A greywater recycling and control system and method

Abstract

This invention discloses a greywater recycling and control system and method, relating to the field of greywater control technology. By analyzing the operational status of multiple interconnected bioreactors, all bioreactors are categorized into sets A, B, and C based on the analysis results. Bioreactors in set A are shut down. After intelligently controlling the circulation frequency and treatment volume of bioreactors in set B, control commands are output to the bioreactors from sets B and C. Based on these control commands, greywater from the equalization tank is pumped to the bioreactors for treatment. The treated greywater is then transferred to a clear water tank for disinfection and reuse. The control system optimizes the management of bioreactors in different states, adjusting the circulation frequency and water volume distribution of the supported reactors to ensure a balanced load on the entire system, improve water treatment efficiency, and avoid unnecessary resource waste.

Description

Technical Field

[0001] This invention relates to the field of greywater regulation technology, specifically to a greywater recycling and regulation system and method. Background Technology

[0002] Water is an indispensable basic resource for campus life and daily activities. With the increasing awareness of environmental protection and the aggravation of water shortage, the rational use and management of water resources has become increasingly important. In order to improve the efficiency of water resource utilization, save water, and reduce the discharge of greywater, more and more campuses are beginning to implement water recycling and reuse systems.

[0003] The existing technology has the following drawbacks:

[0004] Traditional greywater treatment systems typically lack sophisticated bioreactor status monitoring and management mechanisms, which can lead to reduced treatment efficiency due to uneven operation of the bioreactors. For example, if some reactors are overloaded while others are underloaded, the performance of some reactors will deteriorate, ultimately affecting the overall greywater treatment effect.

[0005] Based on this, the present invention proposes a greywater recycling and control system and method to optimize the management of bioreactors in different states, adjust the number of cycles and water distribution of the supporting reactors, ensure the load balance of the entire system, improve water treatment efficiency, and avoid unnecessary waste of resources. Summary of the Invention

[0006] The purpose of this invention is to provide a greywater recycling and regulation system and method to address the shortcomings of the prior art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for regulating the recycling and reuse of greywater, the method comprising the following steps:

[0008] The water collection equipment collects the greywater and pre-filters it. The pre-filtered greywater then enters the equalization tank for water quantity and quality adjustment.

[0009] The operational status of multiple interconnected bioreactors is analyzed. Based on the analysis results, all bioreactors are assigned to sets A, B, and C respectively, and the bioreactors in set A are shut down.

[0010] After intelligently controlling the number of cycles and the amount of water treated in the bioreactor in set B, the set B and set C output control commands to the bioreactor. Based on the control commands, the reclaimed water in the equalization tank is lifted to the bioreactor for treatment by a booster pump. The treated reclaimed water is then transferred to the clear water tank for disinfection and is ready for use.

[0011] In a preferred embodiment, the operational status analysis of multiple interconnected bioreactors includes the following steps:

[0012] Obtain the water distribution flow rate deviation, membrane flux accumulation factor, and air flow rate fluctuation amplitude of the bioreactor;

[0013] The anomaly index of the bioreactor is obtained by comprehensively calculating the water distribution flow rate deviation, membrane flux accumulation factor, and air flow rate fluctuation amplitude of the aeration device. The expression is as follows:

[0014] In the formula, Jer is the anomaly index, F_Dev is the membrane flux accumulation factor, S_Dev is the water distribution flow rate deviation, and α, β, and γ are the air flow rate fluctuation amplitude of the aeration device. α, β, and γ are adjustment coefficients, and all three are greater than 0.

[0015] In a preferred embodiment, based on the analysis results, all bioreactors are classified into sets A, B, and C, respectively, including the following steps:

[0016] The obtained anomaly index is compared with a preset first index threshold and a second index threshold. The first index threshold is used to determine whether there is an anomaly in the operation of the bioreactor, and the second index threshold is used to determine the severity of the anomaly in the bioreactor. The first index threshold is less than the second index threshold.

[0017] If the abnormality index is less than or equal to the first index threshold, it is determined that there is no abnormality in the operation of the bioreactor, and the bioreactor is included in set C.

[0018] If the abnormality index is less than or equal to the second index threshold and greater than the first index threshold, it is determined that there is a slight abnormality in the operation of the bioreactor, and the bioreactor is classified into set B.

[0019] If the abnormality index is greater than the second index threshold, it is determined that there is a serious abnormality in the operation of the bioreactor, and the bioreactor is classified into set A.

[0020] In a preferred embodiment, intelligently controlling the number of cycles and the amount of water treated in the bioreactors of set B includes the following steps:

[0021] The water treatment capacity of bioreactors in set B is regulated using an anomaly index. The regulation algorithm expression is as follows: In the formula, sl nwe To regulate the treated water volume, sl old The amount of water to be treated before regulation. An abnormal index;

[0022] The number of cycles in the bioreactor is determined based on the adjusted treated water volume, expressed as:

[0023] In the formula, C r C0 is the current number of iterations required, C0 is the initial number of iterations, and sl is the current number of iterations required. new To regulate the treated water volume, sl old The amount of water to be treated before regulation. The rounding up symbol.

