A sludge chemical conditioning multi-stage mixing device and process

Abstract

The present application discloses a multi-stage mixing device and process for chemical conditioning of sludge, which relates to the technical field of sludge conditioning. The multi-stage mixing device for chemical conditioning of sludge includes a sludge tank, wherein the sludge tank has a mixing tank, and further includes a stirring device, wherein the stirring device includes a driving member, a rotating member, and a plurality of stirring impellers, wherein the plurality of stirring impellers are all arranged on the rotating member, and the driving member drives the rotating member to rotate; further includes a plurality of feeding devices, wherein the feeding device includes a hopper, a feeding pipe, a discharge member, and a plurality of filter screens, wherein the discharge member has a cavity inside, the discharge member is provided with a plurality of discharge ports, and the plurality of filter screens respectively cover the plurality of discharge ports; and there is a clearance space between adjacent stirring impellers to provide clearance for the discharge member. The present application can improve the efficiency of feeding the conditioning agent into the sludge tank, ensure that the conditioning agent and the sludge are efficiently and fully mixed, and reduce the probability that the conditioning agent cannot be fed in due to sludge blockage.

Description

Technical Field

[0001] This application relates to the technical field of sludge conditioning, and particularly to a multi-stage mixing device and process for chemical conditioning of sludge. Background Technique

[0002] Sludge conditioning refers to the measures of pre-treating sludge to improve the thickening and dewatering efficiency of sludge and to improve the properties of sludge systematically for subsequent treatment economically. There are four common sludge conditioning methods: chemical conditioning method, heat treatment method, freezing method, and elutriation method. Among them, the chemical conditioning method is usually realized based on a multi-stage mixing device for chemical conditioning of sludge.

[0003] The existing multi-stage mixing devices for chemical conditioning of sludge generally achieve the purpose by sequentially adding various conditioning agents into the sludge pool, and another conditioning agent needs to be added after one conditioning agent is fully mixed with the sludge in the sludge pool. To improve the efficiency of the full mixing of the conditioning agent and the sludge after the addition of the conditioning agent, the outlet of the feeding pipeline usually extends into the sludge pool and into the sludge, so as to accelerate the diffusion rate of the conditioning agent in the sludge, thereby improving the efficiency of the full mixing of the conditioning agent and the sludge.

[0004] However, after the outlet of the feeding pipeline remains extended into the sludge for a long time, the outlet of the feeding pipeline is likely to be blocked by the sludge. When the outlet of the feeding pipeline is partially blocked by the sludge, it will affect the efficiency of adding the conditioning agent into the sludge pool, thereby prolonging the time required for the full mixing of the conditioning agent and the sludge; when the outlet of the feeding pipeline is completely blocked by the sludge, the conditioning agent cannot be added into the sludge pool, resulting in the inability of the multi-stage mixing device for chemical conditioning of sludge to chemically condition the sludge. Summary of the Invention

[0005] This application provides a multi-stage mixing device and process for chemical conditioning of sludge, which can improve the efficiency of adding the conditioning agent into the sludge pool, ensure the high-efficiency and full mixing of the conditioning agent and the sludge, and reduce the probability that the conditioning agent cannot be added due to blockage by the sludge.

[0006] On the one hand, this application provides a multi-stage mixing device for chemical conditioning of sludge, adopting the following technical solution:

[0007] A multi-stage mixing device for chemical conditioning of sludge includes a sludge pool, which has a mixing tank with an upward opening. It further includes a stirring device, which includes a driving member, a rotating member, and a plurality of stirring impellers. The plurality of stirring impellers are all arranged on the rotating member and located in the mixing tank. The rotating member is rotatably connected to the sludge pool and its rotation axis is vertical. The driving member is arranged on the sludge pool, and the driving member drives the rotating member to rotate;

[0008] It also includes a plurality of feeding devices, and the plurality of feeding devices are used to feed a plurality of conditioning agents into the mixing tank; the feeding device includes a silo, a feeding pipe, a discharge piece, and a plurality of filter screens, one end of the feeding pipe is connected to the silo, and the other end of the feeding pipe is located in the mixing tank, the discharge piece is arranged at the end of the feeding pipe away from the silo, the interior of the discharge piece has a cavity communicating with the feeding pipe, the surface of the discharge piece is provided with a plurality of discharge ports in different directions, the discharge ports are communicated with the cavity, and the plurality of filter screens are all arranged on the discharge piece and respectively cover the plurality of discharge ports;

[0009] The discharging member is located on one side of the rotating member, and there is a clearance space between adjacent stirring impellers for providing clearance for the discharging member.

[0010] By adopting the above technical solution, when the conditioning agent is added to the sludge through the feeding device, the conditioning agent can leave the discharge piece from multiple discharge ports and mix with the sludge, thereby facilitating the diffusion of the conditioning agent in the sludge and improving the mixing efficiency; the conditioning agent can pass through the filter and enter the sludge, and the water in the sludge can pass through the filter and enter the cavity, and the conditioning agent can also be conveniently mixed with the sludge after mixing with water; at the same time, the filter can effectively prevent the sludge from entering the cavity and forming a blockage, thereby reducing the probability of the feeding device being blocked by the sludge; in addition, the stirring device can stir the sludge in the mixing tank when working, accelerating the efficiency of its full mixing with the input conditioning agent; and, during the rotation of the several stirring impellers, when the sludge is stirred and passes around the discharge piece, the speed of the conditioning agent entering the sludge through the feeding device can be accelerated; when the sludge forms a blockage on the filter, the stirring impeller can remove the sludge from the filter during the process of stirring the sludge, achieving a clearing effect, thereby reducing the probability of the conditioning agent being unable to be fed due to sludge blockage.

