Layered clarification fluidized bed

Abstract

The utility model discloses a layered clarification fluidized bed which comprises a vertical closed tank body, an inner cylinder fixedly connected in the tank body, a water outlet pipe fixedly connected to the top of the tank body in a penetrating manner, and a water inlet pipe fixedly connected to the part, close to the bottom, of the tank body in a penetrating manner, the bottom of the inner cylinder is closed, the water inlet pipe is communicated with the bottom of the inner cylinder, the top of the inner cylinder is open, the top end of the inner cylinder is fixedly connected with a reducing expansion pipe, and the large-diameter end of the expansion pipe is upward; the middle cylinder is arranged on the outer side of the inner cylinder and communicated with the middle of the inner cylinder, and sludge flows back to the middle of the inner cylinder; a cavity gap is formed among the tank body, the middle cylinder and the inner cylinder and serves as a sludge settling channel, sludge falls into a sludge collecting area at the bottom of the tank body, and the sludge collecting area is communicated with the outside of the tank body to discharge sludge. A new density layering, clarifying and separating mechanism is provided and applied in a coagulation and clarification treatment technology, the clarification and separation level is improved by utilizing the blocking characteristic of layering fluid, the effluent quality is improved, a new sludge backflow path is applied, the coagulation quality is improved, and formation of density layering fluid is promoted.

Description

Technical Field

[0001] The utility model relates to the technical field of water treatment equipment, in particular to a layered clarification fluidized bed. Background Technique

[0002] In many regions of China, industrial water is in short supply. Coupled with the constraints of environmental protection policies, the demand for industrial water clarification treatment is more extensive, and more requirements are put forward for the quality of the effluent. In some production fields, the equipment is required to be simple and efficient. The current water treatment coagulation clarification technology has been difficult to fully meet these requirements. For a long time, the widely used water clarification methods in China are hydraulic circulation clarifiers, accelerated clarifiers, suspended clarifiers, pulse clarifiers and other facilities. The common disadvantages are low flow velocity and large floor area of the equipment. The representative technology abroad is the French DensaDeg high-density clarifier, and the surface load of the separation zone reaches 20-50 m / h. The disadvantages of these devices are relatively large floor area and complex auxiliary equipment. In the past, the upper part of the coagulation zone of the integrated clarification equipment was all straight cylindrical. Many sludge particles could not achieve rapid deceleration in the separation zone, resulting in a higher sludge layer in the clarification separation zone, and fine particles were easily carried into the effluent. At present, there is a lack of effective improvement measures. In the past, the integrated clarification equipment generally formed a low-pressure zone through the change of water flow velocity to realize the return of high-concentration sludge in the separation zone to the lower part of the coagulation zone. However, it is very difficult to achieve stable sludge return for the complex flow pattern during the coagulation process, and the sludge return of the clarification equipment is a very crucial process to improve the coagulation speed and quality. Content of the Utility Model

[0003] The technical problem to be solved by the utility model is to provide a layered clarification fluidized bed, which expands the capacity and realizes stable sludge return at the end of the fluidized bed coagulation process, constructs a density stratified fluid structure of sludge and clear water, and uses the blocking characteristics of the density stratified fluid to solve the problem of high carry-over of fine particles in the effluent of the clarification equipment.

[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0005] A layered clarification fluidized bed includes a vertical closed tank body, an inner cylinder fixedly connected inside the tank body, a water outlet pipe fixedly connected through the top of the tank body, and a water inlet pipe fixedly connected through the tank wall of the tank body. The water inlet pipe enters from the bottom of the inner cylinder. The inner cylinder is located in the middle of the tank body. The bottom of the inner cylinder is closed and the top is open. A flared expansion pipe is fixedly connected to the top end of the inner cylinder, with the large-diameter end of the expansion pipe facing upward. There is a gap between the tank body and the inner cylinder. The water inlet pipe is communicated with the inner cylinder at the bottom. The bottom of the tank body is a sludge collection area, and the sludge collection area is communicated with the outside of the tank body.

[0006] Furthermore, a stirrer is fixedly arranged on the tank body, and the impeller of the stirrer is located inside the inner cylinder.

[0007] Furthermore, an intermediate cylinder with an open top is provided between the inner cylinder and the tank body. The upper part of the inner cylinder and the expansion pipe are both located inside the intermediate cylinder. The inner cylinder is fixedly connected to the intermediate cylinder through penetration. The top of the intermediate cylinder is higher than the expansion pipe, and the bottom of the intermediate cylinder communicates with the middle part of the inner cylinder.

