An adjustable sludge concentration UASB reactor

Abstract

The utility model discloses a kind of UASB reactors of adjustable sludge concentration, including reactor body, lower layer three-phase separator is installed in the reactor body, water collecting pipeline is installed above the lower layer three-phase separator, upper layer adjustable three-phase separator is installed above the water collecting pipeline;Water collecting pipeline and inlet conduit are jointly connected in the inlet water line of circulating pump, the outlet of circulating pump is connected with water distribution pipe in the reactor body, sludge level gauge is installed at the top of the reactor body, for measuring reaction zone sludge concentration;Sludge level gauge is electrically connected to wisdom control system, the sludge concentration signal measured by the sludge level gauge is received by AI module of wisdom control system, the height of the upper layer adjustable three-phase separator to be adjusted is calculated accordingly, and the upper layer adjustable three-phase separator moves corresponding distance by AO module control, increase settling zone height, delay sludge settling time, prevent sludge loss, improve sludge concentration.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment equipment technology, and more specifically to a UASB reactor with adjustable sludge concentration. Background Technology

[0002] UASB technology, as a second-generation anaerobic reactor, is mainly used for high-concentration organic wastewater and is widely used due to its low energy consumption and other advantages. UASB degradation of organic matter in water mainly involves four stages: Stage 1: Hydrolysis, where soluble macromolecular and insoluble organic matter in the wastewater is hydrolyzed into soluble small-molecule organic matter; Stage 2: Acidification, where the soluble small-molecule organic matter formed by hydrolysis is used as a carbon and energy source by acid-producing bacteria, ultimately producing short-chain volatile acids, such as acetic acid; Stage 3: Hydrogen and acetic acid production, where the products of the previous stage are further converted into acetic acid; Stage 4: Methanogenesis, where acetic acid is converted into methane, carbon dioxide, and new cellular material, thereby achieving the removal of organic matter from the water.

[0003] Traditional UASB systems often use fixed three-phase separators, which make it difficult to adjust the separator size according to fluctuations in the influent load, resulting in a decrease in separation efficiency. After treatment by the anaerobic reactor, a sedimentation tank is also required for further mud-water separation.

[0004] A search revealed that Chinese utility model patent document (CN202346831U) discloses an adjustable three-phase separator. Based on the upflow velocity of liquid and gas in the settling zone of the reactor, the angle between the reflector and the horizontal direction can be adjusted by driving a lever to move the telescopic wall. This allows for the separation of gas, liquid, and solid phases, while simultaneously enabling the sludge separated from water in the settling zone to slide back into the reaction zone more efficiently along the inclined plate.

[0005] In practice, it has been found that the above-mentioned technical solutions have limited effectiveness in controlling sludge concentration. Utility Model Content

[0006] The technical problem to be solved by this utility model

[0007] In view of this, the purpose of this utility model is to provide a UASB reactor with adjustable sludge concentration, which can achieve more effective adjustment of sludge concentration through the coordinated operation of a circulating pump and an upper adjustable three-phase separator.

[0008] Technical solution

[0009] To achieve the above objectives, this utility model provides the following technical solution:

[0010] The present invention relates to an adjustable sludge concentration UASB reactor, comprising a reactor body, a lower three-phase separator installed inside the reactor body, a water collection pipe installed above the lower three-phase separator, and an upper adjustable three-phase separator installed above the water collection pipe.

[0011] The water collection pipe and the water inlet pipe are connected to the water inlet pipe of the circulating pump. The water outlet of the circulating pump is connected to the water distribution pipe inside the reactor body. A sludge discharge pipe is installed below the water distribution pipe and is connected to the sludge discharge pump.

[0012] Furthermore, the water collection pipe is equipped with an adjustable self-controlled valve.

[0013] Furthermore, a mud level gauge is installed on the top of the reactor body, and the mud level gauge is electrically connected to the AI ​​module of the intelligent control system. The AO module of the intelligent control system is electrically connected to the upper adjustable three-phase separator.

