A zero-energy high-turbidity wastewater pretreatment device and method thereof

Abstract

The application discloses a zero-energy-consumption high-turbidity wastewater pretreatment device and a method thereof. The device can be arranged in multiple sets along a wastewater pretreatment channel, each set comprising an anode iron net, a cathode module and a trash screen. The anode iron net, the cathode module and the trash screen slot are arranged on the side wall of the channel. The closed hollow cavity volume of the rotating shaft of the cathode module, the size and the weight of the cathode module are set, so that the cathode module floats on the water surface of the wastewater and rises and falls with the water level change, and the lifting equipment is omitted. The cathode module is driven to rotate by the water flow, the wastewater is stirred by the rotation of the cathode module, the stirring equipment is omitted, and the energy consumption of lifting and stirring is realized. The electric energy generated between the cathode and the anode is collected and supplied to other small-load electrical appliances in the device, such as lighting, water quality detection instruments and flow monitoring instruments, and the device does not depend on external electric energy.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of sewage treatment, and particularly relates to a wastewater treatment device and a wastewater treatment method. BACKGROUND

[0002] High-turbidity wastewater refers to wastewater with high concentration of suspended pollutants. In urban life, landfill leachate, chemical and textile raw water, and wastewater with high algal content all belong to high-turbidity wastewater. High-turbidity wastewater has a huge impact on the natural environment and human life. High-turbidity water absorbs more solar heat, thereby exacerbating the greenhouse effect; high-turbidity water absorbs more oxygen, affecting the survival of aquatic organisms; suspended particles scatter sunlight, reducing the photosynthesis of aquatic plants, etc.

[0003] In the prior art, the pretreatment of high-turbidity wastewater requires a large amount of energy consumption. For example, a petrochemical wastewater treatment device with sufficient coagulation disclosed in Publication No. CN106587310A discloses that a lifting mechanism is arranged at the top of the tank body, and stirring paddles are fixed to the upper and lower ends of the fixed head. A filtration mechanism and antimony-containing metal wastewater filtration treatment device disclosed in Publication No. CN219117237U discloses that a lifting piece, a stirring assembly, and a filter piece are included. A coking wastewater treatment equipment disclosed in Publication No. CN118145769A discloses that a settling tank, a stirring device, and a lifting assembly are included. In these three technologies, lifting devices and stirring devices are used, which consume a large amount of energy. SUMMARY

[0004] The purpose of the present application is to overcome the technical problem of high energy consumption in the prior art when treating high-turbidity wastewater, and to provide a zero-energy-consumption high-turbidity wastewater purification device and method.

[0005] To solve the above technical problems, a zero-energy-consumption high-turbidity wastewater pretreatment device of the present application is implemented as follows:

[0006] The device is arranged in multiple sets along the wastewater pretreatment channel. The channel has flowing high-turbidity wastewater, and water quality detection instruments and flow monitoring instruments are arranged upstream in the direction of wastewater flow. Each set of the device includes an anode iron mesh, an adjustable resistor, a cathode module, and a trash screen. The channel side wall is provided with a slot, and the anode iron mesh, the cathode module, and the trash screen are inserted into the slot and in contact with the high-turbidity wastewater. The cathode module floats on the surface of the high-turbidity wastewater and is connected to the slot by sliding and rotating. The anode iron mesh is electrically connected to the cathode module through the adjustable resistor, forming a primary battery circuit.

[0007] Preferably, the slots of each set of devices are arranged in the order of the first anode iron mesh slot, the cathode module slot, the second anode iron mesh slot and the trash screen slot from upstream to downstream along the direction of wastewater flow, the cathode module is inserted into the cathode module slot, the two anode iron meshes are respectively inserted into the first anode iron mesh slot and the second anode iron mesh slot, and the trash screen is inserted into the trash screen slot.

[0008] The two opposite side walls of the cathode module slot are provided with conductive strips, and the conductive strips extend to the top surface of the cathode module slot.

[0009] Preferably, the cathode module comprises a roller-pressed cathode plate, a rotating shaft and a rotating shaft end.

[0010] The roller-pressed cathode plate is made of a layering and rolling of capacitive carbon powder, stainless steel mesh and conductive carbon powder into different shapes, the roller-pressed cathode plate further comprises a wire electrically connected to the stainless steel mesh, the number of the roller-pressed cathode plates is at least two and is circumferentially and uniformly distributed on the radial circumferential surface of the rotating shaft and fixedly connected to the circumferential surface of the rotating shaft, and the length of the roller-pressed cathode plate is slightly shorter than the axial length of the rotating shaft.

