An environmentally friendly filtration device for municipal drainage

Abstract

This invention discloses an environmentally friendly filtration device for municipal drainage, comprising an influent pretreatment module for preliminary purification of raw water, a multi-stage composite filtration module for progressive interception and deep purification of pollutants through three-stage filtration, a sludge treatment module for reducing and rendering harmless the sludge generated during filtration, an intelligent control module for dynamically optimizing equipment operating parameters based on sensor data, and an energy recovery module for converting water flow potential energy and thermal energy into electrical or thermal energy for the device's own use. This invention achieves efficient pollution interception, low energy consumption, and resource recycling through integrated modular design. The multi-stage composite filtration module employs a three-stage synergistic mechanism of "cyclone separation - bio-adsorption - membrane filtration," combined with the dynamic parameter optimization of the intelligent control module and the kinetic / thermal energy conversion of the energy recovery module, solving the problems of low filtration efficiency, high energy consumption, and severe secondary pollution associated with traditional equipment.

Description

Technical Field

[0001] This invention relates to the field of municipal drainage treatment equipment technology, and in particular to an environmentally friendly filtration device for municipal drainage. Background Technology

[0002] With the acceleration of urbanization, municipal drainage systems face challenges such as increasingly complex water quality, large flow fluctuations, and high treatment costs. Existing filtration equipment uses a single filter medium, is prone to clogging, and has poor interception effect on micro-pollutants. At the same time, it relies on mechanical pressure backwashing, which can easily cause secondary pollution from backwash wastewater. Furthermore, the backwashing cycle is short and the frequency is high, resulting in a large workload for operation and maintenance. Therefore, this invention proposes an environmentally friendly filtration device for municipal drainage to solve the problems existing in the prior art. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to propose an environmentally friendly filtration device for municipal drainage. This device, through integrated modular design, achieves efficient interception of pollutants, low-energy operation, and resource recycling. The multi-stage composite filtration module adopts a three-stage synergistic mechanism of "cyclone separation - bio-adsorption - membrane filtration," combined with the dynamic parameter optimization of the intelligent control module and the kinetic / thermal energy conversion of the energy recovery module, thus solving the problems of low filtration efficiency, high energy consumption, and serious secondary pollution of traditional equipment.

[0004] To achieve the objectives of this invention, the invention is implemented through the following technical solution: an environmentally friendly filtration device for municipal drainage, comprising an influent pretreatment module, a multi-stage composite filtration module, a sludge treatment module, an intelligent control module, and an energy recovery module. The influent pretreatment module is used to perform preliminary purification of raw water. The multi-stage composite filtration module performs step-by-step interception and deep purification of pollutants through three-stage filtration. The sludge treatment module is used to reduce and render harmless the sludge generated during filtration. The intelligent control module dynamically optimizes the device's operating parameters based on sensor data. The energy recovery module is used to convert the potential energy and thermal energy of the water flow into electrical energy or thermal energy for the device's own use.

[0005] Further improvements are made in that: the water inlet pretreatment module includes a grid unit, a cyclone sand removal unit, and an oil separator unit arranged sequentially along the water flow direction. The grid unit is a stepped stainless steel grid with a grid gap of 5-10mm, used to intercept large particles of impurities. The cyclone sand removal unit forms a cyclone field by having water enter the cyclone sand remover tangentially, and uses centrifugal force to separate inorganic sand particles, which are then discharged from the sand discharge port at the bottom of the cyclone sand remover. The oil separator unit is based on a V-shaped oil-collecting plate, which uses surface tension to collect floating oil and collects it through an oil collection pipeline.

[0006] Further improvements are made in that: the multi-stage composite filtration module includes a cyclone separation unit, a bio-adsorption unit, and a membrane filtration unit arranged in series along the water flow direction. Each unit has a built-in pressure sensor and a backwashing interface. The cyclone separation unit uses a gradually expanding cyclone tube to remove suspended solids into the sludge treatment module, and the clean water overflows into the bio-adsorption unit. The bio-adsorption unit uses a composite packing material of modified biochar and ceramsite combined with aerobic microorganisms to bio-adsorb clean water. The membrane filtration unit uses a PVDF hollow fiber ultrafiltration membrane to further filter the clean water after microbial adsorption.

[0007] A further improvement is that the modified biochar is prepared by magnetizing biochar with Fe3O4, and has a specific surface area ≥800m². 2 / g; the ceramsite has a particle size of 3-5mm and a porosity of ≥60%; the aerobic microorganisms are Pseudomonas and Bacillus.