[0014] Furthermore, the water collection pipe (3) is equipped with an adjustable self-controlled valve, which is electrically connected to the AO module of the intelligent control system.

[0015] Furthermore, an outlet weir is constructed above the upper adjustable three-phase separator, and an outlet pipe is horizontally installed at the bottom of the outlet weir.

[0016] Furthermore, both the lower three-phase separator and the upper adjustable three-phase separator are connected to the biogas collection pipeline.

[0017] Furthermore, both the lower three-phase separator and the upper adjustable three-phase separator are double-layer structures, with the upper and lower layers arranged alternately and in an inverted V-shape with the opening facing downwards.

[0018] Furthermore, the outlet of the circulating pump branches into multiple water distribution pipes via a T-junction.

[0019] Furthermore, the water distribution pipe adopts a one-pipe-one-hole water distribution method, with only one water outlet at the end of each water distribution pipe.

[0020] Furthermore, the flow velocity at the outlet of each water distribution pipe is controlled to be greater than or equal to 2m / s, and the service area of ​​each outlet is 5-8㎡.

[0021] Beneficial effects

[0022] (1) The UASB reactor with adjustable sludge concentration of this utility model adopts an external circulation operation mode. On the one hand, when the concentration of organic matter in the influent fluctuates, the influent can be diluted to adjust the sludge concentration and reduce the risk of inhibition of anaerobic microorganisms. On the other hand, it increases the mixing intensity of wastewater and sludge particles and promotes the transfer of organic matter from the liquid phase to the surface of microorganisms.

[0023] (2) The present invention provides a UASB reactor with adjustable sludge concentration, wherein the water collection pipe is equipped with an adjustable self-controlled valve, which works in conjunction with the upper three-phase separable regulator to further improve the efficiency of adjusting sludge concentration.

[0024] (3) The UASB reactor with adjustable sludge concentration of this utility model introduces an intelligent control system. Based on the sludge concentration measured by the sludge level gauge, the circulating pump and the upper adjustable three-phase separator work together to achieve automatic and more precise adjustment of sludge concentration.

[0025] (4) The UASB reactor with adjustable sludge concentration of this utility model adopts a one-pipe-one-hole water distribution method to ensure that each water inlet point covers a specific area, achieves comprehensive and uniform water inlet, prevents water flow concentration, reduces short flow, and promotes full contact between wastewater and anaerobic sludge; the one-pipe-one-hole structure reduces mutual interference between water distribution holes, and even if individual holes are blocked, other holes can still operate normally, resulting in strong system stability; when the holes are blocked, they can be cleaned by backflushing or by cleaning specific pipes individually, which is convenient for maintenance and does not require shutting down the entire system.

[0026] In addition to the purposes, features, and effects described above, this utility model has other purposes, features, and effects. The present utility model will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present utility model;

[0028] Figure 2 This is a schematic diagram of the water distribution pipe structure according to an embodiment of the present utility model;

[0029] Figure 3 This is a simplified logic control diagram of the upper adjustable three-phase separator, the self-controlled valve, and the sludge concentration meter in an embodiment of this utility model.

[0030] The following are the labels in the schematic diagram: 1. Reactor body; 2. Lower three-phase separator; 3. Water collection pipe; 4. Upper adjustable three-phase separator; 5. Water outlet weir; 6. Sludge level gauge; 7. Biogas collection pipe; 8. Water outlet pipe; 9. Water inlet pipe; 10. Circulation pump; 11. Sludge discharge pump; 12. Water distribution pipe branch valve; 13. Water distribution pipe; 14. Sludge discharge pipe; 15. Guide rail; 16. Automatic control valve. Detailed Implementation

[0031] To enable those skilled in the art to better understand this technical solution, the technical solution of this utility model will be clearly and completely described below in conjunction with the accompanying drawings and embodiments.

