Membrane tank backflow sludge degassing rectifier device for submerged MBR process and application method thereof

Abstract

The present application relates to sewage treatment technical field, specifically to a kind of submerged MBR process membrane pool backflow sludge degassing rectifier and application method.The device includes the air release component, vertical flow guide component and multiple-channel composite flow guide component sequentially arranged along the direction of mixed liquor flow;The air release component is multiple groups, and sequentially arranged in the backflow channel of MBR membrane pool along the direction of mixed liquor flow;The vertical flow guide component is vertically arranged in the end of the backflow channel, which includes parallel and downwardly inclined upper flow guide channel and lower flow guide channel, and both are arranged along the direction of mixed liquor flow;The multiple-channel composite flow guide component is arranged at the intersection of the backflow channel and backflow pump front pool.The application method uses the device to realize the uniform flow of mixed liquor to each backflow pump suction port.The present application can realize that the gas content of mixed liquor is less than 3%, and achieve degassing and rectification effect.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to a submerged MBR process membrane pool return sludge degassing and rectification device and an application method thereof. Background Art

[0002] The A2 / O+submerged membrane bioreactor (MBR) process has been widely used in the field of urban sewage treatment. Among them, the A2 / O, or AAO process, is a denitrification and phosphorus removal process based on the characteristics of microorganisms. It treats sewage through an anaerobic-anoxic-aerobic process. During operation, this process requires a return pump to continuously return the high-concentration mud-water mixture from the MBR membrane pool to the biochemical pool to maintain the concentration and activity of microorganisms in the biological pool. However, the membrane components of the submerged MBR process require large-volume aeration scrubbing to maintain membrane flux. This process causes the high-concentration activated sludge in the membrane pool to closely combine with the dense bubbles generated by aeration, causing a large amount of gas to be entrained in the return mixture and increasing the dissolved oxygen concentration. In addition, during the operation of the return pump, the strong shearing effect of the impeller on the highly aerated activated sludge flocs will further break up the sludge flocs and bubbles, prompting the release of dissolved oxygen to form an oxygen-rich environment. When this high-dissolved oxygen mixed liquid flows back to the aerobic zone of the biochemical pool, it will significantly increase the dissolved oxygen level in the system, destroying the anoxic / anaerobic environment required for denitrification and phosphorus removal, and ultimately leading to a decrease in the efficiency of biological denitrification and phosphorus removal.

[0003] In addition, the existing MBR membrane pool mixed liquid return all uses channels to enter the return pump forebay. This process has a large flow rate and a short residence time, resulting in the formation of a three-phase, three-dimensional turbulent vortex of air-water-mud in the return pump forebay. The water suction conditions of the return pump are extremely complex, which can easily cause adverse phenomena such as cavitation of the return pump, resulting in reduced water delivery efficiency. In severe cases, it can cause damage to the impeller or even the return pump.

[0004] Currently, there is a lack of degassing and rectifying devices suitable for return sludge from submerged MBR membrane tanks, both domestically and internationally. There is an urgent need to develop a degassing and rectifying device and application method for return sludge from submerged MBR membrane tanks. On the one hand, this device can be used to degas the return mixed liquor discharged from the submerged MBR membrane tanks to reduce the adverse effects of high gas content and high dissolved oxygen content on nitrogen and phosphorus removal in the biochemical tank. On the other hand, this device can be used to prevent cavitation in the return pump, eliminate vibration during operation, and prevent damage to the return pump. Summary of the Invention

[0005] The present invention aims to provide a degassing and rectifying device for return sludge in a submerged MBR process membrane pool and an application method thereof. The specific technical scheme is as follows:

[0006] In a first aspect, the present invention provides a submerged MBR process membrane pool return sludge degassing and rectification device, which includes an air release component, a vertical flow guide component and a multi-channel composite flow guide component arranged in sequence along the flow direction of the mixed liquid;

[0007] The number of the air release components is multiple groups, and they are sequentially arranged in the reflux channel of the MBR membrane pool along the flow direction of the mixed liquid; a first installation gap is connected or set between each two adjacent groups of the air release components; each group of the air release components includes a first frame and an air release component; the number of the air release components is multiple, and they are arranged in rows and intervals in the first frame along the flow direction of the mixed liquid; the first frame is arranged in the reflux channel; a second installation gap is set between each two adjacent rows of the air release components; the air release components of two adjacent rows are staggered; a third installation gap is set between two adjacent air release components in each row; the air release component is an integrally formed V-shaped structure, and its opening direction is the same as the flow direction of the mixed liquid;

[0008] The vertical flow guide assembly is vertically arranged at the end of the reflux channel, and includes an upper flow guide channel and a lower flow guide channel that are arranged in parallel and tilted downward, and both are arranged along the flow direction of the mixed liquid;

[0009] The multi-channel composite diversion component is arranged at the intersection of the reflux channel and the reflux pump forepool.

[0010] Optionally, the spacing of the first installation gap is 0.2 to 0.5 times the width of the reflux channel.

[0011] Optionally, the spacing of the second installation gap is 0.01 to 0.3 times the width of the reflux channel; the spacing of the third installation gap is 0.01 to 0.2 times the width of the reflux channel.

[0012] Optionally, the angle of the V-shaped structure is 30° to 75°;

[0013] The V-shaped structure includes an integrally formed first connecting plate and a second connecting plate; the length of the first connecting plate and the length of the second connecting plate are both 250~450mm; the top of the first connecting plate and the top of the second connecting plate are both connected to the top of the first frame, and the bottom of the first connecting plate and the bottom of the second connecting plate are both connected to the bottom of the first frame.

[0014] Optionally, the first frame includes a first side panel, a second side panel, a first top panel, and a first bottom panel; the first side panel and the second side panel are arranged opposite to each other and are respectively connected to the first side wall and the second side wall on both sides of the reflux channel; the first top panel is arranged on the top of the first side panel and the second side panel and is tilted downward; the inclination angle of the first top panel is 3° to 15°; the projection length of the first top panel at the bottom of the reflux channel is 1.0 to 2.5 times the width of the reflux channel; the highest point of the first top panel is located 0.1 m below the design water depth;

[0015] The first bottom plate is arranged on the bottom ends of the first side plate and the second side plate; the length of the first bottom plate is 1.0 to 2.5 times the width of the reflux channel;

[0016] The length of the first side plate and the length of the second side plate are both 1.0 to 2.5 times the width of the reflux channel.

