High-density precipitation system for contact oxidation coupling rapid coagulation

Abstract

The invention belongs to the technical field of water treatment, and particularly relates to a high-density precipitation system for contact oxidation coupling rapid coagulation. Comprising a main reaction system and an auxiliary carbon mud activation system, the main reaction system comprises a water inlet pipe, an activated carbon adsorption feeding point, an activated carbon mud contact oxidation chamber, a mixing chamber, a mechanical flocculation chamber and a precipitation separation chamber which are sequentially connected along the water flow direction; the auxiliary carbon mud activation system comprises an auxiliary carbon mud activation reactor and a micro-ozone aeration generator, the auxiliary carbon mud activation reactor is connected with the micro-ozone aeration generator, and the auxiliary carbon mud activation reactor is respectively connected with the precipitation separation chamber and the activated carbon mud contact chamber. Through organic coupling of contact oxidation and coagulation of the activated carbon mud, efficient contact adsorption oxidation of the activated carbon mud and organic matters, rapid mixing flocculation of a coagulant and suspended solids and efficient floc coagulation and separation are realized, and the removal efficiency of new pollutants and conventional pollutants in water and the capacity of resisting water quality and water quantity change loads are improved.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, specifically relating to a high-density sedimentation system with contact oxidation coupled with rapid coagulation. Background Technology

[0002] High-density sedimentation is a water purification technology that achieves efficient coagulation and rapid sedimentation separation of low-turbidity raw water by promoting flocculation through the recirculation of sedimented sludge. This technology recirculates a portion of the activated sludge discharged from the sedimentation tank back to the flocculation unit to increase the concentration and particle size of particulate matter in the water, improve the collision probability between suspended colloidal particles, and enhance the flocculation effect of low-turbidity raw water, forming larger, easily settling flocs. This achieves rapid and efficient sedimentation separation of turbid flocs, resulting in lower effluent turbidity and better effluent quality. In high-density sedimentation, the hydraulic conditions of coagulation and the activity of the recirculated sludge directly affect the destabilization and flocculation effect of colloidal particles in the water, thereby influencing the size, density, settling performance, and removal efficiency of dissolved organic pollutants in the water.

[0003] Existing traditional sludge recirculation high-density sedimentation systems for treating low-turbidity water, especially under ultra-low turbidity conditions (turbidity below 5 NTU), have the following main problems: 1. Under ultra-low turbidity conditions, the coagulation reaction is difficult to form flocs with large particle size and excellent settling performance, resulting in poor floc settling effect and ultimately high turbidity in the effluent; 2. The recirculated sludge contains a certain amount of natural organic matter, which undergoes anaerobic fermentation when it remains in the sedimentation tank or sludge storage and equalization tank for a long time. Especially under high-temperature conditions in summer, direct recirculation of anaerobic fermented sludge can easily lead to a significant increase in the concentration of chemical odorants and organic matter in the effluent; 3. The destabilized recirculated sludge flocs are prone to breakage during the rapid flocculation and stirring stage. The broken flocs are difficult to flocculate and settle again, resulting in the inability to effectively guarantee the effluent turbidity; 4. Although the recirculated sludge can enhance the removal effect of turbid particles to some extent by increasing the collision probability of flocs during the flocculation stage, its ability to remove low-concentration or even trace amounts of emerging pollutants is very limited and cannot meet higher treatment requirements.

[0004] Therefore, when traditional sludge recirculation high-density sedimentation systems have poor coagulation hydraulic conditions or poor sludge activity, it is difficult to form large and dense flocs, resulting in poor sedimentation and separation effects, increased turbidity and organic matter content in the effluent, and even foul odors. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a high-density sedimentation system that couples contact oxidation with rapid coagulation. By organically coupling activated carbon adsorption, activated carbon sludge contact oxidation, rapid and efficient coagulation, and high-density sedimentation, this system achieves efficient contact adsorption and oxidation of activated carbon sludge and organic matter, rapid mixing of coagulants and suspended colloids, and the formation of dense flocs that are easy to settle and separate. This improves the removal efficiency of both new and conventional pollutants in water and enhances the high-density sedimentation process's ability to withstand changes in water quality and quantity.

[0006] The present invention solves the above-mentioned technical problems through the following technical solutions.

[0007] The purpose of this invention is to provide a high-density sedimentation system for contact oxidation coupled with rapid coagulation, comprising a main reaction system and an auxiliary carbon sludge activation system connected sequentially along the water flow direction.

[0008] The main reaction system includes an inlet pipe, an activated carbon adsorption dosing point, an activated carbon sludge contact oxidation chamber, a mixing chamber, a mechanical flocculation chamber, and a sedimentation separation chamber connected sequentially along the water flow direction. Activated carbon is added at the activated carbon dosing point. The activated carbon sludge contact oxidation chamber and the mixing chamber bring the raw water to be treated, activated carbon, and activated carbon sludge into contact and couple for adsorption and oxidation. The mechanical flocculation chamber mixes and flocculates to form flocs that settle and separate. The sedimentation separation chamber separates the concentrated precipitated carbon sludge and discharges it, as well as transporting it to the auxiliary carbon sludge activation system.

[0009] The auxiliary carbon sludge activation system includes an auxiliary carbon sludge activation reactor and a micro ozone aerator. The auxiliary carbon sludge activation reactor is connected to the micro ozone aerator, and the auxiliary carbon sludge activator is connected to the sedimentation separation chamber and the activated carbon sludge contact oxidation chamber, respectively. After the sedimented carbon sludge is activated and regenerated, it is transported to the activated carbon sludge contact oxidation chamber.

[0010] Furthermore, the activated carbon sludge contact oxidation chamber is connected to the mixing chamber via a guide pipe. The water flow velocity between the activated carbon sludge contact oxidation chamber and the mixing chamber is 2 m / s to 4 m / s, the water flow velocity between the mixing chamber and the mechanical flocculation chamber is 0.6 m / s to 0.8 m / s, and the water flow velocity between the mechanical flocculation chamber and the sedimentation separation chamber is 0.1 m / s to 0.3 m / s.