[0011] The rotating shaft end is made of a friction-resistant material, the outer surface of the rotating shaft end is fixedly connected with a conductive ring in the circumferential direction, the rotating shaft end is inserted into the cathode module slot, and after being inserted, the conductive strips on the two side walls abut against the conductive ring.

[0012] The rotating shaft is a closed hollow structure, and a terminal post is further fixedly connected to the circumferential surface of the rotating shaft, the terminal post comprises an A end above the surface of the rotating shaft and a B end below the surface of the rotating shaft, the B end is electrically connected to the conductive ring through a conductive wire embedded below the surface of the rotating shaft and the rotating shaft end, and the A end is electrically connected to the wire.

[0013] Preferably, the roller-pressed cathode plate is a rectangular flat plate.

[0014] Preferably, the roller-pressed cathode plate comprises a flat plate and a bent plate fixedly connected in sequence along the width direction of the roller-pressed cathode plate, wherein the flat plate end is fixedly connected to the rotating shaft, and the directions of the plurality of bent plates are consistent.

[0015] Preferably, the plurality of roller-pressed cathode plates are circumferentially and uniformly distributed along the rotating shaft and parallel to the axis of the rotating shaft.

[0016] Preferably, the roller-pressed cathode plates are spirally wound on the circumferential surface of the rotating shaft, and the end surface of the roller-pressed cathode plate is rectangular or arc-shaped as viewed along the axial direction of the rotating shaft.

[0017] Preferably, the trash screen has an arch-shaped structure as viewed from above, and the convex direction thereof faces upstream.

[0018] The high-turbidity wastewater pretreatment method based on the above-mentioned zero-energy-consumption high-turbidity wastewater pretreatment device comprises the following steps:

[0019] Step 1, install wastewater pretreatment device: the cathode module is inserted into the cathode module slot, ensuring that the conductive strip abuts the conductive ring; the first anode iron mesh is inserted into the first anode iron mesh slot, and the second anode iron mesh is inserted into the second anode iron mesh slot; the trash screen is inserted into the trash screen slot.

[0020] Step 2, circuit connection:

[0021] Step 2-1, primary cell circuit connection: the iron mesh of the two anode iron meshes is electrically connected to the input end of the adjustable resistance; the output end of the adjustable resistance is electrically connected to the conductive strip on the top surface of the cathode module slot; the A end of the terminal post is electrically connected to the wire;

[0022] Step 2-2, power generation circuit connection: the conductive strip on the top surface of the cathode module slot and the iron mesh of the two anode iron meshes are respectively electrically connected to the positive and negative input ends of the controller; the controller is electrically connected to the battery; the battery is electrically connected to the inverter; the inverter is electrically connected to the switch; the switch is electrically connected to the electrical equipment.

[0023] Step 3, adjust the working state of the device:

[0024] Step 3-1, detection: in the wastewater upstream of the channel, water quality detection instruments and flow monitoring instruments are set to detect the turbidity of the wastewater and obtain the turbidity value q of the wastewater; the flow of the wastewater is detected to obtain the flow value Q of the wastewater;

[0025] Step 3-2, set the resistance value of the adjustable resistance:

[0026] Using the detected wastewater turbidity q and flow Q, set the resistance value of the adjustable resistance to control the production of coagulant;

[0027] Step 4, wastewater treatment: the anode iron mesh side produces coagulant containing iron ions, ferrous ions and iron hydroxide, which has a net trapping effect on suspended solids and macromolecular organic matter in high-turbidity wastewater, causing them to coagulate and settle, forming coagulum;

[0028] Step 5, power generation: while the wastewater is being treated, an oxygen reduction reaction occurs on the roller-pressed cathode plate side, the primary cell loop generates electricity, and electrical energy is provided to the electrical equipment;

[0029] Step 6, trash blocking and cleaning: the coagulum is intercepted by the trash screen; the trash screen is periodically retracted and replaced, and the coagulum on the screen is cleaned.

[0030] In step 3-2, the resistance value of the adjustable resistance is calculated as follows:

[0031] R=(U×0.5×MFe×t) / [(0.024×q×Q×t +8.133)×F]

[0032] In the above formula, U is the voltage across the adjustable resistor (unit: V), 0.5 is the stoichiometric number (electron stoichiometric relationship between Fe and Fe2+, 1 mol of electrons corresponds to 0.5 mol of Fe), MFe is the molar mass of iron (unit: 56 g / mol), t is the coagulation time (unit: s), q is the wastewater turbidity (unit: NTU), Q is the wastewater flow (unit: m3 / s) Wastewater flow is equal to the product of wastewater flow rate and cross-sectional area, F is Faraday's constant (unit: 96485 C / mol).