[0024] In a preferred embodiment, the control commands for the bioreactor are output from both set B and set C, including the following steps:

[0025] Obtain the number of bioreactors in set C and set B. Prioritize the use of bioreactors in set C. If the operation of bioreactors in set C meets the wastewater treatment efficiency of the control system, then bioreactors in set B will not be activated. If the operation of bioreactors in set C does not meet the wastewater treatment efficiency of the control system, then allocate workload to each bioreactor in set B based on the controlled treated water volume and the number of cycles.

[0026] In a preferred embodiment, the control system obtains an acceptable value by subtracting the current expected wastewater treatment efficiency from the expected wastewater treatment efficiency. If the acceptable value is less than or equal to the acceptable threshold, it indicates that the decline in wastewater treatment efficiency is still within the acceptable range. If the acceptable value is greater than the acceptable threshold, it indicates that the decline in wastewater treatment efficiency is not within the acceptable range, and the control system sends a warning signal to the relevant management personnel.

[0027] In a preferred embodiment, the calculation expression for the water distribution flow rate deviation is: In the formula, F_Dev is the water distribution flow rate deviation, and Q total Q represents the total water flow rate of the water distribution device. i Let n be the water flow rate at the i-th water inlet, and n be the number of water inlets.

[0028] The formula for calculating the membrane flux accumulation factor is as follows: In the formula, is the membrane flux accumulation factor, 0~t is the monitoring time period, and C p (τ) represents the membrane flux at time τ;

[0029] The calculation logic for the airflow fluctuation amplitude of the aeration device is as follows: During the monitoring period, the airflow of the aeration device is acquired at multiple time points, and the airflow fluctuation amplitude of the aeration device is calculated based on the airflow at multiple time points. The expression is: In the formula, S_Dev is the fluctuation amplitude of the air flow rate of the aeration device, m is the number of time points, and L i Let L be the air flow rate of the aeration device at the i-th time point. total This represents the total airflow of the aeration device during the monitoring period.

[0030] In a preferred embodiment, the bioreactor is a DMBR dual-membrane internal circulation bioreactor, which includes a biofilm reaction zone and a microfiltration zone. The greywater mixture forms an internal circulation in the biofilm reaction zone and the microfiltration zone through the action of aeration airflow. The biofilm reaction zone is equipped with a water distribution device, biofilm packing material, aeration device and air inlet electric valve, and the microfiltration zone is equipped with an immersion microfiltration membrane module, aeration and flushing device and air inlet electric valve.

[0031] In a preferred embodiment, the workflow of the DMBR dual-membrane internal circulation bioreactor is as follows:

[0032] The mixed wastewater is evenly introduced into the biofilm reaction zone through the water distribution device. The air inlet electric valve of the packing biofilm reaction zone is opened intermittently to alternately form an anaerobic-anoxic-aerobic environment, completing the aerobic nitrification phosphorus uptake, anoxic denitrification reaction, and anaerobic phosphorus release reaction of microorganisms.

[0033] After the reaction, the mixed liquid of wastewater forms an internal circulation under the action of airflow. It flows through the microfiltration membrane filtration zone, where the detached biofilm and particulate matter are intercepted by the microfiltration membrane and returned to the biofilm reaction zone with the water flow. The clean water passes through the microfiltration membrane module and flows into the clean water pool.

[0034] A greywater recycling and control system includes a pre-filtration unit, a greywater regulation unit, a reactor assembly division unit, and an intelligent regulation unit;

[0035] Pre-filtration unit: used to collect and pre-filter greywater;

[0036] Greywater regulation unit: used to regulate the quantity and quality of greywater;

[0037] Reactor set division unit: The operating status of multiple interconnected bioreactors is analyzed, and based on the analysis results, all bioreactors are divided into sets A, B and C respectively;

[0038] Intelligent regulation unit: shuts down the bioreactor in set A, and after intelligently regulating the number of cycles and the amount of water treated in the bioreactor in set B, it combines the control commands of sets B and C to output control commands to the bioreactor. According to the control commands, the reclaimed water in the regulating tank is lifted to the bioreactor for treatment by a lift pump. The treated reclaimed water is then disinfected and kept on standby.

[0039] The technical effects and advantages provided by the present invention in the above technical solution are as follows:

[0040] This invention analyzes the operational status of multiple interconnected bioreactors. Based on the analysis results, all bioreactors are categorized into sets A, B, and C. Bioreactors in set A are shut down. After intelligently controlling the circulation frequency and treatment volume of bioreactors in set B, control commands are output from sets B and C to the bioreactors. Following these commands, reclaimed water from the equalization tank is pumped to the bioreactors for treatment. The treated reclaimed water is then transferred to a clear water tank for disinfection and reuse. The control system optimizes the management of bioreactors in different states, adjusting the circulation frequency and water volume distribution of the supported reactors to ensure a balanced load on the entire system, improve water treatment efficiency, and avoid unnecessary resource waste. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0042] Figure 1 This is a flowchart of the method of the present invention.