[0008] A further improvement is that the PVDF hollow fiber ultrafiltration membrane has a pore size of 0.01-0.1μm and is arranged at an inclination angle of 30°-45°, and its surface is coated with a polyvinyl alcohol hydrophilic coating.

[0009] Further improvements are made in that: the sludge treatment module is connected to the multi-stage composite filtration module, which includes a sludge thickening unit, a plate and frame filter press unit, and a drying unit arranged in sequence. The sludge thickening unit reduces the sludge moisture content by gravity settling in the sludge thickening tank, with a moisture content ≤95%. The plate and frame filter press unit uses a plate and frame filter press to press the settled sludge into sludge cakes using a high-pressure diaphragm pressing, with a moisture content ≤60%. The drying unit uses the waste heat from the energy recovery module to perform low-temperature drying treatment on the sludge cakes, with a moisture content ≤30%.

[0010] Further improvements are made in the following aspects: The intelligent control module includes a PLC control unit, a multi-parameter sensing unit, a variable frequency water pump, an electric regulating valve, and a human-machine interaction unit. The PLC control unit is used for the overall coordinated control of the various modules of the device. The multi-parameter sensing unit collects data on influent flow rate, turbidity, pressure difference across the membrane in the multi-stage composite filtration module, and water temperature in real time through multi-parameter sensors, specifically including a flow sensor, a turbidity sensor, a pressure sensor, and a water temperature sensor. The variable frequency water pump dynamically adjusts the water pressure according to the influent flow rate. The electric regulating valve is used to adjust the flow rate, pressure, and flow direction of water and air in each pipeline. The human-machine interaction unit is used for the visual interaction of the operator.

[0011] Further improvements are made in that: the energy recovery module includes a micro hydropower generation unit, a heat exchange unit, and an energy storage unit. The micro hydropower generation unit generates electricity by utilizing the potential energy of the overflow water in the multi-stage composite filtration module through a micro hydropower generator. The heat exchange unit transfers the heat energy from the temperature difference between the membrane filtration product water and the influent water of the multi-stage composite filtration module to the sludge treatment module based on a plate heat exchanger. The energy storage unit stores the electrical energy generated by the micro hydropower generation unit based on an energy storage battery, which is then used by the intelligent control module, sensors, and low-power devices.

[0012] The beneficial effects of this invention are as follows: This invention uses an influent pretreatment module to intercept large particulate impurities, inorganic sand, and floating oil in stages, which greatly reduces the subsequent load; a multi-stage composite filtration module removes large suspended solids, degrades organic matter and complexes heavy metals, and intercepts bacteria, viruses, and microplastics, achieving deep purification through three-stage synergy; a sludge treatment module achieves sludge reduction and resource utilization; an intelligent control module relies on a PLC controller and flow / turbidity / differential pressure sensors to monitor data in real time, effectively improving operational stability and energy efficiency; and an energy recovery module can recover thermal energy from temperature differences and store electrical energy in an energy storage battery, achieving ≥30% self-powered equipment.

[0013] This invention combines the advantages of high-efficiency purification, stable operation, low energy consumption, sludge resource utilization, and energy self-sufficiency, significantly improving the environmental friendliness and economy of municipal drainage treatment. Attached Figure Description

[0014] Figure 1 This is a diagram showing the connection architecture of the device modules of the present invention. Detailed Implementation

[0015] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0016] With the acceleration of urbanization, municipal drainage systems face challenges such as increasingly complex water quality (including silt, oil, organic matter, microplastics, etc.), large flow fluctuations, and high treatment costs. Existing filtration equipment has the following shortcomings:

[0017] Insufficient filtration efficiency: Single filter media (such as sand filters, filter screens) are prone to clogging and have poor retention effect on micro pollutants (such as microplastics and heavy metal ions);

[0018] High energy consumption and maintenance costs: It relies on mechanical pressurization or frequent backwashing, which generates secondary pollution from backwash wastewater. In addition, the backwashing cycle is short (usually 1-3 days), resulting in a large workload for operation and maintenance.

[0019] Resource waste: The energy (such as water flow potential energy and heat energy) and recyclable materials (such as oil and organic matter) in the filtration process are not utilized, which does not meet the green treatment requirements under the "dual carbon" target.

[0020] Based on the aforementioned defects, according to Figure 1 As shown, this embodiment provides an environmentally friendly filtration device for municipal drainage, including an influent pretreatment module, a multi-stage composite filtration module, a sludge treatment module, an intelligent control module, and an energy recovery module. All modules adopt a modular design, and each module can be detachably connected via flanges or quick-connect fittings.