[0011] Optionally, the stirring impeller includes a plurality of blades, and the blades are arranged obliquely relative to the rotation axis of the rotating member; when the driving member drives the rotating member to rotate, the stirring impeller stirs the sludge and drives the sludge to move toward the direction close to the opening of the mixing tank.

[0012] By adopting the above technical solution, when the impeller rotates to stir the sludge, the impeller can drive the sludge in contact with it to move upward, thereby reducing the phenomenon of sludge sinking to the bottom, improving the stirring effect of the stirring device on the sludge, and further improving the efficiency of fully mixing the conditioner and the sludge.

[0013] Optionally, a plurality of sieve holes are provided on the blades, the apertures of the sieve holes on the blades of the same stirring impeller are the same, the apertures of the sieve holes on the blades of different stirring impellers are different, and the apertures of the sieve holes on the blades close to the mixing tank opening are larger than the apertures of the sieve holes on the blades away from the mixing tank opening.

[0014] By adopting the above technical solution, the sieve holes provided on the blades can reduce the resistance that the impeller needs to overcome when rotating to stir the sludge, thereby reducing the probability of the blades being damaged due to excessive sludge resistance; and, during the rotation of the impeller, for the sludge affected by the blade force, most of the sludge will directly pass through the sieve holes and leave the blade end surface, while some flocculent sludge will be decomposed into sludge of a size that can pass through the sieve holes under the action of the blades, and as the sludge moves from the bottom to the top, the size of the sludge particles will gradually decrease, thereby further improving the efficiency of the thorough mixing of the conditioner and the sludge.

[0015] Optionally, the stirring impeller further includes a plurality of intercepting members, which are respectively arranged on a plurality of the blades and located on the end surfaces of the blades that are in contact with the sludge.

[0016] By adopting the above technical solution, during the rotation of the stirring impeller, when the blades come into contact with the sludge, impurities such as branches mixed in the sludge can be intercepted by a number of intercepting parts, so that the impurities such as branches can be fixed in position on the blades and move with the blades, thereby reducing the impact of impurities such as branches floating in the mixing tank on the full mixing of the conditioner and the sludge; in addition, the several intercepting parts can increase the roughness of the side of the blade that exerts force on the sludge, thereby improving the ability of the blade to decompose flocculent sludge.

[0017] Optionally, the intercepting member has a plurality of protrusions, and an intercepting space is formed between adjacent protrusions on the same intercepting member.

[0018] By adopting the above technical solution, impurities such as branches will be intercepted by a number of intercepting parts in a state where part of themselves is stuck in the interception space, which can improve the position stability of impurities such as branches on the blades after being intercepted by the number of intercepting parts, and at the same time reduce the probability of impurities such as branches clogging the sieve holes; in addition, after impurities such as branches are fixed in position on the blades, the roughness of the side of the blade that exerts force on the sludge can be further increased, thereby further improving the ability of the blade to decompose flocculent sludge.

[0019] Optionally, a plurality of blades on adjacent stirring impellers are staggered and distributed along the rotation axis of the rotating member.

[0020] By adopting the above technical solution, the stirring effect of the sludge can be improved when several stirring impellers rotate synchronously, so that the stirring effect of the stirring device on the sludge is more uniform, thereby reducing the stirring dead angle and further improving the mixing effect of the conditioner and the sludge.

[0021] Optionally, the discharging member is rotatably connected to the feeding pipe, and its rotation axis is perpendicular to the rotation axis of the rotating member. The surface of the discharging member has a plurality of driving plates. When the stirring device stirs the sludge, the plurality of driving plates are forced to drive the discharging member to rotate.

[0022] By adopting the above technical solution, during the process of the stirring device operating to stir the sludge, when the sludge moves past the periphery of the discharging member, the sludge will exert a force on the plurality of driving plates, thereby driving the discharging member to rotate relative to the feeding pipe; during the rotation of the discharging member, the conditioner in the cavity can be thrown out under the centrifugal force, helping the conditioner to enter the sludge. At the same time, it can increase the diffusion range of the conditioner in the sludge and make the conditioner more evenly put into the sludge, thereby further improving the efficiency of the full mixing of the conditioner and the sludge; in addition, when the discharging member rotates, the sludge blocked on the filter screen can also be thrown out under the centrifugal force, which can also achieve the effect of removing blockage, thereby further reducing the probability of the sludge blocking the filter screen for a long time.

[0023] Optionally, the driving plate is inclined relative to the tangent line of its position on the discharging member, and the plurality of driving plates are forced to drive the discharging member to rotate unidirectionally.

[0024] By adopting the above technical solution, during the process of the stirring device operating to stir the sludge, it can make the tendency of the force exerted by the moving sludge on the plurality of driving plates to drive the discharging member to rotate in one direction remain greater than the tendency to drive the discharging member to rotate in the other direction, so that the discharging member can rotate stably and unidirectionally when the stirring device is operating, enabling the force exerted by the moving sludge on the plurality of driving plates to be effectively utilized, increasing the rotation speed of the discharging member, and further improving the beneficial effects brought by the rotation of the discharging member.

[0025] Optionally, the feeding device further includes a plurality of blockage removing members, and the plurality of blockage removing members are located in the cavity; when the discharging member rotates, the blockage removing members move in the cavity.