[0033] When the coagulation time is 3h, the sedimentation effect is the most sufficient, so the hydraulic retention time is assumed to be t=3h, i.e. t=10800s, and further deduced as:

[0034] R=(U×5400×MFe) / [(259.2×q×Q+8.133)×F]

[0035] The beneficial effects of the present application compared with the prior art are:

[0036] 1. Due to the setting of the closed hollow cavity volume of the rotating shaft, the size and weight of the cathode module, the cathode module floats on the surface of the wastewater, and the lifting equipment is saved; the water flow drives the rotation of the cathode module, and the wastewater is stirred by the rotation of the cathode module, so that the stirring equipment is saved, and the energy consumption of lifting and stirring is realized.

[0037] 2. Collect the electric energy generated between the cathode and the anode, and supply it to other small load electrical appliances in the device, such as lighting, water quality detection instruments and flow monitoring instruments, which do not rely on external electric energy. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 It is a schematic diagram of a pretreatment channel without installing a wastewater pretreatment device;

[0039] Figure 2 It is a general layout diagram of the present application in a pretreatment channel;

[0040] Figure 3 It is a position relationship diagram of the conductive ring and the conductive strip after the cathode module is inserted into the cathode module slot;

[0041] Figure 4 It is a composition diagram of the rolled cathode plate;

[0042] Figure 5 It is a circuit block diagram of the original battery;

[0043] Figure 6 It is a circuit block diagram of electricity generation;

[0044] Figure 7 It is a schematic diagram of the cathode module of Example 1;

[0045] Figure 8 Schematic diagram of cathode module for example two;

[0046] Figure 9 Schematic diagram of cathode module for example three;

[0047] Figure 10 Schematic diagram of arched trash screen structure;

[0048] Figure 11 Schematic diagram of arched trash screen after installation;

[0049] Reference signs:

[0050] 1, channel; 11, cathode module slot; 111, conductive strip; 121, first anode iron screen slot; 122, second anode iron screen slot; 13, trash screen slot;

[0051] 2, cathode module; 21, roller pressed cathode plate; 211, capacitive carbon powder; 212, stainless steel mesh; 213, conductive carbon powder; 214, wire; 22, rotating shaft; 221, terminal post; 23, rotating shaft end; 231, conductive ring; 24, lifting ring;

[0052] 3, anode iron screen;

[0053] 4, trash screen. DETAILED DESCRIPTION

[0054] The application is based on the improvement of high turbidity wastewater pretreatment device. The high turbidity wastewater pretreatment device is arranged along the wastewater pretreatment channel. There are multiple sets of the device in the channel. There is flowing high turbidity wastewater in the channel. Water quality detection instrument and flow monitoring instrument are arranged on the upstream of the wastewater flow direction. Each set of the device includes anode iron screen, adjustable resistor, cathode module and trash screen. Slot is arranged on the side wall of the channel. The anode iron screen, the cathode module and the trash screen are inserted into the slot and contact with the high turbidity wastewater. The cathode module floats on the surface of the high turbidity wastewater and is connected with the slot through sliding and rotating. The anode iron screen is electrically connected with the cathode module through the adjustable resistor to form a primary battery circuit.

[0055] When the anode iron screen of the wastewater pretreatment device contacts with the high turbidity wastewater, the high turbidity wastewater will be used as electrolyte solution. Oxidation reaction occurs in the anode iron screen to generate coagulant containing iron ion, ferrous ion and iron hydroxide. The coagulant can coagulate and settle the suspended matter and macromolecular organic matter in the high turbidity wastewater to reduce the concentration of suspended pollutants. The main body of the cathode module is roller pressed cathode plate. The roller pressed cathode plate is made by laminating and rolling stainless steel mesh, conductive carbon powder and capacitive carbon powder. The stainless steel mesh is connected with the adjustable resistor through the wire. Oxygen in the air passes through the conductive carbon powder on the cathode module and then reduction reaction occurs at the stainless steel mesh.

[0056] The application will be described in further detail below with reference to the drawings and specific embodiments.

[0057] Please refer to Figures 1-3 , Figure 1 The channel 1 without a wastewater pretreatment device is shown in FIG. 1. A pair of insertion slots are formed on the opposite side walls of the channel 1 from upstream to downstream, which are a first anode iron mesh insertion slot 121, a cathode module insertion slot 11, a second anode iron mesh insertion slot 122, and a trash screen insertion slot 13.