[0017] Optionally, the vertical air guide assembly includes a second frame and an intermediate plate;

[0018] The second frame includes a third side plate, a fourth side plate, a second top plate, and a second bottom plate; the third side plate and the fourth side plate are arranged opposite to each other and are respectively connected to the first side wall and the second side wall on both sides of the end of the reflux channel;

[0019] The second top plate is arranged on the top of the third side plate and the fourth side plate and is tilted downward; the tilt angle of the second top plate is 5° to 25°; the projection length of the second top plate at the bottom of the reflux channel is 0.5 to 1.5 times the width of the reflux channel; the highest point of the second top plate is located 250 to 1000 mm below the design water depth;

[0020] The second bottom plate is horizontally arranged on the bottom ends of the third side plate and the fourth side plate; the length of the second bottom plate is 1.0 to 2.5 times the width of the reflux channel;

[0021] The middle plate is disposed between the second top plate and the second bottom plate and is arranged parallel to the second top plate; both ends of the middle plate are connected to the third side plate and the fourth side plate respectively; the projected length of the middle plate at the bottom of the reflux channel is 0.5 to 1.5 times the width of the reflux channel; the distance between the middle plate and the second bottom plate is 1 / 3 to 2 / 3 of the height of the vertical flow guide assembly;

[0022] The middle plate, the second top plate, the third side plate and the fourth side plate form the upper guide channel; the middle plate, the second bottom plate, the third side plate and the fourth side plate form the lower guide channel.

[0023] Optionally, the multi-channel composite guide assembly includes a straight section guide plate, a double-fold guide plate and a triple-fold guide plate arranged at intervals along the mixed liquid flow section; the straight section guide plate and the double-fold guide plate are both connected to the No. 1 side wall of the reflux channel (such as fixedly connected to the No. 1 side wall through a guide rod); the triple-fold guide plate is connected to the No. 2 side wall of the reflux channel (such as fixedly connected to the No. 2 side wall through a guide rod); a first flow channel d1 is formed between the straight section guide plate and its adjacent No. 1 side wall, a second flow channel d2 is formed between the straight section guide plate and the double-fold guide plate, a third flow channel d3 is formed between the double-fold guide plate and the triple-fold guide plate, and a fourth flow channel d4 is formed between the triple-fold guide plate and its adjacent No. 2 side wall.

[0024] Optionally, the included angle between the straight section guide plate and the adjacent No. 1 side wall is 5° to 15°; the length of the straight section guide plate is 0.5 to 1.5 times the width of the return channel; the height of the straight section guide plate is the design water depth minus 200 to 500 mm; both ends of the straight section guide plate include a first V-shaped sharp angle structure; the included angle of the first V-shaped sharp angle structure is 30° to 60°; and the length of both sides of the first V-shaped sharp angle structure is 50 to 150 mm.

[0025] The double-fold guide plate includes a first straight guide plate and a second straight guide plate connected integrally; the second straight guide plate and the first straight guide plate are arranged in sequence along the flow direction of the mixed liquid; the angle between the first straight guide plate and the first side wall is 5° to 35°; the length of the first straight guide plate is 0.2 to 0.5 times the width of the return channel; the height of the first straight guide plate is the design water depth minus 200 to 500 mm;

[0026] The included angle between the second straight guide plate and the first straight guide plate is 150° to 175°; the length of the second straight guide plate is 0.2 to 0.6 times the width of the return channel; the height of the second straight guide plate is the design water depth minus 200 to 500 mm;

[0027] The first straight guide plate includes a second V-shaped sharp angle structure at one end away from the second straight guide plate; the second straight guide plate includes a third V-shaped sharp angle structure at one end away from the first straight guide plate; the included angle between the second V-shaped sharp angle structure and the third V-shaped sharp angle structure is 30° to 60°; and the length of both sides of the second V-shaped sharp angle structure and the third V-shaped sharp angle structure is 50 to 150 mm;

[0028] The three-fold guide plate includes a third straight guide plate, a fourth straight guide plate and a fifth straight guide plate that are integrally connected; the fifth straight guide plate, the fourth straight guide plate and the third straight guide plate are arranged in sequence along the flow direction of the mixed liquid; the angle between the fifth straight guide plate and the first side wall is 0°~10°; the angle between the fourth straight guide plate and the fifth straight guide plate is 135°~175°; the angle between the third straight guide plate and the fourth straight guide plate is The angle of the fifth straight guide plate is 120° to 175°; the length of the fifth straight guide plate and the length of the third straight guide plate are both 0.1 to 0.6 times the width of the return channel; the height of the fifth straight guide plate and the height of the third straight guide plate are both the design water depth minus 200 to 500 mm; the length of the fourth straight guide plate is 0.1 to 1.0 times the width of the return channel; the height of the fourth straight guide plate is both the design water depth minus 200 to 600 mm;

[0029] The end of the third straight guide plate away from the fourth straight guide plate includes a fourth V-shaped sharp-angle structure; the end of the fifth straight guide plate away from the fourth straight guide plate includes a fifth V-shaped sharp-angle structure; the angles between the fourth V-shaped sharp-angle structure and the fifth V-shaped sharp-angle structure are both 30°~60°; the lengths of both side edges of the fourth V-shaped sharp-angle structure and the fifth V-shaped sharp-angle structure are both 50~150mm.

[0030] In a second aspect, the present invention provides an application method of the submerged MBR process membrane pool return sludge degassing and rectification device, which includes using the Navier-Stokes equations and the k-omega SST turbulence model as the control mechanism, using the return pump inflow uniformity as the control parameter, and using CFD multiphase transient simulation results to determine the length range, height range, angle range, and ratio of d1:d2:d3:d4 of the multi-channel composite guide assembly with a return pump inflow uniformity of less than 10% for return channels and return pump forebays of MBR membrane pools of different sizes;

[0031] Among them, the ratio of d1:d2:d3:d4 is 1~3:1~2:1:1.

[0032] Optionally, the reflux pump inflow uniformity is obtained using the following formula:

[0033] ;

[0034] in, Indicates the uniformity of the return pump inflow at a section 0.5m in front of the return pump suction port; N It represents the value of the cross-section width along the reflux pump forebay divided into equal parts. N The value is twice the number of reflux pumps; i The value range is 1 toN ; It represents the average flow velocity at the section 0.5 m before the water inlet of the return pump. Its value is obtained by performing surface integration on the velocity values ​​of all calculation nodes on the section obtained from the CFD multiphase transient simulation results. Indicates the i The average flow velocity of a subsection located 0.5 m before the water inlet of the return pump is obtained by performing surface integration on the velocity values ​​of all calculation nodes on the subsection obtained from the CFD multiphase transient simulation results.

