A multi-stage solid-liquid separation vehicle-mounted septic tank intelligent pollution cleaning treatment system

Abstract

The application discloses a kind of multistage solid-liquid separation vehicle-mounted septic tank intelligent pollution cleaning treatment systems, relating to septic tank pollution cleaning treatment technical field, vacuum suction unit is extracted and stored after solid-liquid mixture in septic tank, in turn, large-particle solid impurities are intercepted by first rough separation module, fine separation module is separated by centrifugal sedimentation fine particle suspended solids, and standard discharge clean water is obtained by three-stage advanced treatment module through flocculation sedimentation and membrane filtration combined processing, and intelligent control unit can dynamically adjust each unit operating parameter to match different septic tank pollution characteristics.The application can realize septic tank pollution on-site treatment, avoid secondary pollution in the process of transfer, separation precision is high, and the water can be directly discharged or reused, self-adaptive regulation and control adapt to different pollution working conditions, and can be independently operated in the absence of mains electricity in the wild scene, stable operation, low maintenance cost, adapt to various septic tank pollution needs in urban and rural areas.

Description

Technical Field

[0001] This invention relates to the field of septic tank cleaning and treatment technology, and in particular to a multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system. Background Technology

[0002] Currently, septic tank cleaning generally employs traditional vacuum truck operations. During these operations, only the solid-liquid mixture of waste from the septic tank can be directly pumped, loaded, and transported to centralized treatment stations. This transportation process is prone to leaks and spills due to inadequate sealing, posing a risk of secondary pollution such as odor diffusion and waste spillage. Furthermore, the high water content of the mixed waste limits the effective waste loading capacity per trip, requiring multiple trips between the work site and the treatment station, resulting in low operational efficiency. Some unqualified operators also indiscriminately dump the pumped waste, polluting surrounding water bodies and soil, which violates relevant urban and rural environmental governance requirements.

[0003] Currently, some vehicle-mounted septic tank cleaning devices with simplified treatment functions have appeared on the market. Most of these devices only have a single-stage screen separation structure, which can only intercept solid impurities with a larger particle size. The separation accuracy is low, and the liquid phase after screening still contains a large amount of fine particulate matter and organic colloids, which cannot meet the requirements for direct discharge and still requires subsequent transportation and treatment. At the same time, the operating parameters of these devices are mostly fixed preset values, which cannot be adapted to the differences in the characteristics of sludge in different septic tanks. The solid phase concentration, particle composition, and pollutant concentration of sludge in septic tanks vary greatly in different areas and at different cleaning cycles. Under fixed parameters, problems such as incomplete separation and substandard effluent may occur, or the equipment may operate ineffectively and consume too much energy. Most of these devices also require external mains power, making it impossible to operate normally in old residential areas and rural areas without supporting power supply facilities, which significantly limits their applicable scenarios.

[0004] The existing vehicle-mounted wastewater treatment equipment also has several shortcomings in its supporting processes. The solid-liquid mixture is not homogenized before entering the separation unit, and large agglomerated waste can easily cause screen blockage, fluctuations in centrifugal separation load, and a high equipment failure rate. Flocculant addition mostly adopts a fixed flow rate mode, which cannot adjust the dosage according to fluctuations in influent water quality, and is prone to problems such as waste of reagents or insufficient flocculation effect. Ultrafiltration membrane modules mostly adopt a fixed cycle backwash mode, which cannot adjust the backwashing timing according to the actual membrane fouling situation. Either over-washing causes waste of water resources and energy, or untimely washing leads to excessively rapid decline in membrane flux. The equipment maintenance cycle is short, the operation and maintenance cost is high, and it is difficult to guarantee long-term stable treatment effect. Summary of the Invention

[0005] This invention proposes a multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system to solve the problems mentioned in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system, comprising: The vehicle chassis platform integrates a vacuum suction unit, a multi-stage solid-liquid separation unit, an intelligent control unit, and an energy supply unit, and is compatible with light truck chassis to enable rapid deployment at work sites. The vacuum suction unit includes a variable frequency vacuum pump set, a vacuum buffer tank and a retractable suction pipe connected in sequence. Under the command of the intelligent control unit, the variable frequency vacuum pump set generates negative pressure in the variable frequency speed regulation mode to suck the solid-liquid mixture in the septic tank to the vacuum buffer tank through the suction pipe. The primary coarse separation module has a built-in rotary screen solid-liquid separator to perform preliminary screening of the solid-liquid mixture output from the vacuum buffer tank to intercept large-particle solid impurities. The intercepted solid impurities are discharged into the solid residue collection bin via a screw conveyor mechanism. The secondary fine separation module receives the liquid mixture output from the primary coarse separation module, and uses a differential centrifuge to separate fine particulate suspensions by centrifugation and sedimentation based on the density difference between the solid and liquid phases, and discharges the separated concentrated sludge into the sludge temporary storage hopper. The three-stage deep treatment module receives the supernatant output from the two-stage fine separation module and sequentially passes it through a flocculation stirring reactor and a submerged ultrafiltration membrane module for combined flocculation sedimentation and membrane filtration treatment to obtain compliant discharge clean water. The intelligent control unit includes a multi-parameter sensor array deployed in each separation module, an embedded industrial controller, and an adaptive cleaning strategy module running on the embedded industrial controller. The multi-parameter sensor array collects liquid level, turbidity, flow rate, solid concentration, and pressure parameters in real time. The adaptive cleaning strategy module dynamically adjusts the speed of the variable frequency vacuum pump group, the speed of the differential centrifuge, and the amount of flocculant added based on the sensor fusion data to match the characteristics of septic tank sludge under different operating conditions.

[0007] Furthermore, it also includes a solid-liquid mixture pre-homogenization module, which is located between the vacuum buffer tank and the primary coarse separation module and has a built-in shear homogenizer. The shear homogenizer applies shear stirring to the solid-liquid mixture before it enters the primary coarse separation module to break up large agglomerates and uniformly disperse solid particles in the liquid phase. The rotational speed of the shear homogenizer is determined according to the following adaptive homogenization control law: In the formula This refers to the real-time rotational speed of the homogenizer. The reference speed for the homogenizer. This is the homogeneous strength adjustment coefficient. For the actual measurement of solid phase concentration by sensor array, This is the standard value for solid phase concentration.

[0008] Furthermore, it also includes an energy recovery and self-sustaining module, which includes a solar photovoltaic panel array, an energy storage battery pack, and an energy management circuit. The solar photovoltaic panel array is laid on the top of the vehicle chassis platform and charges the energy storage battery pack through the energy management circuit. In field operation scenarios without external mains power, the energy storage battery pack independently supplies power to the vacuum suction unit, the multi-stage solid-liquid separation unit, and the intelligent control unit. The energy management circuit monitors the state of charge of the energy storage battery pack in real time and automatically switches to the vehicle chassis engine power take-off mode when the state of charge is lower than a preset threshold to achieve uninterrupted continuous operation.

