at the air intake part of the one-way port 28 to separate and remove impurities and dust in the air. The one-way valve inside the one-way pipe 11 flows in a one-way direction from the right side space of the piston cylinder 25 to the inside of the high-pressure box 8; As an embodiment of the present invention, the inner bottom of the high-pressure box 8 is connected with a vortex tube 32. The vortex tube 32 is a prior art. After the high-pressure gas is introduced, a low-temperature airflow is generated at the cold end and a high-temperature airflow is generated at the hot end. A pressure relief valve 33 is installed in the air inlet end of the vortex tube 32. The hot air end of the vortex tube 32 is connected with the hot air pipe 12. The rotating tube 16 is a tube body with a sealed upper end and a conductive lower end. The lower end of the rotating tube 16 is connected to the air outlet end of the hot air pipe 12 through a rotating joint 19. The rotating tube 16 is located on the outer side of the cylinder 1 and is fixedly connected with a plurality of stirring tubes 18. The plurality of stirring tubes 18 are all connected with the rotating tube 16. The lower ends of the plurality of stirring tubes 18 are all provided with a plurality of air holes 31. The ends of the plurality of stirring tubes 18 away from the rotating tube 16 are all sealed. The upper end of each stirring tube 18 is fixedly connected with a stirring plate 29. Each stirring plate 29 is provided with a plurality of curved channels 30. By adopting this method, the speed of air floating can be effectively reduced. As an embodiment of the present invention, it also includes a pressure regulating mechanism, which cooperates with the gas supply mechanism. The pressure regulating mechanism includes a pressure regulating cylinder 4 fixedly connected to the upper end of the cylinder 1, and a piston groove 34 is opened at the lower end of the pressure regulating cylinder 4. The lower end of the piston groove 34 extends to the inside of the cylinder 1, and the inner top of the piston groove 34 is connected to the outside through the opening 5. A second piston block 15 that can slide up and down is arranged in the piston groove 34, and the upper end of the second piston block 15 is elastically connected to the inner top of the piston groove 34 through a spring 14. The inner top of the piston groove 34 is fixedly connected with a mounting block 22, and a touch delay switch 23 is installed at the lower end of the mounting block 22. The inner top of the cylinder 1 is connected with an air venting pipe 6, and an electromagnetic valve 7 is installed inside the air venting pipe 6. The electromagnetic valve 7 is electrically connected to the touch delay switch 23. When the touch delay switch 23 is triggered, the electromagnetic valve 7 will be powered on for 3 seconds and then automatically powered off.

