A wastewater advanced treatment and energy recovery system

Abstract

The present application relates to a kind of wastewater advanced treatment and energy recovery system, including sequentially connected membrane filtration device, activated carbon filter device, ion exchange membrane device and reverse osmosis device, several layers of membrane filtration components are evenly arranged in membrane filtration device, and membrane filtration component is perpendicular to the water flow direction in membrane filtration device;Activated carbon filter device is equipped with activated carbon filter bed and several first energy recovery bins;The surface of first energy recovery bin is evenly densely covered with through hole, and two ends are connected with booster pump inlet and energy recovery branch pipe respectively, and the energy of water body is recovered by booster pump and energy recovery branch pipe;The system further includes second energy recovery bin, and second energy recovery bin is equipped with water distribution main pipe and several water distribution pipes connected with each other, and energy recovery main pipe and water production pipe of reverse osmosis device are connected with water distribution main pipe, and energy concentrating device is provided on water distribution pipe, and water with energy is used to configure cleaning water in second energy recovery bin after energy is improved by energy concentrating device, and is used to clean the membrane material of the system.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, specifically relating to a wastewater deep treatment and energy recovery system. Background Technology

[0002] Advanced wastewater treatment typically refers to the deep purification of wastewater after pretreatment and biochemical treatment, in order to remove residual suspended solids, COD, color, ions and other pollutants from the wastewater, so that it can meet higher water quality standards such as reused reclaimed water or even pure water.

[0003] Currently, advanced wastewater treatment mainly employs multi-media filtration combined with membrane treatment, such as ultrafiltration, nanofiltration, RO reverse osmosis, EDI electro-driven membranes, and ion exchange membranes, as well as combinations thereof. However, these membrane treatment processes often suffer from low treatment efficiency and require high pressure and high flow rates, resulting in high energy consumption. Consequently, the treated wastewater still contains a significant amount of residual energy, which is often not recovered or utilized and is instead wasted, leading to a waste of energy resources. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a wastewater deep treatment and energy recovery system, comprising a membrane filtration device, an activated carbon filtration device, an ion exchange membrane device, and a reverse osmosis device connected in sequence. Several layers of membrane filtration components are uniformly arranged inside the membrane filtration device, and the membrane filtration components are perpendicular to the water flow direction inside the membrane filtration device.

[0005] The activated carbon filtration device is equipped with an activated carbon filter bed and several first energy recovery chambers. The surface of the first energy recovery chambers is evenly covered with through holes. The two ends of the first energy recovery chambers are connected to the inlet of the booster pump and the energy recovery branch pipe, respectively. The water entering the activated carbon filtration device has energy. After passing through the activated carbon filter bed, the water can enter the first energy recovery chamber and be recovered by the booster pump and the energy recovery branch pipe.

[0006] The system also includes a second energy recovery chamber, which is equipped with a main water distribution pipe and several water distribution pipes connected to each other. The main water distribution pipe and the product water pipe of the reverse osmosis unit are connected to the main water distribution pipe. The water distribution pipes are equipped with energy-concentrating devices. After the energy-carrying water passes through the energy-concentrating devices to increase its energy, it is used in the second energy recovery chamber to prepare cleaning water for cleaning the membrane materials of the membrane filtration device, ion exchange membrane device and reverse osmosis unit.

[0007] Optionally, the membrane filtration device is a closed chamber, preferably square; an inlet pipe and an outlet pipe are respectively provided on the front and rear sides of the membrane filtration device for inputting wastewater and outputting filtered water; the inlet pipe is connected to a pressurizing device to pressurize the inlet water so that the wastewater can pass through each layer of membrane filtration components.

[0008] Fixing devices are provided on the left and right sides of the membrane filtration device. There is a pair of fixing devices, which are respectively located at corresponding positions on the left and right sides to support the two ends of the membrane filtration assembly, so that the membrane filtration assembly is parallel to the front side of the membrane filtration device.

[0009] Optionally, the membrane filtration assembly includes a membrane material and a support plate that are parallel to each other. One side of the membrane material faces the front side of the membrane filtration device, the other side of the membrane material contacts one side of the support plate, and the other side of the support plate faces the rear side of the membrane filtration device. The support plate is evenly and densely covered with through holes, so that the wastewater is filtered twice by the membrane material and the support plate when it passes through each membrane filtration assembly.

[0010] Optionally, the activated carbon filtration device is uniformly filled with activated carbon to form an activated carbon filter bed, and several first energy recovery chambers are uniformly embedded in the activated carbon filter bed; the interior of the first energy recovery chamber is hollow, and the sides are uniformly and densely covered with through holes, so that the water passing through the activated carbon filter bed can enter and exit the first energy recovery chamber; the first energy recovery chamber is cylindrical, and its central axis is horizontal.