[0009] Furthermore, the rotary screen solid-liquid separator of the primary coarse separation module adopts a multi-stage variable aperture screen combination. The screens are arranged sequentially along the material flow direction, with the first screening section, the second screening section, and the third screening section. The aperture of the screens in each screening section decreases progressively, and the ratio of the aperture of adjacent screens satisfies the following gradation relationship: In the formula For the first The aperture size of the sieve in the screening section, For the first The aperture size of the sieve in the screening section, The pore size reduction factor is the particle size cut-off in the first screening stage. Large impurities, the particle size retained in the second screening stage is between to Medium impurities, the particle size cutoff in the third screening stage is between to Fine impurities and unretained liquid phase mixtures are separated and enter the secondary fine separation module through the outlet of the third screening section.

[0010] Furthermore, the differential centrifuge of the secondary fine separation module includes an inner rotating drum and an outer rotating drum coaxially mounted, with the inner rotating drum rotating at a first angular velocity. The rotation generates a primary centrifugal field that causes suspended particles larger than the critical particle size to settle outwards. The outer rotating cylinder rotates at a second angular velocity. The reverse rotation creates a differential shear flow field to peel off the organic colloidal layer attached to the surface of the particles. The inner and outer rotating cylinders rotate in opposite directions and the first angular velocity is greater than the second angular velocity. The bottom of the differential centrifuge is equipped with an adjustable sludge discharge gate valve. The opening degree of the adjustable sludge discharge gate valve is adjusted in a closed loop by the intelligent control unit based on the real-time feedback from the sludge level sensor in the sludge storage hopper.

[0011] Furthermore, the membrane flux in the submerged ultrafiltration membrane module of the three-stage deep treatment module is periodically adjusted via online backwashing according to the following membrane fouling control law: In the formula This refers to the real-time membrane flux of the ultrafiltration membrane. The initial membrane flux for cleaning the membrane, The membrane fouling attenuation coefficient is... This is the real-time measured value of the transmembrane pressure difference. For the total resistance of the filter cake layer on the membrane surface, when decay to When the preset ratio is below a certain threshold, the intelligent control unit triggers the backwash pump to perform pulsed backwashing on the ultrafiltration membrane module to restore membrane flux.

[0012] Furthermore, the adaptive cleaning strategy module of the intelligent control unit internally runs a multi-objective parameter coordination algorithm based on fuzzy inference. The multi-objective parameter coordination algorithm takes maximizing the overall efficiency of solid-liquid separation, minimizing the energy consumption per unit of treatment capacity, and achieving the standard of effluent turbidity as three optimization sub-objectives. It constructs a working condition feature vector by collecting liquid level, turbidity, flow rate, solid concentration, and pressure parameters in real time through a multi-parameter sensor array. A fuzzy inference rule base is established between the working condition feature vector and the optimization sub-objectives, and the speed adjustment command of the variable frequency vacuum pump group, the frequency adjustment command of the differential centrifuge, and the flow rate adjustment command of the flocculant dosing pump are dynamically output according to the membership degree of the real-time working condition feature vector.

[0013] Furthermore, a multi-stage solid-liquid separation vehicle-mounted septic tank intelligent cleaning and treatment method includes the following steps: Step 1: Once the vehicle chassis platform is in place, drive it to the target septic tank operation location and lock the parking brake. Extend the retractable suction pipe and lower the suction port to a preset depth below the septic tank liquid level. Step 2: Vacuum suction. The intelligent control unit sends a start command to the variable frequency vacuum pump set. After the variable frequency vacuum pump set establishes a vacuum by operating at an initial low frequency, it gradually increases the frequency to the target suction frequency based on the feedback from the pressure sensor in the vacuum buffer tank. The solid-liquid mixture in the septic tank is then suctioned into the vacuum buffer tank through the suction pipe and buffered. Step 3: Primary coarse separation. The solid-liquid mixture in the vacuum buffer tank enters the rotary screen solid-liquid separator under the combined action of gravity and vacuum residual pressure. The rotary screen solid-liquid separator rotates at a preset speed to screen and retain large-particle solid impurities. The retained solids are discharged into the solid residue collection bin through a screw conveyor mechanism. The liquid phase mixture flows out from the screen outlet and enters the secondary fine separation module. Step 4: Secondary fine separation. After the liquid mixture enters the differential centrifuge, the inner and outer rotating drums rotate in opposite directions at different speeds, creating a combined force field environment of centrifugal sedimentation field and shear stripping field. Under the action of the combined force field, fine particulate suspended matter settles to the cylinder wall to form a concentrated sludge layer, which is discharged into the sludge temporary storage hopper through the adjustable sludge discharge gate valve. The supernatant is discharged from the overflow port at the top of the differential centrifuge and enters the tertiary deep treatment module. Step 5: The supernatant enters the flocculation stirring reactor and is mixed with the flocculant dosage commanded by the intelligent control unit to generate flocs. The mixture containing flocs enters the submerged ultrafiltration membrane module and, driven by the transmembrane pressure difference, separates the flocs from the water through membrane separation. The water is discharged through the effluent pipe in compliance with standards or recycled. Step Six: Intelligent Closed-Loop Control. Throughout the entire process from Step Two to Step Five, the intelligent control unit continuously collects the operating parameters of each separation module through a multi-parameter sensor array and runs the adaptive cleaning strategy module to perform online rolling optimization and adjustment of the control quantities of each actuator to adapt to the real-time changes in the characteristics of sludge in the septic tank.

[0014] Furthermore, in step five, the determination of the flocculant dosage adopts a feedforward and feedback composite control strategy based on influent turbidity and flow rate. The feedforward part calculates the basic dosage based on influent turbidity and flow rate, while the feedback part makes real-time corrections based on the effluent turbidity deviation. The real-time flow command of the flocculant dosing pump is determined by the following formula: In the formula This is the real-time flow command for the flocculant dosing pump. This is the feedforward addition coefficient. This refers to the real-time flow rate of the supernatant entering the flocculation stirred reactor. The real-time turbidity of the supernatant entering the flocculation stirred reactor. To ensure that the turbidity of the effluent meets the discharge standard value, For feedback correction coefficient, For the turbidity of the effluent at time Real-time detection values, This refers to the current moment.

[0015] Furthermore, in step four, the first angular velocity of the inner rotating drum of the differential centrifugal separator... With the second angular velocity of the outer rotating cylinder The intelligent control unit performs coordinated adaptive adjustment based on the solid concentration and flow rate of the liquid mixture entering the differential centrifuge. When the solid concentration of the liquid mixture increases, the absolute difference between the first angular velocity of the inner drum and the second angular velocity of the outer drum is increased simultaneously to enhance the centrifugal sedimentation driving force. When the solid concentration of the liquid mixture decreases, the absolute difference between the first angular velocity of the inner drum and the second angular velocity of the outer drum is decreased simultaneously.

[0016] Compared with existing technologies, the beneficial effects of this invention are: This invention utilizes a vehicle-mounted integrated multi-stage solid-liquid separation structure and adaptive control scheme to achieve on-site treatment of septic tank waste, eliminating the need to transport mixed waste to centralized treatment stations and avoiding secondary pollution problems during transportation. The flexible deployment adapts to various operational scenarios. The three-stage solid-liquid separation process combines coarse screening to remove large-particle impurities, differential centrifugation to separate fine suspended solids, and deep treatment through a combination of flocculation and ultrafiltration. Each treatment unit is interconnected and matched, allowing solid impurities and pollutants in the waste to be gradually separated and removed. The final clean water meets discharge requirements and can also be directly recycled for use in municipal greening, road washing, and other applications.