[0032] The structures, proportions, and sizes illustrated in the accompanying drawings are merely for illustrative purposes and are not intended to limit the scope of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, provided they do not affect the effectiveness or purpose of this invention, should still fall within the scope of the disclosed technical content. Similarly, terms such as "upper" and "lower," "in" and "out" used in this specification are merely for clarity and not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.

[0033] To address the current problem of difficulty in effectively regulating sludge concentration, the basic idea of ​​this invention is to regulate sludge concentration by controlling the synergistic function of the circulating pump and the upper adjustable three-phase separator. Based on this, the introduction of a sludge level gauge and an intelligent control system enables automatic and more precise regulation of sludge concentration.

[0034] refer to Figures 1 to 3 As shown in the figure, an adjustable sludge concentration UASB reactor according to an embodiment of the present invention includes a reactor body 1 with a height of 12-15m and a height-to-diameter ratio of 3:1 to 4:1. A lower three-phase separator 2 is installed inside the reactor body 1. A water collection pipe 3 is installed above the lower three-phase separator 2. An upper adjustable three-phase separator 4 is installed above the water collection pipe 3. The upper adjustable three-phase separator 4 is movably connected to a guide rail 15, which is fixed to both sides of the reactor tank wall. The upper adjustable three-phase separator 4, as a whole, can be height-adjusted via the guide rail 15, which is driven by a motor.

[0035] The water collection pipe 3 and the water inlet pipe 9 are connected to the water inlet pipe of the circulating pump 10. The outlet of the circulating pump 10 is connected to the water distribution pipe 13 inside the reactor body. On the one hand, it dilutes the inlet water load, and on the other hand, it increases the mixing intensity of wastewater and sludge particles. The upward flow rate of the reactor can be flexibly adjusted by circulating the water outflow.

[0036] Microorganisms degrade organic matter in the reactor to produce biogas. The biogas pushes the mixed liquid to rise to the lower three-phase separator 2, where gas-solid-liquid separation occurs. The sludge falls back to the bottom of the reactor, and the mud-water mixture rises to the upper adjustable three-phase separator 4. The gas from the upper and lower three-phase separators is collected through the biogas collection pipe 7, and the effluent is discharged through the effluent weir 5 and the effluent pipe 8.

[0037] A sludge discharge pipe 14 is installed below the water distribution pipe 13. The sludge discharge pipe 14 is connected to the sludge discharge pump 11 and discharges the remaining sludge.

[0038] A sludge level gauge 6 is installed on the top of the reactor body 1 to measure the sludge concentration in the reaction zone.

[0039] The sludge level gauge 6 is electrically connected to the intelligent control system. The intelligent control system receives the sludge concentration signal measured by the sludge level gauge 6 through the AI ​​module, calculates the required height of the upper adjustable three-phase separator 4 based on this signal, and controls the upper adjustable three-phase separator 4 to slide a corresponding distance through the AO module, increasing the height of the settling zone, delaying the sludge settling time, preventing sludge loss, and increasing the sludge concentration. The intelligent control system can also control the return flow of the circulation pump 10 to replenish the sludge concentration in the reaction zone.

[0040] Under normal circumstances, the sludge concentration in the sludge bed of the reaction zone is 20-40 g / L. The lower three-phase separator 2 has intercepted most of the sludge. When the sludge concentration in the sludge bed of the reactor is less than 20 g / L, it indicates that most of the sludge has been lost. It is very likely that the separation efficiency of the lower three-phase separator 2 is insufficient. At this time, it is necessary to adjust the upper adjustable three-phase separator 4 to reduce the large amount of sludge loss and avoid the reduction of the treatment efficiency in the reactor.

