Super-consolidation efficient thickener

Abstract

The invention discloses a super-efficient thickener with overflow particle filtering and trapping and underflow super-consolidation technologies. The super-efficient thickener comprises a tank body, an overflow weir and a central feeding well which are arranged at the top of the tank body, an overflow particle filtering and trapping assembly arranged between the feeding well and the tank wall, and an underflow super-consolidation assembly and a discharge pipeline which are arranged at the lower part of the tank body, the underflow over-consolidation assembly comprises a drainage channel and a mud bed pressurization system, the pressurization system enables a bottom mud bed to generate ultra-static pore water pressure, then consolidated water is rapidly drained away through the special drainage channel, and the target underflow concentration is obtained. Compared with the existing thickener technology, the thickener has the advantages that the clarity of the overflow water and the concentration of the underflow are effectively controlled, the unit area treatment capacity can be greatly improved, the boundary dimension and the cost of the thickener are reduced, the concentration of the underflow can be flexibly adjusted, and the thickener can be suitable for more application scenes.

Description

Technical Field

[0001] This invention relates to the field of solid-liquid separation and thickening technology, specifically to an ultra-consolidated high-efficiency thickener. Background Technology

[0002] A thickener is a solid-liquid separation device based on gravity sedimentation, widely used in mining, metallurgy, chemical, and environmental protection industries. Theoretical research on thickeners has a history of over a century, establishing various sedimentation theories and calculation methods for its core indicator, "processing capacity per unit area." It is generally believed that the processing capacity per unit area of ​​a thickener depends on the particle settling velocity. In practice, high-efficiency thickening technologies that use flocculants to increase the size of particle flocs, thereby improving their gravity settling velocity, are widely used. Furthermore, the existence of an optimal flocculation concentration for each slurry is now an industry consensus, leading to various feeding technologies with feed dilution functions. In addition, underwater feeding and tangential feeding methods using feed wells, based on the concept of uniform mixing of slurry and flocculant, are also widely applied.

[0003] Currently, mainstream high-efficiency thickeners generally employ center drive and include major components such as the tank, feed well, and rake frame. The tank consists of a cylindrical upper tank, a conical lower tank, and supporting structures. The slurry to be treated enters the feed well and mixes with flocculant, then flows out of the feed well to begin solid-liquid separation. After the thickener enters steady-state operation, it can be divided into an overflow clarification zone, a particle settling zone, and a mud bed compression zone from top to bottom, according to the material morphology. The rake frame is located in the compression zone below the mud surface. The drive mechanism rotates the rake frame and bottom scraper at a slow speed, pushing the mud layer in the compression zone towards the underflow discharge port, and also agitating the slurry to prevent caking and shearing dewatering. As a major mechanical component of the thickener, the rake frame bears enormous torque resistance from the mud bed, especially in the case of large-diameter tanks and high-concentration underflow, thus facing the risk of "rake crushing."

[0004] For deep cone thickeners, to achieve a high underflow concentration, the height of the mud bed must be increased by increasing the height of the upper tank sidewalls and the cone angle of the lower tank, thereby increasing the bottom mud bed pressure. This leads to a sharp increase in the resistance and energy consumption of the rake frame. To accelerate the increase in underflow concentration, the deep cone thickener's rake frame is equipped with a special water guide rod to shear and dewater the particle flocs. However, due to the lack of an effective drainage channel, the underflow thickening process is very slow, often requiring more than 8 hours, even though the flocculation and sedimentation process of the particles is usually completed within half an hour.

[0005] Furthermore, regarding the selection of thickeners, a key point is to maintain the clarity of the overflow water and avoid "turbidity." The settling area of ​​the thickener must be large enough so that the rising velocity of the overflow water is less than the gravity settling velocity that limits the fine particles. With advancements in modern flocculant development and feed well design, over 80% of particles can be effectively flocculated and settled. For the remaining less than 20% of ineffectively flocculated ultrafine particles, according to Stokes' theory, their gravity settling velocity is proportional to the square of the particle radius, meaning it is extremely small. This necessitates increasing the area several times over to meet the aforementioned principle, leading to a sharp increase in construction costs, land area, operating energy consumption, and the risk of scraping. From a value engineering perspective, significantly increasing the thickener area for the sake of a small percentage of fine particles is highly uneconomical. Summary of the Invention