[0058] Please refer to Figures 1-3 , the conductive strip 111 is arranged on the opposite side walls of the cathode module insertion slot 11. The conductive strip 111 extends to the top surface of the cathode module insertion slot 11. The conductive strip 111 on the opposite side walls of the cathode module insertion slot 11 is fixedly connected to the wall surface, is flatly attached to the wall surface, and protrudes from the wall surface. The conductive strip 111 on the top surface of the cathode module insertion slot 11 can be flatly attached to the top surface and protrude from the wall surface, or can be raised at an acute angle with the top surface. When the conductive strip 111 is raised at an acute angle with the top surface, it is convenient to connect the lead wire and align the conductive ring 231 to be inserted into the cathode module.

[0059] The conductive strip 111 is made of stainless steel.

[0060] Please refer to Figure 2 , the main body of the anode iron mesh 3 is an iron mesh, which is inlaid in a semi-enclosed frame formed by the two side frames and the bottom frame. The two side frames are inserted into the first anode iron mesh insertion slot 121 and the second anode iron mesh insertion slot 122.

[0061] The anode iron mesh is preferably 6mm×6mm or 10mm×10mm grid, and the iron wire diameter is 0.6mm-0.8mm. As long as the water passing area is large enough, it does not affect the normal flow of wastewater, does not cause water stagnation, and facilitates the passage of generated coagulation.

[0062] The main body of the trash screen 4 is a net body made of ultra-high molecular weight polyethylene material. This material has corrosion resistance, good water permeability, and does not chemically react with water. The net body is inlaid in a fully enclosed frame formed by the upper, lower, left and right frames. The two side frames and the bottom frame are inserted into the trash screen insertion slot 13.

[0063] The trash screen 4 is preferably a 40-mesh screen, or a 30-mesh screen, which is beneficial to the capture of coagulation.

[0064] Please refer to Figure 2 , 3 and Figures 7-9 , the cathode module 2 is composed of a rolled cathode plate 21, a rotating shaft 22, and a rotating shaft end 23. The rolled cathode plate 21 is arranged on the circumferential surface of the rotating shaft 22. The rotating shaft 22 is a closed hollow structure. A pair of lifting rings 24 are arranged on the surfaces close to the two ends of the rotating shaft 22. The lifting rings 24 are used to cooperate with the hook-shaped lifting rod at the front end to lift or lower the cathode module 2.

[0065] The rotating shaft 22 is fixed with a terminal post 221 on the circumferential surface, the terminal post 221 includes an A end above the surface of the rotating shaft 22 and a B end below the surface of the rotating shaft 22, the B end is electrically connected with the conductive ring 231 through the conductive wire buried below the surface of the rotating shaft 22 and the rotating shaft end 23, and the A end is used for electrically connecting with the wire 214. Figure 3 The dashed line indicates that when the buried cathode module 2 is manufactured, the conductive wire is buried below the surface of the rotating shaft (22) and the rotating shaft end (23) in advance.

[0066] The circumferential surface of the rotating shaft end 23 is fixedly connected with the conductive ring 231, the circumferential surface of the rotating shaft end 23 is provided with a groove, the groove width is matched with the diameter of the conductive strip 111, and the conductive ring 231 is embedded in the groove; the conductive ring 231 is made of stainless steel.

[0067] Please refer to Figure 3 , Figure 3 After the cathode module 2 is inserted into the cathode module slot 11, the position relationship diagram of the conductive ring and the conductive strip, after the cathode module 2 is inserted into the cathode module slot 11, it is ensured that the conductive strip (111) and the conductive ring (231) are closely abutted.

[0068] Through the setting of the volume of the closed hollow cavity of the rotating shaft 22, the size and the weight of the cathode module 2, the cathode module 2 is floated on the water surface of the wastewater, and the surface is lifted and lowered with the change of the water level, and the lifting equipment is saved.

[0069] The cathode module 2 is inserted into the cathode module slot 11, when inserted, the rotating shaft end 23 at both ends is inserted into the corresponding cathode module slot 11 on the two side walls of the channel, the rotating shaft 22 and the roller pressing cathode plate 21 arranged on the circumferential surface of the rotating shaft 22 are located between the two side walls of the channel, and the conductive strip 111 on the cathode module slot 11 is matched with the groove of the rotating shaft end 23, the conductive strip 111 is abutted with the conductive ring 231, the flowing wastewater impacts the roller pressing cathode plate 21 to drive the cathode module 2 to rotate, the conductive strip 111 and the conductive ring 231 are slidingly connected, when there is current in the circuit, the conductive strip 111 and the conductive ring 231 are electrically connected.