[0043] Figure 2 This is a flowchart illustrating the workflow of the bioreactor in this invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0045] Example 1: Please refer to Figure 1 As shown in this embodiment, a method for regulating and controlling the recycling of greywater includes the following steps:

[0046] The water collection equipment gathers and pre-filters greywater. Greywater sources include swimming pool drainage, rainwater, and greywater from new buildings. The collection equipment filters large particles (such as leaves and plastic) from the greywater through a two-stage basket screen to prevent clogging of subsequent equipment. The pre-filtered greywater enters a regulating tank for flow and quality adjustment, ensuring relatively stable water quality and quantity during subsequent treatment processes and guaranteeing consistent treatment results. Operational status analysis is performed on multiple interconnected bioreactors. Based on the analysis results, all bioreactors are assigned to groups A, B, and C. Bioreactors in group A are shut down. After intelligent control of the circulation frequency and treatment volume of bioreactors in group B, control commands are output to the bioreactors from groups B and C. Based on these commands, greywater from the regulating tank is pumped to the bioreactors for treatment. The treated greywater is then transferred to a clear water tank for disinfection and reuse. Disinfection is performed using ultraviolet light, ozone, or sodium hypochlorite to kill pathogenic microorganisms and ensure water safety. Reusable water is used for campus greening irrigation, toilet flushing, road cleaning, etc., while the remaining portion can be safely discharged into natural water bodies.

[0047] This application analyzes the operational status of multiple interconnected bioreactors. Based on the analysis results, all bioreactors are categorized into sets A, B, and C. Bioreactors in set A are shut down. After intelligently controlling the circulation frequency and treatment volume of bioreactors in set B, control commands are output from sets B and C to the bioreactors. Based on these commands, reclaimed water from the equalization tank is pumped to the bioreactors for treatment. The treated reclaimed water is then transferred to a clear water tank for disinfection and reuse. The control system optimizes the management of bioreactors in different states, adjusting the circulation frequency and water volume distribution of the supported reactors to ensure a balanced load on the entire system, improve water treatment efficiency, and avoid unnecessary resource waste.

[0048] Example 2: The water collection equipment collects and pre-filters greywater. The greywater sources include swimming pool drainage, rainwater, and greywater from new buildings. The water collection equipment filters large particulate impurities (such as leaves, plastic, etc.) in the greywater through a two-stage basket screen to prevent clogging of subsequent equipment. The process includes the following steps:

[0049] Water collection equipment is responsible for collecting greywater from various sources, and mainly includes the following categories:

[0050] Swimming pool drainage: Water from the school swimming pool contains certain amounts of chlorides, chemicals, and impurities.

[0051] Rainwater: Rainwater collected from school rooftops, roads and other paved surfaces contains solid particles such as dust and silt.

[0052] Wastewater from new buildings: Reclaimed water from new buildings on campus may include domestic wastewater, bathing water, etc., and contains low concentrations of organic matter and suspended solids.

[0053] The greywater from these different sources is collected in a unified collection tank through a dedicated pipeline system. The main function of the collection tank is to temporarily store the water to be treated, providing a stable water source for subsequent treatment processes. Through sedimentation within the collection tank, larger particles (such as sand and impurities) will naturally settle, playing a preliminary role in water quality regulation.

[0054] The water flowing into the collection tank first passes through a primary basket screen. This process primarily captures larger particles of impurities in the water, such as organic debris from rainwater or swimming pool drainage, household waste from the campus environment, and sediments that may be mixed with rainwater or wastewater from new buildings. The primary basket screen has relatively large mesh openings, typically designed with a pore size of 5-10 mm, to effectively prevent larger impurities from entering the next stage of treatment. As the water flows through the screen, larger impurities are physically intercepted and periodically removed by mechanical cleaning.

[0055] After passing through the primary screen, the water enters the secondary basket screen. This stage primarily removes smaller solid particles from the water, such as fine organic matter, which is further removed by the secondary screen. These small, non-biological impurities may have passed through the primary screen but remain in the water flow, requiring further removal by the secondary screen. The pore size of the secondary basket screen is finer than that of the primary screen, typically designed to be 1-5 mm, to ensure the further removal of small impurities. The interception effect of the secondary screen effectively prevents fine particles from entering subsequent treatment systems.

[0056] The coarse particles removed by the primary screen make the water flow relatively clean, reducing the burden on subsequent equipment. The secondary screen further removes fine particles, ensuring that the water quality is not affected by small impurities, thus avoiding equipment blockage, damage, and increased maintenance frequency.