[0026] By adopting the above technical solution, the plurality of blockage removing members move in the cavity along with the rotation of the discharging member. When the plurality of blockage removing members move, they can make the movement tendency of the conditioner in the cavity stronger, thereby further accelerating the speed of the conditioner leaving the cavity through the discharging port, and further improving the efficiency of the full mixing of the conditioner and the sludge; when the sludge blocks part of the filter screen, after the blockage removing members move and contact the blocked filter screen, the impact generated by the blockage removing members on it can shake off the sludge blocked on the filter screen, achieving the effect of removing blockage, thereby further reducing the probability of the sludge blocking the filter screen.

[0027] On the other hand, the present application provides a multi-stage mixing process for chemical conditioning of sludge, adopting the following technical solution:

[0028] A multi-stage mixing process for sludge chemical conditioning, which is realized based on the above-mentioned multi-stage mixing equipment for sludge chemical conditioning, and the specific steps are as follows:

[0029] Place the sludge into the mixing tank of the sludge pool, and at the same time, put the liquid conditioner into the sludge through one of the feeding devices to complete the first-stage mixing with the sludge;

[0030] Start the stirring device, and at the same time, continue to put the liquid conditioner into the sludge through one of the feeding devices to achieve the second-stage mixing;

[0031] Stop putting the liquid conditioner, and instead put the powder conditioner into the sludge through another feeding device, and complete the third-stage mixing under the stirring action of the stirring device.

[0032] By adopting the above technical solution, after the stirring device is started, the probability of clogging of the feeding device caused by the sludge and the conditioner is greatly reduced, ensuring that the conditioner can be smoothly put into the sludge, thereby ensuring the efficiency of the full mixing of the conditioner and the sludge, and further enabling the process based on the above-mentioned multi-stage mixing equipment for sludge chemical conditioning to proceed stably.

[0033] In summary, the present application includes at least one of the following beneficial effects:

[0034] 1. It can improve the efficiency of putting the conditioner into the sludge pool, ensure the efficient and full mixing of the conditioner and the sludge, and reduce the probability that the conditioner cannot be put in due to sludge clogging;

[0035] 2. It can decompose the flocculent sludge and larger sludge particles into smaller sludge particles, thereby improving the efficiency of the full mixing of the conditioner and the sludge;

[0036] 3. It can fix impurities such as branches doped in the sludge at a fixed position on the blades, reduce its influence on the full mixing of the conditioner and the sludge, and can strengthen the ability of the blades to decompose the sludge, and at the same time can reduce the probability of clogging of the sieve holes caused by impurities such as branches;

[0037] 4. It can improve the diffusion effect of the conditioner in the sludge and the speed of putting it into the sludge, and when the sludge clogs the filter screen, it can spontaneously clean the clogging of the sludge. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a schematic structural diagram of a multi-stage mixing equipment for sludge chemical conditioning according to an embodiment of the present application;

[0039] Figure 2 is Figure 1 a partial cross-sectional view along the line A-A in

[0040] Figure 3 is a schematic structural diagram of the stirring device in an embodiment of the present application;

[0041] Figure 4 This is a schematic structural diagram of a feeding device in an embodiment of the present application;

[0042] Figure 5 yes Figure 2 Partial cross-sectional view along line BB.

[0043] Explanation of the accompanying reference numerals: 1. Sludge pool; 11. Mixing tank; 111. Inclined surface; 2. Stirring device; 21. Driving member; 22. Rotating member; 23. Stirring impeller; 231. Blade; 2311. Sieve hole; 232. Intercepting member; 2321. Protrusion; 2322. Intercepting space; 24. Make way space; 3. Feeding device; 31. Silo; 32. Feeding pipe; 33. Discharging member; 331. Cavity; 332. Discharging port; 34. Feeding member; 35. Filter screen; 36. Driving plate; 37. Blocking member; 4. Sewage inlet device; 41. Sewage inlet pipe; 42. Sewage inlet pump; 5. Sewage discharge device; 51. Sewage discharge pipe; 52. Sewage discharge pump. DETAILED DESCRIPTION

[0044] The following is combined with Figures 1-5 This application is described in further detail.

[0045] The embodiment of the present application discloses a multi-stage mixing device for chemical conditioning of sludge, which is used for pre-treating sludge to improve the concentration and dehydration efficiency of the sludge. Multi-stage mixing is achieved by sequentially adding different conditioning agents and fully mixing them with the sludge.

[0046] Reference Figure 1 The sludge chemical conditioning multi-stage mixing equipment includes a sludge tank 1, a stirring device 2 and a plurality of feeding devices 3. The sludge tank 1 provides a place for fully mixing the sludge and the conditioning agent; the stirring device 2 is used to stir the sludge to improve the efficiency of fully mixing the conditioning agent and the sludge; the feeding device 3 is used to put a certain dose of conditioning agent into the sludge tank 1 to fully mix it with the sludge, and different feeding devices 3 correspond to different types of conditioning agents. After the sludge to be pretreated is sent into the sludge tank 1, different conditioning agents are added to the sludge tank 1 by controlling different feeding devices 3, and the sludge is stirred by controlling the stirring device 2 so that the conditioning agent and the sludge are fully mixed, thereby achieving chemical conditioning multi-stage mixing of the sludge. In this embodiment, it is preferred that two conditioning agents are added in total during the process of chemical conditioning multi-stage mixing of the sludge, so the sludge chemical conditioning multi-stage mixing equipment includes two feeding devices 3 in total.

[0047] The sludge tank 1 is fixed on the ground. There is a mixing tank 11 with an opening facing vertically upward on the sludge tank 1. The mixing tank 11 provides sufficient space for the full mixing of the conditioner and the sludge. The multi-stage sludge chemical conditioning mixing device further includes a sludge inlet device 4 for feeding the sludge to be treated into the mixing tank 11 and a sewage discharge device 5 for discharging the pretreated sludge. The sludge inlet device 4 and the sewage discharge device 5 are respectively located on both sides of the sludge tank 1.