[0070] Because of the uneven distribution of water in the channel, the flow rate of water is too fast, which leads to the fact that the coagulant containing iron ions, ferrous ions and iron hydroxide produced by the anode iron mesh 3 cannot fully contact and mix with the suspended solids and macromolecular organic matter in the high turbidity wastewater, reducing the coagulation effect; the rotating cathode module 2 can not only play a role in stirring the wastewater, but also slow down the flow rate of the water, so that the coagulant fully contacts and mixes with the high turbidity wastewater; the rotating cathode module 2 can also increase the oxygen content of the wastewater; in order to make sufficient oxygen contact with the cathode module 2 and have sufficient residence time, the rotating speed of the cathode module 2 cannot be too fast, and it is appropriate to rotate at a speed of 1-3 revolutions per minute; the end 23 of the rotating shaft is made of a friction-resistant material, such as hard rubber.

[0071] Please refer to Figure 4 , the roller-pressed cathode plate 21 includes a capacitor carbon powder 211, a stainless steel mesh 212, a conductive carbon powder 213 and a wire 214; the stainless steel mesh 212 and the wire 214 are electrically connected, and the capacitor carbon powder 211 and the conductive carbon powder 213 are wrapped in the middle of the stainless steel mesh 212, and the roller-pressed cathode plate 21 is formed by rolling, which can be rolled into different shapes according to actual needs, and the inside can be a single unit or a plurality of identical units integrated. If it is a plurality of identical units integrated, the wire 214 of each unit is respectively electrically connected with a total wire, and the total wire is electrically connected with the A end of the terminal post. The conductive carbon powder 211 functions to prevent water and allow air to pass through, so that the capacitor carbon powder 211 can fully contact with oxygen; oxygen can fully contact with the electrons transmitted from the anode iron mesh 3 and the hydrogen ions penetrated from the solution under the catalytic action of the capacitor carbon powder 211 to generate an oxygen reduction reaction.

[0072] The amount of coagulant produced by the anode iron mesh 3 is not suitable for being too much or too little, and the amount of coagulant should be adjusted according to the turbidity and flow rate of the high turbidity wastewater; the adjustable resistor functions to adjust the resistance value according to the water quality and flow rate of the high turbidity wastewater under the condition that water quality detection instruments and flow rate monitoring instruments are arranged on the upstream of the channel, control the anode reaction rate, and adjust the amount of coagulant.

[0073] Please refer to Figure 5 , Figure 5 is a circuit diagram of a primary cell, and the adjustable resistor is electrically connected between the anode iron mesh 3 of the high turbidity wastewater and the roller-pressed cathode plate 21 to form a primary cell (the arrow in the figure indicates the direction of electron flow in the primary cell).

[0074] The components through which the electrons generated by the anode flow in sequence are: the anode iron mesh 3, the adjustable resistor, the conductive strip 111, the conductive ring 231, the pre-buried conductive wire, the terminal post 221, the wire 214 and the roller-pressed cathode plate 21.

[0075] Please refer to Figure 6 , Figure 6The circuit block diagram for generating electricity; the conductive strip 111 on the top surface of the cathode module slot 11 and the two anode iron meshes 3 are respectively electrically connected to the positive and negative input terminals of the controller; the controller is electrically connected to the battery; the battery is electrically connected to the inverter; the inverter is electrically connected to the switch; the switch is electrically connected to the electrical equipment; the primary battery charges the battery through the controller, and the battery supplies power to the electrical equipment through the inverter and the switch.

[0076] Each set of devices can be configured with a set of controllers, inverters and batteries, or multiple sets of devices can share a set of controllers, inverters and batteries. Embodiment 1:

[0077] Please refer to Figure 2 and Figure 7 The roll-pressed cathode plate 21 of the embodiment is a rectangular flat plate, and a plurality of roll-pressed cathode plates 21 are uniformly distributed in the circumferential surface of the shaft 22. The width direction of the roll-pressed cathode plate 21 is consistent with the radial direction of the shaft 22, and is fixedly connected with the circumferential surface of the shaft 22. The length of the roll-pressed cathode plate 21 is slightly shorter than the axial length of the shaft 22.

[0078] The number of roll-pressed cathode plates 21 is determined according to the turbidity and flow of high-turbidity wastewater, the power consumption of electrical equipment, etc. However, in order to balance the rotation of the cathode module 2, there must be at least two roll-pressed cathode plates 21. In this embodiment, the number of roll-pressed cathode plates 21 is four.