[0011] Furthermore, an activated carbon dosing system is provided at the activated carbon dosing point, with an activated carbon dosing amount of 2 mg / L to 5 mg / L. The activated carbon sludge contact chamber is equipped with a first stirrer, with a speed gradient of 100 to 120 s. -1 .

[0012] Furthermore, a mixing shroud is provided in the mixing chamber, and a second stirrer is rotatably mounted inside the mixing shroud. The speed gradient of the second stirrer is 500 s. -1 ~900s -1The blade diameter ratio of the shroud and the second agitator is 1.2 to 1.5:1. The side wall end of the shroud is provided with an opening, the opening ratio is 40% to 50%, and the opening diameter is 3cm to 5cm.

[0013] Furthermore, the mixing chamber is equipped with a coagulant dosing system, with a coagulant dosing amount of 10mg / L to 25mg / L. The coagulant dosing system is equipped with a jet mixing unit, which is used to mix the coagulant and the influent and then pressurize and deliver it to the influent pipe. The jet outlet velocity is 3m / s to 5m / s.

[0014] Furthermore, the mechanical flocculation chamber is equipped with a flocculant dosing system and a third agitator. The flocculant dosage is 0.1 mg / L to 0.5 mg / L, and the velocity gradient of the third agitator is 80 s. -1 ~120s -1 The third agitator is equipped with a guide tube, and the ratio of the diameter of the guide tube to the diameter of the agitator blade is 1.4 to 1.6:1.

[0015] Furthermore, along the height direction, the sedimentation separation chamber is equipped with perforated water collection pipes, inclined tube sedimentation zone, and sludge thickening and discharge zone in sequence from top to bottom. The surface loading rate of the inclined tube sedimentation zone is 2.0 mm / s to 3.0 mm / s, the water depth above the inclined tube sedimentation zone is 1.0 m to 1.2 m, the water depth below the inclined tube sedimentation tank is 1.0 m to 1.2 m, and the height of the sludge thickening and discharge zone is 0.7 m to 1.0 m.

[0016] Furthermore, the auxiliary carbon sludge activator is equipped with a micro ozone aeration device and a biofilm fiber packing. The upper part of the auxiliary carbon sludge activator is connected to the sludge thickening and sludge discharge zone to activate and regenerate the precipitated carbon sludge separated in the sludge thickening and sludge discharge zone. The bottom of the auxiliary carbon sludge activator is connected to the activated carbon sludge contact oxidation chamber through a carbon sludge return pipe, and the micro ozone aeration device is connected to the micro ozone aeration generator.

[0017] Furthermore, the activation time of the precipitated charcoal sludge is 4h to 6h, the ozone aeration rate is 0.05mg / L to 0.15mg / L, and the charcoal sludge return flow rate is 2% to 4% or 20mg / L to 40mg / L dry weight.

[0018] Compared with the prior art, the present invention has the following advantages: This invention utilizes a coupled process of activated carbon sludge-loaded microbial adsorption and contact oxidation, high-speed mixing and flocculation, and efficient sedimentation. Raw water sequentially flows through activated carbon adsorption, activated carbon sludge contact oxidation, high-speed jet mixing, mechanical flocculation, and high-density sedimentation. Activated carbon, activated carbon sludge, and suspended colloidal organic matter undergo thorough contact adsorption and oxidation, enhancing the effectiveness of microbial contact adsorption and oxidation in removing organic pollutants from water during coagulation and sedimentation. The mixer and flocculant, equipped with a high-speed jet injector and rectifier, not only reduce reactor operating energy consumption but also achieve rapid and efficient mixing and flocculation of water treatment agents and suspended colloidal pollutants, as well as layer-by-layer adsorption of pollutants. This ultimately forms highly dense flocs that are easy to settle and separate, significantly improving the coagulation and sedimentation process's resilience to water quality changes and its water purification effect.

[0019] The high-density sedimentation system provided by this invention, which couples contact oxidation with rapid coagulation, achieves pre-adsorption of some dissolved organic matter and new pollutants in the raw water to be treated by adding a small amount (trace amount) of powdered activated carbon. After these pollutants enter the activated carbon sludge contact oxidation chamber with the activated carbon, conventional pollutants and new pollutants in the water are further adsorbed by the extracellular polymers of microorganisms on the surface of the activated carbon sludge. Under the action of the activated carbon sludge microorganisms, some organic matter is oxidized and degraded by the microorganisms.

[0020] The high-density sedimentation system provided by this invention, which uses a jet injector and a stirrer with a rectifier in the mixing chamber, achieves thorough collision and mixing of pollutants such as microbial activated carbon sludge, activated carbon, suspended colloids, and organic matter through mechanical stirring and rectification, based on the high-speed collision and mixing of coagulant and raw water, thus rapidly destabilizing them. After entering the mechanical flocculation chamber, the carbon sludge acts as the core carrier, constantly colliding with the flocculant and pollutants such as turbid colloids in the water during vigorous stirring. This easily forms small, dense, and resistant flocs that are easy to settle and separate. Subsequently, during low-speed collisions, dissolved pollutants in the water are adsorbed again, and the size of the flocs continuously increases. Finally, the system enters the sedimentation separation chamber, where efficient solid-liquid separation is achieved, resulting in sedimented effluent with effective and stable control of turbidity, organic matter, and other conventional pollutants, as well as new pollutants.