[0035] The application of the technical solution of the present invention has at least the following beneficial effects:

[0036] (1) The submerged MBR process membrane pool return sludge degassing and rectification device provided by the present invention is used, on the one hand, to degas the return mixed liquid discharged from the submerged MBR process membrane pool, so as to reduce the adverse effects of the high gas content and high dissolved oxygen content of the return mixed liquid on the denitrification and phosphorus removal of the biochemical pool; on the other hand, it is used to prevent cavitation of the return pump, eliminate vibration during the operation of the return pump, and prevent damage to the return pump. Specifically:

[0037] The reflux mixture (hereinafter referred to as the mixed liquid) of disordered mixing of gas, water and mud with high gas content (such as gas content greater than 8%) first enters the air release component. When it flows to the air release components of the V-shaped structure, the mixed liquid begins to separate from the tip of the V-shaped structure of each air release component and moves along the two sides of the V-shaped structure to form separated flow beams. Since the air release components in the two adjacent rows are staggered, these flow beams that have just been separated converge in the open gap of the V-shaped structure of each air release component in the previous row, and immediately touch the tip of the V-shaped structure of each air release component in the next row, and separate again. Reciprocating, forming a diamond-shaped network flow pattern, turbulent shear degassing occurs; at the same time, during the separation and merging process of the mixed liquid, a flow velocity difference is generated between the upstream and downstream surfaces of the V-shaped structure of each air release component, thereby forming micro-vortices on the downstream surface of the V-shaped structure of each air release component (i.e., the V-shaped structure), thereby enhancing shear degassing; therefore, the present invention achieves the purpose of degassing by combining the turbulent shear degassing of the air release component with the enhanced degassing of the micro-vortex, thereby reducing the gas content of the mixed liquid to less than 3%, thereby effectively reducing the adverse effects of the high gas content and high dissolved oxygen content of the reflux mixed liquid on the denitrification and phosphorus removal of the biochemical pool, and preventing cavitation of the reflux pump;

[0038] The degassed mixed liquid enters the vertical flow guide assembly. When it flows through the upper and lower guide channels, which are arranged in parallel and tilted downward, the turbulent mixed liquid changes its original flow direction under the action of the Coanda effect. It changes from a diamond-shaped network flow rich in micro-vortices to a parallel flow along the upper and lower guide channels, achieving vertical rectification and forming a steady flow with a downward tilt and basically smooth and straight streamlines. This avoids the unfavorable water suction condition where the water suction elevation of the return pump is lower than the water intake elevation.

[0039] Subsequently, the mixed liquid enters the multi-channel composite diversion assembly, and its velocity components flow evenly to the water inlets of each reflux pump under the action of the Coanda effect, avoiding the strong vortex impact on the reflux pump impeller caused by uneven inflow and preventing damage to the reflux pump.

[0040] (2) The submerged MBR process membrane pool return sludge degassing and rectification device provided by the present invention has no valves or pipes, no electromechanical transmission components, high reliability, and low maintenance and overhaul workload.

[0041] (3) The application method of the submerged MBR process membrane pool return sludge degassing and rectifying device provided by the present invention can determine the length range, height range, angle range and ratio d1:d2:d3:d4 of the multi-channel composite guide assembly with a return pump inflow uniformity of less than 10%, ensure that the mixed liquid flows evenly to each return pump suction port, avoid the strong vortex caused by uneven inflow to impact the return pump impeller, and prevent the return pump from being damaged.

[0042] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0044] Figure 1 This is a schematic top view of the structure after a degassing and rectifying device is installed in the reflux channel and at the intersection of the reflux channel and the reflux pump forebay in the embodiment;

[0045] Figure 2 is a schematic top view of the air release assembly in the embodiment;

[0046] Figure 3 1 is a schematic top view of the vertical flow guide assembly in the embodiment;

[0047] Figure 4 yes Figure 3 Cross-section in the WW direction;

[0048] Figure 5 1 is a schematic top view of the multi-channel composite flow guide assembly in an embodiment;

[0049] Figure 6 It is a flow velocity vector diagram of a cross section taken along the center of all reflux pumps (abbreviated as pump 1, pump 2 and pump 3 in the figure) in a comparative example in which no degassing and rectifying device is installed at the reflux channel and the intersection of the reflux channel and the reflux pump forebay;

[0050] Figure 7 This is a flow velocity vector diagram of a cross section taken along the center of all reflux pumps (abbreviated as pump 1, pump 2, and pump 3 in the figure) after a degassing and rectifying device is installed in the reflux channel and at the intersection of the reflux channel and the reflux pump forebay in the embodiment;

[0051] Figure 8 It is a flow velocity vector diagram of a longitudinal section taken along the center of reflux pump 1 (abbreviated as pump 1 in the figure) in a comparative example in which no degassing and rectifying device is installed at the reflux channel and the intersection of the reflux channel and the reflux pump forebay;

[0052] Figure 9 This is a flow velocity vector diagram of a longitudinal section taken along the center of a reflux pump 1 (abbreviated as pump 1 in the figure) after a degassing and rectifying device is installed in the reflux channel and at the intersection of the reflux channel and the reflux pump forebay in the embodiment;

[0053] Figure 10 It is a flow velocity vector diagram of a longitudinal section taken along the center of reflux pump 2 (abbreviated as pump 2 in the figure) in a comparative example in which no degassing and rectifying device is installed at the reflux channel and the intersection of the reflux channel and the reflux pump forebay;

[0054] Figure 11 This is a flow velocity vector diagram of a longitudinal section taken along the center of the reflux pump 2 (abbreviated as pump 2 in the figure) after a degassing and rectifying device is installed in the reflux channel and at the intersection of the reflux channel and the reflux pump forebay in the embodiment;

[0055] Figure 12 It is a flow velocity vector diagram of a longitudinal section taken along the center of the reflux pump 3 (abbreviated as pump 3 in the figure) in the comparative example where no degassing and rectifying device is installed at the reflux channel and the intersection of the reflux channel and the reflux pump forebay;

[0056] Figure 13 This is a flow velocity vector diagram of a longitudinal section taken along the center of the reflux pump 3 (abbreviated as pump 3 in the figure) after a degassing and rectifying device is installed in the reflux channel and at the intersection of the reflux channel and the reflux pump forebay in the embodiment;

[0057] Among them, 1. Air release assembly, 1.1. First frame, 1.1.1. First side panel, 1.1.2. Second side panel, 1.2. Air release component, 1.2.1. First connecting plate, 1.2.2. Second connecting plate, 2. Vertical guide assembly, 2.1. Middle plate, 2.2. Second top plate, 2.3. Second bottom plate, 2.4. Third side panel, 2.5. Fourth side panel, 3. Multi-channel composite guide assembly, 3.1. Straight guide panel, 3.2. Double-fold guide panel, 3.2.1. First straight guide panel, 3.2.2. Second straight guide panel, 3.3. Triple-fold guide panel, 3.3.1. Third straight guide panel, 3.3.2. Fourth straight guide panel, 3.3.3. Fifth straight guide panel, A. Return channel, A1. Side wall No. 1, A2. Side wall No. 2, B. Return pump front pool. DETAILED DESCRIPTION

[0058] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention are within the scope of protection of the present invention.