[0006] In response to the above situation, the present invention provides an ultra-high efficiency thickener with overflow particle filtration and capture and underflow super-consolidation components. By intercepting and capturing fine particles in the overflow and controlling the drainage and consolidation of the underflow concentration, the thickener's unit area processing capacity is significantly improved.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows, including: a pool body, an overflow weir and a central feed well disposed at the top of the pool body, a filter and collection assembly for overflow particles disposed between the feed well and the pool wall, an electromechanical assembly, an underflow super-consolidation assembly and an underflow discharge pipe.

[0008] Furthermore, the pool body is divided into an upper straight section, a conical transition section, and a bottom straight section from top to bottom. The size of the bottom straight section is smaller than that of the upper straight section. In the design without a rake, in order for the slurry to automatically converge and flow downward under its own weight, the cone angle is preferably not less than 30°.

[0009] Furthermore, the overflow particle filtration and collection assembly includes a filter membrane and a particle collection device; the upper end of the assembly is enclosed by the outer wall of the feed well, and the lower end is close to or submerged below the mud surface, intercepting and collecting ultrafine particles that have not been effectively flocculated; the collected fine particles are returned to the feed well through the pipeline for flocculation and sedimentation, or directly introduced into the depth of the mud bed for compression and consolidation.

[0010] Furthermore, the electromechanical components include a power and control system, and one or more of the following: a central spindle, a rake frame, a scraper, a mud bed guide cone, and a mixing blades. The mixing blades are distributed on the central spindle, with the upper end located in the mud bed conical transition zone and the lower end in the underflow discharge zone. The upper blades uniformly mix the slurry and assist in feeding the super-consolidation zone, while the lower blades uniformly mix the underflow and prevent caking. In a design without a rake frame, the conical transition section is equipped with a mud bed guide cone and optional sidewall anti-caking flow-aiding nozzles. The central guide cone is fixed to the central shaft, with its large end facing downwards, guiding the slurry to flow uniformly downwards and preventing the slurry from "short-circuiting" along the central shaft. The flow-aiding nozzles are evenly distributed on the sidewalls of the conical tank, with one end connected to a high-pressure air duct or water pipe. When the requirement for the underflow concentration increase rate is not high, a non-powered consolidation method can also be adopted.

[0011] Furthermore, the underflow overconsolidation component includes drainage channels and a mud bed pressurization system. One end of the drainage channel is located in the underflow consolidation zone, and the other end is above the mud surface, or it can directly pass through the side wall of the thickener to discharge the consolidation water; multiple drainage channels form a drainage network, and preferably, the drainage channels are plastic drainage board columns or bagged sand well columns.

[0012] Furthermore, the mud bed pressurization system acts on the slurry in the bottom straight section, and the pressurization method includes one or more of ballast, vacuum negative pressure, vibration or tamping; preferably, the ballast is achieved by hydraulic means. When the pressurization method is ballast or overall vacuum negative pressure, it also includes a liftable isolation plug located at the top of the bottom straight section, which serves as the actuating component of the ballast or the sealing component for evacuating the bottom slurry as a whole.

[0013] The mud bed pressurization system is powered by electromechanical components. The actuating parts are located in the mud bed or on the bridge. When located in the mud bed, an isolation cover separates it from the slurry. The intensity and duration of pressurization are determined according to the target underflow concentration and the set consolidation time.

[0014] The ultra-consolidated thickener provided by this invention is divided into an overflow clarification zone, a particle settling zone, a mud bed compression zone, and an underflow ultra-consolidation zone from top to bottom. Feeding and underflow discharge from the feed well are continuous, while feeding and pressurized consolidation alternate in the underflow consolidation zone.