[0021] The high-density sedimentation system provided by this invention, which combines contact oxidation with rapid coagulation, adds an auxiliary carbon sludge activator compared to traditional high-density sedimentation processes. This activator incorporates micro-ozone aeration oxidation and biofilm-forming fiber packing. Micro-ozone aeration not only converts organic matter in the sedimented sludge into smaller molecules that are easily degraded by microorganisms, but the oxygen generated also provides an aerobic environment to promote the growth of aerobic microorganisms in the returned carbon sludge, achieving activation of the returned carbon sludge and moderate degradation of organic matter. The biofilm-forming fiber packing not only adsorbs and retains some organic matter, facilitating the growth of the microbial biofilm, but also provides a carrier for carbon sludge activation, ensuring the biomass and activity of microorganisms in the returned carbon sludge. This system not only reduces the dosage of activated carbon and ozone but also maximizes their utilization, resulting in a low-carbon, low-energy-consumption, and highly efficient enhanced coagulation technology. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the high-density sedimentation tank for contact oxidation coupling rapid coagulation according to the present invention.

[0023] Illustration: 1. Activated carbon adsorption dosing point; 2. Activated carbon sludge contact oxidation chamber; 3. Mixing chamber; 4. Mechanical flocculation chamber; 5. Sedimentation and separation chamber; 6. Perforated water collection pipe; 7. Sludge thickening and discharge area; 8. Auxiliary carbon sludge activator; 9. Micro ozone aerator; 1-1. First guide wall plate; 1-2. Second guide wall plate; 1-3. Third guide wall plate. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that the technical terms used in this invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods.

[0026] It should be noted that the technical terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of this invention. Certain terms are used in this invention to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component.

[0027] The following specific examples will provide further explanation.

[0028] Example 1 This invention provides a high-density precipitation system for contact oxidation coupled with rapid coagulation, such as... Figure 1 As shown, it includes a main reaction system and an auxiliary carbon mud activation system 8 connected sequentially along the water flow direction.

[0029] The main reaction system is used to adsorb, oxidize, and couple rapid coagulation of activated carbon sludge to adsorb, oxidize, mix, flocculate, and separate organic pollutants in water. It includes an inlet pipe, activated carbon adsorption dosing point 1, activated carbon sludge contact oxidation chamber 2, mixing chamber 3, mechanical flocculation chamber 4, and sedimentation separation chamber 5, connected sequentially along the water flow direction. Activated carbon dosing point 1 is located on the inlet pipe. Activated carbon sludge contact oxidation chamber 2 and mixing chamber 3 are connected. The bottom of mixing chamber 3 is connected to the bottom of mechanical flocculation chamber 4, and the bottom of mechanical flocculation chamber 4 is connected to the bottom of sedimentation separation chamber 5. Activated carbon is added at activated carbon dosing point 1. The activated carbon sludge contact oxidation chamber 2 and mixing chamber 3 bring the raw water, activated carbon, and activated carbon sludge into contact and couple for adsorption and oxidation. Mechanical flocculation chamber 4 mixes and flocculates to form settled flocs. Sedimentation separation chamber 5 separates the sediment, discharging the concentrated precipitated carbon sludge and transporting it to the auxiliary carbon sludge activation system.

[0030] The auxiliary carbon sludge activation system includes an auxiliary carbon sludge activation reactor 8 and a micro ozone aerator 9. The auxiliary carbon sludge activation reactor 8 is connected to the micro ozone aerator 9. The auxiliary carbon sludge activator 8 is connected to the bottom of the sedimentation separation chamber 5 and the top of the activated carbon sludge contact oxidation chamber 2. After the sedimented carbon sludge is activated and regenerated, it is transported to the activated carbon sludge contact oxidation chamber 2.

[0031] The main reaction tank is used for contact oxidation of activated carbon sludge coupled with coagulation and sedimentation to remove turbidity and organic pollutants in water through adsorption, contact oxidation, mixing, flocculation, and sedimentation. The main reaction tank is sequentially divided into three sections along the water flow direction: a first guide wall 1-1, a second guide wall 1-2, and a third guide wall 1-3, forming an activated carbon sludge contact oxidation chamber 2, a high-speed jet rapid mixing chamber 2, a mechanical flocculation chamber 4, and a sedimentation separation chamber 5. The activated carbon adsorption dosing point 1 is located on the inlet pipe, which is situated at the top of the activated carbon sludge contact chamber 2. The bottom of the activated carbon sludge contact chamber 2 is connected to the bottom of the mixing chamber 3 via a guide pipe. The bottom of the mixing chamber 3 is connected to the bottom of the mechanical flocculation chamber 4. The bottom of the mechanical flocculation chamber 4 is connected to the sedimentation separation chamber 5. The bottom of the chamber is connected, and a first guide channel is provided between the mixing chamber 3 and the mechanical flocculation chamber 4, while a second guide channel is provided between the mechanical flocculation chamber 4 and the sedimentation separation chamber 5. After the raw water to be treated is fully mixed and reacted with the powdered activated carbon, it enters from the top of the activated carbon sludge contact oxidation chamber 2. Through stirring and agitation, the suspended colloids, powdered activated carbon, and activated carbon sludge in the water are fully contacted and oxidized. The effluent from the bottom of the activated carbon sludge contact oxidation chamber 2 is rapidly injected into the mixing chamber 3 through the guide pipe to form a high-speed jet. In the mixing chamber 3, under the conditions of high-speed jet and rectification stirring, the coagulant and the raw water containing activated carbon sludge are rapidly and fully collided and mixed, achieving low-energy consumption, rapid, and efficient mixing and contact oxidation of pollutants such as microbial activated carbon sludge, activated carbon, suspended colloids, and organic matter. Then, the effluent from the mixing chamber 3 enters the mechanical flocculation chamber 4. The mechanical flocculation chamber 4 uses activated carbon sludge as the core carrier, and the flocculant and the turbid colloidal pollutants in the influent are continuously collided during vigorous stirring, which easily forms small, dense, and non-breakable flocs that are easy to settle and separate. During the low-speed collision process, the flocs re-adsorb dissolved pollutants in the water and their size continues to increase. They eventually enter the sedimentation separation chamber 5, where efficient solid-liquid separation is achieved. The supernatant is discharged and concentrated. Some of the precipitated carbon sludge enters the auxiliary carbon sludge activator 8 for activation and regeneration. The remaining precipitated carbon sludge is discharged from the sedimentation separation chamber 5. In the auxiliary carbon sludge activator 8, under the combined action of micro-ozone aeration oxidation and biofilm fiber packing, the carbon sludge achieves moderate biochemical oxidation and aerobic biodegradation of organic matter. Those with good microbial activity are activated and regenerated and returned to the activated carbon sludge contact chamber 2.