[0017] The pre-homogenization module homogenizes the solid-liquid mixture before it enters the separation unit, breaking up large agglomerates of contaminants and ensuring uniform dispersion of solid particles in the liquid phase. This reduces the probability of subsequent screen clogging and improves the operational stability of subsequent centrifugal separation and advanced treatment. The differential centrifuge employs a reverse differential dual-rotor structure, generating a centrifugal settling field while simultaneously creating a shear flow field. This strips away organic colloids adhering to the surface of suspended particles, enhancing the separation of fine particles and reducing the contaminant load on subsequent advanced treatment units.

[0018] The intelligent control unit's adaptive control logic dynamically adjusts the operating parameters of each actuator based on real-time operating parameters collected by various sensors. This adapts to the different characteristics of sludge in various septic tanks, eliminating the need for manual parameter adjustments based on operator experience. This ensures operational stability under different working conditions and allows for power adjustments based on actual load, preventing unnecessary energy consumption. The energy recovery and self-sustaining module enables power generation from solar energy storage or a vehicle-mounted engine in scenarios without external mains power, expanding the equipment's applicability and ensuring continuous operation. The flocculant dosing system employs a feedforward and feedback composite control logic, adjusting the dosage according to the influent water quality and flow rate. This avoids both waste and secondary pollution from overdosing and poor flocculation due to underdosing. The ultrafiltration membrane backwashing logic is triggered by actual membrane fouling, promptly restoring membrane flux, extending membrane module lifespan, and reducing equipment maintenance frequency. The entire septic tank cleaning and treatment method adopts a closed-loop control throughout the process, with the operating parameters of each treatment link matched to each other, which can ensure the stable operation of the entire treatment process. It has low professional requirements for operators and is suitable for the septic tank cleaning and treatment needs of different urban and rural areas. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating the overall operation of the multi-stage solid-liquid separation vehicle-mounted septic tank intelligent cleaning and treatment system proposed in this invention. Figure 2 This is a flowchart of the vacuum suction and solid-liquid mixture pre-homogenization process of the present invention; Figure 3 This is a flowchart of the multi-stage physical sieving and differential centrifugation process of the present invention; Figure 4 This is a flowchart of the three-stage deep treatment and ultrafiltration membrane adaptive backwashing process of the present invention; Figure 5 This is a flowchart illustrating the intelligent adaptive control and energy management switching process of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Reference Figures 1 to 5 This invention discloses a multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system, comprising: The vehicle chassis platform integrates a vacuum suction unit, a multi-stage solid-liquid separation unit, an intelligent control unit, and an energy supply unit, and is compatible with light truck chassis to enable rapid deployment at work sites. The vacuum suction unit includes a variable frequency vacuum pump set, a vacuum buffer tank and a retractable suction pipe connected in sequence. Under the command of the intelligent control unit, the variable frequency vacuum pump set generates negative pressure in the variable frequency speed regulation mode to suck the solid-liquid mixture in the septic tank to the vacuum buffer tank through the suction pipe. The primary coarse separation module has a built-in rotary screen solid-liquid separator to perform preliminary screening of the solid-liquid mixture output from the vacuum buffer tank to intercept large-particle solid impurities. The intercepted solid impurities are discharged into the solid residue collection bin via a screw conveyor mechanism. The secondary fine separation module receives the liquid mixture output from the primary coarse separation module, and uses a differential centrifuge to separate fine particulate suspensions by centrifugation and sedimentation based on the density difference between the solid and liquid phases, and discharges the separated concentrated sludge into the sludge temporary storage hopper. The three-stage deep treatment module receives the supernatant output from the two-stage fine separation module and sequentially passes it through a flocculation stirring reactor and a submerged ultrafiltration membrane module for combined flocculation sedimentation and membrane filtration treatment to obtain compliant discharge clean water. The intelligent control unit includes a multi-parameter sensor array deployed in each separation module, an embedded industrial controller, and an adaptive cleaning strategy module running on the embedded industrial controller. The multi-parameter sensor array collects liquid level, turbidity, flow rate, solid concentration, and pressure parameters in real time. The adaptive cleaning strategy module dynamically adjusts the speed of the variable frequency vacuum pump group, the speed of the differential centrifuge, and the amount of flocculant added based on the sensor fusion data to match the characteristics of septic tank sludge under different operating conditions.

[0022] This invention also includes a solid-liquid mixture pre-homogenization module, which is located between the vacuum buffer tank and the primary coarse separation module and incorporates a shear homogenizer. The shear homogenizer applies shear stirring to the solid-liquid mixture before it enters the primary coarse separation module to break up large agglomerates and uniformly disperse solid particles in the liquid phase. The rotational speed of the shear homogenizer is determined according to the following adaptive homogenization control law: In the formula The real-time rotational speed of the homogenizer is expressed in revolutions per minute (r / min). The reference rotational speed of the homogenizer is expressed in revolutions per minute (r / min). This is a homogeneous intensity adjustment coefficient, dimensionless, with a value ranging from 0.2 to 0.8. The solid concentration measured by the sensor array is expressed in grams per liter (g / L). This is a standard value for solid phase concentration, expressed in grams per liter (g / L).

[0023] This invention also includes an energy recovery and self-sustaining module, which comprises a solar photovoltaic panel array, an energy storage battery pack, and an energy management circuit. The solar photovoltaic panel array is laid on the top of the vehicle chassis platform and charges the energy storage battery pack through the energy management circuit. In field operation scenarios without external mains power, the energy storage battery pack independently supplies power to the vacuum suction unit, the multi-stage solid-liquid separation unit, and the intelligent control unit. The energy management circuit monitors the state of charge of the energy storage battery pack in real time and automatically switches to the vehicle chassis engine power take-off mode when the state of charge is lower than a preset threshold to achieve uninterrupted continuous operation.

[0024] In this invention, the rotary screen solid-liquid separator of the primary coarse separation module adopts a multi-stage variable aperture screen combination. The screens are arranged sequentially along the material flow direction, with the first screening section, the second screening section, and the third screening section. The aperture of the screens in each screening section decreases progressively, and the ratio of the aperture of adjacent screens satisfies the following gradation relationship: In the formula For the first The aperture diameter of the sieve in the screening section is expressed in millimeters (mm). For the first The aperture diameter of the sieve in the screening section is expressed in millimeters (mm). is the pore size reduction factor, dimensionless, ranging from 1.3 to 2.0, where the first screening stage retains particles larger than 1.3. Large impurities, the particle size retained in the second screening stage is between to Medium impurities, the particle size cutoff in the third screening stage is between to Fine impurities and unretained liquid phase mixtures are separated and enter the secondary fine separation module through the outlet of the third screening section.