[0059] Example:

[0060] See also Figures 1 to 5 The submerged MBR process membrane pool return sludge degassing and rectification device includes an air release component 1, a vertical flow guide component 2 and a multi-channel composite flow guide component 3 which are sequentially arranged along the flow direction of the mixed liquid;

[0061] The number of the air release components 1 is multiple groups (specifically 2 groups), and they are sequentially arranged in the reflux channel A (width of 1.9m) of the MBR membrane pool along the flow direction of the mixed liquid (that is, the first group of air release components 1 and the second group of air release components 1 are sequentially arranged in the reflux channel A of the MBR membrane pool); a first installation gap is connected or set between each two adjacent groups of the air release components 1; each group of the air release components 1 includes a first frame 1.1 and an air release component 1.2; the number of the air release components 1.2 is multiple, and they are arranged in rows and intervals in the first frame 1.1 along the flow direction of the mixed liquid; the first frame 1.1 is arranged in the reflux channel A; a second installation gap is set between each two adjacent rows of the air release components 1.2; the air release components 1.2 in two adjacent rows are staggered; a third installation gap is set between two adjacent air release components 1.2 in each row; the air release component 1.2 is an integrally formed V-shaped structure, and its opening direction is the same as the flow direction of the mixed liquid;

[0062] The vertical flow guide assembly 2 is vertically arranged at the end of the reflux channel A, and includes an upper flow guide channel and a lower flow guide channel that are arranged in parallel and tilted downward, and both are arranged along the flow direction of the mixed liquid;

[0063] The multi-channel composite diversion component 3 is arranged at the intersection of the reflux channel A and the reflux pump forebay B (with a width of 7.3m) (the reflux channel A is connected to the reflux pump forebay B).

[0064] The second group of air release components 1, the vertical air guide component 2 and the multi-channel composite air guide component 3 are sequentially connected without any gap.

[0065] The spacing of the first installation gap is 0.2 to 0.5 times the width of the return channel A (specifically 0.2 times, that is, the spacing between the first group of air release components 1 and the second group of air release components 1 is 0.2 times the width of the return channel A).

[0066] The spacing of the second installation gap is 0.01 to 0.3 times (specifically 0.2 times) the width of the return channel A; the spacing of the third installation gap is 0.01 to 0.2 times (specifically 0.084 times) the width of the return channel A.

[0067] The included angle of the V-shaped structure is 30° to 75° (specifically 60°).

[0068] The V-shaped structure includes a first connecting plate 1.2.1 (specifically a corrosion-resistant plate) and a second connecting plate 1.2.2 (specifically a corrosion-resistant plate) that are integrally formed (such as bending or stamping); the length of the first connecting plate 1.2.1 and the length of the second connecting plate 1.2.2 are both 250~450mm (specifically 300mm); the top of the first connecting plate 1.2.1 and the top of the second connecting plate 1.2.2 are both connected to the top of the first frame 1.1 (i.e., the first top plate), and the bottom of the first connecting plate 1.2.1 and the bottom of the second connecting plate 1.2.2 are both connected to the bottom of the first frame 1.1 (i.e., the first bottom plate).

[0069] The first frame 1.1 includes a first side panel 1.1.1, a second side panel 1.1.2, a first top panel, and a first bottom panel. The first side panel 1.1.1 and the second side panel 1.1.2 are disposed opposite each other and are respectively connected to the first side wall A1 and the second side wall A2 on both sides of the reflux channel A. The first top panel is disposed on the tops of the first side panel 1.1.1 and the second side panel 1.1.2 and is tilted downward. The inclination angle of the first top panel is 3° to 15° (specifically 5°). The projected length of the first top panel at the bottom of the reflux channel A is 1.0 to 2.5 times (specifically 1.0 times) the width of the reflux channel A. The highest point of the first top panel is located 0.1 m below the design water depth.

[0070] The first bottom plate is arranged on the bottom ends of the first side plate 1.1.1 and the second side plate 1.1.2; the length of the first bottom plate is 1.0 to 2.5 times (specifically 1.0 times) the width of the reflux channel A;

[0071] The length of the first side plate 1.1.1 and the length of the second side plate 1.1.2 are both 1.0 to 2.5 times (specifically 1.0 times) the width of the reflux channel A.

[0072] The vertical air guide assembly 2 includes a second frame and an intermediate plate 2.1;

[0073] The second frame includes a third side panel 2.4, a fourth side panel 2.5, a second top panel 2.2, and a second bottom panel 2.3; the third side panel 2.4 and the fourth side panel 2.5 are disposed opposite each other and are respectively connected to the first side wall A1 and the second side wall A2 on both sides of the end of the reflux channel A;

[0074] The second top plate 2.2 is disposed on top of the third side plate 2.4 and the fourth side plate 2.5 and is tilted downward. The tilt angle of the second top plate 2.2 is 5° to 25° (specifically 5°). The projected length of the second top plate 2.2 at the bottom of the reflux channel A is 0.5 to 1.5 times (specifically 1.0 times) the width of the reflux channel A. The highest point of the second top plate 2.2 is located 250 to 1000 mm below the design water depth (specifically 300 mm below the design water depth).

[0075] The second bottom plate 2.3 is horizontally arranged on the bottom ends of the third side plate 2.4 and the fourth side plate 2.5; the length of the second bottom plate 2.3 is 1.0 to 2.5 times (specifically 1.0 times) the width of the reflux channel A;

[0076] The intermediate plate 2.1 is arranged between the second top plate 2.2 and the second bottom plate 2.3, and is arranged parallel to the second top plate 2.2; the two ends of the intermediate plate 2.1 are respectively connected to the third side plate and the fourth side plate 2.5 described in 2.4; the projected length of the intermediate plate 2.1 at the bottom of the return channel A is 0.5 to 1.5 times (specifically 1.0 times) the width of the return channel A; the distance between the intermediate plate 2.1 and the second bottom plate 2.3 is 1 / 3 to 2 / 3 (specifically 1 / 3) the height of the vertical flow guide assembly 2; the height of the vertical flow guide assembly 2 is the design water depth minus the distance from the highest point of the second top plate 2.2 to the water surface, which is 2.875m.

[0077] The middle plate 2.1, the second top plate 2.2, the third side plate 2.4 and the fourth side plate 2.5 form the upper guide channel; the middle plate 2.1, the second bottom plate 2.3, the third side plate 2.4 and the fourth side plate 2.5 form the lower guide channel.