[0021] The inlet water pretreatment module is used for preliminary purification of raw water, including a bar screen unit, a cyclone sand removal unit and an oil separator baffle unit arranged in sequence along the water flow direction;

[0022] The grid unit is a stepped stainless steel grid with a grid gap of 5-10mm, used to intercept large particles of impurities;

[0023] The cyclone sand removal unit uses a cyclone separator to create a swirling field by tangential water inlet, and uses centrifugal force to separate inorganic sand particles with a density greater than 2.65 g / cm³ and a particle size greater than 0.2 mm. The sand particles are periodically discharged through the bottom sand discharge port.

[0024] The oil separator unit is a V-shaped oil-collecting plate that uses surface tension to collect floating oil, which then enters the oil storage tank through the top oil collection pipe.

[0025] The multi-stage composite filtration module achieves progressive interception and deep purification of pollutants through three-stage filtration, including a cyclone separation unit, a bio-adsorption unit, and a membrane filtration unit connected in series along the water flow direction. Each stage is equipped with a pressure sensor and a backwashing interface.

[0026] The cyclone separation unit uses a gradually expanding cyclone tube with a diameter of 1.5m and a cone angle of 25°. Raw water enters tangentially at a flow velocity of 4m / s and a density of 2.65g / cm³. 3 Suspended solids enter the sludge treatment module through the bottom sludge discharge port, while clean water enters the biological adsorption unit from the top overflow pipe.

[0027] Biosorption units are filled with modified biochar-ceramsite composite filler, wherein the biochar is magnetized with Fe3O4 and has a specific surface area ≥800 m². 2 / g, the ceramsite particle size is 3-5mm, and the porosity is ≥60%; the biosorption unit is also inoculated with aerobic microorganisms, including Pseudomonas and Bacillus; it complexes heavy metal ions (such as Pb) through biosorption. 2+ Cd 2+ And removes COD, ammonia nitrogen, and organic matter through biodegradation;

[0028] The membrane filtration unit uses a PVDF hollow fiber ultrafiltration membrane with a pore size of 0.1μm. The membrane module is arranged at an angle of 30° and the membrane surface is coated with a hydrophilic coating, which is a polyvinyl alcohol coating. It can retain bacteria, viruses, microplastics with a particle size >0.1μm and residual suspended solids, with effluent SS≤10mg / L and COD≤50mg / L.

[0029] The three-stage filtration synergy mechanism of the multi-stage composite filtration module is as follows: the cyclone separation unit removes large particulate suspended solids to reduce the load on the bio-adsorption unit, the bio-adsorption unit degrades organic matter to extend the life of the membrane filtration unit, and the membrane filtration unit ensures that the effluent meets the standards.

[0030] The sludge treatment module reduces and renders harmless the sludge produced by filtration. It is connected to the multi-stage composite filtration module, which includes a sludge thickening unit, a plate and frame filter press unit, and a drying unit arranged in sequence.

[0031] The sludge thickening unit utilizes a sludge thickening tank to reduce the sludge moisture content from 99% to 95% through gravity settling.

[0032] The plate and frame filter press unit uses a plate and frame filter press with high-pressure diaphragm pressing at a pressure of 1.2 MPa to reduce the moisture content of the sludge to below 60% and form a sludge cake.

[0033] The drying unit utilizes the waste heat from the energy recovery module for low-temperature drying at 50°C, resulting in a final sludge moisture content of ≤30%. The dried sludge cake can be used as landscaping soil or building material raw material. The waste heat sources include the heat energy output from the heat exchanger of the energy recovery module and the heat energy from the temperature difference between the membrane filtration permeate and the influent.

[0034] The intelligent control module dynamically optimizes equipment operating parameters based on sensor data, including a PLC control unit, a multi-parameter sensing unit, a variable frequency water pump, an electric regulating valve, and a human-machine interaction unit;

[0035] The PLC control unit is used for the overall coordinated control of various modules of the device. The control logic includes: real-time acquisition of influent flow rate, turbidity, pressure difference across the membrane, and water temperature data; when the turbidity is >20 NTU or the pressure difference across the membrane is >0.05 MPa, the air-water combined backwashing program is started, first introducing compressed air to disturb the membrane surface for 30 seconds, and then introducing clean water to rinse for 60 seconds; the variable frequency pump speed is automatically adjusted based on the influent flow rate, and when the flow rate is <50% of the design value, the pump frequency is reduced to 30 Hz;

[0036] It also includes energy-saving optimization strategies: adjusting the membrane operating temperature through a temperature-membrane flux model and using the heat energy compensation of the energy recovery module to maintain stable membrane flux;

[0037] The multi-parameter sensing unit includes a flow sensor, a turbidity sensor, a pressure sensor, and a temperature sensor, which collects data on influent flow rate, turbidity, pressure difference across the membrane in the multi-stage composite filtration module, and water temperature in real time.