[0015] The beneficial effects of this solution using the above method are as follows: By setting up a dedicated drainage channel and a controllable sludge bed pressurization system, the target underflow concentration is obtained more quickly; the advantages of modern flocculation technology are fully utilized and the clarity of the overflow is ensured, thereby significantly improving the core indicator of the thickener's unit area processing capacity; this reduces the area of ​​the thickener and the height of the deep cone sludge bed, effectively reducing the energy consumption of the rake frame mechanical system, and even eliminating the rake frame altogether. In summary, this solution can reduce the cost, footprint, and operational risks of the thickener, and can expand its underflow concentration and application scenarios. Attached Figure Description

[0016] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention, making its features, objects, and advantages more apparent. The illustrative embodiments of the invention, along with their descriptions, are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0017] Figure 1 This is a schematic diagram of the structure of Embodiment 1 proposed in this invention.

[0018] Figure 2 This is a schematic diagram of the structure of Embodiment 2 proposed in this invention.

[0019] Figure 3 This is a schematic diagram of the structure of Embodiment 3 proposed in this invention.

[0020] Figure 4 This is a schematic cross-sectional view of the underflow consolidation zone in Embodiment 3 of the present invention.

[0021] Figure 5 This is a schematic diagram of the structure of Embodiment 4 of the present invention.

[0022] Wherein: 11-Upper straight cylindrical section of the pool body; 12-Conical transition section; 13-Bottom straight cylindrical section; 21-Feeding well; 22-Overflow weir; 23-Overflow particle filter and collection assembly; 31-Drainage channel; 311-Radial drainage channel; 312-Circumferential drainage channel; 32-Ballast jack; 33-Liftable isolation plug; 34-Underflow discharge pipeline; 35-Vacuum pipeline; 36-Side wall drainage interlayer; 41-Power and control system; 42-Central main shaft; 43-Rake frame and scraper; 44-Water guide rod; 45-Bridge frame; 46-Agitator blades; 47-Sludge bed guide cone. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be described below with reference to the accompanying drawings. It should also be noted that the accompanying drawings only show structures and processing steps closely related to the present invention, while other details not closely related to the present invention are omitted.

[0024] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0025] Example 1

[0026] like Figure 1As shown, this embodiment provides an ultra-consolidated high-efficiency thickener with a rake frame, comprising: a pool body, an overflow weir and a central feed well disposed at the top of the pool body, a filter and collection assembly for overflow particles disposed between the feed well and the pool wall, an electromechanical assembly, an underflow ultra-consolidation assembly, and an underflow discharge pipe. The pool body is divided into an upper straight section, a conical transition section, and a bottom straight section from top to bottom, with the bottom straight section being smaller than the upper straight section.

[0027] The overflow particle filtration and collection assembly includes a filter membrane and a particle collection device. The upper end of the assembly is enclosed by the outer wall of the feed well, and the lower end is close to or submerged below the mud surface, intercepting and collecting ultrafine particles that cannot be effectively flocculated. The collected fine particles are returned to the feed well through pipelines for flocculation and sedimentation, or directly introduced into the depths of the mud bed for compression and consolidation.

[0028] The electromechanical components include a power and control system, as well as a central spindle, rake frame, scraper, and agitator blades. The power system is located on a bridge frame, while the rake frame, scraper, and agitator blades are all fixed to the central spindle. The rake frame rotates slowly with the spindle, driving the mud towards the bottom consolidation zone. A water guide rod is also provided on the rake frame for initial dewatering of the mud; the agitator blades, located in the bottom consolidation zone, mix the mud evenly in this area and prevent caking.

[0029] The underflow overconsolidation assembly includes vertical drainage channels and a mud bed pressurization system. One end of the drainage channel is located in the underflow consolidation zone, and the other end is above the mud surface. Multiple drainage channels are distributed in a ring to form a drainage network. The drainage channels are plastic drainage columns, encased in limiting steel pipes, and fixed to the central main shaft by stirring blades and a rake frame.

[0030] In this embodiment, the pressurization method of the mud bed pressurization system is ballast, driven by the top power system. The hydraulic jack is located at the top of the bottom straight section, pushing the liftable isolation plug up and down to perform feeding and pressurizing consolidation operations in the consolidation zone. The underwater pressurization component is isolated from the mud by a retractable waterproof cover; the isolation plug has an opening at the position of the vertical drainage channel, and the excess pore water pressure generated by the ballast flows upward through the drainage channel and flows away through the overflow weir, while the high-concentration underflow is continuously discharged through the underflow discharge pipeline.

