Liquid adding and stirring equipment and softening and direct filtering system

Abstract

The invention relates to the technical field of wastewater treatment, and particularly discloses liquid adding and stirring equipment and a softening and direct filtering system. The liquid adding and stirring equipment comprises a liquid adding annular pipe, a shaft pipe, a rotator and a plurality of paddle units. The rotator is connected with the shaft tube. And the liquid adding ring pipe is sleeved outside the shaft pipe. And when the rotator drives the shaft tube to rotate, the liquid adding ring tube is kept in a seamless communication state with the shaft tube. And each paddle unit is connected to the shaft tube. Each paddle unit comprises a frame pipe and a plurality of rotating pipes. And the other end of the frame tube is connected with the shaft tube. The frame tube is provided with a plurality of combinations of opposite notches and grooves. A shaft tube opens into each notch. And one end of each rotating pipe is always communicated with the notch, and the other end is inserted into the groove. The rotating pipe is provided with a plurality of liquid outlets. The rotating pipe rotates along with the turnover of the frame pipe, the liquid medicine can be efficiently dispersed in wastewater, the hardness removal reaction efficiency is improved, and the paddle unit is small in resistance, low in energy consumption and long in service life when rotating in water.

Description

Technical Field

[0001] The present application relates to the technical field of wastewater treatment, and particularly relates to a liquid adding and stirring device and a softening direct filtration system. Background Art

[0002] At present, the treatment of high-hardness and high-turbidity wastewater has become an important topic in environmental protection. The treatment steps usually include multiple steps such as floating removal, hardness removal, preliminary filtration, flocculation, high-efficiency precipitation, air flotation, deep filtration, disinfection, reverse osmosis, and acid-base neutralization.

[0003] For hardness removal, the chemical softening method is adopted. According to the water quality, chemicals such as lime, soda ash, and caustic soda are added to react with calcium ions and magnesium ions in the water to form insoluble compounds CaCO3 and Mg(OH)2, thereby reducing the water hardness. In order to improve the efficiency of the hardness removal reaction, it is necessary to efficiently disperse the added chemicals in the wastewater. Currently, the method of dropping chemicals at fixed points is generally used, and during the dropping process, a solid plate-shaped stirring paddle is also used to stir the water to disperse the chemicals. The hardness removal reaction tank is generally large. If the stirring paddle is designed to be correspondingly large, the stirring resistance is large, the energy consumption is high, and the service life of the stirring paddle is short. Therefore, currently, the stirring paddle is generally designed to be small. It takes a long time for a small solid plate-shaped stirring paddle to evenly disperse the chemicals in the reaction tank, which reduces the efficiency of the hardness removal reaction. Summary of the Invention

[0004] Based on the problem that it takes a long time for a small solid plate-shaped stirring paddle to evenly disperse the chemicals in the reaction tank, which reduces the efficiency of the hardness removal reaction, the present application proposes a liquid adding and stirring device for improving the efficiency of chemical dispersion in water, and also proposes a softening direct filtration system including the liquid adding and stirring device. The specific solutions are as follows.

[0005] In the first aspect, the present application proposes a liquid adding and stirring device and adopts the following technical solutions.

[0006] A liquid adding and stirring device includes a liquid adding ring pipe, a shaft pipe, a rotator, and a plurality of paddle units; the rotator is connected to the shaft pipe; the liquid adding ring pipe is sleeved outside the shaft pipe; in the state where the rotator drives the shaft pipe to rotate, the liquid adding ring pipe remains in a seamless communication state with the shaft pipe; each paddle unit is connected to the shaft pipe. Each paddle unit includes a frame pipe and a plurality of rotating pipes; one end of the frame pipe communicates with the shaft pipe, and the other end is connected to the shaft pipe; the frame pipe has a combination of a plurality of relative notches and grooves; the shaft pipe leads to each notch; one end of each rotating pipe always communicates with the notch, and the other end is inserted into the groove; the rotating pipe has a plurality of liquid outlets.