[0022] In the present invention, when used specifically, wastewater is fed through the feeding port 3, and then an appropriate amount of thermophilic Bacillus is fed into the wastewater, and then the feeding port 3 is sealed, and then the annular electric heating plate 13 is started, and the annular electric heating plate 13 can heat the wastewater to about 60° C., so that the activity of thermophilic Bacillus is in the best state; At the same time, the dual-axis motor 9 is started. The start of the dual-axis motor 9 will drive the rotating tube 16 through the transmission effect of the synchronous belt 21 and the synchronous wheel 20. The rotation of the rotating tube 16 will rotate the multiple stirring shafts 17, so that the water body is stirred, the thermophilic Bacillus stearothermophilus inside is dispersed more evenly, and the temperature of the water body is more uniform; In the above process, the start-up of the dual-axis motor 9 will also drive the rotating plate 24 to rotate. The rotation of the rotating plate 24 will allow the first piston block 26 to reciprocate left and right through the connecting rod 27. The reciprocating movement of the first piston block 26 will generate a one-way gas flow between the outside, the piston cylinder 25 and the high-pressure box 8 through the one-way port 28 and the one-way valve inside the one-way tube 11. The one-way gas flow can inject high-pressure gas into the high-pressure box 8. Since there is high-pressure gas in the high-pressure box 8 and its air pressure is near the threshold range of the pressure relief valve 33, when the gas is injected again, the air pressure will be higher than the threshold of the pressure relief valve 33, so that part of the high-pressure gas will be released. When the gas is released to a level lower than the threshold of the pressure relief valve 33, The pressure relief valve 33 is closed again, so that the pressure relief valve 33 will intermittently release high-pressure gas. After the released high-pressure gas passes through the vortex tube 32, it is discharged from the hot end and the cold end. The high-pressure gas discharged from the hot end will enter the rotating tube 16 through the hot air pipe 12, and finally be discharged from the multiple air holes 31 of the stirring tube 18. After the discharged high-temperature gas enters the wastewater, the floating bubbles burst in the water to increase the dissolved oxygen content of the water body, thereby ensuring that the thermophilic Bacillus is in an efficient degradation state, and the bubbles above can further promote the flow of the water body, making the overall temperature and the distribution of thermophilic Bacillus more uniform, and because the gas itself is in a high-temperature state, it will not exchange heat to reduce the wastewater temperature, ensuring that the water temperature is always in a suitable state; It should be noted that as the gas is continuously injected into the cylinder 1, the air pressure in the top space of the cylinder 1 increases, and at the same time, the second piston block 15 is pushed upward and the spring 14 is compressed. When the second piston block 15 moves upward to contact the touch delay switch 23, the solenoid valve 7 is energized for 3 seconds, so that the high pressure inside the cylinder 1 will be quickly released through the vent pipe 6. Under the elastic action of the spring 14, the second piston block 15 moves downward. When the solenoid valve 7 is closed, the air pressure inside the cylinder 1 will continue to increase, and the above process will be repeated. In the specific use process, using this method, the air pressure inside the cylinder 1 will increase and decrease reciprocally. Under high pressure, the bubbles floating in the water are small, and when it suddenly becomes low pressure, the floating bubbles will expand and burst rapidly, so that the oxygen in the bubbles can be dissolved in the water to a higher degree. During this process, the inside of the cylinder 1 is always at a higher pressure than normal. Under high pressure, it is more conducive to the dissolution of oxygen in the water body, promoting the dissolution of oxygen, and ensuring the demand of Bacillus stearothermophilus for oxygen. In addition, under high pressure, the actual size of the bubbles is smaller than the normal pressure. According to Stokes' law, the smaller the bubbles are, the smaller their floating speed is, the longer they stay in the water body, and the possibility of bursting in the water body increases, thereby increasing the dissolved oxygen rate. In addition, it should be noted that during the rotation of the rotating tube 16, the stirring tube 18 and the stirring plate 29 will both rotate. The rotation of the stirring tube 18 will allow the bubbles discharged from the pores 31 to cover the wastewater more evenly, while the rotation of the stirring plate 29 will allow a portion of the floating bubbles to pass through the curved channel 30. After the wastewater passes through the curved channel 30, the bubbles will move downwardly with an inclination. In this way, the overall path of the floating of some bubbles can be changed, so that they can stay in the water body for a longer time. In addition, due to the inclined water flow, the bubbles will also be deformed in the inclined direction, so that the upward movement resistance is greater and the bubbles stay in the water body for a longer time. Through the above structure, the effect of biological treatment can be guaranteed, so that the dispersant is completely removed, thereby improving the subsequent pulp recovery rate.

[0023] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A papermaking wastewater treatment device for improving pulp recovery rate, characterized in that: include: A cylinder (1), a support seat (2) being installed at the lower end of the cylinder (1), a plurality of annular electric heating plates (13) being connected to the inner wall of the cylinder (1), and a feeding port (3) being installed at the upper end of the cylinder (1); A stirring mechanism, the stirring mechanism comprising a rotating tube (16) rotatably connected to the bottom of the cylinder (1), a plurality of stirring shafts (17) being fixedly connected to the outer side of the rotating tube (16), the lower end of the rotating tube (16) extending to the outside, a high-voltage box (8) being fixedly connected to the right side of the cylinder (1), a double-shaft motor (9) being installed on the right side of the high-voltage box (8), a synchronous wheel (20) being installed on the lower output shaft of the double-shaft motor (9) and the outer side of the rotating tube (16), and the two synchronous wheels (20) being connected by a synchronous belt (21); A gas supply mechanism, which is used to increase the oxygen content of the wastewater and promote biodegradation; A pressure regulating mechanism cooperates with the gas supply mechanism.