[0048] Among them, the sludge inlet device 4 includes a sludge inlet pipe 41 and a sludge inlet pump 42. One end of the sludge inlet pipe 41 is fixedly connected to the sludge tank 1 and penetrates into the sludge tank 1 to communicate with the mixing tank 11, and the position where it communicates with the mixing tank 11 is close to the opening position of the mixing tank 11; the other end of the sludge inlet pipe 41 is fixedly connected to a sludge collection device (omitted in the drawing) and communicates with it. The sludge inlet pump 42 is fixedly installed on the sludge inlet pipe 41, and the sludge inlet pump 42 can drive the sludge to enter the mixing tank 11 along the sludge inlet pipe 41. Since the above-mentioned sludge inlet device 4 is a common prior art in this field, it will not be elaborated here, and the relevant structures in the drawing are only briefly shown.

[0049] The structure of the sewage discharge device 5 is similar to that of the sludge inlet device 4. The sewage discharge device 5 includes a sewage discharge pipe 51 and a sewage discharge pump 52. One end of the sewage discharge pipe 51 is fixedly connected to the sludge tank 1 and penetrates into the sludge tank 1 to communicate with the mixing tank 11, and the position where it communicates with the mixing tank 11 is close to the bottom position of the mixing tank 11; the other end of the sewage discharge pipe 51 is fixedly connected to the next-stage sludge treatment device (omitted in the drawing) and communicates with it. The sewage discharge pump 52 is fixedly installed on the sewage discharge pipe 51, and the sewage discharge pump 52 can drive the sludge in the mixing tank 11 to be discharged along the sewage discharge pipe 51. Since the above-mentioned sewage discharge device 5 is a common prior art in this field, it will not be elaborated here, and the relevant structures in the drawing are only briefly shown.

[0050] Refer to Figure 2 and Figure 3 As shown in, the stirring device 2 includes a driving member 21, a rotating member 22 and a plurality of stirring impellers 23. Among them, the rotating member 22 is a cylindrical structure as a whole. The rotating member 22 is located in the mixing tank 11 with its axis vertical. The rotating member 22 is rotatably connected to the sludge tank 1 and the axis of rotation of the rotating member 22 coincides with its own axis. Preferably, the shape of the mixing tank 11 is a cylindrical structure as a whole, the axis of the mixing tank 11 is vertical, and the axis of the rotating member 22 coincides with the axis of the mixing tank 11.

[0051] A plurality of stirring impellers 23 are respectively sleeved and fixed on the rotating member 22, and the plurality of stirring impellers 23 are equally spaced along the axis direction of the rotating member 22. In this embodiment, for the convenience of expression, it is preferably that the stirring device 2 includes a total of two stirring impellers 23. In other embodiments, the number of stirring impellers 23 can also be more.

[0052] The stirring impeller 23 includes a plurality of blades 231. The plurality of blades 231 are all located on the circumferential side of the rotating member 22 and extend outward in a direction approaching the circumferential side wall of the mixing tank 11. The plurality of blades 231 are circumferentially arrayed around the rotating member 22 with the axis of the rotating member 22 as the axis. In this embodiment, preferably, the stirring impeller 23 includes three blades 231 in total. In other embodiments, the number of blades 231 included in the stirring impeller 23 can also be more.

[0053] The driving member 21 is located on one side in the axial direction of the rotating member 22, and the driving member 21 is fixedly connected to the rotating member 22. Preferably, the driving member 21 is located above the sludge tank 1, and the top of the sludge tank 1 has a support structure for fixedly installing the driving member 21. Preferably, the driving member 21 is a servo motor, and the output end of the driving member 21 is fixedly connected to the upper end of the rotating member 22. The driving member 21 drives the rotating member 22 to rotate.

[0054] During the process that the driving member 21 drives the rotating member 22 to rotate, the distance between the end of the blade 231 far from the rotating member 22 and the circumferential side wall of the mixing tank 11 remains the same. There is an inclined surface 111 at the edge position of the bottom wall of the mixing tank 11, and the end of the inclined surface 111 close to the axis of the mixing tank 11 is the lower end of the inclination. For the stirring impeller 23 close to the bottom of the mixing tank 11, the end of its blade 231 far from the rotating member 22 approaches the lower end of the inclined surface 111. When the stirring device 2 starts to stir the sludge in the mixing tank 11, there is a stirring dead angle in the space between the blade 231 and the circumferential side wall of the mixing tank 11. The sludge in the stirring dead angle falls onto the inclined surface 111 under the action of its own gravity and moves downward along the inclined surface 111 to the bottom of the mixing tank 11, and finally can be stirred by the stirring impeller 23 close to the bottom of the mixing tank 11, thereby ensuring the stirring effect of the stirring device 2 on the sludge.

[0055] In addition, for the stirring impeller 23 close to the bottom of the mixing tank 11, there is also a certain distance between its blade 231 and the bottom wall of the mixing tank 11. During the process that the stirring impeller 23 rotates with the rotating member 22, there is no position interference between it and the bottom wall of the mixing tank 11, and at the same time, it can stir the sludge located on the bottom wall of the mixing tank 11.

[0056] Furthermore, preferably, the planes where the three blades 231 on the stirring impeller 23 are all inclined relative to the axis of the rotating member 22, and the inclination directions and angles are the same. During the rotation of the stirring impeller 23, while the blade 231 pushes the sludge in contact with it to move, it can also drive the sludge in contact with it to move in a direction approaching the opening of the mixing tank 11, thereby improving the stirring effect of the stirring device 2 on the sludge and reducing the deposition of the sludge due to its own gravity.