[0007] By adopting the above technical solution, several rotating tubes installed on the frame tube serve as liquid outlets and rotate automatically as the frame tube rotates, which can efficiently disperse the liquid medicine in the wastewater, improve the hardening removal reaction efficiency, and the paddle unit has less resistance when rotating in water, low energy consumption and long service life.

[0008] A preferred solution of the liquid adding and stirring device is that the rotating tube includes an intermediate tube and three identical horizontal arc tubes. The inner ends of the three horizontal arc tubes are communicated with the intermediate tube; the concave surface of each horizontal arc tube faces the convex surface of the adjacent horizontal arc tube; the outer end of the horizontal arc tube is the liquid outlet. The upper end of the intermediate tube is inserted into the notch and communicated with the notch, and the lower end of the intermediate tube is inserted into the groove; the lower end of the intermediate tube is not communicated with the shaft tube.

[0009] By adopting the above technical solution, the three horizontal arc tubes complement each other during rotation and jointly drive the rotating tube to rotate automatically, so as to evenly disperse the discharged liquid medicine in water.

[0010] A preferred solution of the liquid adding and stirring device is that the paddle unit further includes a buoyancy valve; the buoyancy valve includes a counterweight, a float, a conduit and a box. The frame tube includes an upper horizontal tube, a vertical tube and a lower horizontal tube connected in sequence; the upper horizontal tube is communicated with the shaft tube, and the lower horizontal tube is not communicated with the shaft tube; the upper horizontal tube is provided with the notch; the lower horizontal tube is provided with the groove. The box is fixed on the shaft tube; the upper end of the conduit is communicated with the box, and the lower end is communicated with the upper surface of the upper horizontal tube; the float is installed in the box; the counterweight is installed in the frame tube and the conduit; the float is connected to the counterweight; the box has several water filling holes; when the box is not filled with water, the counterweight cuts off the frame tube; when the box is full of water, the float floats to the top of the box, the counterweight releases the cutting off of the frame tube, and at least a part of the counterweight is located in the conduit.

[0011] By adopting the above technical solution, when the buoyancy valve is immersed in water, the channel of the frame tube is opened, and the liquid medicine can be discharged from the liquid outlet. At this time, the frame tube is also immersed in water, which can play the role of stirring and injecting the liquid medicine into the water at the same time. The buoyancy valve that is not immersed in water cuts off the channel of the corresponding frame tube, avoiding the liquid medicine sprayed from the frame tube above water onto the frame tube, outside the reaction tank or the reaction tank wall and drying, which may block the liquid outlet and is not conducive to cleaning.

[0012] A preferred solution of the liquid adding and stirring device is that the lower surface of the frame tube has a downward convex part; when the box is not filled with water, the lower end of the counterweight is embedded in the convex part, and the upper end is located in the conduit.

[0013] By adopting the above technical solution, the liquid medicine is not likely to penetrate through the lower surface of the counterweight and enter the rotating tube.

[0014] A preferred solution of the liquid adding and stirring device is that the counterweight is square; the main cross-section of the frame tube is square; the conduit is square; the counterweight slidably fits in the frame tube and the conduit.

[0015] By adopting the above technical solution, the counterweight has a good effect of truncating the frame tube, and the counterweight can slidably fit between the conduit and the frame tube.

[0016] A preferred solution of the liquid adding and stirring device is that on the periphery of the liquid adding and stirring device, three of the paddle units are arranged in each circle, the adjacent paddle units are spaced 120°, and the three paddle units are arranged from high to low along a rotating direction.

[0017] By adopting the above technical solution, the liquid medicine is dispersed at multiple height positions in the water, improving the dispersion uniformity, and can improve the hardening removal reaction efficiency when removing hardness from wastewater.