[0078] The multi-channel composite guide assembly 3 includes a straight guide plate 3.1 (thickness of 50-260 mm, specifically 50 mm), a double-fold guide plate 3.2 (thickness of 50-260 mm, specifically 50 mm), and a triple-fold guide plate 3.3 (thickness of 50-260 mm, specifically 50 mm) arranged at intervals along the mixed liquid flow section. The straight guide plate 3.1 and the double-fold guide plate 3.2 are both connected to the first side wall A1 of the return channel A (e.g., fixedly connected to the first side wall A1 via a guide rod). The three-fold guide plate 3.3 is connected to the No. 2 side wall A2 of the return channel A (such as being fixedly connected to the No. 2 side wall A2 through a guide rod); a first flow channel d1 is formed between the straight section guide plate 3.1 and the adjacent No. 1 side wall A1, a second flow channel d2 is formed between the straight section guide plate 3.1 and the double-fold guide plate 3.2, a third flow channel d3 is formed between the double-fold guide plate 3.2 and the three-fold guide plate 3.3, and a fourth flow channel d4 is formed between the three-fold guide plate 3.3 and the adjacent No. 2 side wall A2.

[0079] The straight section guide plate 3.1 (specifically, a guide plate made of corrosion-resistant material) forms an angle of 5° to 15° with the first side wall A1; the length of the straight section guide plate 3.1 is 0.5 to 1.5 times the width of the return channel A; the height of the straight section guide plate 3.1 is the design water depth minus 200 to 500 mm; both ends of the straight section guide plate 3.1 include a first V-shaped sharp angle structure; the angle of the first V-shaped sharp angle structure is 30° to 60°; and the length of both sides of the first V-shaped sharp angle structure is 50 to 150 mm.

[0080] The double-fold guide plate 3.2 comprises an integrally connected first straight guide plate 3.2.1 (specifically, a guide plate made of corrosion-resistant material) and a second straight guide plate 3.2.2 (specifically, a guide plate made of corrosion-resistant material). The second straight guide plate 3.2.2 and the first straight guide plate 3.2.1 are arranged sequentially along the flow direction of the mixed liquid. The angle between the first straight guide plate 3.2.1 and the first side wall A1 is 5° to 35°. The length of the first straight guide plate 3.2.1 is 0.2 to 0.5 times the width of the return channel A. The height of the first straight guide plate 3.2.1 is the design water depth minus 200 to 500 mm.

[0081] The included angle between the second straight guide plate 3.2.2 and the first straight guide plate 3.2.1 is 150° to 175°; the length of the second straight guide plate 3.2.2 is 0.2 to 0.6 times the width of the return channel A; the height of the second straight guide plate 3.2.2 is the design water depth minus 200 to 500 mm;

[0082] The end of the first straight guide plate 3.2.1 away from the second straight guide plate 3.2.2 includes a second V-shaped sharp angle structure; the end of the second straight guide plate 3.2.2 away from the first straight guide plate 3.2.1 includes a third V-shaped sharp angle structure; the angle between the second V-shaped sharp angle structure and the third V-shaped sharp angle structure is 30° to 60°; the length of the sides of the second V-shaped sharp angle structure and the third V-shaped sharp angle structure is 50 to 150 mm;

[0083] The three-fold guide plate 3.3 includes an integrally connected third straight guide plate 3.3.1 (specifically a guide plate made of corrosion-resistant material), a fourth straight guide plate 3.3.2 (specifically a guide plate made of corrosion-resistant material) and a fifth straight guide plate 3.3.3 (specifically a guide plate made of corrosion-resistant material); the fifth straight guide plate 3.3.3, the fourth straight guide plate 3.3.2 and the third straight guide plate 3.3.1 are arranged in sequence along the flow direction of the mixed liquid; the angle between the fifth straight guide plate 3.3.3 and the first side wall A1 is 0°~10°; the angle between the fourth straight guide plate 3.3.2 and the fifth straight guide plate 3.3.3 is 135°~17 5°; the included angle between the third straight guide plate 3.3.1 and the fourth straight guide plate 3.3.2 is 120°-175°; the length of the fifth straight guide plate 3.3.3 and the length of the third straight guide plate 3.3.1 are both 0.1-0.6 times the width of the return channel A; the height of the fifth straight guide plate 3.3.3 and the height of the third straight guide plate 3.3.1 are both the design water depth minus 200-500mm; the length of the fourth straight guide plate 3.3.2 is 0.1-1.0 times the width of the return channel A; the height of the fourth straight guide plate 3.3.2 is both the design water depth minus 200-600mm;

[0084] The end of the third straight guide plate 3.3.1 away from the fourth straight guide plate 3.3.2 includes a fourth V-shaped sharp-angle structure; the end of the fifth straight guide plate 3.3.3 away from the fourth straight guide plate 3.3.2 includes a fifth V-shaped sharp-angle structure; the angle between the fourth V-shaped sharp-angle structure and the fifth V-shaped sharp-angle structure is 30°~60°; the length of the two side edges of the fourth V-shaped sharp-angle structure and the fifth V-shaped sharp-angle structure is 50~150mm.

[0085] The application method of the submerged MBR process membrane pool return sludge degassing and rectifying device includes using the Navier-Stokes equations and the k-omega SST turbulence model as a control mechanism, using the return pump inflow uniformity as a control parameter, and using CFD multiphase transient simulation results to determine the length range, height range, angle range, and ratio of d1:d2:d3:d4 of the multi-channel composite guide component 3 when the return pump inflow uniformity is less than 10% for the return pump inflow uniformity of less than 10% for the return channel A and the return pump forebay B of MBR membrane pools of different sizes;

[0086] Among them, the ratio of d1:d2:d3:d4 is 1~3:1~2:1:1.

[0087] The reflux pump inflow uniformity is obtained using the following formula:

[0088] ;

[0089] in, Indicates the uniformity of the return pump inflow at a section 0.5m in front of the return pump suction port; N It represents the value of the cross-section width of the reflux pump forebay B divided into equal parts. N The value is twice the number of reflux pumps; i The value range is 1 to N ; It represents the average flow velocity at the section 0.5 m before the water inlet of the return pump. Its value is obtained by performing surface integration on the velocity values ​​of all calculation nodes on the section obtained from the CFD multiphase transient simulation results. Indicates the i The average flow velocity of a subsection located 0.5 m before the water inlet of the return pump is obtained by performing surface integration on the velocity values ​​of all calculation nodes on the subsection obtained from the CFD multiphase transient simulation results.

[0090] A submerged MBR process was selected, and its operating parameters are shown in Table 1 (in Table 1, "d" represents day).

[0091] Table 1 Immersed MBR process operating parameters

[0092]

[0093] From the data in Table 1, we know that in this embodiment, the number of reflux pumps is 3 (the 3 reflux pumps are installed at intervals on the outlet side of the reflux pump forebay B). N The value is 6.