[0011] Optionally, the first energy recovery chamber includes a left compartment and a right compartment, both of which are cylindrical and have horizontal central axes. The connection point between the left and right compartments is the apex of the first energy recovery chamber. The left and right compartments have an angle of 90-180°, and the apex points to the upstream side of the activated carbon filter. The internal spaces of the left and right compartments are connected.

[0012] Optionally, the end of the left compartment opposite to the vertex is the left connecting end, and the end of the right compartment opposite to the vertex is the right connecting end. The right connecting end is connected to the energy recovery branch pipe, which is parallel to the right compartment. The energy recovery branch pipes of each first energy recovery compartment are connected in parallel and then connected to the energy recovery main pipe. The outlet of the energy recovery main pipe is connected to the inlet pipe of the membrane filter and the main water distribution pipe. The left connecting end of each first energy recovery compartment is connected in parallel to the inlet of the booster pump.

[0013] The inner diameter of the left connecting end gradually decreases along the direction pointing to the booster pump; the inner diameter of the right connecting end gradually decreases along the direction pointing to the energy recovery main pipe, which is conducive to further increasing the flow rate of water discharged from both ends of the first energy recovery chamber.

[0014] Optionally, the left compartment is fitted with two first support rings, which are respectively positioned near the two ends of the left compartment and do not contact the outer surface of the left compartment; a plurality of first stirring elements are evenly arranged along the circumference of the left compartment. The first stirring elements are rectangular, with one long side fixed to the two first support rings at both ends, and the other long side pointing towards the inside of the activated carbon filter bed; the first stirring elements are made of steel wires woven into a mesh with cross-shaped steel wires, and the mesh aperture is larger than the activated carbon particle size.

[0015] A drive motor is connected to the first support ring near the left connection end to drive the first stirring component to rotate.

[0016] Optionally, the right compartment is fitted with two second support rings, which are respectively positioned near the two ends of the right compartment and do not contact the outer surface of the right compartment; a plurality of second stirring elements are evenly arranged along the circumference of the right compartment. The second stirring elements are rectangular, with one long side fixed to the two second support rings at both ends, and the other long side pointing towards the inside of the activated carbon filter bed; on the outer surface of the right compartment, the second stirring elements are made of steel wires woven into a mesh with cross-shaped steel wires, and the mesh aperture is larger than the activated carbon particle size;

[0017] A second support ring near the right connection end is connected to a drive motor, which is used to drive the second stirring component to rotate.

[0018] Optionally, the top of the second energy recovery chamber is provided with a water distribution main pipe and a chemical inlet, and the bottom is provided with a cleaning water outlet. The top ends of several water distribution pipes are evenly connected to both sides of the water distribution main pipe along the length of the water distribution main pipe, and the bottom ends of the water distribution pipes extend into the lower part of the second energy recovery chamber. The energy-concentrating device is located above the liquid surface of the second energy recovery chamber, and the chemical inlet is connected to an external chemical tank.

[0019] The cleaning water outlet is connected to the inlet of the cleaning water pump of the membrane filtration device, ion exchange membrane device, and reverse osmosis device.

[0020] Further optionally, the energy-concentrating device includes an energy-concentrating chamber and several drainage pipes, with a water distribution pipe passing through the energy-concentrating chamber and the internal space of the energy-concentrating chamber communicating with the internal space of the water distribution pipe. The energy-concentrating chamber is a frustum-shaped structure with a larger top and a smaller bottom, and several drainage pipes are evenly arranged along the circumference of the energy-concentrating chamber.

[0021] One end of the drainage tube is connected to the energy-concentrating chamber, and the other end has an opening facing downwards, introducing outside air into the energy-concentrating chamber. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the wastewater deep treatment and energy recovery system in Example 1;

[0023] Figure 2 This is a schematic diagram of a membrane filtration assembly;

[0024] Figure 3 This is a schematic diagram of the second energy recovery chamber;

[0025] Figure 4 This is a schematic diagram of a focusing device;

[0026] Figure 5 This is a schematic diagram of the first energy recovery chamber in Example 2;

[0027] Figure 6 This is a schematic diagram showing the positional relationship between the center axes of the left and right sub-compartments in Example 4.

[0028] In the attached diagram, 1-membrane filtration device, 2-activated carbon filtration device, 3-ion exchange membrane device, 4-reverse osmosis device, 5-membrane filtration assembly, 6-activated carbon filter bed, 7-first energy recovery chamber, 8-second energy recovery chamber, 9-booster pump, 10-energy recovery branch pipe, 11-energy recovery main pipe, 12-water distribution main pipe, 13-water distribution pipe, 14-fixed device, 15-membrane material, 16-support plate, 17-cleaning water outlet, 18-energy concentration chamber, 19-drainage pipe, 20-left compartment, 21-right compartment, 22-left connection end, 23-right connection end, 24-first support ring, 25-second support ring, 26-first agitator, 27-second agitator. Detailed Implementation

[0029] Example 1

[0030] This embodiment provides a wastewater deep treatment and energy recovery system, such as Figures 1-4 As shown, it includes a membrane filtration device 1, an activated carbon filtration device 2, an ion exchange membrane device 3, and a reverse osmosis device 4 connected in sequence. Three layers of membrane filtration components 5 are uniformly arranged inside the membrane filtration device 1, and the membrane filtration components 5 are perpendicular to the water flow direction inside the membrane filtration device 1.