[0018] A preferred solution of the liquid adding and stirring device is that the liquid adding and stirring device includes an upper limit plate and a lower limit plate; the upper limit plate is fixed at the upper end of the shaft tube; the lower limit plate is fixedly surrounded on the periphery of the shaft tube; the rotator is connected to the upper limit plate; the liquid adding ring tube abuts between the upper limit plate and the lower limit plate; the inner ring surface of the liquid adding ring tube has an annular hole; the periphery of the shaft tube has a plurality of water through holes; the annular hole is aligned with the plurality of water through holes; upper and lower sealing rings are arranged between the liquid adding ring tube and the shaft tube, respectively located on the upper and lower sides of the annular hole.

[0019] By adopting the above technical solution, the rotator can drive the shaft tube and the paddle unit to rotate freely, and maintain sealed communication with the liquid adding ring tube during rotation, so as to continuously discharge the liquid medicine from the liquid outlet for reaction during rotation.

[0020] A preferred solution of the liquid adding and stirring device is that the liquid adding and stirring device further includes a bracket and a plurality of liquid adding mechanisms; the rotator is fixed on the bracket; each liquid adding mechanism includes a liquid medicine tank, a liquid adding pipe, a liquid adding pump and a one-way valve; the liquid medicine tank is fixed on the bracket; one end of the liquid adding pipe communicates with the liquid medicine tank, and the other end communicates with the liquid adding ring tube; the liquid adding pump and the one-way valve are both installed on the liquid adding pipe.

[0021] By adopting the above technical solution, each liquid medicine tank can hold one kind of liquid medicine, and can inject one kind of liquid medicine into the paddle unit in sequence for reaction.

[0022] In a second aspect, the present application also proposes a softening direct filtration system and adopts the following technical solutions.

[0023] A softening direct filtration system includes the above-mentioned liquid adding and stirring equipment, and also includes a wastewater pipe, a pre-sedimentation and regulation tank, a front pipeline, a front pump, a reaction tank, a rear pipeline, a pressure pump, and a direct filtration device; the wastewater pipe leads to the pre-sedimentation and regulation tank; the pre-sedimentation and regulation tank leads to the reaction tank through the front pipeline; the front pump is installed on the front pipeline; the reaction tank leads to the direct filtration device through the rear pipeline; the pressure pump is installed on the rear pipeline; the shaft pipe and multiple paddle units of the liquid adding and stirring equipment extend into the reaction tank.

[0024] By adopting the above technical solutions, the wastewater first enters the pre-sedimentation and regulation tank for static sedimentation, and then the supernatant is input into the reaction tank for hardening removal reaction to generate precipitation. After the reaction, it is directly filtered through the direct filtration device and then can be discharged from the system.

[0025] In summary, the liquid adding and stirring equipment and the softening direct filtration system of the present application have the following beneficial effects: The liquid adding and stirring equipment uses a hollow frame pipe as the main body of the stirring paddle, with small rotation resistance and low energy consumption in water. A rotating pipe is installed on the frame pipe as the liquid outlet, and the liquid medicine is discharged into the water during the rotation of the rotating pipe. The liquid medicine is fully stirred and dispersed, with high dispersion efficiency. Applying this liquid adding and stirring equipment to the hardening removal treatment of high-hardness wastewater can achieve a high hardening removal reaction efficiency and improve the treatment speed.

[0026] Applying this softening direct filtration system to the treatment of high-turbidity and high-hardness wastewater, the wastewater first undergoes static precipitation in the pre-sedimentation and regulation tank to precipitate most of the sediment, then undergoes hardening removal treatment, and after hardening removal, it is filtered by the direct filtration device. Then, the turbidity substances, calcium ions, magnesium ions, etc. in the wastewater are all treated and can be discharged from the system. Description of the Drawings

[0027] Figure 1 It is a structural diagram of an embodiment of the liquid adding and stirring equipment.

[0028] Figure 2 It is Figure 1 a cross-sectional view of

[0029] Figure 3 It is Figure 2 an enlarged view of area A of

[0030] Figure 4 It is Figure 2 an enlarged view of area B of

[0031] Figure 5 It is Figure 2 an enlarged view of area C of

[0032] Figure 6It is a structural diagram of an implementation of a softening direct filtration system.