[0057] To ensure the filtration effectiveness of the primary and secondary screens, it is necessary to regularly clean the accumulated impurities on the screens to prevent clogging, obstruction of water flow, and ensure long-term stable operation. Sensors are installed in the screen system to monitor water flow and screen clogging status in real time, automatically performing cleaning or maintenance as needed.

[0058] Through two-stage bar filtration, the vast majority of larger particulate impurities in the water flow have been removed, significantly improving water quality. At this point, the water enters the subsequent treatment stage, where the solid particle content has been reduced to a low level, laying the foundation for subsequent biological treatment and disinfection steps. This meticulous pre-filtration process ensures that subsequent equipment in the water treatment system (such as bioreactors, pump systems, and pipelines) is less affected by excessive impurities, thereby reducing equipment failure rates and maintenance costs.

[0059] By meticulously designing the water source access, collection tank storage, and two-stage bar filtration process, this application effectively removes large particulate impurities from the water, ensuring the normal operation of subsequent equipment and preventing equipment malfunctions or performance degradation caused by impurities in the water source. Simultaneously, a refined water quality monitoring and real-time feedback mechanism is employed during the pre-filtration process to ensure the stability of system operation and the controllability of water quality, providing a high-quality greywater source for subsequent bioreactor treatment and disinfection.

[0060] The pre-filtered reclaimed water enters the equalization tank for water quantity and quality adjustment, ensuring relatively stable water quality and quantity in subsequent treatment processes and guaranteeing consistent treatment results. This includes the following steps:

[0061] After passing through two stages of bar filtration, the treated water is guided into the equalization tank. At this point, large particulate impurities have been removed from the water source, and the water quality is relatively clean, but further equalization is still needed to ensure the stability of subsequent treatment. The main function of the equalization tank is to provide a uniform and stable water source for subsequent treatment, avoiding excessive fluctuations in water quality and uneven water volume that could affect the treatment effect.

[0062] The equalization tank acts as a buffer zone, balancing fluctuations in water flow from different sources (such as swimming pool drainage, rainwater, and wastewater from new buildings). When the inflow from a particular source is large, the equalization tank can temporarily store some water, mitigating sudden surges and preventing overload of pumps and treatment equipment. If the water level in the equalization tank is too high, the excess water is automatically discharged to prevent excessive pressure on downstream equipment; if the water level is too low, the system regulates the water flow through valves to ensure the water level in the equalization tank remains within a reasonable range.

[0063] Natural sedimentation occurs within the equalization tank, where smaller particles and suspended solids gradually settle, further improving water quality. The water retention time in the equalization tank (typically several hours) allows fine particles to settle to the bottom, reducing their likelihood of entering the subsequent bioreactor. If necessary, appropriate amounts of conditioning agents, such as flocculants or coagulants, may be added to the equalization tank to further remove fine particles or colloidal substances and improve water quality. The dosage of these agents is automatically adjusted based on water quality monitoring results to avoid over- or under-dosing. pH adjusters can also be added to the equalization tank to ensure a suitable acidity or alkalinity. Water that is too acidic or too alkaline will affect the subsequent bioreactor and disinfection process; therefore, it is essential to ensure the water's pH value is within the appropriate range.

[0064] In some highly seasonal regions, temperature fluctuations can affect the activity of microorganisms in the water, thereby impacting the treatment efficiency of subsequent bioreactors. The water temperature in the equalization tank can be appropriately regulated using devices such as temperature regulators or heating systems to ensure it remains within the optimal range. Temperature sensors in the system monitor the water temperature in real time and automatically adjust it via heaters or cooling equipment to ensure the water enters the bioreactor at a suitable temperature.

[0065] The equalization tank is equipped with multiple sensors to monitor water quality parameters in real time, such as turbidity, dissolved oxygen, pH, temperature, and suspended solids concentration. This data is fed back to the central control system, which automatically adjusts the treatment process based on water quality changes to ensure water quality stability. The system identifies water quality fluctuation trends through data analysis and automatically adjusts reagent dosage, discharge volume, and water flow control to ensure that the water quality in the equalization tank consistently meets the requirements for entering the bioreactor.

[0066] The water quantity and quality regulation process in the equalization tank is fully automated by an intelligent control system. Through advanced algorithms, the system can predict future demand based on real-time water quantity and quality parameters, as well as historical data, and automatically adjust the water flow and quality regulation measures within the equalization tank. The operating status of the equalization tank can be viewed in real-time through a remote monitoring system. Operators can adjust the operating settings of the equalization tank as needed, or intervene promptly based on abnormal alarms.

[0067] The water treated in the equalization tank will have a relatively stable quantity and quality, ensuring consistency in both when it enters the subsequent bioreactors. This stability is fundamental to guaranteeing the normal operation of the bioreactors and the consistency of treatment results. With stable quantity and quality, the equalization tank can effectively distribute the water flow to each bioreactor, preventing any single reactor from being overloaded or experiencing a decrease in treatment efficiency, thereby improving overall treatment efficiency.