[0031] The activated carbon filter device 2 is equipped with an activated carbon filter bed 6 and several first energy recovery chambers 7. The surface of the first energy recovery chamber 7 is evenly covered with through holes. The two ends of the first energy recovery chamber 7 are respectively connected to the inlet of the booster pump 9 and the energy recovery branch pipe 10. The water entering the activated carbon filter device 2 of the membrane filter device 1 has energy. After passing through the activated carbon filter bed 6, the water can enter the first energy recovery chamber 7 and be recovered by the booster pump 9 and the energy recovery branch pipe 10.

[0032] The system also includes a second energy recovery chamber 8, which is equipped with a main water distribution pipe 12 and several water distribution pipes 13 connected to each other. The main energy recovery pipe 11 and the product water pipe of the reverse osmosis device 4 are connected to the main water distribution pipe 12. The water distribution pipes 13 are equipped with energy-concentrating devices. After the energy-carrying water passes through the energy-concentrating devices to increase its energy, it is used in the second energy recovery chamber 8 to prepare cleaning water for cleaning the membrane materials of the membrane filtration device 1, the ion exchange membrane device 3 and the reverse osmosis device 4.

[0033] The membrane filtration device 1 is a closed chamber and is square; an inlet pipe and an outlet pipe are respectively provided on the front and rear sides of the membrane filtration device 1, which are used to input wastewater and output filtered water respectively; the inlet pipe is connected to a pressurizing device to pressurize the inlet water so that the wastewater can pass through each layer of membrane filtration components 5.

[0034] Fixing devices 14 are provided on the left and right sides of the membrane filtration device 1, respectively. The fixing devices 14 are a pair, respectively located at corresponding positions on the left and right sides, and are used to support the two ends of the membrane filtration assembly 5, so that the membrane filtration assembly 5 is parallel to the front side of the membrane filtration device 1. The outlet pipe is connected to the activated carbon filtration device 2.

[0035] The fixing device 14 is a U-shaped, slender slot, and is vertically arranged to facilitate the insertion or removal of the membrane filter assembly 5 from the fixing device 14.

[0036] The membrane filtration assembly 5 includes parallel membrane materials 15 and a support plate 16. One side of the membrane material 15 faces the front side of the membrane filtration device 1, and the other side of the membrane material 15 contacts one side of the support plate 16. The other side of the support plate 16 faces the rear side of the membrane filtration device 1. The support plate 16 has uniformly distributed through holes, so that wastewater is filtered twice by the membrane material 15 and the support plate 16 when passing through each membrane filtration assembly 5. The membrane material 15 can be a fluorocarbon fiber membrane with a pore size of 0.1-1 mm, and the support plate 16 has a pore size of 10-20 mm.

[0037] After being pressurized, the wastewater can pass through the multi-layer membrane filter assembly 5 of the membrane filtration device 1. Suspended particles in the wastewater form a lava membrane thin layer and a filter media layer on the membrane surface, improving the filtration effect and fine particle filtration efficiency of the membrane filter assembly 5. The support plate 16 supports the membrane material on the downstream side, increasing the membrane layer strength and facilitating the formation of a dense media layer. This reduces contamination and clogging of the membrane material itself during filtration, thereby improving the pollutant filtration and purification effect of the membrane filtration device 1.

[0038] The activated carbon filter device 2 is uniformly filled with activated carbon to form an activated carbon filter bed 6. Several first energy recovery chambers 7 are uniformly buried in the activated carbon filter bed 6. The interior of the first energy recovery chamber 7 is hollow, and the sides are uniformly covered with through holes, so that the water that has passed through the activated carbon filter bed 6 can enter and exit the first energy recovery chamber 7.

[0039] The first energy recovery chamber 7 is a flat cylinder with a horizontal central axis. Both ends of the first energy recovery chamber 7 contact the two opposite sidewalls of the activated carbon filter device 2. The pore size of the first energy recovery chamber is smaller than the particle size of the granular activated carbon to prevent activated carbon from entering the first energy recovery chamber and being lost.