[0033] Reference numerals: 1, support; 2, rotator; 3, upper limit plate; 4, shaft tube; 5, lower limit plate; 6, liquid addition ring tube; 7, paddle unit; 8, liquid addition mechanism; 81, liquid medicine tank; 82, liquid addition pipe; 83, liquid addition pump; 84, one-way valve; 601, annular hole; 401, water passing hole; 9, upper sealing ring; 10, lower sealing ring; 71, buoyancy valve; 72, frame tube; 73, rotating tube; 721, upper horizontal tube; 722, vertical tube; 723, lower horizontal tube; 7211, notch; 7231, groove; 731, intermediate tube; 732, horizontal arc tube; 7321, liquid outlet; 711, counterweight; 712, float; 713, conduit; 714, box; 7141, water filling hole; 7212, lower convex part; 11, waste water pipe; 12, pre-sedimentation adjustment tank; 13, front pipeline; 14, front pump; 15, reaction tank; 16, rear pipeline; 17, pressure pump; 18, direct filtration equipment. Specific implementation manners

[0034] Next, the technical solutions in the embodiments will be described clearly and completely with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the following embodiments, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application. Embodiment 1

[0035] Refer to Figure 1 , a liquid addition and stirring device, including a support 1, a rotator 2, an upper limit plate 3, a shaft tube 4, a lower limit plate 5, a liquid addition ring tube 6, a plurality of paddle units 7, and a plurality of liquid addition mechanisms 8.

[0036] Each liquid addition mechanism 8 includes a liquid medicine tank 81, a liquid addition pipe 82, a liquid addition pump 83, and a one-way valve 84. An electromagnetic valve or the like can also be installed on the liquid addition pipe 82 to automatically control the on-off of the pipeline. Each liquid medicine tank 81 can hold a kind of liquid medicine, such as lime, soda ash, caustic soda and other agents, so as to react with calcium ions and magnesium ions in water to generate insoluble compounds CaCO3 and Mg(OH)2, reducing the water hardness. One end of the liquid addition pipe 82 communicates with the conical bottom of the liquid medicine tank 81, and the other end communicates with the liquid addition ring tube 6. The liquid addition pump 83 and the one-way valve 84 are both installed on the liquid addition pipe 82, and are respectively used for pumping the liquid medicine and preventing the liquid medicine from flowing back. Among them, the liquid medicine tank 81 is installed on the support 1.

[0037] As Figure 2, the spinner 2 can be a motor. The stator of the motor is fixed on the bracket 1, and its rotor, i.e., the rotating shaft, is fixedly connected to the upper limit plate 3 downward. The upper limit plate 3 is fixedly connected to the top end of the shaft tube 4 downward. The lower limit plate 5 is fixedly surrounded on the circumferential side of the shaft tube 4. The upper limit plate 3 and the lower limit plate 5 are parallel. The liquid adding ring tube 6 surrounds the outside of the shaft tube 4 and abuts between the upper limit plate 3 and the lower limit plate 5, so that the shaft tube 4 can rotate smoothly relative to the liquid adding ring tube 6, and during the rotation process, the shaft tube 4 and the liquid adding ring tube 6 always maintain a sealed connection, that is, the liquid medicine can be continuously introduced into the shaft tube 4 during rotation. As Figure 3 , the implementation method can be that an annular hole 601 is opened on the inner ring surface of the liquid adding ring tube 6, and a plurality of water passing holes 401 are circumferentially opened at the position of the shaft tube 4 facing the annular hole 601. An upper sealing ring 9 and a lower sealing ring 10 are also arranged between the liquid adding ring tube 6 and the shaft tube 4, respectively located on the upper and lower sides of the annular hole 601. When the motor drives the shaft tube 4 to rotate, the liquid adding ring tube 6 can remain stationary, and each annular hole 601 always rotates within the area of the annular hole 601, so as to maintain a connected state. Also, due to the sealing effect of the upper sealing ring 9 and the lower sealing ring 10, the liquid medicine flowing out of the annular hole 601 is not easy to seep out of the inner ring surface of the liquid adding ring tube 6.