2. A papermaking wastewater treatment device for improving pulp recovery rate according to claim 1, characterized in that: The gas supply mechanism comprises an L-shaped plate (10) fixedly connected to the right side of the high-pressure box (8), a piston cylinder (25) is installed on the left side of the vertical portion of the L-shaped plate (10), a first piston block (26) that can slide leftward and rightward is arranged in the piston cylinder (25), the upper end output shaft of the dual-axis motor (9) is fixedly connected to a rotating plate (24), the rotating plate (24) is in the shape of a disc, and a connecting rod (27) is rotatably connected to the eccentric portion of the upper end of the rotating plate (24), and the left end of the connecting rod (27) is rotatably connected to the left end of the first piston block (26).

3. A papermaking wastewater treatment device for improving pulp recovery rate according to claim 2, characterized in that: The right side space of the piston cylinder (25) is connected to the outside through a one-way port (28), and the right side space of the piston cylinder (25) is connected to the inside of the high-pressure box (8) through a one-way pipe (11).

4. A papermaking wastewater treatment device for improving pulp recovery rate according to claim 3, characterized in that: One-way valves are installed inside the one-way port (28) and the one-way tube (11). The one-way valve inside the one-way port (28) allows flow from the outside to one-way into the space on the right side of the piston cylinder (25). The one-way valve inside the one-way tube (11) allows flow from the space on the right side of the piston cylinder (25) to one-way into the high-pressure box (8).

5. The papermaking wastewater treatment device for improving pulp recovery rate according to claim 3, characterized in that: The inner bottom of the high-pressure box (8) is connected to a vortex tube (32), a pressure relief valve (33) is installed in the air inlet end of the vortex tube (32), the hot air end of the vortex tube (32) is connected to the hot air pipe (12), the rotating tube (16) is a tube body with a sealed upper end and a conductive lower end, and the lower end of the rotating tube (16) is connected to the air outlet end of the hot air pipe (12) via a rotating joint (19).

6. A papermaking wastewater treatment device for improving pulp recovery rate according to claim 5, characterized in that: The rotating tube (16) is located inside the cylinder (1) and is fixedly connected to a plurality of stirring tubes (18) on its outer side. The plurality of stirring tubes (18) are in communication with the rotating tube (16). The lower ends of the plurality of stirring tubes (18) are provided with a plurality of air holes (31). The ends of the plurality of stirring tubes (18) away from the rotating tube (16) are sealed. The upper end of each stirring tube (18) is fixedly connected to a stirring plate (29), and each stirring plate (29) is provided with a plurality of curved channels (30).

7. The papermaking wastewater treatment device for improving pulp recovery rate according to claim 1, characterized in that: The pressure regulating mechanism comprises a pressure regulating cylinder (4) fixedly connected to the upper end of the cylinder (1); a piston groove (34) is provided at the lower end of the pressure regulating cylinder (4); the lower end of the piston groove (34) extends into the interior of the cylinder (1); the inner top of the piston groove (34) is connected to the outside through a through opening (5); a second piston block (15) which can slide up and down is provided in the piston groove (34); the upper end of the second piston block (15) is elastically connected to the inner top of the piston groove (34) through a spring (14).

8. The papermaking wastewater treatment device for improving pulp recovery rate according to claim 7, characterized in that: The inner top of the piston groove (34) is fixedly connected to a mounting block (22), the lower end of the mounting block (22) is mounted with a touch delay switch (23), the inner top of the cylinder (1) is connected to an air release pipe (6), the interior of the air release pipe (6) is mounted with an electromagnetic valve (7), and the electromagnetic valve (7) is electrically connected to the touch delay switch (23).

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