[0057] Further, it is preferable that the three blades 231 on the two stirring impellers 23 are staggeredly distributed along the axial direction of the rotating member 22, so as to effectively prevent the situation that when the blades 231 of the stirring impeller 23 near the bottom of the mixing tank 11 drive the sludge to move upward, the blades 231 of the stirring impeller 23 near the opening of the mixing tank 11 prevent the sludge below it from moving upward; at the same time, it can make the stirring of the sludge by the stirring device 2 more uniform, and further improve the stirring effect of the stirring device 2 on the sludge.

[0058] Further, it is preferable that a plurality of sieve holes 2311 are formed in the blade 231. The opening direction of the sieve holes 2311 is horizontal and perpendicular to the direction in which the blade 231 extends outward, and the opening positions of the plurality of sieve holes 2311 on the blade 231 are arranged in an array along the plane of the blade 231. It is preferable that the cross-section of the sieve hole 2311 is circular. During the process of the stirring impeller 23 rotating to drive the blade 231 to push the sludge to move together, the smaller sludge particles and water can leave the blade 231 through the sieve holes 2311, reducing the resistance required to overcome the rotation of the stirring impeller 23. At the same time, it can drive the flocculent sludge or larger sludge particles in the sludge contacting the blade 231 to pass through the sieve holes 2311 and decompose them into smaller sludge particles. Since the smaller sludge particles are more likely to be mixed and reacted with the conditioner, the sieve holes 2311 can further improve the efficiency of the full mixing of the conditioner and the sludge.

[0059] Furthermore, it is preferable that the aperture of the sieve holes 2311 on the blade 231 of the stirring impeller 23 near the bottom of the mixing tank 11 is larger than the aperture of the sieve holes 2311 on the blade 231 of the stirring impeller 23 near the opening of the mixing tank 11. Since the flocculent sludge and larger sludge particles have a greater mass than other sludge particles, they will mainly concentrate at the bottom of the mixing tank 11; during the rotation of the stirring impeller 23 near the bottom of the mixing tank 11, the flocculent sludge and larger sludge particles can be decomposed into smaller sludge particles first, and at the same time, the rotation of the stirring impeller 23 near the bottom of the mixing tank 11 will drive the sludge particles to move upward; during the rotation of the stirring blade 231 near the opening of the mixing tank 11, the decomposed flocculent sludge and larger sludge particles can be decomposed into smaller sludge particles. Thus, the flocculent sludge and larger sludge particles can be gradually decomposed into smaller sludge particles, reducing the probability of the sludge blocking the sieve holes 2311.

[0060] Further, the stirring impeller 23 further includes a plurality of intercepting members 232. The intercepting members 232 are integrally in a cylindrical structure. The plurality of intercepting members 232 are respectively fixedly installed on the three blades 231. The intercepting members 232 are fixedly connected to the end faces of the blades 231 that actively contact the sludge during movement. The axis of the intercepting members 232 is perpendicular to the plane where the blades 231 are located, and the installation positions of the plurality of intercepting members 232 on the blades 231 are arrayed on the end faces of the blades 231.

[0061] During the rotation of the stirring impeller 23, when the sludge contacts the plurality of intercepting members 232 on the blades 231, the intercepting members 232 can assist in decomposing flocculent sludge and sludge particles with larger sizes into sludge particles with smaller sizes. At the same time, after sundries such as branches doped in the sludge contact the blades 231, they can be stuck in the space between adjacent intercepting members 232, so that sundries such as branches can remain at fixed positions on the blades 231 during the startup of the stirring device 2, effectively reducing the effect of sundries such as branches floating in the mixing tank 11 and affecting the full mixing of the conditioner and the sludge.

[0062] Furthermore, preferably, the intercepting members 232 have a plurality of protruding portions 2321. The protruding portions 2321 are integrally in a spherical structure. The plurality of protruding portions 2321 are equidistantly distributed along the axis direction of the intercepting members 232. In this embodiment, preferably, each intercepting member 232 has two protruding portions 2321, and there is a spacing between the protruding portion 2321 near one end of the blade 231 and the blade 231.

[0063] An intercepting space 2322 is formed between the two protruding portions 2321 on the same intercepting member 232. When sundries such as branches are stuck in the space between adjacent intercepting members 232, part of the sundries such as branches will be stuck in the intercepting space 2322. At this time, the plurality of protruding portions 2321 contacting it will limit its movement, which can improve the position stability of sundries such as branches relative to the blades 231 after being stuck, and at the same time can reduce the probability of the sieve holes 2311 being blocked due to direct contact between sundries such as branches and the blades 231. And, after sundries such as branches are stuck on one side of the end face of the blades 231 that actively contact the sludge, when the sludge contacts the sundries such as branches, it can also assist in decomposing flocculent sludge and sludge particles with larger sizes into sludge particles with smaller sizes.

[0064] Refer to Figure 2 and Figure 4 , the feeding device 3 includes a silo 31, a feeding pipe 32, and a discharging member 33. The silo 31 contains a conditioner. Preferably, the silos 31 of the two feeding devices 3 respectively contain a liquid conditioner (a solution formed by mixing inorganic coagulants such as aluminum salts and iron salts with water) and a powdery conditioner (such as a polymer coagulant like polyacrylamide). The silo 31 is fixedly installed on both sides of the sludge tank 1 through a frame body, and preferably, the height of the position where the silo 31 is located is higher than that of the sludge tank 1.