[0038] A plurality of blade units 7 are equidistantly arranged in a ring on the circumferential side of the shaft tube 4. Each blade unit 7 is perpendicular to the shaft tube 4. Looking along the axial direction of the shaft tube 4, the included angle between adjacent blade units 7 is 120°, and every three blade units 7 form a circle. The three blade units 7 in each circle can be of the same height or of different heights. In this embodiment, it is preferably of different heights. For example, along a clockwise or counterclockwise rotation direction, the heights of the three blade units 7 on the shaft tube 4 decrease in turn. Such a setting improves the coverage of all the blade units 7 in height. When applied, it can cover multiple height areas in the water and improve the dispersion efficiency of the liquid medicine in the water.

[0039] As Figure 1 , each slurry unit includes a buoyancy valve 71, a frame tube 72 and three rotating tubes 73. The frame tube 72 includes an upper cross tube 721, a vertical tube 722 and a lower cross tube 723 connected in sequence, and the cross sections are all square. In other embodiments, they can also be all circular. In this embodiment, the buoyancy valve 71 communicates with the upper cross tube 721, the upper cross tube 721 communicates with the shaft tube 4, and the lower cross tube 723 does not communicate with the shaft tube 4. In other embodiments without the buoyancy valve 71, the lower cross tube 723 can also communicate with the shaft tube 4. In some embodiments, the buoyancy valve 71 can also communicate with the lower cross tube 723, then it can be set that the upper cross tube 721 does not communicate with the shaft tube 4, and the lower cross tube 723 communicates with the shaft tube 4.

[0040] As Figure 4, in this embodiment, three notches 7211 are formed on one side of the upper horizontal pipe 721 opposite to the lower horizontal pipe 723, that is, three recessed grooves are formed by the inward depression of one side of the upper horizontal pipe 721 relative to the lower horizontal pipe 723. The middle of the bottom of each recessed groove is open, and the bottom does not need to be fully open, forming the notch 7211 for water passage. Three grooves 7231 are formed on one side of the lower horizontal pipe 723 opposite to the upper horizontal pipe 721, and the three grooves 7231 can be sealed at the bottom without water passage. When the shaft pipe 4 is placed vertically, in the vertical direction, each notch 7211 is aligned with one groove 7231.

[0041] As Figure 1 , each rotating pipe 73 includes an intermediate pipe 731 and three identical horizontal arc-shaped pipes 732. The intermediate pipe 731 can be cylindrical. The cross-section of the horizontal arc-shaped pipe 732 can be circular or square.

[0042] The inner end of each horizontal arc-shaped pipe 732 communicates with the intermediate pipe 731, and the outer end is the liquid outlet 7321. The three horizontal arc-shaped pipes 732 are equidistantly arranged on the circumference of the intermediate pipe 731, and the three liquid outlets 7321 are located on the same circumference. The concave surface of each horizontal arc-shaped pipe 732 faces the convex surface of the adjacent horizontal arc-shaped pipe 732, so that the centrifugal directions of the outlets of the three horizontal arc-shaped pipes 732 complement each other. When spraying the liquid medicine, they can jointly push the rotating pipe 73 to rotate in one direction. The upper end of the intermediate pipe 731 is inserted into the notch 7211 and communicates with the notch 7211. The lower end of the intermediate pipe 731 is inserted into the groove 7231. The lower end of the intermediate pipe 731 is not connected to the shaft pipe 4. It can be that the lower end of the intermediate pipe 731 is closed, or the groove 7231 is closed, or the connection between the lower horizontal pipe 723 and the shaft pipe 4 is closed.