[0038] The variable frequency water pump dynamically adjusts its speed according to the inlet water flow to achieve "on-demand water supply" and reduce ineffective energy consumption. It receives data from the flow sensor through the PLC controller. When the inlet water flow is less than 50% of the design value, it automatically reduces the pump frequency (e.g., to 30Hz) to reduce motor power consumption. When the flow increases, the speed is increased synchronously to ensure stable inlet water pressure of the filter unit.

[0039] Electric regulating valves are used to regulate the flow rate, pressure, and direction of water and air in various pipelines. During normal filtration, they regulate the flow rate of inlet water distributed to each stage of the filtration unit to balance the load. During backwashing, they control the on / off state and flow rate of backwash water (or compressed air). For example, in combined air-water backwashing, the pneumatic valve is opened first to allow compressed air to flow for 30 seconds, and then the electric regulating valve is opened to allow clean water to flow for 60 seconds. In emergency situations, they can quickly cut off abnormal water flow, such as closing the inlet valve when the pressure difference of the membrane module is too high.

[0040] The human-machine interface (HMI) unit is used for visual interaction by operators. Its functions include data display, parameter setting, alarm prompts, and historical data query. Data display shows key parameters such as flow rate, turbidity, membrane pressure differential, and water temperature in real time. Parameter setting allows operators to set backwash trigger thresholds (e.g., turbidity > 20 NTU) and pump frequency lower limits. Alarm prompts push audible and visual alarms when equipment malfunctions (e.g., excessive pressure differential or sudden increase in energy consumption). Historical data query stores operational data (e.g., energy consumption curves and backwash records) for easy traceability and analysis.

[0041] The energy recovery module is coupled with the overall equipment to convert the potential energy and thermal energy of water flow into electrical energy or thermal energy for the equipment's own use. It includes a micro hydropower generation unit, a heat exchange unit, and an energy storage unit.

[0042] The micro hydroelectric power generation unit utilizes a micro hydroelectric generator installed at the overflow outlet of the cyclone separator unit, taking advantage of a water head of 2m and a flow rate of 0.1-0.5m³ / h. 3 The potential energy of the water flow per second drives a turbine to generate electricity, with an output power of 500-2000W;

[0043] The heat exchange unit utilizes the temperature difference between the membrane filtration product water and the influent water to transfer heat energy to the backwash water preheating or sludge drying process.

[0044] The energy storage unit stores electrical energy generated by the micro hydroelectric generator based on the energy storage battery, which is used by the intelligent control module, sensors and low-power devices. The device has a self-powering rate of ≥30%. The energy storage battery is a lithium battery pack, and its capacity is configured according to the average daily power generation of the micro hydroelectric generator and the low-power operation time of the device.

[0045] Taking a primary rainwater treatment project in a residential community as an example, this invention is implemented with the following inflow conditions: primary rainwater flow rate 0.3 m³ / h. 3 / s, SS=300mg / L, COD=150mg / L, containing a small amount of leaves, mud and oil;

[0046] Equipment installation: Assemble according to the aforementioned modules. The cyclone separation unit has a diameter of 1m, the biosorption unit packing height is 1.5m, and the membrane module area is 50m². 2 ;

[0047] Operational results: effluent SS = 8 mg / L, COD = 35 mg / L, meeting Class A standard; energy consumption 0.15 kWh / m³ 3 (Traditional equipment is 0.25kWh / m) 3 ); 5 kg of floating oil is recovered daily (for industrial lubrication), and 0.02 m³ of sludge is produced. 3 / d (moisture content 60%), after drying, is made into landscaping soil.

[0048] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An environmentally friendly filtration device for municipal drainage, characterized in that: The system includes an influent pretreatment module, a multi-stage composite filtration module, a sludge treatment module, an intelligent control module, and an energy recovery module. The influent pretreatment module is used to perform preliminary purification of raw water. The multi-stage composite filtration module intercepts and deeply purifies pollutants through three-stage filtration. The sludge treatment module is used to reduce and render harmless the sludge generated during filtration. The intelligent control module dynamically optimizes the equipment's operating parameters based on sensor data. The energy recovery module is used to convert the potential energy and thermal energy of the water flow into electrical or thermal energy for the equipment's own use.