[0065] One end of the feeding pipe 32 is fixedly connected to and communicates with the silo 31, while the other end of the feeding pipe 32 passes through the opening of the mixing tank 11 and is located within the mixing tank 11. A discharge member 33 is mounted at the end of the feeding pipe 32 away from the silo 31. Once the sludge to be treated has completely entered the mixing tank 11, both the discharge member 33 and the end of the feeding pipe 32 away from the silo 31 are immersed in the sludge. A clearance space 24 is provided between the two impellers 23 to accommodate the discharge member 33 and the end of the feeding pipe 32 away from the silo 31. As the impellers 23 rotate, their blades 231 pass over the upper and lower sides of the discharge member 33, respectively.

[0066] The feeding device 3 also includes a feeding member 34. One side of the feeding member 34 is fixedly connected to and communicates with the hopper 31, and the other side of the feeding member 34 is fixedly connected to and communicates with the feeding pipe 32. The feeding member 34 is used to drive the conditioning agent in the hopper 31 into the mixing tank 11 through the feeding pipe 32, and can also control the amount of conditioning agent added. Because the feeding member 34 is common in the art, it will not be described in detail here, and only a brief description is shown in the accompanying drawings.

[0067] The discharge piece 33 is spherical in structure as a whole, and has a cavity 331 inside. The cavity 331 is communicated with the end of the feeding pipe 32 away from the silo 31, and the shape of the cavity 331 is also spherical. A plurality of discharge ports 332 are also provided on the surface of the discharge piece 33, and the discharge ports 332 communicate the cavity 331 with the outside world. Even if the cavity 331 is communicated with the mixing tank 11, the plurality of discharge ports 332 are evenly distributed on the surface of the discharge piece 33, so that the conditioning agent can enter the sludge from different directions when being fed through the plurality of discharge ports 332, which facilitates the diffusion of the conditioning agent in the sludge, thereby improving the efficiency of the full mixing of the conditioning agent and the sludge.

[0068] The discharge device also includes several filters 35, each corresponding to a plurality of discharge ports 332. The filters 35 are fixedly mounted on the discharge member 33 and cover the corresponding discharge ports 332. The filters 35 intercept smaller sludge particles while allowing water and conditioning agents to pass through, thereby reducing the likelihood of sludge entering the feeding pipe 32 and causing blockage. For ease of illustration, the mesh size of the filters 35 is omitted in some figures.

[0069] When the feeding device 3 feeds the material into the mixing tank 11 and the stirring device 2 is started to help the conditioner and the sludge to be fully mixed, the conditioner is mainly located near the makeshift space 24 after entering the mixing tank 11. The rotation of the stirring impeller 23 can accelerate the diffusion of the conditioner in the mixing tank 11, and at the same time can stir the sludge, accelerate the contact between the sludge and the conditioner, and make the two fully mixed.

[0070] Moreover, when the sludge forms a blockage on the side of the filter screen 35 away from the cavity 331, during the rotation of the stirring impeller 23, when the blade 231 passes by the filter screen 35 blocked by the sludge, it can drive the sludge to leave the filter screen 35, thus achieving the effect of unclogging.

[0071] Furthermore, preferably, the discharging member 33 is rotatably connected to the feeding pipe 32. The rotation axis of the discharging member 33 is perpendicular to the rotation axis of the rotating member 22 and parallel to the feeding direction at the end of the feeding pipe 32 away from the silo 31, and the rotation axis of the discharging member 33 coincides with its own axis.

[0072] A number of driving plates 36 are fixedly installed on the surface of the discharging member 33. Preferably, the driving plates 36 are in the shape of an arc-shaped plate. The number of driving plates 36 is circumferentially arranged on the surface of the discharging member 33 with the rotation axis of the discharging member 33 as the axis, and the fixed connection positions of the number of driving plates 36 and the discharging member 33 are staggeredly distributed with the positions of a number of discharging ports 332 on the discharging member 33. During the rotation of the stirring impeller 23, the sludge can exert a force on the number of driving plates 36 after being agitated. After the number of driving plates 36 is stressed, it can drive the discharging member 33 to rotate relative to the feeding pipe 32. During the rotation of the discharging member 33, the conditioner in the cavity 331 can be thrown out through the discharging ports 332 under the centrifugal force, expanding the diffusion range when the conditioner first enters the slurry; and, during the rotation of the discharging member 33, the positions of a number of discharging ports 332 on it also change, that is, the direction in which the conditioner enters the mixing tank 11 through the discharging ports 332 also changes accordingly, making the input of the conditioner more uniform; in addition, the sludge that forms a blockage on the side of the filter screen 35 away from the cavity 331 can also be thrown out and leave the filter screen 35 under the centrifugal force, also having the effect of unclogging.

[0073] Refer to Figure 5 Furthermore, because during the rotation of the stirring impeller 23, the blade 231 will drive the sludge to move in the rotating direction and in an inclined upward direction, so the number of driving plates 36 is mainly affected by the rotation of the stirring impeller 23 near the bottom of the mixing tank 11 and drives the discharging member 33 to rotate. Preferably, the arc structure of the driving plate 36 is inclined with respect to the normal line of the position where it is fixedly connected to the discharging member 33 relative to the rotation axis of the discharging member 33, so that during the rotation of the stirring impeller 23 near the bottom of the mixing tank 11, when its blade 231 drives the sludge to move, the force exerted by the sludge on the number of driving plates 36 is more concentrated, so that the tendency of the number of driving plates 36 to drive the discharging member 33 to rotate in a certain direction under the force brought by the movement of the sludge is greater than its tendency to drive the discharging member 33 to rotate in the other direction, thereby being able to accelerate the rotation speed of the discharging member 33, and further increasing the centrifugal force on the conditioner in the cavity 331 and the sludge blocked on the filter screen 35.