[0043] As Figure 5, the buoyancy valve 71 includes a counterweight 711, a float 712, a conduit 713, and a box 714. The box 714 can be square and is fixed to the side of the shaft tube 4. Water injection holes 7141 can be opened on each surface of the box 714. The conduit 713 can be square. The upper end of the conduit 713 communicates with the middle position of the lower surface of the box 714, and the lower end of the conduit 713 communicates with the upper surface of the upper horizontal tube 721. There is also a downward protrusion 7212 on the lower surface of the upper horizontal tube 721. The protrusion 7212 is also square. The cross-sectional shape and size of the protrusion 7212 and the conduit 713 are the same. Both the counterweight 711 and the float 712 are square, and the counterweight 711 and the float 712 are connected and fixed by a connecting rod. When the box 714 is not filled with water, the lower one-third of the counterweight 711 is located in the protrusion 7212, the middle one-third is located in the main body of the upper horizontal tube 721, the upper one-third is located in the conduit 713, and there is still a space equivalent to two-thirds of the height of the counterweight 711 left in the upper part of the conduit 713. The float 712 is located at the bottom of the box 714, and there is still a space equivalent to two-thirds of the height of the counterweight 711 left in the upper part of the box 714. When the box 714 is filled with water, the float 712 drives the counterweight 711 to float upward. The float 712 floats up to abut against the inner top surface of the box 714. At this time, the counterweight 711 just disengages from the upper horizontal tube 721 and is completely located in the conduit 713. In order to facilitate the upward floating of the float 712, water injection holes 7141 can also be opened at the upper two-thirds height position of the conduit 713.

[0044] The liquid adding and stirring device can be used for the hardness removal treatment of high-hardness wastewater. When in use: insert the shaft tube 4 and the blade unit 7 of the liquid adding and stirring device into the wastewater, the rotator 2 drives the shaft tube 4 to rotate, and the blade unit 7 rotates along with the shaft tube 4; the liquid adding pump 83 extracts the liquid medicine in the liquid medicine tank 81 into the liquid adding ring pipe 6, and the liquid medicine enters the shaft tube 4 through the annular hole 601 and the water passing hole 401; for the blade unit 7 with the buoyancy valve 71 immersed in the wastewater, the buoyancy valve 71 opens the channel between the shaft tube 4 and the upper horizontal tube 721, the liquid medicine entering the shaft tube 4 enters the upper horizontal tube 721, then enters the rotating tube 73, and is sprayed out from the three liquid outlets 7321 of the rotating tube 73, and the liquid medicine is evenly dispersed in the wastewater; for the blade unit 7 with the buoyancy valve 71 not immersed in the wastewater, the buoyancy valve 71 closes the channel between the shaft tube 4 and the upper horizontal tube 721, so that the liquid medicine cannot enter this blade unit 7, that is, the blade unit 7 on the water surface does not spray out the liquid medicine, will not block the liquid outlet 7321 due to the drying of the liquid medicine, and the liquid medicine will not be sprayed out of the reaction tank 15 containing the wastewater or sprayed on the inner wall of the reaction tank 15 and solidify, reducing the waste of the liquid medicine and the trouble of cleaning. The liquid medicine sprayed out from the liquid outlet 7321 is first efficiently dispersed in the wastewater at this position due to the rotation of the rotating tube 73, and at the same time is dispersed in the wastewater at each circumferential height due to the revolution of the blade unit 7. The multiple blade units 7 are arranged in a scattered manner at different heights, covering multiple heights of the reaction tank 15, so that the liquid medicine is efficiently dispersed in the wastewater, improving the hardness removal reaction efficiency. Embodiment 2

[0045] Such as Figure 6 , a softening direct filtration system includes the liquid adding and stirring device of Embodiment 1, and also includes a wastewater pipe 11, a pre-sedimentation and regulation tank 12, a front pipeline 13, a front pump 14, a reaction tank 15, a rear pipeline 16, a pressure pump 17 and a direct filtration device 18.

[0046] The bracket 1 of the liquid adding and stirring device is arranged on the periphery and above of the reaction tank 15, and the shaft tube 4 and the blade unit 7 extend into the reaction tank 15.