[0040] The energy recovery branch pipe 10 is set horizontally, and the inlet points to the upstream side of the activated carbon filter device 2, so as to facilitate the flow of water into the energy recovery branch pipe 10; the energy recovery branch pipes 10 of each first energy recovery chamber are connected in parallel and then connected to the energy recovery main pipe 11. The outlet of the energy recovery main pipe 11 is connected to the inlet pipe of the membrane filter device 1 and the water distribution main pipe 12, so that the water with kinetic energy recovered by the first energy recovery chamber is returned to the membrane filter device 1 and the second energy recovery chamber 8, utilizing the kinetic energy in the water;

[0041] Each first energy recovery chamber is connected in parallel to the inlet of the booster pump 9 at one end near the booster pump 9, providing the booster pump 9 with kinetic water. The inlet of the booster pump 9 is also horizontal and perpendicular to the energy recovery branch pipe 10.

[0042] The membrane filtration device 1 has a certain internal pressure, and its effluent also has pressure and energy. This energy-carrying water enters the activated carbon filter bed 6, where it comes into contact with and mixes with the granular activated carbon layer. The activated carbon adsorbs and purifies pollutants such as microparticles, ions, and particles in the water, achieving both energy recovery and effective water purification. The water in the activated carbon filtration device 2 can enter and exit the first energy recovery chamber. When the water flows out evenly from the through-holes of the first energy recovery chamber, it comes into contact with and fluidizes the activated carbon, activating the microbubbles in the pores of the granular activated carbon. This creates a deep treatment effect similar to air flotation separation, effectively removing colloids, particles, and other pollutants from the water. This tiered treatment further improves the deep purification effect of water pollutants, while simultaneously achieving the full recovery and utilization of residual kinetic energy through tiered gradation.

[0043] At the same time, water containing pressure and kinetic energy enters the first energy recovery chamber. On the one hand, the water enters the inlet of the booster pump 9 and is used as the feed water for the booster pump 9 to improve the kinetic energy of the feed water, achieve energy saving, and reduce the energy consumption of the booster pump 9. On the other hand, the water is recycled to the membrane filter device 1 and the second energy recovery chamber 8 through the energy recovery branch pipe 10 and the energy recovery main pipe 11.

[0044] In this embodiment, the ion exchange membrane device 3 and the reverse osmosis device 4 adopt conventional structures and settings in the art. The product water pipe of the reverse osmosis device 4 is connected to the main water distribution pipe 12 and the inlet water pipe of the membrane filter device 1. It can also be connected to the inlet of the cleaning water pump of the ion exchange membrane device 3 and the reverse osmosis device 4 for better cleaning of the ion exchange membrane device 3 and the reverse osmosis device 4.

[0045] The second energy recovery chamber 8 has a water distribution main pipe 12 and a chemical inlet at the top, and a cleaning water outlet 17 at the bottom. The top ends of four water distribution pipes 13 are evenly connected to both sides of the water distribution main pipe 12 along its length. The bottom ends of the water distribution pipes 13 extend into the lower part of the second energy recovery chamber 8. The energy-concentrating device is located above the liquid surface in the second energy recovery chamber 8. The chemical inlet is connected to an external chemical tank. The bottom of the second energy recovery chamber 8 is conical to facilitate the collection of solid impurities contained in the water supplied by the water distribution pipe 13.

[0046] The inlet of the cleaning water pump of the cleaning water outlet 17 is connected to the membrane filter device 1, the ion exchange membrane device 3 and the reverse osmosis device 4.

[0047] The energy-concentrating device includes an energy-concentrating chamber 18 and two drainage pipes 19. A water distribution pipe 13 passes through the energy-concentrating chamber 18, and the internal space of the energy-concentrating chamber 18 is connected to the internal space of the water distribution pipe 13. The energy-concentrating chamber 18 is a frustum-shaped structure with a larger top and a smaller bottom. Several drainage pipes 19 are evenly arranged along the circumference of the energy-concentrating chamber 18.

[0048] One end of the drainage tube 19 is connected to the energy-concentrating chamber 18, and the opening at the other end faces downwards, introducing outside air into the energy-concentrating chamber 18.

[0049] The second energy recovery chamber 8 is used to prepare the cleaning water for the membrane cleaning material. The product water from the reverse osmosis unit 4 and the water input from the energy recovery main pipe 11 contain energy. After this water and the reagents enter the second energy recovery chamber 8, the reagents can be mixed more quickly and efficiently under the action of the kinetic energy in the water, realizing energy recovery. After the water is evenly distributed through the water distribution main pipe 12, it enters each water distribution pipe 13. When the water flows through the energy-concentrating chamber 18, the flow velocity is relatively fast, which also drives the surrounding air flow, thereby reducing the pressure in the vicinity and creating a suction force on the outside air in the energy-concentrating chamber 18. The outside air enters the energy-concentrating chamber 18 through the guide pipe 19, and the direction of air entry is tangential. While the air mixes quickly with the water in the energy-concentrating chamber 18, it also helps to form a rotating water flow, further increasing the kinetic energy of the water. At the same time, the shape of the energy-concentrating chamber 18, which is larger at the top and smaller at the bottom, can further increase the flow velocity of the water-gas mixture. After this mixture enters the second energy recovery chamber 8, it forms a forced turbulent mixing with the reagents, improving the mixing efficiency and saving energy. The water entering the energy recovery main 11 contains broken activated carbon residue, which can accumulate and deposit at the conical bottom of the second energy recovery chamber 8.