[0068] Operational status analysis of multiple interconnected bioreactors includes the following steps:

[0069] Obtain the water distribution flow rate deviation, membrane flux accumulation factor, and air flow rate fluctuation amplitude of the bioreactor;

[0070] The anomaly index of the bioreactor is obtained by comprehensively calculating the water distribution flow rate deviation, membrane flux accumulation factor, and air flow rate fluctuation amplitude of the aeration device. The expression is as follows:

[0071] In the formula, The abnormality index is defined as follows: Jer is the membrane flux accumulation factor, F_Dev is the water distribution flow deviation, S_Dev is the air flow fluctuation amplitude of the aeration device, and α, β, and γ are adjustment coefficients, all of which are greater than 0. The abnormality index comprehensively considers the water distribution flow deviation, the membrane flux accumulation factor, and the air flow fluctuation amplitude of the aeration device. The larger the abnormality index, the worse the overall performance of the bioreactor.

[0072] The formula for calculating the water distribution flow rate deviation is: In the formula, F_Dev is the water distribution flow rate deviation, and Q total Q represents the total water flow rate of the water distribution device. i Let be the water flow rate at the i-th water outlet, and n be the number of water outlets. A large deviation in water flow rate indicates that the distribution of the water distribution device is uneven, which leads to uneven distribution of water flow in the reactor, affecting the contact efficiency of microorganisms and the removal efficiency of pollutants.

[0073] The formula for calculating the membrane flux accumulation factor is: In the formula, is the membrane flux accumulation factor, 0~t is the monitoring time period, and C p (τ) represents the membrane flux at time τ;

[0074] A decrease in membrane flux is generally proportional to the degree of membrane fouling. When the membrane surface is fouled by solid particles, bacteria, or organic matter, the membrane pores become clogged, reducing water permeability. Therefore, a decrease in membrane flux is usually an indicator of severe membrane fouling. Membrane fouling not only reduces filtration capacity but also increases system energy consumption, leading to a decrease in treated water volume. Bioreactors use membrane filtration to treat solid particles and impurities in water; a decrease in membrane flux means a reduction in the amount of water passing through the membrane per unit time, resulting in decreased treatment efficiency. When the membrane flux is too low, the overall treatment capacity of the reactor is also limited, affecting both the volume and quality of treated water. Therefore, a decrease in membrane flux directly leads to a decline in the overall performance of the bioreactor.

[0075] As membrane flux decreases, the system requires higher pressure to force water through the membrane, thus increasing energy consumption. To maintain the same treatment capacity, the system needs a larger pressure differential, which not only increases energy consumption but also leads to equipment wear and failure. Therefore, reduced membrane flux increases the operating cost and energy consumption of the bioreactor, further reducing overall performance. Decreased membrane flux means poorer filtration, and fine particles, suspended solids, and contaminants in the water may not be effectively removed. This leads to water quality deterioration, making it impossible for subsequent treatment processes to guarantee water safety and stability. Reduced membrane flux can also cause decreased system stability. Due to membrane fouling, the reactor requires more frequent cleaning cycles to maintain membrane lifespan. Frequent cleaning leads to intermittent and unstable system operation, affecting the continuity and stability of water treatment.

[0076] Lower membrane flux indicates more severe membrane fouling, reduced filtration efficiency, decreased water treatment capacity, increased energy consumption, poorer water quality control, and reduced system stability. Therefore, a decrease in membrane flux is a significant indicator of overall reactor performance decline. This phenomenon reflects increased membrane fouling, clogging, and operational burden, all of which prevent the bioreactor from maintaining efficient and stable operation.

[0077] The calculation logic for the airflow fluctuation amplitude of the aeration device is as follows: During the monitoring period, the airflow of the aeration device is acquired at multiple time points. Based on the airflow at these multiple time points, the airflow fluctuation amplitude of the aeration device is calculated. The expression is: In the formula, S_Dev is the fluctuation amplitude of the air flow rate of the aeration device, m is the number of time points, and L i Let L be the air flow rate of the aeration device at the i-th time point. total This represents the total airflow of the aeration device during the monitoring period.

[0078] The airflow rate of the aeration device plays a crucial role in the cleaning process of microfiltration membranes. Excessive or insufficient airflow can lead to incomplete cleaning of the membrane surface, preventing the effective removal of accumulated contaminants. Larger fluctuations in airflow rate indicate increased instability in membrane surface cleaning. This means that insufficient airflow at certain times exacerbates membrane fouling, while excessive airflow at other times can cause over-rinsing, leading to membrane damage or uneven rinsing. Greater fluctuations in airflow rate result in poorer cleaning stability, increased membrane fouling, decreased membrane flux, and ultimately, impacted reactor performance.