[0047] The wastewater pipe 11 injects the external wastewater into the pre-sedimentation and regulation tank 12. Through static settlement, most of the sediment settles down. The front pipe 13 is connected to the pre-sedimentation and regulation tank 12 and the reaction tank 15. The upper-layer wastewater is pumped into the reaction tank 15 through the front pump 14 installed on the front pipe 13. After the pumping is completed, the rotator 2 is started to stir the wastewater. The liquid addition pump 83 pumps the liquid medicine in the liquid medicine tank 81 into the liquid addition ring pipe 6, and then into the shaft pipe 4. As described in the first embodiment, the liquid medicine is sprayed out from the liquid outlet 7321 into the wastewater, and fully reacts with the calcium ions and magnesium ions in the wastewater to generate calcium carbonate and magnesium hydroxide precipitates. The rear pipe 16 is connected to the reaction tank 15 and the direct filtration device 18. After the reaction is completed, the pressure pump 17 installed on the rear pipe 16 is started, and the wastewater with flocculants or particulate matter precipitates after hardness removal is passed through the direct filtration device 18 for high-efficiency filtration, completing the hardness removal and turbidity removal of high-hardness and high-turbidity wastewater.

[0048] The inside of the direct filtration device 18 uses a direct filtration softening membrane for filtration. The direct filtration softening membrane is made of PTFE material and is formed by a special process. The pore size of the filter membrane can reach 0.01μm - 5μm. Through pressurized filtration at 0.2 - 0.3 Mpa, the precipitates and suspended substances in the water can be intercepted, reducing the turbidity of the water. The filtered purified water can be directly discharged or enter the subsequent advanced treatment system according to different environmental protection requirements.

[0049] The above embodiments of the simultaneous hardness removal and turbidity removal treatment process for sewage adopt the innovative process route of "chemical softening + direct filtration softening membrane", simplifying the traditional multiple treatment sections into one section to meet the discharge requirements. The filtration flux is 30 - 50 LMH, which can intercept the precipitates and suspended substances in the water, reduce the turbidity of the water. After treatment, the hardness of the effluent can be reduced to 0.15 - 0.2 mmol, the content of Ca2+ and Mg2+ ions is less than 50 mg / L, and the turbidity can be reduced to ≤0.5 NTU.

[0050] Although the present application has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A liquid adding and stirring device, characterized in that, It includes a liquid adding loop pipe (6), a shaft pipe (4), a rotator (2), and multiple blade units (7); the rotator (2) is connected to the shaft pipe (4); the liquid adding loop pipe (6) is sleeved outside the shaft pipe (4); in a state where the rotator (2) drives the shaft pipe (4) to rotate, the liquid adding loop pipe (6) remains in a seamless communication state with the shaft pipe (4); each blade unit (7) is connected to the shaft pipe (4). Each blade unit (7) includes a frame pipe (72) and several rotating pipes (73); one end of the frame pipe (72) communicates with the shaft pipe (4), and the other end is connected to the shaft pipe (4); the frame pipe (72) has a combination of several relative notches (7211) and grooves (7231); the shaft pipe (4) leads to each notch (7211); one end of each rotating pipe (73) always communicates with the notch (7211), and the other end is inserted into the groove (7231); the rotating pipe (73) has multiple liquid outlets (7321).

2. The liquid adding and stirring device according to claim 1, characterized in that, The rotating pipe (73) includes an intermediate pipe (731) and three identical horizontal arc pipes (732). The inner ends of the three horizontal arc pipes (732) communicate with the intermediate pipe (731); the concave surface of each horizontal arc pipe (732) faces the convex surface of the adjacent horizontal arc pipe (732); the outer end of the horizontal arc pipe (732) is the liquid outlet (7321). The upper end of the intermediate pipe (731) is inserted into the notch (7211) and communicates with the notch (7211), and the lower end of the intermediate pipe (731) is inserted into the groove (7231); the lower end of the intermediate pipe (731) is not communicated with the shaft pipe (4).