[0031] Example 2

[0032] like Figure 2As shown, this embodiment provides a rake-free ultra-consolidation high-efficiency thickener. Compared with embodiment one, the difference in this embodiment is that the rake is eliminated, and the slurry can automatically converge and flow downward under its own weight. The cone angle of the transition zone is 45°. The conical transition section is provided with a mud bed guide cone. The central guide cone is fixed on the central shaft, with the large end opening downward, guiding the slurry to flow downward evenly and preventing the slurry from "short-circuiting" along the central shaft when feeding into the consolidation zone. The pressurization method of the mud bed pressurization system is hydraulic ballast combined with vacuum negative pressure. The mud bed guide cone has openings at the positions of the vertical drainage channel and the vacuum pipe.

[0033] Example 3

[0034] like Figure 3 , 4 As shown, this embodiment provides a rake-free ultra-consolidation high-efficiency thickener. Compared with embodiment two, the difference in this embodiment is that a drainage jacket is provided on the outside of the straight cylindrical area at the bottom of the tank. The drainage pipe does not extend upwards but directly passes through the side wall of the thickener to discharge the consolidation water into the jacket, and then flows into the overflow tank through a special channel. The liftable isolation plug and mud bed guide cone do not have drainage pipe openings.

[0035] Example 4

[0036] like Figure 5 As shown, this embodiment provides a non-powered ultra-consolidated high-efficiency thickener. Compared with embodiment three, the difference in this embodiment is that the central shaft does not rotate, the drainage channel is set vertically, and the mud bed pressurization system only performs local vacuuming intervention on the drainage channel.

[0037] The ultra-consolidated high-efficiency thickener provided in the above embodiments has high processing capacity per unit area, fast underflow concentration acquisition speed, and wide concentration range, making it suitable for various application scenarios.

[0038] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A super-consolidated high-efficiency thickener, characterized in that, include: The pool body includes an overflow weir and a central feed well at the top of the pool body, a filter and capture assembly for overflow particles between the feed well and the pool wall, an electromechanical assembly, an underflow super-consolidation assembly, and an underflow discharge pipe.

2. The ultra-consolidated high-efficiency thickener according to claim 1, characterized in that, The pool is divided into an upper straight section, a conical transition section, and a bottom straight section from top to bottom. The bottom straight section is smaller than the upper straight section.

3. The ultra-consolidated high-efficiency thickener according to claim 1, characterized in that, The overflow particle filtration and collection assembly includes a filter membrane and a particle collection device; the upper end of the assembly is enclosed by the outer wall of the feed well, and the lower end is close to or submerged below the mud surface, intercepting and collecting ultrafine particles that cannot be effectively flocculated.

4. The ultra-consolidated high-efficiency thickener according to claim 1, characterized in that, The electromechanical components include a power and control system, as well as one or more of the following: a central spindle, a rake frame, a scraper, a mud bed guide cone, and a mixing blades.

5. The ultra-consolidated high-efficiency thickener according to claim 1, characterized in that, The underflow overconsolidation component includes drainage channels and a mud bed pressurization system.

6. The ultra-consolidated high-efficiency thickener according to claim 5, characterized in that, One end of the drainage channel is located in the bottom flow consolidation zone, and the other end is located above the mud surface, or directly through the side wall of the thickener; multiple drainage channels form a drainage network, preferably, the drainage channels are plastic drainage board columns or bagged sand well columns.

7. The ultra-consolidated high-efficiency thickener according to claim 5, characterized in that, The mud bed pressurization system acts on the slurry in the bottom straight section, and the pressurization method includes one or more of ballast, vacuum negative pressure, vibration or tamping; preferably, ballast is achieved by hydraulic means.

8. The ultra-consolidated high-efficiency thickener according to claim 5, characterized in that, When the pressurization method is ballast or overall vacuum negative pressure, it also includes a liftable isolation plug located at the top of the bottom straight section, which serves as the actuating component for ballast or the sealing component for evacuating the bottom slurry as a whole.

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