[0025] In this invention, the differential centrifuge of the secondary fine separation module includes an inner rotating drum and an outer rotating drum coaxially mounted, the inner rotating drum rotating at a first angular velocity. The rotation generates a primary centrifugal field that causes suspended particles larger than the critical particle size to settle outwards. The outer rotating cylinder rotates at a second angular velocity. The reverse rotation creates a differential shear flow field to peel off the organic colloidal layer attached to the particle surface. The inner and outer rotating cylinders rotate in opposite directions, and the first angular velocity is greater than the second angular velocity. The bottom of the differential centrifuge is equipped with an adjustable sludge discharge gate valve. The opening of the adjustable sludge discharge gate valve is adjusted in a closed loop by the intelligent control unit based on the real-time feedback from the sludge level sensor in the sludge storage hopper to prevent excessive sludge accumulation from causing a decrease in centrifugal separation efficiency.

[0026] In this invention, the membrane flux in the submerged ultrafiltration membrane module of the three-stage deep treatment module is periodically adjusted via online backwashing according to the following membrane fouling control law: In the formula This refers to the real-time membrane flux of the ultrafiltration membrane, expressed in liters per square meter per hour. ), Initial membrane flux for cleaning membrane, expressed in liters per square meter per hour (L / h). ), The membrane fouling attenuation coefficient is determined by the properties of the membrane material and is expressed in bar per meter (m). ), This is the real-time measured value of the transmembrane pressure difference, in bar. The total resistance of the filter cake layer on the membrane surface is calculated from the filter cake layer thickness and specific resistance parameters using Darcy's law, and the unit is per meter ( ),when decay to When the preset ratio is below a certain threshold, the intelligent control unit triggers the backwash pump to perform pulsed backwashing on the ultrafiltration membrane module to restore membrane flux.

[0027] In this invention, the adaptive cleaning strategy module of the intelligent control unit internally runs a multi-objective parameter coordination algorithm based on fuzzy inference. The multi-objective parameter coordination algorithm takes maximizing the overall efficiency of solid-liquid separation, minimizing the energy consumption per unit processing volume, and achieving the standard turbidity of the effluent as three optimization sub-objectives. It constructs a working condition feature vector by collecting liquid level, turbidity, flow rate, solid concentration, and pressure parameters in real time through a multi-parameter sensor array. A fuzzy inference rule base is established between the working condition feature vector and the optimization sub-objectives. Based on the membership degree of the real-time working condition feature vector, it dynamically outputs speed adjustment commands for the variable frequency vacuum pump group, frequency adjustment commands for the differential centrifuge, and flow rate adjustment commands for the flocculant dosing pump. This ensures that the cleaning process always operates at the comprehensive optimal working point under different septic tank sludge characteristics in different operating scenarios.

[0028] This invention discloses a multi-stage solid-liquid separation vehicle-mounted septic tank intelligent cleaning and treatment method, comprising the following steps: Step 1: Once the vehicle chassis platform is in place, drive it to the target septic tank operation location and lock the parking brake. Extend the retractable suction pipe and lower the suction port to a preset depth below the septic tank liquid level. Step 2: Vacuum suction. The intelligent control unit sends a start command to the variable frequency vacuum pump set. After the variable frequency vacuum pump set establishes a vacuum by operating at an initial low frequency, it gradually increases the frequency to the target suction frequency based on the feedback from the pressure sensor in the vacuum buffer tank. The solid-liquid mixture in the septic tank is then suctioned into the vacuum buffer tank through the suction pipe and buffered. Step 3: Primary coarse separation. The solid-liquid mixture in the vacuum buffer tank enters the rotary screen solid-liquid separator under the combined action of gravity and vacuum residual pressure. The rotary screen solid-liquid separator rotates at a preset speed to screen and retain large-particle solid impurities. The retained solids are discharged into the solid residue collection bin through a screw conveyor mechanism. The liquid phase mixture flows out from the screen outlet and enters the secondary fine separation module. Step 4: Secondary fine separation. After the liquid mixture enters the differential centrifuge, the inner and outer rotating drums rotate in opposite directions at different speeds, creating a combined force field environment of centrifugal sedimentation field and shear stripping field. Under the action of the combined force field, fine particulate suspended matter settles to the cylinder wall to form a concentrated sludge layer, which is discharged into the sludge temporary storage hopper through the adjustable sludge discharge gate valve. The supernatant is discharged from the overflow port at the top of the differential centrifuge and enters the tertiary deep treatment module. Step 5: The supernatant enters the flocculation stirring reactor and is mixed with the flocculant dosage commanded by the intelligent control unit to generate flocs. The mixture containing flocs enters the submerged ultrafiltration membrane module and, driven by the transmembrane pressure difference, separates the flocs from the water through membrane separation. The water is discharged through the effluent pipe in compliance with standards or recycled. Step Six: Intelligent Closed-Loop Control. Throughout the entire process from Step Two to Step Five, the intelligent control unit continuously collects the operating parameters of each separation module through a multi-parameter sensor array and runs the adaptive cleaning strategy module to perform online rolling optimization and adjustment of the control quantities of each actuator to adapt to the real-time changes in the characteristics of sludge in the septic tank.

[0029] In this invention, the determination of the flocculant dosage in step five adopts a feedforward and feedback composite control strategy based on influent turbidity and flow rate. The feedforward part calculates the basic dosage based on influent turbidity and flow rate, and the feedback part makes real-time corrections based on the effluent turbidity deviation. The real-time flow command of the flocculant dosing pump is determined by the following formula: In the formula This is the real-time flow command for the flocculant dosing pump, expressed in liters per hour (L / h). This is the feedforward dosing coefficient, dimensionless, determined by beaker tests based on the type of flocculant and wastewater. The real-time flow rate of the supernatant entering the flocculation stirred reactor is expressed in liters per hour (L / h). The real-time turbidity of the supernatant entering the flocculation stirred reactor is expressed in NTU. The turbidity of the effluent meets the discharge standard value, and the unit is NTU. For feedback correction factor, the unit is liters per (NTU·hour²) ), For the turbidity of the effluent at time Real-time detection values, in NTU. The current time is expressed in hours (h). The integral term accumulates the turbidity deviation of the effluent to achieve zero static error adjustment.

[0030] In this invention, the first angular velocity of the inner rotating drum of the differential centrifugal separator in step four... With the second angular velocity of the outer rotating cylinder The intelligent control unit performs coordinated adaptive adjustment based on the solid concentration and flow rate of the liquid mixture entering the differential centrifuge. When the solid concentration of the liquid mixture increases, the absolute difference between the first angular velocity of the inner drum and the second angular velocity of the outer drum is increased simultaneously to enhance the centrifugal sedimentation driving force. When the solid concentration of the liquid mixture decreases, the absolute difference between the first angular velocity of the inner drum and the second angular velocity of the outer drum is decreased simultaneously to reduce energy consumption. The ratio of the angular velocities of the inner and outer drums remains constant, so that the flow pattern of the differential shear flow field remains basically unchanged, ensuring that the centrifugal sedimentation separation efficiency of fine particulate suspension remains stable under different solid concentration conditions.

[0031] The following two examples will provide further explanation: Example 1 This embodiment is applied to septic tank cleaning operations in old residential areas of urban built-up areas. The work area has access to external mains power. The septic tank to be cleaned is scheduled for an 18-month cleaning cycle, and the concentration of solid waste is in a moderate range. After the vehicle-mounted chassis platform, adapted to a light truck chassis, travels to the designated work position around the target septic tank, the parking brake is locked, and the operator extends the retractable suction pipe, lowering the suction port to 1.2 meters below the septic tank surface, avoiding the scum layer on the surface and the thick layer of solid sludge deposited at the bottom.