[0008] Furthermore, a stirrer is fixedly arranged on the tank body, and the stirring shaft of the stirrer is arranged vertically inside the inner cylinder.

[0009] Furthermore, a sludge return pipe is fixedly arranged inside the inner cylinder. The sludge return pipe communicates the bottom of the intermediate cylinder with the inside of the inner cylinder. The sludge return pipe divides the inner cylinder into two parts, namely the lower first reaction zone and the upper second reaction zone. The stirring intensity of the stirrer in the first reaction zone is greater than that in the second reaction zone.

[0010] Furthermore, the impellers on the stirring shaft are several distributed along its axial direction, and the impeller distribution in the first reaction zone is denser than that in the second reaction zone.

[0011] Furthermore, the bottom of the inner cylinder is fixedly connected with a head. The inside of the head communicates with the inside of the inner cylinder. The bottom of the head is fixedly connected with a vertical pipe through penetration, and the vertical pipe is fixedly connected with the water inlet pipe.

[0012] The positive effects of the present utility model are as follows:

[0013] By constructing a dissipative structure, the coagulation time is shortened and the coagulation quality is improved. After industrial water is added with a coagulant and a coagulant aid and enters the inner cylinder, it sequentially passes through the first reaction zone and the second reaction zone from bottom to top. By controlling the higher stirring intensity in the first reaction zone, the colloid particle aggregates are made dense and maintained within a smaller particle size, and a larger number of particles are maintained, avoiding the formation of large vanadium flowers with lower density; in the lower part of the second reaction zone, sludge reflux occurs, and the sludge volume increases geometrically. The stirring intensity in the second reaction zone gradually decreases. When the colloid entropy value reaches the upper limit at the lower part of the expansion pipe, the mechanical stirring is removed to form a dissipative structure. The coagulated particles use the large entropy fluctuation as the driving force to realize the rapid and relatively regular coagulation and growth of small coagulated aggregates, forming large particles with a larger density. Effectively shortening the coagulation time is a bottleneck that the integrated equipment needs to break through.

[0014] The present utility model proposes and systematically applies the density stratification clarification and separation mechanism to improve the quality of clarification and separation. With the technical goal of forming a density-stratified fluid of sludge and water, further expansion is achieved by designing an expansion pipe and a middle cylinder of a certain height to construct fluid conditions that conform to the overall fall of the sludge. After the sludge accumulates to form a fluidized layer with a higher density, a density-stratified fluid with a relatively clear stratification interface will be formed, and the height of the stratification interface can be less than a few centimeters. The density-stratified fluid has the characteristic of blocking small particles. The tiny particles on the density stratification interface tend to return to the high-density layer under the action of internal waves, and there is a greater probability that the tiny particles will re-adsorb to the large particles. In the stratification clarification technology, a large number of active particles are maintained in the expansion pipe, and the van der Waals energy is relatively high. A large number of tiny particles are more likely to be adsorbed in this area, reducing the number of tiny particles entering the separation area. As the concentration of sludge particles increases, the density stratification interface will rise vertically. After exceeding the upper edge of the middle cylinder, the sludge will overflow into the sedimentation area and then settle to the lower sludge collection area of the tank body under the action of gravity, and the sludge forms a dynamic balance. In the past, the clarification and separation technologies mainly included reducing the flow rate in the clarification and separation area by following the gravity separation technology route, which necessarily required a large floor area for the equipment; there was also the collision adsorption technology route that added inclined plates or inclined tubes in the clarification and separation area, which could generally capture about 50% of the fine particles; there was also the clarification and separation that combined the above two technical measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 are schematic structural diagrams of Embodiment 1 and Embodiment 2;

[0016] Figure 2 is a schematic structural diagram of Embodiment 3;

[0017] In the figure:

[0018] 1, sludge discharge area; 2, tank body; 3, vertical pipe; 4, head; 5, inner cylinder; 6, expansion pipe; 7, water outlet pipe; 8, middle cylinder; 9, sludge return pipe; 10, stirrer; 11, water inlet pipe; 12, sludge collection area; 13, first reaction area; 14, second reaction area; 15, clear water area; 16, separation area; 17, sedimentation area; 18, return area. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] Embodiment 1

[0020] As Figure 1As shown in the figure, a layered clarifying fluidized bed includes a vertical, closed, circular tank body 2, an inner cylinder 5 fixedly connected inside the tank body 2, a water outlet pipe 7 fixedly connected through and at the top of the tank body 2, and a water inlet pipe 11 fixedly connected through and at the side wall of the tank body 2 near the bottom. The tank body 2 and the inner cylinder 5 are coaxial, the inner cylinder 5 is located in the middle of the tank body 2, a semi-elliptical head 4 is fixedly arranged at the bottom of the inner cylinder 5, the head 4 seals the bottom of the inner cylinder 5, and a vertical pipe 3 is fixedly connected through the center position at the bottom of the head 4.