2. The environmentally friendly filtration device for municipal drainage according to claim 1, characterized in that: The inlet water pretreatment module includes a grid unit, a cyclone sand removal unit, and an oil separator unit arranged sequentially along the water flow direction. The grid unit is a stepped stainless steel grid with a grid gap of 5-10mm, used to intercept large particles of impurities. The cyclone sand removal unit forms a cyclone field by having water enter the cyclone sand remover tangentially, and uses centrifugal force to separate inorganic sand particles, which are then discharged from the sand discharge port at the bottom of the cyclone sand remover. The oil separator unit is based on a V-shaped oil-collecting plate, which uses surface tension to collect floating oil and collects it through an oil collection pipeline.

3. The environmentally friendly filtration device for municipal drainage according to claim 1, characterized in that: The multi-stage composite filtration module includes a cyclone separation unit, a bio-adsorption unit, and a membrane filtration unit arranged in series along the water flow direction. Each unit has a built-in pressure sensor and backwashing interface. The cyclone separation unit uses a gradually expanding cyclone tube to remove suspended solids into the sludge treatment module, and the clean water overflows into the bio-adsorption unit. The bio-adsorption unit uses a composite packing material of modified biochar and ceramsite combined with aerobic microorganisms to bio-adsorb clean water. The membrane filtration unit uses a PVDF hollow fiber ultrafiltration membrane to further filter the clean water after microbial adsorption.

4. The environmentally friendly filtration device for municipal drainage according to claim 3, characterized in that: The modified biochar was prepared by magnetizing biochar with Fe3O4 and has a specific surface area ≥800 m². 2 / g; the ceramsite has a particle size of 3-5mm and a porosity of ≥60%; the aerobic microorganisms are Pseudomonas and Bacillus.

5. An environmentally friendly filtration device for municipal drainage according to claim 3, characterized in that: The PVDF hollow fiber ultrafiltration membrane has a pore size of 0.01-0.1μm and is arranged at an angle of 30°-45°. The surface is coated with a polyvinyl alcohol hydrophilic coating.

6. An environmentally friendly filtration device for municipal drainage according to claim 1, characterized in that: The sludge treatment module is connected to a multi-stage composite filtration module, including a sludge thickening unit, a plate and frame filter press unit, and a drying unit arranged in sequence. The sludge thickening unit reduces the sludge moisture content to ≤95% by gravity settling in a sludge thickening tank. The plate and frame filter press unit uses a plate and frame filter press to press the settled sludge into sludge cakes using a high-pressure diaphragm, with a moisture content ≤60%. The drying unit uses the waste heat from the energy recovery module to perform low-temperature drying treatment on the sludge cakes, with a moisture content ≤30%.

7. An environmentally friendly filtration device for municipal drainage according to claim 1, characterized in that: The intelligent control module includes a PLC control unit, a multi-parameter sensing unit, a variable frequency water pump, an electric regulating valve, and a human-machine interaction unit. The PLC control unit is used for the overall coordinated control of the various modules of the device. The multi-parameter sensing unit collects data on influent flow rate, turbidity, pressure difference across the membrane in the multi-stage composite filtration module, and water temperature in real time through multi-parameter sensors, specifically including a flow sensor, a turbidity sensor, a pressure sensor, and a water temperature sensor. The variable frequency water pump dynamically adjusts the water pressure according to the influent flow rate. The electric regulating valve is used to adjust the flow rate, pressure, and direction of water and air in each pipeline. The human-machine interaction unit is used for visual interaction by the operator.

8. An environmentally friendly filtration device for municipal drainage according to claim 1, characterized in that: The energy recovery module includes a micro hydropower generation unit, a heat exchange unit, and an energy storage unit. The micro hydropower generation unit generates electricity using the potential energy of the overflow water from the multi-stage composite filtration module through a micro hydropower generator. The heat exchange unit transfers the heat energy from the temperature difference between the membrane filtration product water and the influent water of the multi-stage composite filtration module to the sludge treatment module based on a plate heat exchanger. The energy storage unit stores the electrical energy generated by the micro hydropower generation unit based on an energy storage battery, which is then used by the intelligent control module, sensors, and low-power devices.

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