[0079] Aeration devices in bioreactors not only clean the membrane but also supply oxygen to the microorganisms, especially during the aerobic reaction stage. Instability in oxygen supply (i.e., excessive airflow fluctuations) leads to unstable metabolic activity of the microorganisms within the reactor. Insufficient oxygen reduces microbial activity and results in poor treatment efficiency; while excessive airflow may increase oxygen supply, it can also lead to energy waste. The greater the airflow fluctuation amplitude, the more unstable the oxygen supply and microbial activity, resulting in decreased bioreactor treatment efficiency and impacting reactor performance. Airflow fluctuations in the aeration device not only affect the bioreactor's treatment efficiency but also increase energy consumption. To maintain stable treatment efficiency, the reactor may need to constantly adjust the airflow and frequently regulate the aeration device's power, leading to unnecessary energy consumption. Larger airflow fluctuations and higher adjustment frequencies result in greater energy consumption. Larger airflow fluctuation amplitudes and more frequent airflow adjustments increase energy consumption and may also increase system wear, affecting the long-term stable operation of the equipment.

[0080] Fluctuations in airflow can also affect the operational stability of the entire bioreactor. Large fluctuations in airflow can lead to uneven reactor operation, causing overload during certain periods and insufficient airflow at others. This instability not only affects the treated water volume but can also prevent the reactor from efficiently handling fluctuating influent water quality. The greater the amplitude of airflow fluctuations, the more unstable the reactor's operating load, resulting in poor treatment process stability and a decline in bioreactor performance. Airflow fluctuations can also lead to unstable reactor water quality. Insufficient oxygen supply reduces the metabolic capacity of microorganisms, leading to incomplete degradation of organic matter and deteriorating water quality; conversely, excessive airflow can cause over-aeration, potentially affecting dissolved oxygen levels and thus water quality. The greater the amplitude of airflow fluctuations, the greater the instability of water treatment effects, leading to decreased water quality control capabilities and further impacting the overall performance of the bioreactor.

[0081] Based on the analysis results, all bioreactors were classified into sets A, B, and C, including the following steps:

[0082] The anomaly index takes into account the deviation of water distribution flow rate, the cumulative factor of membrane flux, and the fluctuation amplitude of air flow rate of aeration device. The larger the anomaly index, the worse the overall performance of the bioreactor.

[0083] The obtained anomaly index is compared with a preset first index threshold and a second index threshold. The first index threshold is used to determine whether there is an anomaly in the operation of the bioreactor, and the second index threshold is used to determine the severity of the anomaly in the bioreactor. The first index threshold is less than the second index threshold.

[0084] If the abnormality index is less than or equal to the first index threshold, it is determined that there is no abnormality in the operation of the bioreactor, and the bioreactor is included in set C.

[0085] If the abnormality index is less than or equal to the second index threshold and greater than the first index threshold, it is determined that there is a slight abnormality in the operation of the bioreactor, and the bioreactor is classified into set B.

[0086] If the anomaly index is greater than the second index threshold, it is determined that there is a serious anomaly in the operation of the bioreactor. The bioreactor is then classified into set A. Bioreactors in set A do not support operation and need to be shut down.

[0087] The intelligent control of the bioreactor's cycle count and water treatment volume in set B includes the following steps:

[0088] In set B, the overall performance of the bioreactors is slightly reduced, but still supports use;

[0089] Therefore, in order to ensure the stability of the operation of the bioreactors in set B, it is necessary to reduce the amount of water that the bioreactors in set B can process at one time and increase the number of cycles of the bioreactors.

[0090] In this application, the water treatment capacity of bioreactors in set B is regulated by an anomaly index. The regulation algorithm expression is as follows: In the formula, sl new To regulate the treated water volume, sl old The amount of water to be treated before regulation. An abnormal index;

[0091] The number of cycles in the bioreactor is determined based on the adjusted treated water volume, expressed as:

[0092] In the formula, C r C0 is the current number of iterations required, C0 is the initial number of iterations, and sl is the current number of iterations required. new To regulate the treated water volume, sl old The amount of water to be treated before regulation. The 'Ceiling' symbol is used for rounding up. The operation is called 'Ceiling' and represents the smallest integer greater than or equal to itself. For example, 1.2 rounded up becomes 2, and so on.

[0093] Combining the control commands for the bioreactor from set B and set C, the steps include:

[0094] Obtain the number of bioreactors in set C and set B. Prioritize the use of bioreactors in set C. If the operation of bioreactors in set C meets the water treatment efficiency of the control system, then bioreactors in set B will not be activated. If the operation of bioreactors in set C does not meet the water treatment efficiency of the control system, then allocate the workload to each bioreactor in set B based on the treated water volume and the number of cycles after regulation, until the water treatment efficiency of the control system is met.

[0095] In practical applications, it may happen that even if all bioreactors in set C and set B operate simultaneously, they cannot meet the wastewater treatment efficiency requirements of the control system (usually due to an insufficient number of bioreactors in sets C and B). We obtain the acceptable value by subtracting the current expected wastewater treatment efficiency from the expected wastewater treatment efficiency. If the acceptable value is less than or equal to the acceptable threshold, it indicates that the decline in wastewater treatment efficiency is still within the acceptable range. If the acceptable value is greater than the acceptable threshold, it indicates that the decline in wastewater treatment efficiency is not within the acceptable range, and the control system sends a warning signal to the relevant management personnel.