[0079] The flat plate type roll-pressed cathode plate in this embodiment has the advantage of being easy to manufacture. Embodiment 2:

[0080] Please refer to Figure 8 The difference between this embodiment and Embodiment 1 is that one end of the roll-pressed cathode plate 21 in the width direction is a straight plate, and the other end is a curved plate. The overall shape is an arc-shaped plate. Compared with the roll-pressed cathode plate 21 of Embodiment 1, the roll-pressed cathode plate 21 of the arc-shaped plate with the same flow rate, the same number and the same cross-sectional area generates a larger rotational torque than the roll-pressed cathode plate 21 of the flat plate.

[0081] When the roll-pressed cathode plate 21 is fixedly connected with the circumferential surface of the shaft 22, the straight plate end of the roll-pressed cathode plate 21 is fixedly connected with the surface of the shaft 22, and the bending directions of each roll-pressed cathode plate 21 are consistent.

[0082] In this embodiment, the roll-pressed cathode plate 21 is three.

[0083] Except for the above-mentioned differences, the rest is the same as Embodiment 1, which will not be described in detail. Embodiment 3:

[0084] Please refer to Figure 9The difference between the embodiment and the above two embodiments is that the outer shape of the roll-pressed cathode plate 21 is a curved plate spirally wound on the circumferential surface of the rotating shaft 22. The curved plate has the advantage that the coagulant and the suspended pollutants in the wastewater are not easily adsorbed on the curved plate to form coagulants.

[0085] In the embodiment, the roll-pressed cathode plate 21 is two.

[0086] In addition to the above differences, the rest is the same as the first embodiment, and will not be repeated.

[0087] In addition, as shown in Figure 2 , the trash screen 4 is a straight plate. In order to facilitate the removal of coagulants on the trash screen 4, it is better to use an arched trash screen 4.

[0088] The arched trash screen 4 is described in Figure 10 and Figure 11 When the arched trash screen 4 is installed in the channel 1, the convex direction of the arched trash screen 4 faces upstream of the wastewater flow direction. Part of the coagulants is driven by the water flow and flows along the arched surface to both sides close to the side wall of the channel 1, facilitating the regular salvage and removal of the coagulants by the management personnel using tools.

[0089] The zero-energy high-turbidity wastewater pretreatment method based on the device of the application comprises the following steps:

[0090] Step 1, installing the wastewater pretreatment device: the cathode module 2 is inserted into the cathode module slot 11; the first anode iron screen 3 is inserted into the first anode iron screen slot 121, and the second anode iron screen 3 is inserted into the second anode iron screen slot 122; and the trash screen 4 is inserted into the trash screen slot 13.

[0091] Step 2, circuit connection: the iron screen of the two anode iron screens 3 is electrically connected with the input end of the adjustable resistance; the wire 214 of the cathode module 2 is electrically connected with the output end of the adjustable resistance; the wire 214 of the cathode module 2 and the iron screen of the two anode iron screens 3 are respectively electrically connected with the positive and negative input ends of the controller; the controller is electrically connected with the storage battery; the storage battery is electrically connected with the inverter; the inverter is electrically connected with the switch; and the switch is electrically connected with the electric equipment.

[0092] Step 3, adjusting the working state of the device:

[0093] Step 3-1, detection: in the wastewater upstream of the channel, water quality detection instruments and flow monitoring instruments are arranged to detect the wastewater turbidity and obtain the wastewater turbidity value q; and the wastewater flow is detected to obtain the wastewater flow value Q;

[0094] Step 3-2, setting the resistance value of the adjustable resistance:

[0095] The resistance value of the adjustable resistance is set by using the detected wastewater turbidity q and flow Q to control the yield of the coagulant.

[0096] Step 4, wastewater treatment: wastewater flows through the anode iron net and the cathode module, high turbidity wastewater as electrolyte solution, so that the anode iron net connected by wire, adjustable resistance and cathode module form a closed primary cell circuit; The anode iron net side spontaneously generates a coagulant containing iron ions, ferrous ions and iron hydroxide, which can capture suspended solids and macromolecular organic matter in high turbidity wastewater, allowing it to coagulate and settle, and when the coagulation time is 3h, the settling effect is most sufficient, forming a coagulum;

[0097] Step 5, power generation: while treating wastewater, an oxygen reduction reaction occurs on the roller-pressed cathode plate side, the primary cell circuit generates electricity, and provides electrical energy to the electrical equipment.