[0074] Refer to Figure 2 and Figure 5, Further, the feeding device 3 further includes several clog-removing members 37. The clog-removing members 37 are located in the cavity 331. Preferably, the clog-removing members 37 are spherical structures, and the radial dimension of the clog-removing members 37 is larger than the pipe diameter of the feeding pipe 32. That is, the moving space of the clog-removing members 37 is limited to the cavity 331 only.

[0075] When the discharging member 33 is stationary, several clog-removing members 37 will be concentrated at the bottom of the cavity 331 and contact the cavity wall at the bottom of the cavity 331; during the rotation of the discharging member 33, the positions of several clog-removing members 37 in the cavity 331 will change accordingly, and under the centrifugal force, they can contact different positions of the cavity wall of the cavity 331 and one side surface of several filter meshes 35 close to the cavity 331.

[0076] When several filter meshes 35 are not blocked, during the movement of several clog-removing members 37 in the cavity 331 following the rotation of the discharging member 33, several clog-removing members 37 can stir the conditioner in the cavity 331, making the movement of the conditioner in the cavity 331 more intense, so as to help the conditioner enter the mixing tank 11 through the discharging port 332; when there is a filter mesh 35 blocked, during the movement of several clog-removing members 37 in the cavity 331 following the rotation of the discharging member 33, the clog-removing member 37 can contact one side surface of the blocked filter mesh 35 close to the cavity 331, and the clog-removing member 37 will generate an impact on it when contacting, and the impact can shake off the substances causing the blockage of the filter mesh 35, thus achieving the clog-removing effect.

[0077] The implementation principle of a sludge chemical conditioning multi-stage mixing device in an embodiment of the present application is as follows:

[0078] During the process of chemically conditioning and multi-stage mixing of sludge, several feeding devices 3 sequentially feed different conditioners into the sludge to be treated according to requirements. At the same time, the stirring device 2 stirs the sludge to accelerate the efficiency of the full mixing of the conditioner and the sludge; during the operation of the stirring device 2, it can stir the sludge and accelerate the moving speed of the sludge in the mixing tank 11. The intensified movement of the sludge can promote the feeding process of the conditioner and accelerate the feeding speed of the conditioner.

[0079] A number of filter meshes 35 on the discharge member 33 can prevent sludge from entering, thereby reducing the probability of blockage inside the feeding pipe 32 caused by sludge entering; when sludge forms a blockage on the surface of the filter mesh 35, when the stirring impeller 23 rotates and the blades 231 pass by the periphery of the discharge member 33, the movement of the slurry can impact the slurry that forms a blockage on the surface of the filter mesh 35, causing the slurry to leave the surface of the filter mesh 35; at the same time, the rotation of the stirring impeller 23 can drive the discharge member 33 to rotate. After the discharge member 33 rotates, the slurry that forms a blockage on the surface of the filter mesh 35 will leave the filter mesh 35 under the action of centrifugal force. At the same time, a number of clog-removing members 37 can move in the cavity 331 to impact the blocked filter mesh 35, shaking the sludge off the filter mesh 35, thereby greatly reducing the probability that the sludge blockage affects the process of conditioner input.

[0080] The embodiment of the present application also discloses a multi-stage mixing process for sludge chemical conditioning, which is implemented based on the above-mentioned sludge chemical conditioning multi-stage mixing equipment. The specific steps are as follows:

[0081] S1. Place the sludge into the mixing tank 11 of the sludge tank 1, and at the same time, input the liquid conditioner into the sludge through a feeding device 3 to complete the primary mixing with the sludge.

[0082] The sludge to be treated is sent into the mixing tank 11 of the sludge tank 1 through the sewage inlet device 4, and at the same time, control one of the feeding devices 3 to input a certain amount of liquid conditioner into the mixing tank 11; at this time, since the position where the sludge enters the mixing tank 11 is at a certain distance from the bottom of the mixing tank 11, after the sludge enters, the sludge moves violently in the mixing tank 11, which helps the conditioner to mix with the sludge. After the sludge is sent in and a certain amount of liquid conditioner is also input, the input liquid conditioner and the sludge complete the primary mixing.

[0083] S2. Start the stirring device 2, and at the same time, continue to input the liquid conditioner into the sludge through a feeding device 3 to achieve secondary mixing.

[0084] Control the stirring device 2 to start, stir the sludge after primary mixing in the mixing tank 11 by the rotation of the two stirring impellers 23, and at the same time, continue to input a certain amount of liquid conditioner into the mixing tank 11 through the above-mentioned feeding device 3; at this time, starting the stirring device 2 can help the input of the liquid conditioner, accelerate the input speed of the liquid conditioner and the diffusion speed of the liquid conditioner in the sludge after primary mixing, and make the input of the liquid conditioner more uniform; in addition, the sludge after primary mixing can be stirred to accelerate its mixing effect with the liquid conditioner and improve the efficiency of its full mixing with the liquid conditioner; after the liquid conditioner is input, the input liquid conditioner and the sludge complete the secondary mixing.

[0085] S3. Stop injecting the liquid conditioner and instead inject the powdered conditioner into the sludge through another feeding device 3. Complete the third-stage mixing under the agitation of the stirring device 2.