[0032] After the intelligent control unit completes its power-on self-test, it sends a start command to the variable frequency vacuum pump unit. The variable frequency vacuum pump unit operates at an initial low frequency. Once the negative pressure in the vacuum buffer tank reaches the preset initial value, the operating frequency is gradually increased based on real-time feedback from the pressure sensor inside the vacuum buffer tank. This continuously draws the solid-liquid mixture from the septic tank into the vacuum buffer tank via the suction pipe. Under the combined action of gravity and residual pressure inside the tank, the solid-liquid mixture enters the solid-liquid mixture pre-homogenization module located between the buffer tank and the primary coarse separation module. The module's built-in shear homogenizer applies continuous shearing and stirring to the input solid-liquid mixture, breaking down large pieces of fabric and agglomerated organic waste, thus uniformly dispersing solid particles in the liquid phase. The homogenizer's rotation speed is dynamically adjusted by the intelligent control unit based on real-time collected solid concentration parameters to adapt to the current waste concentration characteristics.

[0033] The homogenized solid-liquid mixture enters the rotary screen solid-liquid separator of the primary coarse separation module. In this embodiment, the rotary screen adopts a three-stage variable aperture combination structure, with the first screening section, the second screening section, and the third screening section set sequentially along the material flow direction. The aperture reduction coefficients of adjacent screening sections are 1.8 and 1.5, respectively, both within the set value range. The first screening section retains larger particles such as stones, fabrics, and plastic impurities. The second screening section retains medium-sized organic agglomerates. The third screening section retains smaller fine solid impurities. The solid impurities retained by each screening section are uniformly discharged into the solid slag collection bin for temporary storage via a screw conveyor mechanism. The liquid phase mixture that is not retained flows into the secondary fine separation module through the outlet of the third screening section.

[0034] After the liquid mixture enters the differential centrifuge in the secondary fine separation module, the coaxially mounted inner and outer drums rotate in opposite directions at a differential speed. The angular velocity of the inner drum is always greater than that of the outer drum, and the ratio of their angular velocities remains constant. The centrifugal field generated by the rotation of the inner drum drives the fine suspended particles to settle towards the drum wall, while the shear flow field generated by the counter-rotating outer drum strips away the organic colloidal layer attached to the surface of the suspended particles, improving the separation effect of fine particles. The operating speed of the differential centrifuge is dynamically adjusted by the intelligent control unit according to the solid concentration and flow rate of the input liquid phase. When the solid concentration increases, the angular velocity difference between the inner and outer drums is increased synchronously to enhance the centrifugal sedimentation driving force; when the solid concentration decreases, the angular velocity difference is decreased synchronously to reduce the energy consumption of the equipment. The concentrated sludge produced by the separation is discharged into the sludge storage hopper through an adjustable sludge discharge gate valve at the bottom. The opening of the gate valve is regulated in a closed loop by the intelligent control unit in conjunction with the sludge level sensor in the sludge storage hopper to prevent sludge accumulation from affecting the separation efficiency. The supernatant produced by the separation is discharged from the overflow port at the top of the differential centrifuge and enters the three-stage deep processing module.

[0035] The supernatant first enters the flocculation stirred reactor. The dosage of flocculant is determined by the intelligent control unit using a combined feedforward and feedback control logic. The feedforward part calculates the basic dosage based on the influent flow rate and turbidity, while the feedback part dynamically corrects the dosage based on the real-time deviation of the effluent turbidity, ensuring the dosage is adapted to the current pollutant load of the influent. After the supernatant and flocculant are thoroughly mixed and stirred, a flocculation reaction occurs, generating large flocs. The mixture containing the flocs then enters the submerged ultrafiltration membrane module, where the membrane separation process is completed under the drive of the transmembrane pressure difference. The flocs are retained in the reactor by the membrane, while the clean water permeates through the membrane layer and is collected through the effluent pipe. It can be directly discharged in compliance with standards or temporarily stored for use in scenarios such as watering community green spaces and washing roads. The intelligent control unit collects the transmembrane pressure difference and membrane flux parameters of the ultrafiltration membrane module in real time. When the membrane flux decays to a set ratio of the initial flux of the clean membrane, the backwash pump is automatically triggered to perform pulse backwashing on the ultrafiltration membrane module to restore the membrane flux.

[0036] In this embodiment, the adaptive cleaning strategy module of the intelligent control unit runs a multi-objective parameter coordination algorithm based on fuzzy inference. The algorithm's operating condition feature vector consists of five parameters collected in real time by a multi-parameter sensor array: liquid level, turbidity, flow rate, solid concentration, and pressure. Each parameter corresponds to three membership intervals: low, medium, and high. The optimization sub-objectives are set as maximizing the overall efficiency of solid-liquid separation, minimizing energy consumption per unit processing volume, and achieving the required effluent turbidity. A pre-built fuzzy inference rule base covers all combinations of typical operating condition features. The intelligent control unit matches the corresponding rules according to the membership degree of the real-time operating condition feature vector and dynamically outputs control commands to adjust the speed of the variable frequency vacuum pump group, the speed of the differential centrifuge separator, and the flow rate of the flocculant dosing pump, ensuring that the treatment process always adapts to the current characteristics of the pollutants. During operation, the energy supply unit prioritizes connecting to the external mains power to power all electrical modules. The solar photovoltaic panel array installed on the top of the vehicle chassis platform operates synchronously, charging the energy storage battery pack through the energy management circuit. The energy storage battery pack is in a float charging state and only serves as a backup power source when there is a temporary interruption in the external mains power.

[0037] This embodiment achieves on-site treatment of solid and liquid waste throughout the entire septic tank cleaning process, eliminating the need to transport large quantities of mixed waste with high water content and avoiding spillage and odor spread during transportation. The three-stage gradient separation process is adapted to the characteristics of waste in septic tanks of old urban residential areas. The operating parameters of each treatment unit are adaptively adjusted for higher matching, resulting in consistently compliant treated effluent. The pre-homogenization module reduces the probability of screen clogging, the differential centrifuge's dual-drum structure improves the removal of fine particulate impurities, and the composite control logic for flocculant dosing avoids waste. The entire system operates with high stability and minimal impact on the lives of surrounding residents.

[0038] Example 2 This embodiment is applied to septic tank cleaning operations in remote rural areas with contiguous residential areas. The work area has no external power supply, the septic tanks to be cleaned are scheduled for 36 months, the solid phase concentration of the sludge is in a high range, and it contains more agricultural waste and coarse fiber impurities. After the vehicle-mounted chassis platform, which is adapted to a light truck chassis, is driven to a level work position around the target septic tank, the parking brake is locked, and the operator extends the retractable suction pipe, lowering the suction port to 1.5 meters below the liquid surface of the septic tank, avoiding the surface layer of straw, fallen leaves, and other scum.