[0050] The drainage tube 19 can be inverted "V" shaped or horizontal. The opening of the drainage tube 19 faces downward to prevent large solids or liquids (such as rainwater) falling from the air from entering the drainage tube 19.

[0051] Example 2

[0052] This embodiment provides a wastewater deep treatment and energy recovery system, which is the same as that in Embodiment 1, except that, as Figure 5 As shown, the first energy recovery chamber includes a left compartment 20 and a right compartment 21. Both the left compartment 20 and the right compartment 21 are cylindrical, and their central axes are horizontal. The connection point between the left compartment 20 and the right compartment 21 is the apex of the first energy recovery chamber. The left compartment 20 and the right compartment 21 have an angle of 90-180°, and this apex points to the upstream side of the activated carbon filter device 2. The internal spaces of the left compartment 20 and the right compartment 21 are connected.

[0053] The end of the left compartment 20 opposite to the vertex is the left connecting end 22, and the end of the right compartment 21 opposite to the vertex is the right connecting end 23. The right connecting end 23 is connected to the energy recovery branch pipe 10, which is parallel to the right compartment 21. The energy recovery branch pipes 10 of each first energy recovery compartment are connected in parallel and then connected to the energy recovery main pipe 11. The outlet of the energy recovery main pipe 11 is connected to the inlet pipe of the membrane filter device 1 and the water distribution main pipe 12. The left connecting end 22 of each first energy recovery compartment is connected in parallel to the inlet of the booster pump 9.

[0054] The inner diameter of the left connecting end 22 gradually decreases along the direction pointing towards the booster pump 9; the inner diameter of the right connecting end 23 gradually decreases along the direction pointing towards the energy recovery main pipe 11, which is beneficial to further increase the flow rate of water discharged from both ends of the first energy recovery chamber. The side walls of the left connecting end 22 and the right connecting end 23 are not provided with through holes and are solid plates.

[0055] Two first support rings 24 are fitted around the outer side of the left compartment 20. The two first support rings 24 are respectively positioned close to both ends of the left compartment 20 and do not contact the outer surface of the left compartment 20. Several first stirring elements 26 are evenly arranged along the circumference of the left compartment 20. The first stirring elements 26 are rectangular, with one long side fixed to the two first support rings 24 at both ends, and the other long side pointing towards the inside of the activated carbon filter bed 6. The first stirring elements 26 are made of steel wires woven into a mesh with cross-shaped steel wires, and the mesh size is larger than the activated carbon particle size.

[0056] A drive motor is connected to the first support ring 24 near the left connecting end 22 to drive the first stirring component 26 to rotate. The first support ring 24 is concentrically arranged with the left compartment 20.

[0057] Two second support rings 25 are fitted around the outer side of the right compartment 21. The two second support rings 25 are respectively located near the two ends of the right compartment 21 and do not contact the outer surface of the right compartment 21. Several second stirring elements 27 are evenly arranged along the circumference of the right compartment 21. The second stirring elements 27 are rectangular, with one long side fixed at both ends to the two second support rings 25, and the other long side pointing towards the inside of the activated carbon filter bed 6. The second stirring elements 27 are made of steel wires woven into a mesh with cross-shaped steel wires, and the mesh size is larger than the activated carbon particle size.

[0058] A drive motor is connected to the second support ring 25 near the right connecting end 23 to drive the second stirring element 27 to rotate. The second support ring 25 is concentrically arranged with the right compartment 21. The two drive motors corresponding to the first support ring 24 and the second support ring 25 can be located inside or outside the activated carbon filter device 2.

[0059] The mixing components in adjacent compartments do not come into contact with each other to avoid collisions.

[0060] The water flow direction in the activated carbon filter device 2 is from the upstream side to the downstream side. The first energy recovery chamber, which is parallel to the upstream side and is straight, obstructs the water flow to a certain extent. After the water enters the first energy recovery chamber, most of it flows out of the first energy recovery chamber from the opposite side. Only a small part is utilized by the booster pump 9 and flows into the energy recovery branch pipe 10. To address these issues, this embodiment provides a bent first energy recovery chamber. The left compartment 20 and the right compartment 21 form an angle, creating an arrow shape with the apex pointing towards the upstream side of the activated carbon filter 2. After water enters the left compartment 20 and the right compartment 21, it can flow along the left compartment 20 or the right compartment 21 to a certain extent, reducing the loss of water dynamics and conforming to the water flow. This allows more water to flow to the booster pump 9 and the energy recovery pipe 10. The amount of water supplied to the booster pump 9 and the energy recovery pipe 10 can be adjusted according to the required water flow. For example, flow valves can be installed at the inlet of the booster pump 9 and the inlet of the energy recovery pipe 10, so that the water not needed by the booster pump 9 and the energy recovery pipe 10 can still be discharged into the activated carbon filter bed 6.