[0032] This invention utilizes a coupled process of activated carbon sludge-loaded microbial adsorption and contact oxidation, high-speed mixing and flocculation, and efficient sedimentation. Raw water sequentially flows through activated carbon adsorption, activated carbon sludge contact oxidation, high-speed jet mixing, mechanical flocculation, and high-density sedimentation. Activated carbon, activated carbon sludge, and suspended colloidal organic matter undergo thorough contact adsorption and oxidation, enhancing the effectiveness of microbial contact adsorption and oxidation in removing organic pollutants from water during coagulation and sedimentation. The mixer and flocculant, equipped with a high-speed jet injector and rectifier, not only reduce reactor operating energy consumption but also achieve rapid and efficient mixing and flocculation of water treatment agents and suspended colloidal pollutants, as well as layer-by-layer adsorption of pollutants. This ultimately forms highly dense flocs that are easy to settle and separate, significantly improving the coagulation and sedimentation process's resilience to water quality changes and its water purification effect.

[0033] In a specific embodiment, the bottom of the activated carbon sludge contact chamber 2 and the bottom of the mixing chamber 3 are connected by a guide pipe. The water flow velocity between the activated carbon sludge contact oxidation chamber 2 and the mixing chamber 3 is 2 m / s to 4 m / s, the water flow velocity between the mixing chamber 3 and the mechanical flocculation chamber 4 is 0.6 m / s to 0.8 m / s, and the water flow velocity between the mechanical flocculation chamber 4 and the sedimentation separation chamber 5 is 0.1 m / s to 0.3 m / s. That is, the flow velocity of the effluent through the guide pipe is controlled at 2 m / s to 4 m / s, the flow velocity of the effluent through the first guide channel is controlled at 0.6 m / s to 0.8 m / s, and the flow velocity of the effluent through the second guide channel is controlled at 0.1 m / s to 0.3 m / s.

[0034] In a specific embodiment, an activated carbon dosing system is provided at the activated carbon dosing point 1, and the activated carbon dosing amount is 2 mg / L to 5 mg / L. The activated carbon sludge contact chamber 2 is provided with a first stirrer, and the speed gradient of the first stirrer is 100 s. -1 ~120s -1 The returned activated carbon sludge enters the carbon sludge contact chamber 2 together with the influent containing activated carbon. The addition of activated carbon can effectively adsorb trace organic matter and turbid pollutants in the water and eliminate any unpleasant odor that may exist in the returned carbon sludge. At the same time, aerobic microorganisms in the contact oxidation chamber degrade organic pollutants in the water through adsorption and contact oxidation. The activated carbon dosing system is a conventional chemical dosing control system, mainly including an activated carbon storage tank and a dosing meter. This invention does not limit the specific method of the activated carbon dosing system, as long as the activated carbon dosing amount is between 2 mg / L and 5 mg / L.

[0035] In this invention, the contact oxidation mechanism of activated carbon mud contact oxidation chamber 2 mainly follows the contact oxidation degradation mechanism of aerobic sludge microorganisms, which can be divided into two main processes: (1) Contact adsorption process, where suspended colloidal organic matter in water is adsorbed and adhered to pollutants in water under the action of microbial film on the surface of activated carbon mud and secreted extracellular polysaccharide polymers. The addition of new active ingredients can enhance the adsorption of organic matter; (2) Oxidative degradation process, where microorganisms on the surface of activated carbon mud, under the oxygen-rich conditions of the stirrer, oxidize and degrade adsorbed organic pollutants through their own metabolism.