[0086] Control the above-mentioned feeding device 3 to stop working, and at the same time control another feeding device 3 to inject the powdered conditioner into the mixing tank 11. At the same time, the stirring device 2 continues to work to stir the sludge after the second-stage mixing. At this time, during the process of the powdered conditioner being injected along the feeding pipe 32, it first contacts the water in the sludge entering the discharging member 33 and the feeding pipe 32 to form a conditioner solution, and then passes through the filter screen 35 and enters the mixing tank 11 through the discharging port 332, thereby reducing the probability of the powdered conditioner forming a blockage on the side of the filter screen 35 close to the cavity 331. Moreover, starting the stirring device can also help the injection of the conditioner solution, accelerate the injection speed of the conditioner solution and the diffusion speed of the conditioner solution in the sludge after the second-stage mixing, and make the injection of the conditioner solution more uniform. In addition, the sludge after the second-stage mixing can accelerate its mixing effect with the conditioner solution and improve the efficiency of its full mixing with the conditioner solution after being agitated. After the injection of the powdered conditioner is completed and the stirring device 2 continues to work for a period of time, the injected powdered conditioner and the sludge complete the third-stage mixing.

[0087] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A multi-stage mixing device for chemical conditioning of sludge, comprising a sludge tank (1), wherein the sludge tank (1) is provided with a mixing tank (11) with an upward opening, characterized in that: The stirring device (2) further comprises a stirring device (2), the stirring device (2) comprising a driving member (21), a rotating member (22) and a plurality of stirring impellers (23), the plurality of stirring impellers (23) being arranged on the rotating member (22) and located in the mixing tank (11), the rotating member (22) being rotatably connected to the sludge tank (1) and having a vertical rotation axis, the driving member (21) being arranged on the sludge tank (1), and the driving member (21) driving the rotating member (22) to rotate; It also includes a plurality of feeding devices (3), and the plurality of feeding devices (3) are used to feed a plurality of conditioning agents into the mixing tank (11); the feeding device (3) includes a silo (31), a feeding pipe (32), a discharge piece (33) and a plurality of filter screens (35), one end of the feeding pipe (32) is connected to the silo (31), and the other end of the feeding pipe (32) is located in the mixing tank (11); the discharge piece (33) is arranged at an end of the feeding pipe (32) away from the silo (31), and the interior of the discharge piece (33) has a cavity (331) communicating with the feeding pipe (32), and the surface of the discharge piece (33) is provided with a plurality of discharge ports (332) along different directions, and the discharge ports (332) are communicated with the cavity (331); the plurality of filter screens (35) are all arranged on the discharge piece (33) and respectively cover the plurality of discharge ports (332); The discharge member (33) is located on one side of the rotating member (22), and a clearance space (24) is provided between adjacent stirring impellers (23) to provide clearance for the discharge member (33); The discharge member (33) is rotatably connected to the feeding pipe (32), and its rotation axis is perpendicular to the rotation axis of the rotating member (22). The surface of the discharge member (33) has a plurality of driving plates (36). When the stirring device (2) stirs the sludge, the plurality of driving plates (36) are driven to rotate the discharge member (33). The driving plates (36) are arranged at an angle relative to a tangent line of the driving plates (36) at their positions on the discharge member (33), and a plurality of the driving plates (36) are driven to cause the discharge member (33) to rotate in one direction.

2. A multi-stage mixing device for chemical sludge conditioning according to claim 1, characterized in that: The stirring impeller (23) comprises a plurality of blades (231), and the blades (231) are arranged obliquely relative to the rotation axis of the rotating member (22); when the driving member (21) drives the rotating member (22) to rotate, the stirring impeller (23) stirs the sludge and drives the sludge to move in a direction close to the opening of the mixing tank (11).

3. The multi-stage mixing equipment for chemical sludge conditioning according to claim 2, characterized in that: A plurality of sieve holes (2311) are formed on the blade (231), the sieve holes (2311) on the blades (231) of the same stirring impeller (23) have the same aperture, the sieve holes (2311) on the blades (231) of different stirring impellers (23) have different apertures, and the sieve holes (2311) on the blade (231) close to the opening of the mixing tank (11) have a larger aperture than the sieve holes (2311) on the blade (231) away from the opening of the mixing tank (11).

4. The multi-stage mixing equipment for chemical sludge conditioning according to claim 3, characterized in that: The stirring impeller (23) further comprises a plurality of intercepting members (232), wherein the plurality of intercepting members (232) are respectively arranged on the plurality of blades (231) and are located on the end surfaces of the blades (231) that are in contact with the sludge.

5. The multi-stage mixing equipment for chemical sludge conditioning according to claim 4, characterized in that: The intercepting member (232) has a plurality of protrusions (2321), and an intercepting space (2322) is formed between adjacent protrusions (2321) on the same intercepting member (232).

6. The multi-stage mixing equipment for chemical sludge conditioning according to claim 2, characterized in that: The blades (231) on adjacent stirring impellers (23) are staggered and distributed along the rotation axis of the rotating member (22).

7. The multi-stage mixing equipment for chemical sludge conditioning according to claim 1, characterized in that: The feeding device (3) further comprises a plurality of clearing members (37), wherein the clearing members (37) are located in the cavity (331); when the discharging member (33) rotates, the clearing members (37) move in the cavity (331).

8. A multi-stage mixing process for chemical conditioning of sludge, characterized in that: The sludge chemical conditioning multi-stage mixing device according to any one of claims 1 to 7 is implemented by the following specific steps: The sludge is placed in the mixing tank (11) of the sludge tank (1), and at the same time, a liquid conditioner is added into the sludge through a feeding device (3) to complete primary mixing with the sludge; The stirring device (2) is started, and at the same time, the liquid conditioner is continuously added to the sludge through the feeding device (3) to achieve secondary mixing; Stop adding the liquid conditioner, and instead add the powdered conditioner into the sludge through another feeding device (3), and complete the three-stage mixing under the stirring action of the stirring device (2).

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