[0061] The activated carbon filter bed 6 is filled with granular activated carbon. After a period of use, channeling and dead zones may appear in the bed, causing uneven flow of wastewater and consuming the kinetic energy of the water. This invention provides several first agitators 26 and second agitators 27 outside the left compartment 20 and right compartment 21. When the agitators rotate, they agitate the surrounding granular activated carbon, achieving a loosening effect, which helps improve the bed's packing and increases filtration efficiency. The agitators are mesh-like, which loosens the activated carbon while reducing rotational resistance, minimizing the energy consumption of the drive motor, and preventing excessive agitation of the bed, which could lead to uneven packing.

[0062] Example 3

[0063] This embodiment provides a wastewater deep treatment and energy recovery system, which is the same as that in embodiment 2, except that the left compartment 20 is provided with a number of first accelerators. The first accelerators are evenly arranged in several layers along the central axis of the left compartment 20, and each layer is parallel to the circular cross section of the left compartment 20. Each layer is evenly arranged with a number of first accelerators.

[0064] The first accelerator is a cylindrical shape with one end larger than the other. The smaller end of the first accelerator points to the left connecting end 22, and the larger end points to the vertex.

[0065] The right compartment 21 is equipped with several second accelerators. The second accelerators are evenly arranged in several layers along the central axis of the right compartment 21. Each layer is parallel to the circular cross-section of the right compartment 21, and each layer is evenly arranged with several second accelerators.

[0066] The second accelerator is a cylindrical shape with one end larger than the other. The smaller end of the second accelerator points to the right connection end 23, and the larger end points to the vertex.

[0067] The water entering the left compartment 20 flows partially along its length, passing through various first accelerators to increase its velocity and compensate for the kinetic energy lost due to the change in flow direction. This also increases the water's kinetic energy. After a final acceleration at the left connecting end 22, it enters the booster pump 9. The acceleration principle in the right compartment 21 is the same as that in the left compartment 20. The design of the accelerators and connecting ends increases the water velocity without increasing energy consumption. The number of accelerators and the size of the connecting ends are determined based on the actual wastewater treatment requirements.

[0068] The activated carbon filter bed 6 is equipped with two types of first energy recovery chambers, including a left compartment 20 and a right compartment 21. One type is a first energy recovery chamber equipped with an accelerator, called the accelerated recovery chamber; the other type is a first energy recovery chamber without an accelerator, called the empty recovery chamber.

[0069] Several layers of recovery chambers are evenly arranged from the upstream side to the downstream side of the activated carbon filter device 2. Each layer has several accelerated recovery chambers and empty recovery chambers arranged alternately from top to bottom. The recovery chambers of adjacent layers are staggered vertically. For example, the height of an accelerated recovery chamber corresponds to the height between the adjacent accelerated recovery chambers and empty recovery chambers in the adjacent layers.

[0070] In one specific implementation, three layers of recovery chambers are evenly arranged from the upstream side to the downstream side of the activated carbon filter device 2. The layer closest to the upstream side is the first layer, the layer closest to the downstream side is the third layer, and the middle layer is the third layer. The first layer consists of an accelerated recovery chamber, an empty recovery chamber, an accelerated recovery chamber, and an empty recovery chamber, arranged from top to bottom, with a vertical spacing of 2h between adjacent recovery chambers. The second layer consists of an accelerated recovery chamber, an empty recovery chamber, an accelerated recovery chamber, and an empty recovery chamber, arranged from top to bottom, with a vertical spacing of 2h between adjacent recovery chambers. The height of the first accelerated recovery chamber in the second layer corresponds to the height between the two upper accelerated recovery chambers and the empty recovery chamber in the first layer. The third layer consists of an empty recovery chamber, an accelerated recovery chamber, an empty recovery chamber, and an accelerated recovery chamber, arranged from top to bottom, with a vertical spacing of 2h between adjacent recovery chambers. The height of each recovery chamber in the third layer corresponds one-to-one with the height of each recovery chamber in the first layer.

[0071] Because the first energy recovery chamber is positioned horizontally within the activated carbon bed, and the accelerator within the accelerated recovery chamber also provides some obstruction to the water, the obstruction effect of the empty recovery chamber is negligible. The rotating agitator can accelerate the water to some extent, supplementing its kinetic energy. This invention, by arranging the accelerated recovery chamber and the empty recovery chamber separately and alternately as described above, achieves a more balanced distribution of kinetic energy in the water within the activated carbon bed, minimizing energy loss and maximizing the utilization of water energy, while simultaneously improving the activated carbon filtration effect.