[0036] In a specific embodiment, a mixing chamber 3 is provided with a mixing rectifier, and a second stirrer is rotatably mounted inside the mixing rectifier. The speed gradient of the second stirrer is 500 s. -1 ~900s -1The blade diameter ratio of the rectifier and the second agitator is 1.2–1.5:1. The sidewall of the rectifier has openings with an opening ratio of 40%–50% and an opening diameter of 3–5 cm. The mixing chamber 3 also includes a coagulant dosing system with a coagulant dosage of 10 mg / L–25 mg / L. This system includes a jet mixing unit that mixes the coagulant and influent water and then pressurizes and delivers the mixture to the influent pipe. The outlet flow velocity of the jet mixing unit is 3 m / s–5 m / s. The coagulant is a conventional water treatment agent, such as liquid polyaluminum chloride coagulant. The coagulant dosing system is a conventional agent dosing control system, mainly including an activated carbon storage tank and a dosing meter. This invention does not limit the specific method of the activated carbon dosing system, as long as the coagulant dosage is 10 mg / L–25 mg / L. To achieve instantaneous mixing of coagulant, influent, and activated carbon sludge, the jet mixing unit includes an ejector and a booster pump. The ejector and booster pump are connected via an outlet pipe. The ejector baffle is fixed to the lower part of the second agitator. The ejector baffle is circular with the same diameter as the blades of the second agitator, and its bottom is conical at 90°. After the coagulant is added, high-speed raw water at a flow ratio of 1:20 is added through the metering device and enters the mixing chamber 3. The water from the activated carbon sludge contact chamber 2 collides at the jet baffle, passes through the ejector, and is then mixed with the coagulant by the booster pump in a small amount of high-speed raw water before being jet-mixed again with the treated water containing activated carbon sludge. This achieves stepwise mixing of pollutants with the coagulant and coagulation carrier. A rectifier is installed on the second agitator. The diameter of the rectifier is smaller than that of the blades of the second agitator, making it easy for the primary mixed water to form a high-speed mixing state. Instantaneous mixing is achieved through the rapid disturbance of the blades of the second agitator without increasing energy consumption. Then, the jet overflows from the rectifier opening in a jet vortex shape. The smaller opening ratio and opening diameter increase the mixing jet speed, making the mixing more thorough, forming small vortices to transfer energy again and form micro flocs, promoting the coagulation of flocs. In this invention, the high-speed mixing and flocculation mechanism of mixing chamber 3 mainly follows the instantaneous destabilization and rapid flocculation mechanism, which can be divided into four main processes: (1) Rapid step-by-step mixing process, the coagulant is initially mixed with some high-speed raw water, and then mixed with pretreated water containing activated carbon mud at the outlet baffle of the jet injector to achieve the initial mixing and destabilization of pollutants with coagulant and coagulation carrier; (2) Instantaneous destabilization mixing process, the colloidal suspended matter in the water enters the rectifier and is instantly mixed and destabilized under the action of rapid stirring and coagulant; (3) Vortex mass transfer destabilization process, the rapidly disturbed water flow in the rectifier forms micro vortices at the edge of the opening to further destabilize the colloidal suspended matter in the water; (4) Destabilized floc flocculation process, the destabilized micro flocs continuously collide during the rapid flocculation and stirring process to form dense and smaller flocs.

[0037] In a specific embodiment, the mechanical flocculation chamber 4 is equipped with a flocculant dosing system and a third agitator. The flocculant dosing amount is 0.1 mg / L to 0.5 mg / L, and the speed gradient of the third agitator is 80 s.-1 ~120s -1 The third agitator is equipped with a guide tube, and the ratio of the diameter of the guide tube to the diameter of the agitator blade is 1.4 to 1.6:1.

[0038] In this invention, the flocculant dosing system is a conventional reagent dosing control system, mainly including a flocculant stirring and storage tank and a dosing meter. The invention does not limit the specific method of the flocculant dosing system, as long as the flocculant dosage is between 0.1 mg / L and 0.5 mg / L. This invention, by setting a relatively small ratio between the diameter of the guide tube and the diameter of the agitator blades, allows the flocculant and turbid colloidal pollutants in the influent to collide continuously during vigorous stirring in the agitator. This facilitates the formation of small, dense, and easily settled flocs that are not easily broken. Under the action of flocculant and flocculation collisions, the small flocs continuously grow, forming large, dense, and easily settled flocs. During the low-speed propulsion and collision process outside the guide tube, the flocs re-adsorb dissolved pollutants in the water and continuously increase in size, gradually forming large, dense, and easily settled flocs. The flocs, along with the effluent, enter the sedimentation separation chamber 5, achieving solid-liquid separation.

[0039] In a specific embodiment, the sedimentation separation chamber 5 is provided with a perforated water collection pipe 6, an inclined tube sedimentation zone, and a sludge thickening and discharge zone 7 in sequence from top to bottom along the height direction. The surface loading rate of the inclined tube sedimentation zone is 2.0 mm / s to 3.0 mm / s, the effective water depth above the inclined tube sedimentation zone is 1.0 m to 1.2 m, and the effective water depth below the inclined tube sedimentation zone is 1.0 m to 1.2 m. In this invention, when the flocs enter the sedimentation separation chamber 5, solid-liquid separation is performed through the inclined tube sedimentation zone. The supernatant is collected by the perforated water collection pipe 6 and flows into the clear water channel. The sludge thickening and discharge zone 7 is the sludge thickening, collection, and discharge system, which thickens the sludge. More specifically, a scraper and a rake are installed at the bottom of the sludge thickening and discharge zone 7 to achieve the thickening of the settled carbon sludge. The settled carbon sludge is finally discharged through the bottom discharge pipe. Part of the carbon sludge enters the auxiliary carbon sludge activator 8 for activation and regeneration, and flows back to the activated carbon sludge contact chamber 2. The remaining carbon sludge is discharged from the system.

[0040] The efficient sedimentation mechanism mainly follows the slow growth of flocs and the separation mechanism of inclined tube sedimentation, which can be divided into two main processes: (1) the slow growth process of flocs, in which small and dense flocs grow continuously in the hydraulic flocculation stage, further capturing and sweeping suspended colloidal pollutants in the water; (2) the sedimentation separation process of flocs, in which large and dense flocs are separated from the water under the action of gravity and crowd to settle, in which the separation of turbid particles in the water and the supernatant is completed, realizing efficient water purification. In order to ensure the effect of solid-liquid separation and achieve water purification and clarification, the effective water depth above the inclined tube sedimentation zone is 1.0-1.2m, the height of the inclined tube zone is 0.5m, the effective water depth below the inclined tube sedimentation tank is 1.0m-1.2m, and the height of the sludge thickening and sludge discharge zone 7 is 0.7m-1.0m. This is conducive to solid-liquid separation, floc floating and carbon sludge floc settling, and ensures the effluent effect.

[0041] In a specific embodiment, the auxiliary carbon sludge activator 8 is equipped with a biofilm fiber packing material and a micro-ozone aeration device. The upper part of the auxiliary carbon sludge activator 8 is connected to the sludge thickening and discharge zone 7 to activate and regenerate the precipitated carbon sludge separated in the sludge thickening and discharge zone. The bottom of the auxiliary carbon sludge activator 8 is connected to the activated carbon sludge contact oxidation chamber 2 through a carbon sludge return pipe. The micro-ozone aeration device is connected to the micro-ozone aeration generator 9. In this invention, the bottom of the auxiliary carbon sludge activation tank 8 is equipped with a sludge return pipe, and a sludge lift pump is installed on the sludge return pipe. The sludge is pressurized and transported to the activated carbon sludge contact oxidation chamber 2 by the sludge lift pump. The aeration pipe is equipped with a control valve and a flow metering device. The connection between the aeration pipe and the auxiliary carbon sludge activator 8 is located 15cm to 25cm above the bottom of the tank.