[0021] The top of the inner cylinder 5 is open, there is a gap between the tank body 2 and the inner cylinder 5, the bottom of the vertical pipe 3 is sealed and the top is open. The water inlet pipe 11 is perpendicularly and fixedly connected to the side wall of the vertical pipe 3, and the water inlet pipe 11 communicates with the bottom of the vertical pipe 3. The bottom of the tank body 2 is a sludge collection area 12, the bottom of the tank body 2 is funnel-shaped, the center of the bottom of the tank body 2 is a sludge discharge area 1, and the sludge discharge area 1 communicates with the outside of the tank body 2. A flared expansion pipe 6 is fixedly connected to the top end of the inner cylinder 5, and the large-diameter end of the expansion pipe 6 faces upward.

[0022] Near the top inside the tank body 2 is a clear water area 15, the part near the top of the expansion pipe 6 inside the tank body 2 is a separation area 16, and the area between the expansion pipe 6 and the tank body 2 and between the inner cylinder 5 and the tank body 2 is a sedimentation area 17.

[0023] The working process of the present utility model is as follows:

[0024] After the sewage is added with a coagulant and mixed through a static pipeline mixer, a flocculant is added, enters the head 4 upward through the water inlet pipe 11 and the vertical pipe 3, and then flows upward inside the inner cylinder 5. The impurities in the sewage form aggregates under the action of the coagulant and the flocculant, and during the upward flow process, the aggregates gradually grow to form sludge, and then enter the separation area through the expansion pipe 6. Since the expansion pipe 6 is larger at the top and smaller at the bottom, the flow velocity of the water gradually decreases when flowing upward inside it. When the flow velocity of the water is less than the critical sedimentation velocity of the sludge (that is, the flow velocity is not sufficient to make the aggregates flow with it), these sludges will accumulate in the separation area 16. When the accumulation height exceeds the upper edge of the middle cylinder 8, they will break away from the water flow and enter the sedimentation area 17, and then fall to the sludge collection area 12 for storage. A sludge level gauge is provided on the side wall of the tank body 2 to detect the sludge stock in the sludge collection area 12. When it reaches the set amount, the valve connecting the bottom of the tank body 2 and the sludge discharge area 1 is opened to discharge the sludge. The purified clear water continues to flow upward from the separation area 16 into the clear water area 15, and then is discharged through the water outlet pipe 7.

[0025] Since the utility model adopts a vertical structure, the flow direction of the sewage in the inner cylinder 5 is vertical, and aggregates are formed and gradually grow during the flow. Then, after the aggregates are separated, they fall downward and are discharged from the sludge discharge area 1, while the clear water flows upward and is discharged from the water outlet pipe 7, realizing the purification of the sewage. Therefore, there is no need to use a variety of equipment or facilities to treat the sewage, because mechanical stirring, coagulation, clarification, separation, and sludge storage are carried out in the same tank body, thus greatly reducing the floor area of the equipment.

[0026] Embodiment 2

[0027] The difference between this embodiment and Embodiment 1 is as follows:

[0028] A stirrer 10 is fixedly arranged at the bottom of the tank body 2. The stirring shaft of the stirrer 10 vertically penetrates the bottom of the tank body 1 where the sludge discharge area 1 is located and the bottom of the vertical pipe 3. The impeller of the stirrer 10 is located inside the inner cylinder 5. The bottom of the tank body 1 and the vertical pipe 3 are both in sealed cooperation with the stirring shaft.

[0029] Driven by the stirrer 10, the water flow inside the inner cylinder 5 rises in a spiral shape, so that the coagulant and the flocculant can fully react with the sewage, improving the reaction efficiency and further improving the sewage purification efficiency.