[0039] After the intelligent control unit completes its power-on self-test, it first activates the energy management circuit of the energy recovery and self-sustaining module to detect the state of charge of the energy storage battery pack. In this embodiment, the initial state of charge of the energy storage battery pack meets the startup requirements, and the energy management circuit switches to battery power supply mode to supply power to all power-consuming modules. The intelligent control unit then sends a start command to the variable frequency vacuum pump set. The variable frequency vacuum pump set operates at an initial low frequency. After the negative pressure in the vacuum buffer tank reaches the preset initial value, the operating frequency is gradually increased based on the real-time feedback from the pressure sensor in the vacuum buffer tank, continuously pumping the high-concentration solid-liquid mixture in the septic tank into the vacuum buffer tank for buffering through the suction pipe. Under the combined action of gravity and residual pressure inside the vacuum buffer tank, the solid-liquid mixture enters the solid-liquid mixture pre-homogenization module located between the buffer tank and the primary coarse separation module. The shear homogenizer built into the module applies high-speed shearing and stirring to the input solid-liquid mixture, breaking down impurities such as coarse fibers, large clumps of poultry and livestock manure, and detached biogas digester residue, so that the solid particles are evenly dispersed in the liquid phase. The rotation speed of the homogenizer is dynamically adjusted by the intelligent control unit according to the real-time collected solid phase concentration parameters to adapt to the characteristics of the current high concentration of waste.

[0040] The homogenized solid-liquid mixture enters the rotary screen solid-liquid separator of the primary coarse separation module. In this embodiment, the rotary screen adopts a three-stage variable aperture combination structure, with the first screening section, the second screening section, and the third screening section set sequentially along the material flow direction. The aperture reduction coefficients of adjacent screening sections are 1.6 and 1.4, respectively, both within the set value range. The first screening section intercepts impurities with larger particle sizes, such as straw, stones, and plastic packaging materials. The second screening section intercepts coarse fibers and organic agglomerates with medium particle sizes. The third screening section intercepts fine solid impurities with smaller particle sizes. The solid impurities intercepted by each screening section are uniformly discharged into the solid residue collection bin for temporary storage via a screw conveyor mechanism. The liquid phase mixture that is not intercepted flows into the secondary fine separation module through the outlet of the third screening section.

[0041] After the liquid mixture enters the differential centrifuge in the secondary fine separation module, the coaxially mounted inner and outer drums rotate in opposite directions at a differential speed. The angular velocity of the inner drum is always greater than that of the outer drum, and the ratio of their angular velocities remains constant. The high-intensity centrifugal field generated by the rotation of the inner drum drives the high-concentration fine particulate suspension to settle rapidly against the drum wall. The shear flow field generated by the counter-rotating outer drum strips away the humic colloidal layer attached to the surface of the suspended particles, improving the separation effect of fine particles. The operating speed of the differential centrifuge is dynamically adjusted by the intelligent control unit based on the high solids concentration and flow rate of the input liquid phase. Compared with urban operation scenarios, the angular velocity difference between the inner and outer drums is appropriately increased to enhance the centrifugal sedimentation driving force. When the solids concentration fluctuates, the angular velocity difference is adjusted synchronously to match the current processing load. The high-concentration concentrated sludge produced by the separation is discharged into the sludge temporary storage hopper through an adjustable sludge discharge gate valve at the bottom. The opening of the gate valve is regulated in a closed loop by the intelligent control unit in conjunction with the sludge level sensor in the sludge temporary storage hopper to prevent the accumulation of high-concentration sludge from clogging the sludge discharge channel. The supernatant produced by the separation is discharged from the overflow port at the top of the differential centrifuge and enters the three-stage deep processing module.

[0042] The supernatant first enters the flocculation stirred reactor. The dosage of flocculant is determined by the intelligent control unit using a combined feedforward and feedback control logic. The feedforward part calculates the basic dosage based on the high flow rate and high turbidity of the influent, while the feedback part dynamically corrects the dosage based on the real-time deviation of the effluent turbidity, ensuring that the dosage is adapted to the current high pollutant load of the influent. After the supernatant and flocculant are thoroughly mixed and stirred, a flocculation reaction occurs, generating large, dense flocs. The mixture containing the flocs then enters the submerged ultrafiltration membrane module, where the membrane separation process is completed under the drive of the transmembrane pressure difference. The flocs are retained in the reactor by the membrane, while the purified water permeates through the membrane layer and is collected through the effluent pipe. It can be directly discharged into the surrounding irrigation canals in compliance with standards, or temporarily stored for use in farmland irrigation, garden spraying, and other scenarios. The intelligent control unit collects the transmembrane pressure difference and membrane flux parameters of the ultrafiltration membrane module in real time. When the membrane flux decays to a set ratio of the initial flux of the clean membrane, the backwash pump is automatically triggered to perform pulse backwashing on the ultrafiltration membrane module to restore the membrane flux. Because the concentration of pollutants in the influent is higher in this embodiment, the frequency of backwashing is increased compared to urban operation scenarios.

[0043] In this embodiment, the adaptive cleaning strategy module of the intelligent control unit runs a multi-objective parameter coordination algorithm based on fuzzy inference. The algorithm's operating condition feature vector consists of five parameters collected in real time by a multi-parameter sensor array: liquid level, turbidity, flow rate, solid concentration, and pressure. Each parameter corresponds to three membership intervals: low, medium, and high. The optimization sub-objectives are set as maximizing the overall efficiency of solid-liquid separation, minimizing energy consumption per unit of treatment capacity, and achieving the standard for effluent turbidity. The pre-built fuzzy inference rule library covers typical operating condition feature combinations of high-concentration pollutants in rural areas. The intelligent control unit matches the corresponding rules according to the membership degree of the real-time operating condition feature vector and dynamically outputs control commands to adjust the speed of the variable frequency vacuum pump group, the speed of the differential centrifuge separator, and the flow rate of the flocculant dosing pump, so that the treatment process always adapts to the current characteristics of high-concentration pollutants. During the operation, the solar photovoltaic array installed on the top of the vehicle chassis platform runs continuously, charging the energy storage battery pack through the energy management circuit to replenish the power consumption during the operation. When the state of charge of the energy storage battery pack is lower than the preset threshold, the energy management circuit automatically switches to the vehicle chassis engine power take-off mode to ensure that the operation is uninterrupted and the entire cleaning operation can be completed without external power supply facilities.

[0044] The cleaning operation in this embodiment can be carried out independently in rural settings without external power supply. It can complete the entire process without the need for supporting power supply facilities, avoiding the secondary pollution risks associated with long-distance transport of waste in traditional operation modes. The three-stage gradient separation process is adapted to the high-concentration waste characteristics of rural septic tanks. The adaptive control logic can dynamically adjust operating parameters according to fluctuations in waste concentration. The treated effluent meets the water quality requirements for agricultural irrigation. The energy recovery and self-sustaining modules reduce fuel consumption during operation. The entire system is flexible in deployment, highly stable in operation, and suitable for the cleaning needs of decentralized septic tanks in rural areas.