[0042] In a specific embodiment, the auxiliary carbon sludge activator 8 has an aspect ratio of 1:1 to 1.5, a water depth of 1.5m to 2.0m, a carbon sludge activation time of 4h to 6h, an ozone aeration rate of 0.05mg / L to 0.15mg / L, and a carbon sludge return flow rate of 2% to 4%.

[0043] In a specific embodiment, flow meters and control valves are installed on the raw water inlet pipe, the activated carbon sludge return pipe, and the ozone aeration pipe. In this invention, the connection between the ozone aeration pipe and the auxiliary activated carbon sludge device 8 is located 15cm to 25cm above the bottom of the activated carbon sludge device, and the connection between the activated carbon sludge return pipe and the auxiliary activated carbon sludge device 8 is located 50cm to 60cm above the bottom of the activated carbon sludge device.

[0044] In summary, this invention fully utilizes the advantages of activated carbon sludge contact oxidation, rapid mixing, and high-density sedimentation, integrating activated carbon adsorption, microbial activated carbon sludge contact oxidation, instantaneous coagulation adsorption, and efficient solid-liquid separation processes. Compared to existing high-density sedimentation processes, by improving the activity of returned carbon sludge and oxidizing and degrading pollutants in returned carbon sludge, it effectively reduces the risk of chemical odorants and organic pollution that may be carried by returned sludge. Using activated carbon sludge as a carrier can also solve the problem of low-turbidity water having difficulty forming large-particle-size, easily settling flocs. While saving on activated carbon, coagulants, and ozone dosage, it reduces the energy consumption of mechanical stirring in the system, enhances the ability of the high-density sedimentation process to cope with changes in water quality, and has a good treatment effect on raw water of different qualities. It can not only remove turbid particulate matter but also has a good ability to remove new pollutants. The advantages of this contact oxidation coupled with rapid coagulation high-density sedimentation system are summarized as follows:

[0045] (1) Highly efficient mixing reaction and rapid destabilization of pollutants: The system has been specifically optimized in the structural design of the mixing chamber, and innovatively set up a jet injector and a stirrer with a rectifier to construct a dual high-efficiency mixing mechanism. First, the jet injector realizes high-speed collision mixing of coagulant and raw water, allowing the agent to diffuse rapidly; on this basis, the stirrer with a rectifier breaks the dead zone of water flow through mechanical stirring and rectification, and promotes full contact and collision of various pollutants such as microbial activated carbon sludge, activated carbon, suspended colloids, and organic matter, which completely solves the problem of uneven mixing and insufficient reaction of pollutants in traditional mixing methods, promotes rapid destabilization of various pollutants, lays a solid foundation for subsequent flocculation and sedimentation processes, significantly shortens the time required for mixing reaction, and improves the treatment efficiency of the entire system.

[0046] (2) Excellent floc performance and good sedimentation and separation: The system uses carbon mud as the core carrier and gradually optimizes the flocs throughout the flocculation process to ensure excellent sedimentation and separation performance. After the raw water enters the mechanical flocculation chamber, the carbon mud, as the core carrier, colloids with pollutants such as turbidity colloids in the water under the action of flocculant. Compared with traditional processes, it is easier to form small and dense flocs. Moreover, the structure of such flocs is stable and not easy to break, which solves the problem of traditional flocs being easy to disperse and difficult to settle from the root. Subsequently, in the low-speed collision stage, the flocs further adsorb dissolved pollutants in the water, while their size continues to increase, forming an optimized structure of "small and dense - large and solid". After entering the sedimentation separation chamber, it can quickly achieve efficient solid-liquid separation, significantly improving sedimentation efficiency and separation effect.

[0047] (3) Effective removal of conventional pollutants and control of new pollutants: The system adopts a multi-process coupling design concept to construct a comprehensive pollutant removal system, ensuring that the effluent water quality is stable and meets the standards. The raw water flows sequentially through multiple stages such as activated carbon adsorption, activated carbon sludge contact oxidation, high-speed jet rapid mixing, mechanical flocculation, and high-density sedimentation, achieving full contact, adsorption, and oxidation of various substances such as activated carbon, activated carbon sludge, suspended colloids, and organic matter. This synergistic effect can not only efficiently remove conventional pollutants such as turbidity and organic matter in the water, but also effectively control new pollutants, solving the pain points of insufficient removal capacity of new pollutants and large fluctuations in effluent water quality in traditional processes. Finally, high-quality sedimented effluent with stable control of pollutants such as turbidity and organic matter is obtained, meeting higher water purification standards.

[0048] (4) Full activation of carbon sludge and maximum utilization of resources: Compared with the traditional high-density sedimentation process, this system adds an auxiliary carbon sludge activator and is equipped with micro-ozone aeration oxidation and biofilm fiber packing, realizing efficient activation and resource recycling of the returned carbon sludge. Among them, the role of micro-ozone aeration is dual: on the one hand, it can convert the organic matter in the sedimented sludge into small molecule organic matter that is easily degraded by microorganisms, reducing the pollutant load; on the other hand, the oxygen generated by ozone reduction can provide a sufficient aerobic environment, promote the growth and reproduction of aerobic microorganisms in the returned carbon sludge, effectively activate the activity of the returned carbon sludge, and achieve moderate degradation of organic matter. The biofilm fiber packing plays a dual role of "adsorption + carrier". It can adsorb and retain some organic matter, provide nutrients for the growth of microbial film, and also serve as a carrier for carbon sludge activation, ensuring the quantity and activity of microorganisms in the returned carbon sludge, avoiding carbon sludge deactivation, and maximizing the treatment efficiency of the returned carbon sludge.