[0096] If the number of bioreactors in set C is insufficient to meet the system's wastewater treatment needs, then the treatment capacity needs to be supplemented by reactors in set B whose performance has declined. In this case, we need to redesign the bioreactor combination scheme so that the system can maximize the performance of each reactor while ensuring water quality safety.

[0097] There are k bioreactors. Set A has a bioreactors (which are shut down), set B has b bioreactors (whose performance has deteriorated and requires adjustment of water volume and increase of circulation frequency), and set C has kba bioreactors (which have the best performance, but the number is insufficient to meet the needs of each individual bioreactor).

[0098] Assume the volume of greywater we need to process is F_total (assuming it is 20m³). 3 / h), set C can only provide the processing capacity of F_C, and the remaining part needs to be supplemented by the bioreactors in set B.

[0099] Set C has an insufficient number of reactors, but it can still provide some processing capacity. Assume set C has 2 reactors, and each reactor has a maximum processing capacity of 10m³. 3 / h, F_C=10m 3 / h*2=20m 3 / h (at this point, set C has provided all the processing capacity required by the system), however, in practical applications, the number of reactors in set C is often insufficient to meet the demand, or further adjustments are required.

[0100] Assume set C can only provide 15m 3 / h (for example, set C has only 1 reactor), in this case, set B needs to be relied upon to supplement the remaining processing capacity. Assume set B has 3 reactors, each with a processing capacity of 8m³ / h under normal conditions. 3 / h, but due to performance degradation, adjustments are needed to reduce water volume and increase the number of cycles.

[0101] Option 1: Fully activate some reactors in set B.

[0102] Set C: Provides 15m 3 / h processing capacity. Set B: Remaining water volume to be treated is 5m³. 3 / h. Select one or more reactors to adjust and supplement. Assume that the initial treatment capacity of reactor B1 (reactor 1 in set B) is 8m³. 3 / h, after performance degrades, adjust water flow to 4m 3 / h, increase the number of cycles to compensate for the performance loss. Assume that B1 can reach 5m after adjustment. 3 / h processing capacity.

[0103] Example 1: Adjusted combination scheme

[0104] Set C: Reactor C1 provides 15m 3 / h processing capacity. Unit B: Reactor B1 provides 5m³ / h processing capacity. 3 The / h processing capacity, after adjustment, is sufficient to compensate for any shortfall in water volume and circulation frequency. At this point, F_total = 15 + 5 = 20m³. 3 / h, meeting the processing requirements.

[0105] Option 2: Activate multiple cluster B reactors

[0106] If multiple reactors in set B can provide partial processing capacity, we can coordinate and regulate multiple reactors to meet the demand. Assume set B has 3 reactors, each with a maximum processing capacity of 8m³. 3 / h. Set C: Provides 12m 3 / h processing capacity (e.g., in set C there are two reactors, one of which malfunctions and cannot operate at full capacity). Set B: The remaining water volume to be treated is 8m³. 3 / h. Adjust the reactors in set B to ensure the system can process 8m³. 3 Water flow rate per hour: Assuming reactor B1 provides 4m³ / h 3 / h, reactor B2 provides 4m 3 / h, the two combined can meet 8m 3 The required flow rate per hour was adjusted based on the degree of performance degradation, and the number of cycles was increased to compensate for insufficient treatment capacity.

[0107] Example 2: Combined solution

[0108] Set C: Reactor C1 provides 12m 3 / h processing capacity. Unit B: Reactors B1 and B2 together provide 8m³ / h processing capacity. 3 / h processing capacity. At this point, F_total = 12 + 8 = 20m 3 / h, meets the processing requirements.

[0109] According to control instructions, the reclaimed water in the equalization tank is pumped to the bioreactor for treatment. The treated reclaimed water is then transferred to the clear water tank for disinfection and reuse. Disinfection is carried out using ultraviolet light, ozone, or sodium hypochlorite to kill pathogenic microorganisms in the water and ensure water quality safety. The reused water is used for purposes such as irrigation of campus green spaces, toilet flushing, and road cleaning. The remaining portion can be safely discharged into natural water bodies, including the following steps:

[0110] After pretreatment, the wastewater enters the DMBR dual-membrane internal circulation bioreactor. After aerobic aeration and biological treatment, the wastewater is pumped out through a filter membrane. The DMBR dual-membrane internal circulation bioreactor uses membrane separation equipment to retain activated sludge and macromolecular organic matter in the biochemical reaction tank.

[0111] The bioreactor in this application is a DMBR dual-membrane internal circulation bioreactor, which is an integrated treatment process with advantages such as short treatment flow, small footprint, high reaction efficiency, and good effluent quality. The DMBR dual-membrane internal circulation bioreactor is based on biofilm and immersion microfiltration membrane, adopts a specific internal structure, intermittent alternating aeration, and uses airflow to form an internal circulation. One reactor alternately forms an anaerobic-anoxic-aerobic environment to achieve the purpose of biological oxidation for nitrogen and phosphorus removal.