3. The liquid adding and stirring device according to claim 1 or 2, characterized in that, The blade unit (7) further includes a buoyancy valve (71); the buoyancy valve (71) includes a counterweight (711), a float (712), a conduit (713), and a box (714). The frame pipe (72) includes an upper cross pipe (721), a vertical pipe (722), and a lower cross pipe (723) connected in sequence; the upper cross pipe (721) communicates with the shaft pipe (4), and the lower cross pipe (723) is not communicated with the shaft pipe (4); the upper cross pipe (721) is provided with the notch (7211); the lower cross pipe (723) is provided with the groove (7231). The box (714) is fixed to the shaft tube (4); the upper end of the conduit (713) communicates with the box (714), and the lower end communicates with the upper surface of the upper horizontal tube (721); the float (712) is installed in the box (714); the counterweight (711) is installed in the frame tube (72) and the conduit (713); the float (712) is connected to the counterweight (711); the box (714) has a plurality of water filling holes (7141); when the box (714) is not filled with water, the counterweight (711) cuts off the frame tube (72); when the box (714) is filled with water, the float (712) floats to the top of the box (714), the counterweight (711) releases the cut-off of the frame tube (72), and at least a part of the counterweight (711) is located in the conduit (713).

4. The liquid adding and stirring device according to claim 3, characterized in that, The lower surface of the frame tube (72) has a downward protruding lower convex part (7212); when the box (714) is not filled with water, the lower end of the counterweight (711) is embedded in the lower convex part (7212), and the upper end is located in the conduit (713).

5. The liquid adding and stirring device according to claim 4, characterized in that, The counterweight (711) is square; the main cross-section of the frame tube (72) is square; the conduit (713) is square; the counterweight (711) slides fittingly in the frame tube (72) and the conduit (713).

6. The liquid adding and stirring device according to claim 1, characterized in that, On the periphery of the liquid adding and stirring device, three of the paddle units (7) are arranged in each circle, the adjacent paddle units (7) are spaced 120°, and the three paddle units (7) are arranged from high to low along a rotation direction.

7. The liquid adding and stirring device according to claim 1, characterized in that, The liquid adding and stirring device includes an upper limit plate (3) and a lower limit plate (5); the upper limit plate (3) is fixed to the upper end of the shaft tube (4); the lower limit plate (5) is fixedly surrounded on the periphery of the shaft tube (4); the rotator (2) is connected to the upper limit plate (3); the liquid adding annular tube (6) abuts between the upper limit plate (3) and the lower limit plate (5); the inner ring surface of the liquid adding annular tube (6) has an annular hole (601); the periphery of the shaft tube (4) has a plurality of water passing holes (401); the annular hole (601) is aligned with the plurality of water passing holes (401); an upper sealing ring (9) and a lower sealing ring (10) are arranged between the liquid adding annular tube (6) and the shaft tube (4), and are respectively located on the upper and lower sides of the annular hole (601).

8. The liquid adding and stirring device according to claim 7, characterized in that, The liquid adding and stirring device further includes a bracket (1) and a plurality of liquid adding mechanisms (8); the rotator (2) is fixed on the bracket (1); each liquid adding mechanism (8) includes a liquid medicine tank (81), a liquid adding pipe (82), a liquid adding pump (83) and a one-way valve (84); the liquid medicine tank (81) is fixed on the bracket (1); one end of the liquid adding pipe (82) communicates with the liquid medicine tank (81), and the other end communicates with the liquid adding annular tube (6); the liquid adding pump (83) and the one-way valve (84) are both installed on the liquid adding pipe (82).

9. A softening direct filtration system, characterized in that, The liquid adding and stirring device according to any one of claims 1-8 further includes a wastewater pipe (11), a pre-sedimentation and regulation tank (12), a front pipeline (13), a front pump (14), a reaction tank (15), a rear pipeline (16), a pressure pump (17) and a direct filtration device (18); the wastewater pipe (11) leads to the pre-sedimentation and regulation tank (12); the pre-sedimentation and regulation tank (12) leads to the reaction tank (15) through the front pipeline (13); the front pump (14) is installed on the front pipeline (13); the reaction tank (15) leads to the direct filtration device (18) through the rear pipeline (16); the pressure pump (17) is installed on the rear pipeline (16); the shaft pipe (4) and multiple blade units (7) of the liquid adding and stirring device extend into the reaction tank (15).

Images