[0041] When the sludge concentration count is less than 20 g / L, the signal is transmitted to the intelligent control system. The intelligent control system outputs an AO signal to adjust the stroke of the upper adjustable three-phase separator 4 motor, thereby driving the three-phase separator guide rail 15 to lower the separator height, increase the settling zone height, and delay the sludge settling time. The height is adjusted within a range of 0.5-1 m. Preferably, a gradual adjustment method is adopted, with each adjustment not exceeding 2 cm, and the effect is observed for 24-48 hours.

[0042] On the other hand, increasing the return flow of the circulating pump to replenish the sludge concentration in the reaction zone can be achieved. For example, an automatic control valve can be installed in the water collection pipe 3, electrically connected to the intelligent control system. When the sludge concentration count is less than 20 g / L, the opening of the automatic control valve on the water collection pipe 3 can be adjusted under the control of the intelligent control system to increase the return flow of the circulating pump; or other methods can be adopted to replenish the return flow of the sludge concentration in the reaction zone. Through the coordinated action of the sludge level gauge, the circulating pump, and the upper adjustable three-phase separator, the problem of sludge loss from the three-phase separator due to fluctuations in the incoming water load is reduced, eliminating the need for an anaerobic sedimentation tank.

[0043] The upflow velocity of the reactor is controlled to be less than 0.8 m / h to avoid loss of activated sludge due to excessive flow velocity.

[0044] The upper adjustable three-phase separator 4 is mainly adjustable in height, and can adjust the vertical position of the separator assembly, etc.

[0045] Traditional UASB systems lack a circulation pump, and the upward flow velocity depends entirely on the influent flow rate. If the influent flow rate fluctuates, the sludge bed may settle and compress due to insufficient flow velocity; if the flow velocity suddenly increases, sludge particles or flocs may be washed out. Using an external circulation pump can mitigate fluctuations in influent flow rate or concentration (such as intermittent industrial wastewater discharge), reduce the impact on the sludge bed, and maintain system stability.

[0046] An outlet weir 5 is constructed above the upper adjustable three-phase separator 4, and an outlet pipe 8 is horizontally installed at the bottom of the outlet weir 5 for collecting and discharging the clean water treated by the three-phase separator.

[0047] Both the lower three-phase separator 2 and the upper adjustable three-phase separator 4 are connected to the biogas collection pipeline 7 to collect the biogas produced by the anaerobic reaction, and collect it through the pipeline for subsequent processing.

[0048] Both the lower three-phase separator 2 and the upper adjustable three-phase separator 4 are double-layer structures with the upper and lower layers arranged alternately in an inverted V shape with the opening facing downwards. The inverted V-shaped structure design can effectively guide biogas to rise and collect it efficiently, and the sloping slope can control the flow rate, prevent sludge from entering the effluent area with the gas, and ensure that the sludge flows back smoothly to the bottom of the reactor.

[0049] In some embodiments, the outlet pipe of the circulating pump 10 branches into multiple distribution pipes 13 via a tee pipe. Each distribution pipe 13 uses a one-pipe-one-hole water distribution method, with only one outlet hole at the end of each distribution pipe 13. The flow velocity at the outlet hole of each distribution pipe 13 is controlled to be greater than or equal to 2 m / s, and the pipe diameter is ≥ DN50. Each outlet hole serves an area of ​​5-8 m², with the outlet facing downwards at 45°. Each distribution pipe 13 is connected to the main distribution pipe via branch pipes, and the branch pipe valves 12 achieve balanced flow regulation to ensure uniform water distribution.

[0050] Traditional UASB water distribution pipes use a perforated distribution method, which easily leads to buildup at the small holes of the perforated pipes, causing blockages. Excessive local flow velocity may cause short-circuiting (wastewater directly passes through the reaction zone without sufficient treatment), reducing reaction efficiency. Uneven water distribution can easily lead to local over-expansion or dead zones in the sludge bed, affecting the contact between sludge and wastewater.