[0030] Embodiment 3

[0031] As Figure 2 shown, the difference between this embodiment and Embodiment 2 is as follows:

[0032] An intermediate cylinder 8 with an open top is provided between the inner cylinder 5 and the tank body 2. The upper part of the inner cylinder 5 and the expansion pipe 6 are both located inside the intermediate cylinder 8. The inner cylinder 5 is fixedly connected to the intermediate cylinder 8 through penetration. The top of the intermediate cylinder 8 is higher than the expansion pipe 6. The bottom of the intermediate cylinder 8 is communicated with the middle part of the inner cylinder 5. The separation area 16 is located between the top end of the intermediate cylinder 8 and the top end of the expansion pipe 6. The sedimentation area 17 is located between the intermediate cylinder 8 and the tank body 2. The area between the expansion pipe 6 and the intermediate cylinder 8 and the area between the inner cylinder 5 and the intermediate cylinder 8 are the reflux areas 18.

[0033] Four sludge return pipes 9 are fixedly arranged inside the inner cylinder 5. The sludge return pipes 9 are arranged along the circumferential direction of the inner cylinder 5. The sludge return pipes 9 communicate the bottom of the reflux area 18 and the inside of the inner cylinder 5 near the middle part. The sludge return pipes 9 divide the inner cylinder 5 into two parts, namely the lower first reaction area 13 and the upper second reaction area 14. The stirring intensity of the stirrer 10 in the first reaction area 13 is greater than that in the second reaction area 14.

[0034] The impellers on the stirring shaft are five distributed along its axial direction. The impeller distribution in the first reaction area 13 is denser than that in the second reaction area 14. There are three impellers in the first reaction area 13 and two impellers in the second reaction area 14.

[0035] In this embodiment, the working process of the utility model is as follows:

[0036] 1. After adding a coagulant to the sewage and mixing it through a static pipeline mixer, and then adding a flocculant aid, it enters the head 4 upward through the water inlet pipe 11 and the vertical pipe 3, and then enters the first reaction zone 13 in the inner cylinder 5.

[0037] 2. In the first reaction zone 13, the impeller of the stirrer 10 has a large number of blades, and the stirring intensity is high, the shear force is large, and the velocity gradient is high. In the first reaction zone 13, high-energy aggregates with high density and small particle size are formed.

[0038] 3. The aggregates flow upward with the water flow into the second reaction zone 14. In the second reaction zone 14, the stirring intensity of the stirrer 10 becomes lower, the shear force weakens, and the aggregates in the sewage begin to grow. Then these grown aggregates continue to flow upward with the water flow.

[0039] 4. After the grown aggregates enter the expansion pipe 6, they are no longer stirred by the stirrer 10. The flow velocity of the water flow decreases in the expansion pipe 6. The particle concentration of the aggregates is high in the expansion pipe 6, and there is also efficient mass transfer of particle fluidization. The two conditions of the van der Waals force accumulated in the first reaction zone 13 and the increase in particle concentration are coupled together. Entropy fluctuations occur in the expansion pipe 6, and the accumulated van der Waals force is converted into numerous small particles quickly adsorbing into denser sludge. The large particle sludge falls back to form a fluidized bed, and the high-density fluidized bed formed by the large particle sludge forms a density-stratified fluid in the separation zone 16. The clarified water separated from the upper part of the separation zone 16 flows upward into the clear water zone 15, and then is discharged upward through the water outlet pipe.

[0040] 5. When the impeller of the stirrer 10 rotates, a low-pressure area is formed in the center of the inner cylinder 5. The reflux zone 18 and the sludge reflux pipe 9 form a sludge reflux channel. The sludge with a higher concentration at the lower part of the separation zone 16 flows back to the lower part of the second reaction zone 14 through the reflux channel, and then continues to grow in the second reaction zone 14.

[0041] 6. When the content of aggregate particles in the separation zone 16 increases, the top of the separation zone 16 moves upward. When the height of the separation zone 16 is higher than the middle cylinder, the sludge will overflow into the sedimentation zone 17. The centrifugal force formed by the mechanical stirring of the stirrer 10 will also push the aggregates into the sedimentation zone 17. Then the sludge settles to the sludge collection area 12 for storage under the action of gravity. A sludge level gauge is provided on the side wall of the tank body 2 to detect the sludge inventory in the sludge collection area 12. When the set amount is reached, the valve connecting the bottom of the tank body 2 to the sludge discharge area 1 is opened to discharge the sludge. The purified clear water continues to flow upward from the separation zone 16 into the clear water zone 15, and then is discharged through the water outlet pipe 7.