[0094] In this embodiment, based on the data in Table 1, the CFD multiphase transient simulation results in the application method are used to determine the length range, height range, angle range, and ratio of d1:d2:d3:d4 of the multi-channel composite flow guide component 3 for a reflux pump inflow uniformity of less than 10%. The specific simulation results are as follows:

[0095] Simulation result 1:

[0096] (1) The length of the straight section guide plate 3.1 is 0.6 times the width of the return channel A, and its height is the design water depth minus 200. The angle between it and the first side wall A1 is 5°; the angle of the first V-shaped sharp angle structure is 60°, and the length of both sides of it is 60 mm;

[0097] (2) The length of the second straight guide plate 3.2.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first straight guide plate 3.2.1 is 165°; the angle of the third V-shaped sharp angle structure is 60°, and the length of both sides of it is 60 mm;

[0098] The length of the first straight deflector 3.2.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the first side wall A1 is 25°. The angle of the second V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0099] (3) The length of the fifth straight guide plate 3.3.3 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first side wall A1 is 6°; the angle of the fifth V-shaped sharp angle structure is 60°, and the length of its two sides is 60 mm;

[0100] The length of the fourth straight guide plate 3.3.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the fifth straight guide plate 3.3.3 is 152°.

[0101] The length of the third straight deflector 3.3.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the fourth straight deflector 3.3.2 is 151°. The angle of the third V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0102] d1:d2:d3:d4=1:1:1:1;

[0103] The inflow uniformity of the reflux pump is 8.2%.

[0104] Simulation result 2:

[0105] (1) The length of the straight section guide plate 3.1 is 0.6 times the width of the return channel A, and its height is the design water depth minus 200. The angle between it and the first side wall A1 is 10°; the angle of the first V-shaped sharp angle structure is 60°, and the length of both sides of it is 60mm;

[0106] (2) The length of the second straight guide plate 3.2.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first straight guide plate 3.2.1 is 165°; the angle of the third V-shaped sharp angle structure is 60°, and the length of both sides of it is 60 mm;

[0107] The length of the first straight deflector 3.2.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the first side wall A1 is 25°. The angle of the second V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0108] (3) The length of the fifth straight guide plate 3.3.3 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first side wall A1 is 6°; the angle of the fifth V-shaped sharp angle structure is 60°, and the length of its two sides is 60 mm;

[0109] The length of the fourth straight guide plate 3.3.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the fifth straight guide plate 3.3.3 is 152°.

[0110] The length of the third straight deflector 3.3.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the fourth straight deflector 3.3.2 is 151°. The angle of the third V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0111] d1:d2:d3:d4=1:1:1:1;

[0112] The reflux pump inflow uniformity is 5.5%.

[0113] Simulation result three:

[0114] (1) The length of the straight section guide plate 3.1 is 0.6 times the width of the return channel A, and its height is the design water depth minus 200. The angle between it and the first side wall A1 is 10°; the angle of the first V-shaped sharp angle structure is 60°, and the length of both sides of it is 60mm;

[0115] (2) The length of the second straight guide plate 3.2.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first straight guide plate 3.2.1 is 165°; the angle of the third V-shaped sharp angle structure is 60°, and the length of both sides of it is 60 mm;

[0116] The length of the first straight deflector 3.2.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the first sidewall A1 is 32°. The angle of the second V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0117] (3) The length of the fifth straight guide plate 3.3.3 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first side wall A1 is 6°; the angle of the fifth V-shaped sharp angle structure is 60°, and the length of its two sides is 60 mm;

[0118] The length of the fourth straight guide plate 3.3.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the fifth straight guide plate 3.3.3 is 152°.

[0119] The length of the third straight deflector 3.3.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the fourth straight deflector 3.3.2 is 151°. The angle of the third V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0120] d1:d2:d3:d4=1:1:1:1;

[0121] The reflux pump inflow uniformity is 4.1%.

[0122] Simulation result 4:

[0123] (1) The length of the straight section guide plate 3.1 is 0.6 times the width of the return channel A, and its height is the design water depth minus 200. The angle between it and the first side wall A1 is 10°; the angle of the first V-shaped sharp angle structure is 60°, and the length of both sides of it is 60mm;

[0124] (2) The length of the second straight guide plate 3.2.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first straight guide plate 3.2.1 is 165°; the angle of the third V-shaped sharp angle structure is 60°, and the length of both sides of it is 60 mm;

[0125] The length of the first straight deflector 3.2.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the first sidewall A1 is 32°. The angle of the second V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0126] (3) The length of the fifth straight guide plate 3.3.3 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the first side wall A1 is 6°; the angle of the fifth V-shaped sharp angle structure is 60°, and the length of its two sides is 60 mm;

[0127] The length of the fourth straight guide plate 3.3.2 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200 mm. The angle between it and the fifth straight guide plate 3.3.3 is 152°.

[0128] The length of the third straight deflector 3.3.1 is 0.3 times the width of the return channel A, and its height is the design water depth minus 200mm. The angle between it and the fourth straight deflector 3.3.2 is 151°. The angle of the third V-shaped sharp angle structure is 60°, and the length of both sides is 60mm.

[0129] d1:d2:d3:d4=3:2:1:1;

[0130] The inflow uniformity of the reflux pump is 7.2%.

[0131] From the above simulation results, it can be seen that in this embodiment, based on the data in Table 1, the length range, height range, angle range and ratio of d1:d2:d3:d4 of the multi-channel composite guide component 3 with a reflux pump inlet uniformity of less than 10% are determined by applying the CFD multiphase transient simulation results in the method, thereby obtaining a multi-channel composite guide component 3 with a suitable size structure, ensuring that the mixed liquid flows evenly to each reflux pump suction port, avoiding strong vortex impact on the reflux pump impeller caused by uneven inflow, and preventing damage to the reflux pump.

[0132] Specifically, in this embodiment, the length data, height data, angle data, and the ratio of d1:d2:d3:d4 of the multi-channel composite flow guide component 3 in the simulation result three are selected.

[0133] Comparative Example:

[0134] Different from the embodiment, the degassing and rectifying device described in the embodiment is not installed in the reflux channel A and at the intersection of the reflux channel A and the reflux pump forebay B.

[0135] Water was sampled from the outlet pipes of each reflux pump in the Examples and Comparative Examples to measure gas content and dissolved oxygen. The results are shown in Table 2. Gas content was measured using the dual conductivity probe method, specifically referring to Method B of "Standard Test Method for Electrical Conductivity and Resistivity of Water (ASTM D1125-23)" and calculated using the Maxwell–Garnett equation. Dissolved oxygen was measured using the fluorescence quenching method, specifically referring to Method C of "Standard Test Method for Dissolved Oxygen in Water (ASTM D888-05)."