[0098] Step 6, pollution blocking and cleaning: the coagulum is intercepted by the pollution blocking net; The pollution blocking net is regularly retracted and replaced, and the coagulum on the net is cleaned.

[0099] In step 3-2, the resistance value of the adjustable resistance is calculated by the following formula:

[0100] R=(U×0.5×MFe×t) / [(0.024×q×Q×t +8.133)×F]

[0101] In the above formula, U is the voltage between the two ends of the adjustable resistance (unit: V), 0.5 is the stoichiometric number (the electron stoichiometric relationship between Fe and Fe2+, 1 mol of electrons corresponds to 0.5 mol of Fe), MFe is the molar mass of iron (unit: 56 g / mol), t is the coagulation time (unit: s), q is the wastewater turbidity (unit: NTU), Q is the wastewater flow (unit: m / s) The wastewater flow is equal to the product of the wastewater flow rate and the cross-sectional area, and F is the Faraday constant (unit: 96485 C / mol). 3

[0102] When the coagulation time is 3h, the settling effect is most sufficient, so the hydraulic retention time is assumed to be t=3h, i.e. t=10800s, and further deduced as:

[0103] R=(U×5400×MFe) / [(259.2×q×Q+8.133)×F]

[0104] Therefore, only the wastewater turbidity and wastewater flow of the wastewater are required to set the resistance value of the adjustable resistance, so that the pollutants can be coagulated and settled efficiently.

[0105] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, and any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.​

Claims

1. A zero-energy high-turbidity wastewater pretreatment device, wherein multiple sets of the device are arranged along a wastewater pretreatment channel (1), the channel (1) contains flowing high-turbidity wastewater, and water quality testing instruments and flow monitoring instruments are installed upstream in the direction of wastewater flow, characterized in that, Each device includes an anode iron mesh (3), an adjustable resistor, a cathode module (2), and a debris screen (4). Slots are provided on the side wall of the channel (1). The anode iron mesh (3), cathode module (2), and debris screen (4) are inserted into the slots and come into contact with the high-turbidity wastewater. The cathode module (2) floats on the surface of the high-turbidity wastewater and is slidably and rotatably connected to the slot. The anode iron mesh (3) and the cathode module (2) are electrically connected through the adjustable resistor to form a galvanic cell circuit. The slots of each device, along the direction of wastewater flow from upstream to downstream, are the first anode iron mesh slot (121), the cathode module slot (11), the second anode iron mesh slot (122), and the debris screen slot (13). The cathode module (2) is inserted into the cathode module slot (11), the two anode iron meshes (3) are inserted into the first anode iron mesh slot (121) and the second anode iron mesh slot (122) respectively, and the debris screen (4) is inserted into the debris screen slot (13). Conductive strips (111) are provided on the opposite side walls of the cathode module slot (11), and the conductive strips (111) extend to the top surface of the side wall of the cathode module slot (11).

2. The zero-energy high-turbidity wastewater pretreatment device according to claim 1, characterized in that, The cathode module (2) includes a rolled cathode plate (21), a rotating shaft (22) and a rotating shaft end (23). The roll-pressed cathode plate (21) is formed by stacking and rolling capacitor carbon powder (211), stainless steel mesh (212) and conductive carbon powder (213) into different shapes. The roll-pressed cathode plate (21) also includes a wire (214) electrically connected to the stainless steel mesh (212). There are at least two roll-pressed cathode plates (21) and they are evenly distributed on the radial circumferential surface of the rotating shaft (22) and fixedly connected to the circumferential surface of the rotating shaft (22). The length of the roll-pressed cathode plate (21) is slightly shorter than the axial length of the rotating shaft (22). The shaft end (23) is made of abrasion resistant material. The outer surface of the shaft end (23) is fixedly connected to the conductive ring (231) along the circumferential direction. The shaft end (23) is inserted into the cathode module slot (11). After insertion, the conductive strips (111) on both sides abut against the conductive ring (231). The rotating shaft (22) is a closed hollow structure, and its peripheral surface is also fixed with a terminal (221). The terminal (221) includes an A end located above the surface of the rotating shaft (22) and a B end located below the surface of the rotating shaft (22). The B end is electrically connected to the conductive ring (231) through a conductive wire buried below the surface of the rotating shaft (22) and the end of the rotating shaft (23), and the A end is electrically connected to the wire (214).

3. The zero-energy high-turbidity wastewater pretreatment device according to claim 2, characterized in that, The roll-pressed cathode plate (21) is a rectangular flat plate.