[0072] Example 4

[0073] This embodiment provides a wastewater deep treatment and energy recovery system, which is the same as that in Embodiment 2, except that, as Figure 6 As shown, the intersection of the center axes of the left and right compartments is the center point. The straight line parallel to the upstream side of the activated carbon filter, where the center point is located, is the standard line. The angle between the center axis of the left compartment and the standard line is equal to the angle between the center axis of the right compartment and the standard line.

[0074] The ratio of the number of membrane filter layers in the membrane filtration device to the angle between the center axis of the left compartment and the standard line is 1:5. That is, the membrane filter layer has 5 layers, the angle between the center axis of the left compartment and the standard line is 25°, and the angle between the center axis of the left compartment and the center axis of the right compartment is 130°.

[0075] The inventors have discovered that the more layers of membrane filtration components in a membrane filtration device, the greater the obstruction effect on wastewater. A smaller angle between the central axes of the left and right compartments is more in line with the flow direction of the water in the activated carbon bed, which can minimize the loss of water kinetic energy.

[0076] Example 5

[0077] This embodiment provides a wastewater deep treatment and energy recovery system, which is the same as that in embodiment 2. The difference is that the ratio of the number of membrane filter components in the membrane filter device to the angle between the center axis of the left compartment and the standard line is 1:7, that is, the number of membrane filter components is 5, the angle between the center axis of the left compartment and the standard line is 35°, and the angle between the center axis of the left compartment and the center axis of the right compartment is 110°.

[0078] Example 6

[0079] This embodiment provides a wastewater deep treatment and energy recovery system, which is the same as that in embodiment 2. The difference is that the ratio of the number of membrane filter components in the membrane filter device to the angle between the center axis of the left compartment and the standard line is 1:4, that is, the number of membrane filter components is 5, the angle between the center axis of the left compartment and the standard line is 20°, and the angle between the center axis of the left compartment and the center axis of the right compartment is 140°.

[0080] Example 7

[0081] This embodiment provides a wastewater deep treatment and energy recovery system, which is the same as that in embodiment 2. The difference is that the ratio of the number of membrane filter components in the membrane filter device to the angle between the center axis of the left compartment and the standard line is 1:8, that is, the number of membrane filter components is 5, the angle between the center axis of the left compartment and the standard line is 40°, and the angle between the center axis of the left compartment and the center axis of the right compartment is 100°.

[0082] Table 1 Comparison of water kinetic energy within the energy recovery pipes of the first energy recovery chamber in Examples 4-7 Table 1 Comparison of water kinetic energy in the first energy recovery chamber Example 4-7

[0083] project Water flow velocity (cm / min) Example 4 80 Example 5 87 Example 6 70 Example 7 72

[0084] The ratio of the number of membrane filter layers in the membrane filtration device to the angle between the central axis of the left compartment and the standard line determines the ratio of the number of membrane filter layers to the angle between the central axes of the left and right compartments. As shown in the table above, the smaller the angle between the central axes of the left and right compartments, the greater the water flow velocity in the energy recovery pipe, and the more kinetic energy the water contains. However, if the angle between the central axes of the left and right compartments is too small, and the left and right compartments are too close, a significant amount of water from the activated carbon filter bed will not enter the first energy recovery compartment, similarly reducing the water flow velocity in the energy recovery pipe.

Claims

1. A wastewater deep treatment and energy recovery system, characterized in that, It includes a membrane filtration device, an activated carbon filtration device, an ion exchange membrane device and a reverse osmosis device connected in sequence. Several layers of membrane filtration components are evenly arranged inside the membrane filtration device, and the membrane filtration components are perpendicular to the water flow direction inside the membrane filtration device. The activated carbon filtration device is equipped with an activated carbon filter bed and several first energy recovery chambers. The surface of the first energy recovery chambers is evenly covered with through holes, and the two ends of the first energy recovery chambers are respectively connected to the inlet of the booster pump and the energy recovery branch pipe. The system also includes a second energy recovery chamber, which is equipped with a main water distribution pipe and several water distribution pipes connected to each other. The main water distribution pipe and the product water pipe of the reverse osmosis unit are connected to the main water distribution pipe. The water distribution pipe is equipped with an energy-concentrating device. After the energy-carrying water passes through the energy-concentrating device to increase its energy, it is used in the second energy recovery chamber to prepare cleaning water for cleaning the membrane materials of the membrane filtration device, ion exchange membrane device and reverse osmosis unit. The activated carbon filtration device is uniformly filled with activated carbon to form an activated carbon filter bed. Several first energy recovery chambers are uniformly buried in the activated carbon filter bed. The interior of the first energy recovery chamber is hollow, and the sides are uniformly covered with through holes, so that the water that has passed through the activated carbon filter bed can enter and exit the first energy recovery chamber. The first energy recovery chamber includes a left compartment and a right compartment. Both the left and right compartments are cylindrical and their central axes are horizontal. The connection point between the left and right compartments is the apex of the first energy recovery chamber. The left and right compartments have an angle of 90-180°, and the apex points to the upstream side of the activated carbon filter device. The internal spaces of the left and right compartments are connected. The end of the left compartment opposite to the vertex is the left connecting end, and the end of the right compartment opposite to the vertex is the right connecting end. The right connecting end is connected to the energy recovery branch pipe, which is parallel to the right compartment. The energy recovery branch pipes of each first energy recovery compartment are connected in parallel and then connected to the main energy recovery pipe. The outlet of the main energy recovery pipe is connected to the inlet pipe of the membrane filter and the main water distribution pipe. The left connecting end of each first energy recovery compartment is connected in parallel to the inlet of the booster pump. The inner diameter of the left connecting end gradually decreases along the direction pointing to the booster pump; the inner diameter of the right connecting end gradually decreases along the direction pointing to the energy recovery main pipe, which is conducive to further increasing the flow rate of water discharged from both ends of the first energy recovery chamber.