[0051] The single-pipe, single-orifice water distribution method reduces the probability of orifice blockage. Each inlet point is independently controlled, avoiding short-circuit or dead zones and ensuring full contact between wastewater and sludge. If an individual pipe becomes blocked during operation, it does not affect the overall project operation. The blocked pipe is cleared individually, typically using high-pressure water flushing or acid washing. This water distribution method increases the uniformity of water distribution, reduces the frequency of blockage in the distribution pipe, and increases maintenance convenience.

[0052] The water distribution pipe 13 is 0.5 - 1 m away from the bottom of the reactor, which can further improve the uniformity of water distribution.

[0053] The water collection pipe 3 adopts a cross-shaped perforated pipe. The cross-shaped perforated pipe can effectively improve the pressure-bearing capacity of the pipe and reduce the water flow resistance at the same time. The sludge discharge pipe 14 also adopts a perforated pipe.

[0054] Compared with the traditional reactor, the technical solution of the present utility model can increase the removal rate of COD in sewage by 15% - 20%, reduce the sludge loss by more than 30%, enhance the anti-shock load capacity, and adapt to the COD fluctuation of 2000 - 10000 mg / L.

[0055] The above has schematically described the present utility model and its implementation manners. This description is not restrictive. What is shown in the drawings is only one of the implementation manners of the present utility model, and the actual structure is not limited thereto. If those of ordinary skill in the art are inspired by it and design similar structural manners to this technical solution without creative efforts without departing from the creative purpose of the present utility model, they shall fall within the protection scope of the present utility model.

Claims

1. A UASB reactor with adjustable sludge concentration, comprising a reactor body (1), characterized in that, The reactor body (1) is equipped with a lower three-phase separator (2), a water collection pipe (3) is installed above the lower three-phase separator (2), and an upper adjustable three-phase separator (4) is installed above the water collection pipe (3). The water collection pipe (3) and the water inlet pipe (9) are connected to the water inlet pipe of the circulating pump (10). The outlet of the circulating pump (10) is connected to the water distribution pipe (13) inside the reactor body. A sludge discharge pipe (14) is installed below the water distribution pipe (13). The sludge discharge pipe (14) is connected to the sludge discharge pump (11).

2. The UASB reactor according to claim 1, characterized in that, The water collection pipe (3) is equipped with an adjustable self-controlled valve (16).

3. The UASB reactor according to claim 1, characterized in that, A mud level gauge (6) is installed on the top of the reactor body (1). The mud level gauge (6) is electrically connected to the AI ​​module of the intelligent control system. The AO module of the intelligent control system is electrically connected to the upper adjustable three-phase separator.

4. The UASB reactor according to claim 3, characterized in that, The water collection pipe (3) is equipped with an adjustable self-control valve (16), which is electrically connected to the AO module of the intelligent control system.

5. The UASB reactor according to any one of claims 1 to 4, characterized in that, The upper adjustable three-phase separator (4) has an outlet weir (5) above it, and an outlet pipe (8) is horizontally installed at the bottom of the outlet weir (5).

6. The UASB reactor according to claim 5, characterized in that, Both the lower three-phase separator (2) and the upper adjustable three-phase separator (4) are connected to the biogas collection pipeline (7).

7. The UASB reactor according to claim 6, characterized in that, Both the lower three-phase separator (2) and the upper adjustable three-phase separator (4) are double-layer structures, with the upper and lower layers arranged alternately and in an inverted V-shape with the opening facing downwards.

8. The UASB reactor according to claim 1, characterized in that, The outlet of the circulating pump (10) branches into multiple water distribution pipes (13) through a three-way pipe.

9. The UASB reactor according to claim 8, characterized in that, The water distribution pipe (13) adopts a one-pipe-one-hole water distribution method, and each water distribution pipe (13) has only one outlet hole at the end.

10. The UASB reactor according to claim 9, characterized in that, The flow velocity of the outlet hole of each water distribution pipe (13) is controlled to be greater than or equal to 2m / s, and the service area of ​​each outlet hole is 5-8㎡.

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