[0049] (5) Reduced reagent consumption and energy consumption, low-carbon and high-efficiency process: Through structural optimization and process synergy, the system achieves a dual reduction in reagent consumption and operating energy consumption, constructing a low-carbon and low-energy enhanced coagulation technology system. In terms of reagent consumption, the setting of the carbon sludge activator significantly improves the activity of the returned carbon sludge and increases the amount of microorganisms, which can give full play to the adsorption and degradation effects, thereby effectively reducing the dosage of activated carbon and ozone, while maximizing the utilization efficiency of the two reagents and avoiding resource waste. In terms of energy consumption control, the combination of jet nozzle and agitator with rectifier in the mixing chamber and the staged stirring design of the mechanical flocculation chamber, compared with the traditional process, can achieve rapid mixing and flocculation of pollutants, and reduce the operating energy consumption of the reactor. It can achieve the ideal treatment effect without excessive mechanical power, taking into account both treatment efficiency and energy saving requirements.

[0050] (6) Strong process resistance and improved water purification effect: Through multi-stage optimized design, the system significantly improves the ability of coagulation and sedimentation process to resist the risk of water quality changes, and further enhances the water purification effect. On the one hand, the mixer and flocculant with high-speed jet and rectifier realize the rapid and efficient mixing and flocculation of water treatment agents and suspended colloidal pollutants, ensuring that even if the raw water quality fluctuates, the agents can quickly take effect and the pollutants can be destabilized and flocculated in time. On the other hand, through the layer-by-layer adsorption of pollutants (activated carbon adsorption - activated carbon sludge contact oxidation - floc adsorption), the role of microbial contact adsorption oxidation in the coagulation and sedimentation process is strengthened, further improving the removal effect of organic pollutants in the water, avoiding the failure of effluent quality due to water quality fluctuations, ensuring the long-term stable operation of the entire system, and continuously outputting high-quality effluent.

[0051] Application Example 1 The high-density sedimentation tank with contact oxidation coupled with high-speed coagulation provided in Example 1 was used to treat Yellow River diversion water in a certain area. The raw water had a turbidity of 2.52 NTU and a COD of [missing information]. Mn UV 254 The concentrations of DOC were 3.59 mg / L, 0.040 mg / L, and 3.668 mg / L, respectively; the concentration of the new pollutant sulfadiazine was 100 ng / L; the pH value was 7.93–8.44; and the water temperature was 10.8℃–11.6℃.

[0052] The activated carbon dosage was 4 mg / L. In activated carbon sludge contact oxidation chamber 2, the water flow velocity was 1.2 m / s, the carbon sludge reflux ratio was 3%, the residence time was 30 min, and the G value in this stage was 110 s. -1 Some new pollutants and turbid colloids in the water are adsorbed and degraded by activated carbon and activated carbon sludge.

[0053] In the high-speed jet rapid mixing chamber 3, the water flow velocity is 2.5 m / s. PAC (polyaluminum chloride) coagulant is used at a dosage of 20 mg / L. The liquid coagulant solution is mixed with high-speed raw water at a flow ratio of 1:20. The mixture collides with the effluent from activated carbon sludge contact chamber 2 at the jet baffle, and the jet outlet velocity is 4 m / s. The blade diameter ratio of the shroud and the second agitator is 1.3:1. The upper opening ratio of the shroud is 50%, and the opening diameter is 3 cm. The mixing stage G-value is 750 s. -1 Within 30 seconds, the colloidal particles and turbidity in the water rapidly mix and destabilize with the coagulant.

[0054] In high-density mechanical flocculation chamber 4, the water flow velocity was 0.7 m / s, the flocculant used was PAM (polyacrylamide), the PAM dosage was 0.5 mg / L, and the G-value of the mechanical flocculation stage was 100 s. -1 The ratio of the diameter of the guide tube to the diameter of the agitator blade is 1.5:1. The reaction time is 15 minutes. The destabilized colloidal particles form micro-flocculation with carbon mud and activated carbon in the water as floc nuclei, which further adsorb, trap, and sweep, eventually forming dense and easily settling large flocs.

[0055] In sedimentation separation chamber 5, the surface velocity of inclined tube sedimentation zone 7 is -3.0 mm / s, the effective water depth above inclined tube sedimentation zone 7 is 1.0 m, the height of the inclined tube zone is 0.5 m, the effective water depth below the inclined tube sedimentation tank is 1.2 m, the height of sludge thickening and sludge discharge zone 8 is 0.7 m, the hydraulic retention time is 40 min, the floc concentration and settling performance are significantly improved, the water quality is purified by solid-liquid separation through inclined tube sedimentation, the purified water is collected and discharged through the clear water collection pipe, and the settled colloidal flocs enter the sludge collection zone and are discharged by the sludge discharge system.

[0056] In the auxiliary carbon sludge activation tank 8, the length-to-width ratio of the auxiliary carbon sludge activation tank 8 is 1:1.5, the water depth is 1.8m, the carbon sludge activation time is 6h, the ozone aeration rate is 0.1mg / L, and the carbon sludge return flow rate is 3%.

[0057] Using the above water purification method, when the PAM dosage is 0.5 mg / L, the relationship between the PAC dosage and the removal rate of various pollutants is shown in Table 1.

[0058] Table 1. Relationship between PAC dosage and removal rates of various pollutants Application Comparative Example 1 The difference from Application Example 1 is that the carbon sludge activation process and activated carbon addition process are omitted. After treatment, the same water to be purified is treated as a traditional high-density sedimentation process. The water purification effect is shown in Table 2.