[0045] Reference Figure 1 This flowchart illustrates the macroscopic operational steps and material flow of the intelligent cleaning and treatment method for vehicle-mounted septic tanks. During operation, the integrated vehicle-mounted chassis platform is first deployed to the target location. Then, under the command of the intelligent control unit, the variable frequency vacuum pump unit establishes negative pressure, smoothly drawing the solid-liquid mixture from the septic tank into the system. Next, the material sequentially enters the primary coarse separation module for preliminary screening and retention of solid impurities of different particle sizes. It then enters the secondary fine separation module, where composite centrifugation technology achieves sedimentation and dewatering of fine suspended particles. Finally, the supernatant is introduced into the tertiary deep treatment module, where flocculation and ultrafiltration membrane filtration produce standard-compliant clean water for discharge. The resulting solid residue and concentrated sludge are collected and temporarily stored, achieving environmentally friendly treatment throughout the entire process.

[0046] Reference Figure 2This flowchart details the vacuum suction and pre-homogenization process of septic tank waste. After startup, the control unit instructs the variable frequency vacuum pump unit to establish a stable vacuum environment by gradually increasing the frequency, drawing the solid-liquid mixture from the septic tank into a vacuum buffer tank via a retractable pipeline. To prevent clogging of subsequent precision equipment, the material must pass through a pre-homogenization module before entering the screening module. This module has a built-in shear homogenizer; the system dynamically adjusts its stirring speed based on the measured solid concentration, applying strong shearing force to the mixture. This process effectively breaks down large agglomerates commonly found in septic tank waste, promoting uniform dispersion of solid components in the liquid phase, laying a solid foundation for subsequent multi-stage solid-liquid separation.

[0047] Reference Figure 3 This flow chart illustrates the core mechanical dewatering logic of primary coarse separation and secondary fine separation. The mixed liquor first enters a rotary screen solid-liquid separator equipped with a multi-stage variable pore size structure, passing sequentially through the first to third screening stages along the flow direction, filtering from coarse to fine impurities in stages. The retained material is discharged into the collection bin by a screw conveyor mechanism. The liquid phase after coarse screening is then pumped into a differential centrifuge. Inside the equipment, the inner and outer rotating cylinders rotate in opposite directions with intelligently matched angular velocities, creating a composite physical field combining sedimentation and shear stripping. Fine suspended particles rapidly settle to the cylinder wall under this force field, forming sludge, which is discharged through a closed-loop controlled sludge discharge valve. The purified supernatant then smoothly overflows into the next advanced treatment stage.

[0048] Reference Figure 4 This flowchart illustrates the water purification and ultrafiltration membrane maintenance control mechanism of the three-stage advanced treatment module. The supernatant after centrifugation enters the flocculation reactor. The system employs a combined feedforward and feedback control strategy, determining the basic reagent dosage based on the instantaneous turbidity and flow rate of the influent, and adjusting the pump flow rate in real time according to the final effluent turbidity deviation to ensure sufficient flocculation of pollutants. The mixture then enters the submerged ultrafiltration membrane module, where it traps small particles and large organic molecules under pressure differential. To maintain efficient operation, the system continuously monitors the transmembrane pressure differential and membrane flux parameters. Once the filter cake layer resistance causes flux decline beyond the safety limit, a pulsed backwashing procedure is immediately triggered to restore the filtration performance of the membrane module online.

[0049] Reference Figure 5This flowchart illustrates the intelligent parameter coordination and self-sustaining energy management logic of the cleaning system. At the information decision-making level, a multi-parameter sensor array continuously captures state characteristics such as liquid level, turbidity, and solids content. The adaptive strategy module then executes a multi-objective coordination algorithm based on this data, balancing separation efficiency and overall energy consumption while ensuring effluent quality, and dynamically issuing optimal operating instructions to each core actuator. At the energy security level, the system fully utilizes photovoltaic panels installed on the vehicle's roof to collect solar energy and store it in the battery pack. The energy management circuit constantly monitors the battery pack's charge level. In situations where there is no mains power and the battery is low, it can seamlessly switch to the vehicle's chassis engine power take-off mode, completely eliminating range anxiety and ensuring the continuity of cleaning operations.

[0050] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system, characterized in that, include: The vehicle chassis platform integrates a vacuum suction unit, a multi-stage solid-liquid separation unit, an intelligent control unit, and an energy supply unit, and is compatible with light truck chassis to enable rapid deployment at work sites. The vacuum suction unit includes a variable frequency vacuum pump set, a vacuum buffer tank and a retractable suction pipe connected in sequence. Under the command of the intelligent control unit, the variable frequency vacuum pump set generates negative pressure in the variable frequency speed regulation mode to suck the solid-liquid mixture in the septic tank to the vacuum buffer tank through the suction pipe. The primary coarse separation module has a built-in rotary screen solid-liquid separator to perform preliminary screening of the solid-liquid mixture output from the vacuum buffer tank to intercept large-particle solid impurities. The intercepted solid impurities are discharged into the solid residue collection bin via a screw conveyor mechanism. The secondary fine separation module receives the liquid mixture output from the primary coarse separation module, and uses a differential centrifuge to separate the fine particulate suspension by centrifugation and sedimentation based on the density difference between the solid and liquid phases, and discharges the separated concentrated sludge into the sludge temporary storage hopper. The three-stage deep treatment module receives the supernatant output from the two-stage fine separation module and sequentially passes it through a flocculation stirring reactor and a submerged ultrafiltration membrane module for combined flocculation sedimentation and membrane filtration treatment to obtain compliant discharge clean water. The intelligent control unit includes a multi-parameter sensor array deployed in each separation module, an embedded industrial controller, and an adaptive cleaning strategy module running on the embedded industrial controller. The multi-parameter sensor array collects liquid level, turbidity, flow rate, solid concentration, and pressure parameters in real time. The adaptive cleaning strategy module dynamically adjusts the speed of the variable frequency vacuum pump group, the speed of the differential centrifuge, and the amount of flocculant added based on the sensor fusion data to match the characteristics of septic tank sludge under different operating conditions.

2. The multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system according to claim 1, characterized in that, It also includes a solid-liquid mixture pre-homogenization module, which is located between the vacuum buffer tank and the primary coarse separation module and has a built-in shear homogenizer. The shear homogenizer applies shear stirring to the solid-liquid mixture before it enters the primary coarse separation module to break up large agglomerates and uniformly disperse solid particles in the liquid phase. The rotational speed of the shear homogenizer is determined according to the following adaptive homogenization control law: In the formula This refers to the real-time rotational speed of the homogenizer. The reference speed for the homogenizer. This is the homogeneous strength adjustment coefficient. For the actual measurement of solid phase concentration by sensor array, This is the standard value for solid phase concentration.

3. The multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system according to claim 1, characterized in that, It also includes an energy recovery and self-sustaining module, which includes a solar photovoltaic panel array, an energy storage battery pack, and an energy management circuit. The solar photovoltaic panel array is laid on the top of the vehicle chassis platform and charges the energy storage battery pack through the energy management circuit. In field operation scenarios without external mains power, the energy storage battery pack independently supplies power to the vacuum suction unit, the multi-stage solid-liquid separation unit, and the intelligent control unit. The energy management circuit monitors the state of charge of the energy storage battery pack in real time and automatically switches to the vehicle chassis engine power take-off mode when the state of charge is lower than a preset threshold to achieve uninterrupted continuous operation.