[0136] Table 2 Measurement results of gas content and dissolved oxygen content

[0137]

[0138] It can be seen from the data in Table 2 that compared with the comparative example, after the degassing rectifier is installed in this embodiment, the gas content and dissolved oxygen content are reduced by 71.13% and 29.41% respectively in terms of degassing, which significantly reduces the gas content and dissolved oxygen content of the reflux mixed liquor, thereby effectively reducing the adverse effects of high gas content and high dissolved oxygen content of the reflux mixed liquor on the denitrification and phosphorus removal of the biochemical pool, and can also prevent cavitation of the reflux pump.

[0139] In addition, compared with the comparative example, after the degassing and rectifying device is installed in this embodiment, the rectification ensures that the mixed liquid flows evenly to the water inlets of each reflux pump, avoiding the strong vortex impacting the reflux pump impeller caused by uneven inflow, and preventing the reflux pump from being damaged.

[0140] contrast Figure 6 and Figure 7 After the degassing and rectifying device is installed in this embodiment, the Figure 6 The jet entrainment at the entrance of the middle reflux pump forebay B and the three-dimensional, large-scale vortex in the reflux pump forebay B guide the effluent from the reflux channel A to flow vertically and evenly to the reflux pump suction port ( Figure 7 ).

[0141] contrast Figure 8 and Figure 9 、 Figure 10 and Figure 11 as well as Figure 12 and Figure 13 After the degassing and rectifying device is installed in this embodiment, the Figure 8 、 Figure 10 and Figure 12 In order to solve the unfavorable flow state where the vertical flow velocity in front of the reflux pump suction port is uneven or even the inflow direction is perpendicular to the reflux pump suction port, the water flow is guided to flow to the reflux pump suction port in a uniform manner in the vertical direction parallel to the reflux pump suction pipe, avoiding the strong vortex impact on the reflux pump impeller caused by the uneven inflow, and preventing the reflux pump from vibrating, inefficient, and even damaging the reflux pump.

[0142] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. Immersed MBR process membrane pool return sludge degassing and rectification device, characterized by: It comprises an air release component (1), a vertical flow guide component (2) and a multi-channel composite flow guide component (3) which are sequentially arranged along the flow direction of the mixed liquid; The number of the air release components (1) is multiple, and they are sequentially arranged in the reflux channel (A) of the MBR membrane pool along the mixed liquid flow direction; a first installation gap is connected or set between each two adjacent groups of the air release components (1); each group of the air release components (1) includes a first frame (1.1) and an air release component (1.2); the number of the air release components (1.2) is multiple, and they are arranged in rows and intervals in the first frame (1.1) along the mixed liquid flow direction; the first frame (1.1) is arranged in the reflux channel (A); a second installation gap is set between each two adjacent rows of the air release components (1.2); the air release components (1.2) in two adjacent rows are staggered; a third installation gap is set between each row of adjacent two air release components (1.2); the air release component (1.2) is an integrally formed V-shaped structure, and its opening direction is the same as the mixed liquid flow direction; The vertical flow guide assembly (2) is vertically arranged at the end of the reflux channel (A), and comprises an upper flow guide channel and a lower flow guide channel which are arranged in parallel and inclined downward, and both are arranged along the flow direction of the mixed liquid; The multi-channel composite flow guide assembly (3) is arranged at the intersection of the reflux channel (A) and the reflux pump forebay (B); the multi-channel composite flow guide assembly (3) comprises a straight section flow guide plate (3.1), a double-fold flow guide plate (3.2) and a triple-fold flow guide plate (3.3) arranged at intervals along the mixed liquid flow section; the straight section flow guide plate (3.1) and the double-fold flow guide plate (3.2) are both connected to the first side wall (A1) of the reflux channel (A); the triple-fold flow guide plate (3.3) is connected to the second side wall (A2) of the reflux channel (A).

2. The submerged MBR process membrane pool return sludge degassing and rectification device according to claim 1, characterized in that: The spacing of the first installation gap is 0.2 to 0.5 times the width of the reflux channel (A).

3. The submerged MBR process membrane pool return sludge degassing and rectification device according to claim 1, characterized in that: The spacing of the second installation gap is 0.01 to 0.3 times the width of the return channel (A); the spacing of the third installation gap is 0.01 to 0.2 times the width of the return channel (A).

4. The submerged MBR process membrane pool return sludge degassing and rectification device according to claim 1, characterized in that: The angle of the V-shaped structure is 30°~75°; The V-shaped structure comprises an integrally formed first connecting plate (1.2.1) and a second connecting plate (1.2.2); the length of the first connecting plate (1.2.1) and the length of the second connecting plate (1.2.2) are both 250-450 mm; the top of the first connecting plate (1.2.1) and the top of the second connecting plate (1.2.2) are both connected to the top of the first frame (1.1), and the bottom of the first connecting plate (1.2.1) and the bottom of the second connecting plate (1.2.2) are both connected to the bottom of the first frame (1.1).

5. The submerged MBR process membrane pool return sludge degassing and rectification device according to claim 1, characterized in that: The first frame (1.1) comprises a first side panel (1.1.1), a second side panel (1.1.2), a first top panel and a first bottom panel; the first side panel (1.1.1) and the second side panel (1.1.2) are arranged opposite to each other and are respectively connected to the first side wall (A1) and the second side wall (A2) on both sides of the reflux channel (A); the first top panel is arranged on the first side panel ( 1.1.1) and the top of the second side plate (1.1.2), and tilted downward; the inclination angle of the first top plate is 3° to 15°; the projected length of the first top plate at the bottom of the reflux channel (A) is 1.0 to 2.5 times the width of the reflux channel (A); the highest point of the first top plate is 0.1m below the design water depth; The first bottom plate is arranged on the first side plate ( 1.1.1) and the bottom end of the second side plate (1.1.2); the length of the first bottom plate is 1.0 to 2.5 times the width of the reflux channel (A); The length of the first side plate (1.1.1) and the length of the second side plate (1.1.2) are both 1.0 to 2.5 times the width of the reflux channel (A).