[0059] Table 2 Relationship between PAC dosage and removal rates of various pollutants Application Comparative Example 2 The difference from Application Example 1 is that the jet injector and rectifier in mixing chamber 2 and the guide tube in mechanical flocculation chamber 4 are omitted, while the carbon sludge activation process and activated carbon addition process are retained. This is the adsorption contact oxidation enhanced coagulation high-efficiency sedimentation process. The water purification effect after treatment of the same water to be purified is shown in Table 3.

[0060] Table 3 Relationship between PAC dosage and removal rates of various pollutants As shown in Tables 1 to 3, the high-density sedimentation system with contact oxidation coupled with rapid coagulation has better effluent quality, lower PAFC dosage, and higher water purification efficiency compared to traditional high-density sedimentation and adsorption contact oxidation enhanced coagulation high-efficiency sedimentation processes.

[0061] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0062] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A high-density sedimentation system with contact oxidation coupled with rapid coagulation, characterized in that, This includes the main reaction system and the auxiliary carbon sludge activation system connected sequentially along the water flow direction; The main reaction system includes an inlet pipe, an activated carbon adsorption dosing point (1), an activated carbon sludge contact oxidation chamber (2), a mixing chamber (3), a mechanical flocculation chamber (4), and a sedimentation separation chamber (5) connected sequentially along the water flow direction. Activated carbon is added at the activated carbon dosing point (1). The activated carbon sludge contact oxidation chamber (2) and the mixing chamber (3) bring the raw water to be treated, activated carbon, and activated carbon sludge into contact and couple for adsorption and oxidation. The mechanical flocculation chamber (4) mixes and flocculates to form flocs that settle and separate. The sedimentation separation chamber (5) performs sedimentation separation, discharges the concentrated sedimented carbon sludge, and transports it to the auxiliary carbon sludge activation system. The auxiliary carbon mud activation system includes an auxiliary carbon mud activation reactor (8) and a micro ozone aerator (9). The auxiliary carbon mud activation reactor (8) is connected to the micro ozone aerator (9). The auxiliary carbon mud activator (8) is connected to the sedimentation separation chamber (5) and the activated carbon mud contact oxidation chamber (2) respectively. After the sedimented carbon mud is activated and regenerated, it is transported to the activated carbon mud contact oxidation chamber (2).

2. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 1, characterized in that, The activated carbon sludge contact oxidation chamber (2) is connected to the mixing chamber (3) through a guide pipe. The water flow velocity between the activated carbon sludge contact oxidation chamber (2) and the mixing chamber (3) is 2 m / s to 4 m / s. The water flow velocity between the mixing chamber (3) and the mechanical flocculation chamber (4) is 0.6 m / s to 0.8 m / s. The water flow velocity between the mechanical flocculation chamber (4) and the sedimentation separation chamber (5) is 0.1 m / s to 0.3 m / s.

3. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 1, characterized in that, An activated carbon dosing system is provided at the activated carbon dosing point (1), with an activated carbon dosing amount of 2 mg / L to 5 mg / L. The activated carbon sludge contact chamber (2) is equipped with a first stirrer with a speed gradient of 100 to 120 s. -1 .

4. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 1, characterized in that, The mixing chamber (3) is equipped with a mixing shroud, and a second stirrer is rotatably installed inside the mixing shroud. The speed gradient of the second stirrer is 500 s. -1 ~900s -1 The blade diameter ratio of the shroud and the second agitator is 1.2 to 1.5:

1. The side wall end of the shroud is provided with an opening, the opening ratio is 40% to 50%, and the opening diameter is 3cm to 5cm.

5. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 4, characterized in that, The mixing chamber (3) is equipped with a coagulant dosing system. The coagulant dosing amount is 10mg / L to 25mg / L. The coagulant dosing system is equipped with a jet mixing unit. The jet mixing unit is used to mix the coagulant and the influent and then pressurize and transport it to the influent pipe. The outlet flow velocity of the jet mixing unit is 3m / s to 5m / s.

6. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 1, characterized in that, The mechanical flocculation chamber (4) is equipped with a flocculant dosing system and a third agitator. The flocculant dosing amount is 0.1 mg / L to 0.5 mg / L, and the velocity gradient of the third agitator is 80 s. -1 ~120s -1 The third agitator is equipped with a guide tube, and the ratio of the diameter of the guide tube to the diameter of the agitator blade is 1.4 to 1.6:

1.

7. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 1, characterized in that, The sedimentation separation chamber (5) is provided with perforated water collection pipe (6), inclined tube sedimentation zone and sludge thickening and sludge discharge zone (7) in the vertical direction from top to bottom. The surface load of the inclined tube sedimentation zone is 2.0 mm / s to 3.0 mm / s. The water depth above the inclined tube sedimentation zone is 1.0 m to 1.2 m and the water depth below the inclined tube sedimentation zone is 1.0 m to 1.2 m. The height of the sludge thickening and sludge discharge zone (7) is 0.7 m to 1.0 m.

8. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 1, characterized in that, The auxiliary carbon sludge activator (8) is equipped with a micro ozone aeration device and a biofilm fiber packing. The upper part of the auxiliary carbon sludge activator (8) is connected to the sludge thickening and sludge discharge zone (7) to activate and regenerate the precipitated carbon sludge separated in the sludge thickening and sludge discharge zone. The bottom of the auxiliary carbon sludge activator (8) is connected to the activated carbon sludge contact oxidation chamber (2) through the carbon sludge return pipe. The micro ozone aeration device and the micro ozone aeration generator (9) are connected.

9. The high-density sedimentation system with contact oxidation coupling and rapid coagulation according to claim 8, characterized in that, The activation time for the precipitated charcoal sludge is 4h to 6h, the ozone aeration rate is 0.05mg / L to 0.15mg / L, and the charcoal sludge return flow rate is 2% to 4% or 20mg / L to 40mg / L dry weight.

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