4. The multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system according to claim 1, characterized in that, The rotary screen solid-liquid separator of the primary coarse separation module adopts a multi-stage variable aperture screen combination. The screens are arranged sequentially along the material flow direction, with the first screening section, the second screening section, and the third screening section. The aperture of the screens in each screening section decreases progressively, and the ratio of the aperture of adjacent screens satisfies the following gradation relationship: In the formula For the first The aperture size of the sieve in the screening section, For the first The aperture size of the sieve in the screening section, The pore size reduction factor is the particle size cut-off in the first screening stage. Large impurities, the particle size retained in the second screening stage is between to Medium impurities, the particle size cutoff in the third screening stage is between to Fine impurities and unretained liquid phase mixtures are separated and enter the secondary fine separation module through the outlet of the third screening section.

5. The multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system according to claim 1, characterized in that, The differential centrifuge of the secondary fine separation module includes an inner rotating drum and an outer rotating drum coaxially mounted. The inner rotating drum rotates at a first angular velocity. The rotation generates a primary centrifugal field that causes suspended particles larger than the critical particle size to settle outwards. The outer rotating cylinder rotates at a second angular velocity. The reverse rotation creates a differential shear flow field to peel off the organic colloidal layer attached to the surface of the particles. The inner and outer rotating cylinders rotate in opposite directions and the first angular velocity is greater than the second angular velocity. The bottom of the differential centrifuge is equipped with an adjustable sludge discharge gate valve. The opening degree of the adjustable sludge discharge gate valve is adjusted in a closed loop by the intelligent control unit based on the real-time feedback from the sludge level sensor in the sludge storage hopper.

6. The multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system according to claim 1, characterized in that, The membrane flux in the submerged ultrafiltration membrane module of the three-stage deep treatment module is periodically adjusted via online backwashing according to the following membrane fouling control law: In the formula This refers to the real-time membrane flux of the ultrafiltration membrane. The initial membrane flux for cleaning the membrane, The membrane fouling attenuation coefficient is... This is the real-time measured value of the transmembrane pressure difference. For the total resistance of the filter cake layer on the membrane surface, when decay to When the preset ratio is below a certain threshold, the intelligent control unit triggers the backwash pump to perform pulsed backwashing on the ultrafiltration membrane module to restore membrane flux.

7. The multi-stage solid-liquid separation vehicle-mounted intelligent septic tank cleaning and treatment system according to claim 1, characterized in that, The adaptive cleaning strategy module of the intelligent control unit internally runs a multi-objective parameter coordination algorithm based on fuzzy inference. The multi-objective parameter coordination algorithm takes maximizing the overall efficiency of solid-liquid separation, minimizing the energy consumption per unit of treatment, and achieving the standard of effluent turbidity as three optimization sub-objectives. It constructs a working condition feature vector by collecting liquid level, turbidity, flow rate, solid concentration, and pressure parameters in real time through a multi-parameter sensor array. A fuzzy inference rule base is established between the working condition feature vector and the optimization sub-objectives. Based on the membership degree of the real-time working condition feature vector, it dynamically outputs speed adjustment commands for the variable frequency vacuum pump group, frequency adjustment commands for the differential centrifuge, and flow rate adjustment commands for the flocculant dosing pump.

8. A method for intelligent cleaning and treatment of multi-stage solid-liquid separation vehicle-mounted septic tanks, applicable to the intelligent cleaning and treatment system for multi-stage solid-liquid separation vehicle-mounted septic tanks as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: Once the vehicle chassis platform is in place, drive it to the target septic tank operation location and lock the parking brake. Extend the retractable suction pipe and lower the suction port to a preset depth below the septic tank liquid level. Step 2: Vacuum suction. The intelligent control unit sends a start command to the variable frequency vacuum pump set. After the variable frequency vacuum pump set establishes a vacuum by operating at an initial low frequency, it gradually increases the frequency to the target suction frequency based on the feedback from the pressure sensor in the vacuum buffer tank. The solid-liquid mixture in the septic tank is then suctioned into the vacuum buffer tank through the suction pipe and buffered. Step 3: Primary coarse separation. The solid-liquid mixture in the vacuum buffer tank enters the rotary screen solid-liquid separator under the combined action of gravity and vacuum residual pressure. The rotary screen solid-liquid separator rotates at a preset speed to screen and retain large-particle solid impurities. The retained solids are discharged into the solid residue collection bin through a screw conveyor mechanism. The liquid phase mixture flows out from the screen outlet and enters the secondary fine separation module. Step 4: Secondary fine separation. After the liquid mixture enters the differential centrifuge, the inner and outer rotating drums rotate in opposite directions at different speeds, creating a combined force field environment of centrifugal sedimentation field and shear stripping field. Under the action of the combined force field, fine particulate suspended matter settles to the cylinder wall to form a concentrated sludge layer, which is discharged into the sludge temporary storage hopper through the adjustable sludge discharge gate valve. The supernatant is discharged from the overflow port at the top of the differential centrifuge and enters the tertiary deep treatment module. Step 5: The supernatant enters the flocculation stirring reactor and is mixed with the flocculant dosage commanded by the intelligent control unit to generate flocs. The mixture containing flocs enters the submerged ultrafiltration membrane module and is separated from the water by membrane separation under the drive of transmembrane pressure difference. The water is discharged through the effluent pipe in compliance with standards or recycled. Step Six: Intelligent Closed-Loop Control. Throughout the entire operation process from Step Two to Step Five, the intelligent control unit continuously collects the operating parameters of each separation module through a multi-parameter sensor array and runs the adaptive cleaning strategy module to perform online rolling optimization and adjustment of the control quantities of each actuator to adapt to the real-time changes in the characteristics of sludge in the septic tank.

9. The intelligent cleaning and treatment method for a multi-stage solid-liquid separation vehicle-mounted septic tank according to claim 8, characterized in that, In step five, the determination of the flocculant dosage adopts a feedforward and feedback combined control strategy based on influent turbidity and flow rate. The feedforward part calculates the basic dosage based on influent turbidity and flow rate, while the feedback part makes real-time corrections based on the effluent turbidity deviation. The real-time flow command of the flocculant dosing pump is determined by the following formula: In the formula This is the real-time flow command for the flocculant dosing pump. This is the feedforward addition coefficient. This refers to the real-time flow rate of the supernatant entering the flocculation stirred reactor. The real-time turbidity of the supernatant entering the flocculation stirred reactor. To ensure that the turbidity of the effluent meets the discharge standard value, For feedback correction coefficient, For the turbidity of the effluent at time Real-time detection values, This refers to the current moment.

10. The intelligent cleaning and treatment method for a multi-stage solid-liquid separation vehicle-mounted septic tank according to claim 8, characterized in that, The first angular velocity of the inner rotating drum of the differential centrifuge in step four. With the second angular velocity of the outer rotating cylinder The intelligent control unit performs coordinated adaptive adjustment based on the solid concentration and flow rate of the liquid mixture entering the differential centrifuge. When the solid concentration of the liquid mixture increases, the absolute difference between the first angular velocity of the inner drum and the second angular velocity of the outer drum is increased simultaneously to enhance the centrifugal sedimentation driving force. When the solid concentration of the liquid mixture decreases, the absolute difference between the first angular velocity of the inner drum and the second angular velocity of the outer drum is decreased simultaneously.

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