4. The zero-energy high-turbidity wastewater pretreatment device according to claim 3, characterized in that, The roll-formed cathode plate (21) includes a flat plate and a bent plate that are fixedly connected in sequence along its width direction, wherein the end of the flat plate is fixedly connected to the rotating shaft (22); the multiple bent plates are oriented in the same direction.

5. The zero-energy high-turbidity wastewater pretreatment device according to claim 3 or 4, characterized in that, Multiple roller-pressed cathode plates (21) are evenly distributed around the circumference of the rotating shaft (22) and are parallel to the axis of the rotating shaft (22).

6. The zero-energy high-turbidity wastewater pretreatment device according to claim 2, characterized in that, The roller-pressed cathode plate (21) is spirally coiled around the circumferential surface of the rotating shaft (22); when viewed along the axial direction of the rotating shaft (22), the end face of the roller-pressed cathode plate (21) is rectangular or arc-shaped.

7. The zero-energy high-turbidity wastewater pretreatment device according to claim 2, characterized in that, The debris barrier (4) has an arched structure when viewed from above, with its protrusion facing upstream.

8. A method for pretreating high-turbidity wastewater using a zero-energy high-turbidity wastewater pretreatment device according to any one of claims 1-7, characterized in that: Includes the following steps: Step 1: Install the wastewater pretreatment device: Insert the cathode module (2) into the cathode module slot (11) and ensure that the conductive strip (111) abuts against the conductive ring (231); insert the first anode iron mesh (3) into the first anode iron mesh slot (121) and the second anode iron mesh (3) into the second anode iron mesh slot (122); insert the trash net (4) into the trash net slot (13); Step 2, Circuit Connection: Step 2-1, Connection of the primary battery circuit: The iron mesh of the two anode iron mesh (3) is electrically connected to the input end of the adjustable resistor; the output end of the adjustable resistor is electrically connected to the conductive strip (111) on the top surface of the cathode module slot (11); the A end of the terminal (221) is electrically connected to the wire (214). Step 2-2, Power generation circuit connection: The conductive strip (111) on the top surface of the cathode module slot (11) and the iron mesh of the two anode iron meshes (3) are electrically connected to the positive and negative input terminals of the controller respectively; the controller is electrically connected to the storage battery; the storage battery is electrically connected to the inverter; the inverter is electrically connected to the switch; the switch is electrically connected to the electrical equipment. Step 3: Adjust the device's operating status: Step 3-1, Detection: In the upstream wastewater of the channel, set up water quality testing instruments and flow monitoring instruments to detect the turbidity of the wastewater and obtain the turbidity value q; detect the wastewater flow rate and obtain the wastewater flow rate value Q. Step 3-2: Set the resistance value of the adjustable resistor: By using the detected wastewater turbidity q and flow rate Q, the resistance value of the adjustable resistor is set to control the coagulant production. Step 4, wastewater treatment: A coagulant containing iron ions, ferrous ions and iron hydroxide is generated on the anode iron mesh (3) side. The coagulant has a netting effect on suspended solids and macromolecular organic matter in high turbidity wastewater, causing them to coagulate and settle, forming coagulated matter. Step 5, power generation: While treating wastewater, an oxygen reduction reaction occurs on the side of the roller-pressed cathode plate (21), generating electricity in the galvanic cell circuit to provide power to the electrical equipment. Step 6, Contamination Interception and Cleaning: Concrete is intercepted by a contamination net; the contamination net is periodically removed and replaced, and the concrete on the net is cleaned.

9. The method for pretreatment of high-turbidity wastewater according to claim 8, characterized in that: The formula for calculating the resistance value of the adjustable resistor in step 3-2 is as follows: R=(U×0.5×M Fe ×t) / [(0.024×q×Q×t +8.133)×F]; In the above formula, U is the voltage across the adjustable resistor, in volts (V); 0.5 is the stoichiometric coefficient, representing the electron stoichiometry between Fe and Fe²⁺, where 1 mol of electrons corresponds to 0.5 mol of Fe; M Fe t represents the molar mass of iron, in g / mol; t represents the coagulation time, in seconds. q represents wastewater turbidity, in NTU; Q represents wastewater flow rate, in m³ / s. 3 / s, wastewater flow rate equals the product of wastewater velocity and cross-sectional area; F is the Faraday constant, unit: C / mol; When the coagulation time is 3 hours, the settling effect is most complete. Therefore, assuming the hydraulic retention time is t = 3 hours, or t = 10800 seconds, we can further deduce: R=(U×5400×M Fe ) / [(259.2×q×Q+8.133)×F]。

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