[0042] The coagulation technology adopted in current water treatment is to set the sludge return at the initial stage of the coagulation process. The dissipative structure is relatively weak, which is not conducive to accelerating the adsorption of fine particles, cannot effectively compress the coagulation time, and will bring contradictions in terms of equipment manufacturing, installation, cost, and effluent quality. In the present utility model, the mechanical stirring intensity of the stirrer 10 changes from strong to weak during the upward flow of water, so that the number of colloidal particles in the incoming water is large and the particle density is high. The sludge returns to the second reaction zone, accumulates particles in the expansion tube 6, can geometrically increase the number of particles, create fluctuations in the entropy of the colloidal particles, form a strong dissipative structure, and realize rapid coagulation of the colloidal particles in the expansion tube 6, and can compress the coagulation time within a certain height by several times. Therefore, the present utility model proposes a new layered fluid clarification and separation mechanism in the coagulation and clarification treatment technology to solve the problem that it is difficult to actively and effectively inhibit fine particles from entering the clear water area in existing water treatment equipment, and constructs a new flow state system and coagulation system for the layered fluid mechanism in the integrated clarification equipment.

[0043] The description of the above embodiments is relatively detailed and specific, expressing the preferred embodiments of the present utility model, and is only used to illustrate the technical ideas and features of the present utility model. Its purpose is to enable those skilled in the art to understand the content of the present utility model and implement it accordingly, but it is not limited to the present utility model only. The patent scope of the present utility model cannot be limited only by this embodiment. That is, any equivalent changes or modifications made in accordance with the spirit disclosed by the present utility model, for researchers or technicians in the field, within the structure of the present utility model, local improvements within the system and changes and transformations between subsystems are still within the patent scope of the present utility model.

Claims

1. A layered clarification fluidized bed, characterized in that: The invention comprises a vertical closed tank body (2), an inner cylinder (5) fixedly connected inside the tank body (2), a water outlet pipe (7) penetrating and fixedly connected to the top of the tank body (2), and a water inlet pipe (11) penetrating and fixedly connected to the tank wall of the tank body (2), wherein the water inlet pipe (11) enters from the bottom of the inner cylinder (5); the inner cylinder (5) is located in the middle of the tank body (2), the bottom of the inner cylinder (5) is closed and the top is open, a trumpet-shaped expansion pipe (6) is fixedly connected to the top of the inner cylinder (5), the large-diameter end of the expansion pipe (6) faces upward, a gap is provided between the tank body (2) and the inner cylinder (5), the water inlet pipe (11) is connected to the inner cylinder (5) at the bottom, the bottom of the tank body (2) is a mud collection area (12), and the mud collection area (12) is connected to the outside of the tank body (2).

2. A layered clarification fluidized bed according to claim 1, characterized in that: The tank body (2) is fixedly provided with an agitator (10), and the impeller of the agitator (10) is located inside the inner cylinder (5).

3. A layered clarification fluidized bed according to claim 1, characterized in that: An intermediate cylinder (8) with an opening at the top is provided between the inner cylinder (5) and the tank body (2); the upper part of the inner cylinder (5) and the expansion tube (6) are both located inside the intermediate cylinder (8); the inner cylinder (5) and the intermediate cylinder (8) are connected through and fixed to each other; the top of the intermediate cylinder (8) is higher than the expansion tube (6); and the bottom of the intermediate cylinder (8) is connected to the middle of the inner cylinder (5).

4. A layered clarification fluidized bed according to claim 3, characterized in that: The tank body (2) is fixedly provided with an agitator (10), and the agitator shaft of the agitator (10) is vertically arranged inside the inner cylinder (5).

5. A layered clarification fluidized bed according to claim 4, characterized in that: A sludge return pipe (9) is fixedly arranged in the inner cylinder (5), and the sludge return pipe (9) connects the bottom of the intermediate cylinder (8) and the interior of the inner cylinder (5). The sludge return pipe (9) divides the inner cylinder (5) into two parts, namely a first reaction zone (13) at the bottom and a second reaction zone (14) at the top. The stirring intensity of the agitator (10) in the first reaction zone (13) is greater than that in the second reaction zone (14).

6. A layered clarification fluidized bed according to claim 5, characterized in that: The impellers on the stirring shaft are multiple and distributed along the axial direction thereof, and the impellers in the first reaction zone (13) are more densely distributed than the impellers in the second reaction zone (14).

7. The layered clarification fluidized bed according to claim 1, characterized in that: The bottom of the inner tube (5) is fixedly connected to a sealing head (4), the interior of the sealing head (4) is in communication with the interior of the inner tube (5), a vertical pipe (3) is passed through and fixedly connected to the bottom of the sealing head (4), and the vertical pipe (3) is fixedly connected to a water inlet pipe (11).

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