6. The submerged MBR process membrane pool return sludge degassing and rectification device according to any one of claims 1 to 5, characterized in that: The vertical air guide assembly (2) comprises a second frame and an intermediate plate (2.1); The second frame comprises a third side plate (2.4), a fourth side plate (2.5), a second top plate (2.2) and a second bottom plate (2.3); the third side plate (2.4) and the fourth side plate (2.5) are arranged opposite to each other and are respectively connected to the first side wall (A1) and the second side wall (A2) on both sides of the end of the reflux channel (A); The second top plate (2.2) is arranged on the top ends of the third side plate (2.4) and the fourth side plate (2.5), and is tilted downward; the tilt angle of the second top plate (2.2) is 5° to 25°; the projected length of the second top plate (2.2) at the bottom of the reflux channel (A) is 0.5 to 1.5 times the width of the reflux channel (A); the highest point of the second top plate (2.2) is located 250 to 1000 mm below the design water depth; The second bottom plate (2.3) is horizontally arranged on the bottom ends of the third side plate (2.4) and the fourth side plate (2.5); the length of the second bottom plate (2.3) is 1.0 to 2.5 times the width of the reflux channel (A); The intermediate plate (2.1) is arranged between the second top plate (2.2) and the second bottom plate (2.3), and is arranged parallel to the second top plate (2.2); the two ends of the intermediate plate (2.1) are respectively connected to the third side plate (2.4) and the fourth side plate (2.5); the projected length of the intermediate plate (2.1) at the bottom of the reflux channel (A) is 0.5 to 1.5 times the width of the reflux channel (A); the distance between the intermediate plate (2.1) and the second bottom plate (2.3) is 1 / 3 to 2 / 3 of the height of the vertical flow guide assembly (2); The middle plate (2.1), the second top plate (2.2), the third side plate (2.4) and the fourth side plate (2.5) form the upper flow guide channel; the middle plate (2.1), the second bottom plate (2.3), the third side plate (2.4) and the fourth side plate (2.5) form the lower flow guide channel.

7. The submerged MBR process membrane pool return sludge degassing and rectification device according to claim 6, characterized in that: A first flow channel d1 is formed between the straight section guide plate (3.1) and the adjacent first side wall (A1), a second flow channel d2 is formed between the straight section guide plate (3.1) and the double-fold guide plate (3.2), a third flow channel d3 is formed between the double-fold guide plate (3.2) and the triple-fold guide plate (3.3), and a fourth flow channel d4 is formed between the triple-fold guide plate (3.3) and the adjacent second side wall (A2).

8. The submerged MBR process membrane pool return sludge degassing and rectification device according to claim 7, characterized in that: The included angle between the straight section guide plate (3.1) and the adjacent No. 1 side wall (A1) is 5° to 15°; the length of the straight section guide plate (3.1) is 0.5 to 1.5 times the width of the return channel (A); the height of the straight section guide plate (3.1) is the design water depth minus 200 to 500 mm; both ends of the straight section guide plate (3.1) include a first V-shaped sharp angle structure; the included angle of the first V-shaped sharp angle structure is 30° to 60°; the length of both sides of the first V-shaped sharp angle structure is 50 to 150 mm; The double-fold guide plate (3.2) comprises a first straight guide plate (3.2.1) and a second straight guide plate (3.2.2) connected in one piece; the second straight guide plate (3.2.2) and the first straight guide plate (3.2.1) are arranged in sequence along the flow direction of the mixed liquid; the angle between the first straight guide plate (3.2.1) and the first side wall (A1) is 5° to 35°; the length of the first straight guide plate (3.2.1) is 0.2 to 0.5 times the width of the return channel (A); the height of the first straight guide plate (3.2.1) is the design water depth minus 200 to 500 mm; The included angle between the second straight guide plate (3.2.2) and the first straight guide plate (3.2.1) is 150° to 175°; the length of the second straight guide plate (3.2.2) is 0.2 to 0.6 times the width of the return channel (A); the height of the second straight guide plate (3.2.2) is the designed water depth minus 200 to 500 mm; The end of the first straight guide plate (3.2.1) away from the second straight guide plate (3.2.2) includes a second V-shaped sharp-angle structure; the end of the second straight guide plate (3.2.2) away from the first straight guide plate (3.2.1) includes a third V-shaped sharp-angle structure; the included angles of the second V-shaped sharp-angle structure and the third V-shaped sharp-angle structure are both 30° to 60°; the side lengths of both sides of the second V-shaped sharp-angle structure and the third V-shaped sharp-angle structure are both 50 to 150 mm; The three-fold guide plate (3.3) comprises a third straight guide plate (3.3.1), a fourth straight guide plate (3.3.2) and a fifth straight guide plate (3.3.3) which are integrally connected; the fifth straight guide plate (3.3.3), the fourth straight guide plate (3.3.2) and the third straight guide plate (3.3.1) are arranged in sequence along the flow direction of the mixed liquid; the angle between the fifth straight guide plate (3.3.3) and the first side wall (A1) is 0° to 10°; the angle between the fourth straight guide plate (3.3.2) and the fifth straight guide plate (3.3.3) is 135° to 175°; the angle between the third straight guide plate (3.3.1) and the The included angle of the fourth straight guide plate (3.3.2) is 120°~175°; the length of the fifth straight guide plate (3.3.3) and the length of the third straight guide plate (3.3.1) are both 0.1~0.6 times the width of the return channel (A); the height of the fifth straight guide plate (3.3.3) and the height of the third straight guide plate (3.3.1) are both the design water depth minus 200~500mm; the length of the fourth straight guide plate (3.3.2) is 0.1~1.0 times the width of the return channel (A); the height of the fourth straight guide plate (3.3.2) is both the design water depth minus 200~600mm; The end of the third straight guide plate (3.3.1) away from the fourth straight guide plate (3.3.2) includes a fourth V-shaped sharp-angle structure; the end of the fifth straight guide plate (3.3.3) away from the fourth straight guide plate (3.3.2) includes a fifth V-shaped sharp-angle structure; the included angles of the fourth V-shaped sharp-angle structure and the fifth V-shaped sharp-angle structure are both 30°~60°; the side lengths of both sides of the fourth V-shaped sharp-angle structure and the fifth V-shaped sharp-angle structure are both 50~150mm.

9. The application method of the submerged MBR process membrane pool return sludge degassing and rectification device according to claim 8 is characterized in that: The method comprises using the Navier-Stokes equations and the k-omega SST turbulence model as a control mechanism, using the return pump inlet uniformity as a control parameter, and using CFD multiphase transient simulation results to determine the length range, height range, angle range, and ratio of d1:d2:d3:d4 of the multi-channel composite guide assembly (3) with a return pump inlet uniformity of less than 10% for the return channel (A) and the return pump forebay (B) of MBR membrane tanks of different sizes; Among them, the ratio of d1:d2:d3:d4 is 1~3:1~2:1:

1.

10. The application method of the submerged MBR process membrane pool return sludge degassing and rectification device according to claim 9, characterized in that: The reflux pump inflow uniformity is obtained using the following formula: ； in, Indicates the uniformity of the return pump inflow at a section 0.5m in front of the return pump suction port; It represents the value of the cross-section width along the reflux pump forebay (B) divided into equal sections. The value is twice the number of reflux pumps; The value range is 1 to ; It represents the average flow velocity at the section 0.5 m before the water inlet of the return pump. Its value is obtained by performing surface integration on the velocity values ​​of all calculation nodes on the section obtained from the CFD multiphase transient simulation results. Indicates the The average flow velocity of a subsection located 0.5 m before the water inlet of the return pump is obtained by performing surface integration on the velocity values ​​of all calculation nodes on the subsection obtained from the CFD multiphase transient simulation results.

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