2. The wastewater deep treatment and energy recovery system according to claim 1, characterized in that, The membrane filtration device is a closed chamber and is square in shape. Inlet pipe and outlet pipe are respectively provided on the front and rear sides of the membrane filtration device for inputting wastewater and outputting filtered water, respectively. The inlet pipe is connected to a pressurizing device to pressurize the inlet water so that the wastewater can pass through each layer of membrane filtration components. Fixing devices are provided on the left and right sides of the membrane filtration device. There is a pair of fixing devices, which are respectively located at corresponding positions on the left and right sides to support the two ends of the membrane filtration assembly, so that the membrane filtration assembly is parallel to the front side of the membrane filtration device.

3. The wastewater deep treatment and energy recovery system according to claim 2, characterized in that, The membrane filtration assembly includes a membrane material and a support plate that are parallel to each other. One side of the membrane material faces the front side of the membrane filtration device, and the other side of the membrane material contacts one side of the support plate. The other side of the support plate faces the rear side of the membrane filtration device. The support plate is evenly and densely covered with through holes, so that the wastewater is filtered twice by the membrane material and the support plate when it passes through each membrane filtration assembly.

4. The wastewater deep treatment and energy recovery system according to claim 1, characterized in that, The left compartment is fitted with two first support rings, which are respectively positioned near the two ends of the left compartment and do not contact the outer surface of the left compartment. Several first stirring elements are evenly arranged along the circumference of the left compartment. Each first stirring element is rectangular, with one long side fixed to the two first support rings at both ends, and the other long side pointing towards the inside of the activated carbon filter bed. The first stirring element is a mesh woven from intersecting steel wires, with the mesh pore size larger than the activated carbon particle size. A drive motor is connected to the first support ring near the left connection end to drive the first stirring component to rotate.

5. The wastewater deep treatment and energy recovery system according to claim 1, characterized in that, The right compartment is fitted with two second support rings, which are respectively located near the two ends of the right compartment and do not contact the outer surface of the right compartment. Several second stirring elements are evenly arranged along the circumference of the right compartment. The second stirring elements are rectangular, with one long side fixed to the two second support rings at both ends, and the other long side pointing towards the inside of the activated carbon filter bed. The second stirring elements are made of steel wires woven into a mesh with cross-shaped steel wires, and the mesh size is larger than the activated carbon particle size. A second support ring near the right connection end is connected to a drive motor, which is used to drive the second stirring component to rotate.

6. The wastewater deep treatment and energy recovery system according to claim 1, characterized in that, The top of the second energy recovery chamber is equipped with a water distribution main pipe and a chemical inlet, and the bottom is equipped with a cleaning water outlet. The top ends of several water distribution pipes are evenly connected to both sides of the water distribution main pipe along its length. The bottom ends of the water distribution pipes extend into the lower part of the second energy recovery chamber. The energy-concentrating device is located above the liquid surface of the second energy recovery chamber. The chemical inlet is connected to an external chemical tank. The cleaning water outlet is connected to the inlet of the cleaning water pump of the membrane filtration device, ion exchange membrane device, and reverse osmosis device.

7. The wastewater deep treatment and energy recovery system according to claim 6, characterized in that, The energy-concentrating device includes an energy-concentrating chamber and several drainage pipes. A water distribution pipe passes through the energy-concentrating chamber, and the internal space of the energy-concentrating chamber is connected to the internal space of the water distribution pipe. The energy-concentrating chamber is a frustum-shaped structure that is larger at the top and smaller at the bottom. Several drainage pipes are evenly arranged along the circumference of the energy-concentrating chamber. One end of the drainage pipe is connected to the energy-concentrating chamber, and the opening of the other end faces downward, so as to introduce outside air into the energy-concentrating chamber.

Images