[0112] Please see Figure 2 As shown, the workflow of the DMBR dual-membrane internal circulation bioreactor is as follows:

[0113] ① Low-concentration organic wastewater is filtered through a screen to remove particles and debris larger than 2mm, preventing clogging of downstream equipment;

[0114] ② The low-concentration organic wastewater after passing through the screen is pumped to the DMBR dual-membrane internal circulation bioreactor.

[0115] The DMBR dual-membrane internal circulation bioreactor is divided into a biofilm reaction zone and a microfiltration zone. The greywater mixture forms an internal circulation between the two zones through the action of aeration airflow. The biofilm reaction zone is equipped with a water distribution device, biofilm packing, aeration device and air inlet electric valve. The microfiltration zone is equipped with an immersion microfiltration membrane module, aeration and flushing device and air inlet electric valve.

[0116] The greywater mixture is evenly distributed into the biofilm reaction zone through the water distribution device. The air inlet electric valve of the packing biofilm reaction zone is opened intermittently to alternately create an anaerobic-anoxic-aerobic environment, completing the aerobic nitrification and phosphorus uptake, anoxic denitrification, and anaerobic phosphorus release reactions of microorganisms, thus achieving the effect of denitrification and phosphorus removal. After the reaction, the greywater mixture forms an internal circulation under the action of airflow and flows through the microfiltration membrane filtration zone. The detached biofilm and particulate matter are intercepted by the microfiltration membrane and returned to the biofilm reaction zone with the water flow. The clear water passes through the microfiltration membrane module and flows into the clear water tank.

[0117] The DMBR dual-membrane internal circulation bioreactor organically combines the A / A / O process, biofilm method, and MBR membrane method through a series of innovations within the reactor. It fully leverages the advantages of the A / A / O process (high nitrogen and phosphorus removal efficiency), the biofilm method (low sludge production), and the MBR membrane bioreactor (high effluent quality with low organic matter and suspended solids). Compared to the individual processes mentioned above, it offers unparalleled advantages.

[0118] ① Compared with the conventional A / A / O process, the DMBR dual-membrane internal circulation bioreactor has better effluent quality, less residual sludge, and a smaller footprint.

[0119] ② Compared with conventional biofilm methods, it has better nitrogen and phosphorus removal effects, better effluent water quality, and a smaller footprint;

[0120] ③ Compared with conventional MBR membrane technology, it has better denitrification and phosphorus removal effects, and can use one gas for two purposes, resulting in lower energy consumption.

[0121] The DMBR dual-membrane internal circulation bioreactor is functionally divided into an equipment room, a composite anaerobic membrane bioreactor zone, and a composite aerobic membrane bioreactor zone. The DMBR dual-membrane internal circulation bioreactor organically combines the anoxic-anaerobic-aerobic inverted A / A / O process with the MBR membrane bioreactor system, forming two main functional zones: the composite anaerobic membrane bioreactor zone and the composite aerobic membrane bioreactor zone. These two zones form an internal circulation system through a special device, creating an anaerobic-anoxic-aerobic microbial growth environment. This environment facilitates aerobic nitrification and phosphorus uptake by microorganisms, anoxic denitrification, and anaerobic phosphorus release, achieving the goal of biological nitrogen and phosphorus removal. Water is distributed on both sides of the MBR membrane reaction zone. In the central zone, the aqueous mixture forms an internal circulation vertically under the action of the membrane flushing airflow, achieving the functions of flushing, aeration, and mixing. This multi-purpose airflow results in lower energy consumption than conventional MBRs. Special biological anchors are provided in the anoxic, anaerobic, and aerobic zones to immobilize microorganisms, thereby saving stirring energy and producing less residual sludge. The DMBR membrane reactor is equipped with special built-in devices. The core component of the DMBR membrane reaction zone uses a new type of membrane module, which has advantages such as high flux, good chemical stability, long cleaning cycle, and long service life compared with other membrane modules currently on the market.

[0122] The main design parameters of the DMBR dual-membrane internal circulation bioreactor in this application are as follows:

[0123] Sludge concentration: 4000–7000 mg / L;

[0124] Sludge loading: 0.05~0.10kgBOD5 / (kgMLSS·d);

[0125] Volumetric loading rate: 0.4~0.6kgBOD5 / (m³) 3 ·d);

[0126] Residual sludge production: Without chemical treatment, removing 1 kg of BOD5 produces 0.2–0.3 kg of sludge; with chemical treatment, it produces 0.4–0.6 kg of sludge.

[0127] Air-to-water ratio: 8-10:1 for sewage from rural towns in Guangxi;

[0128] Land area index: 0.3~0.5㎡ / (m²) 3 .d).

[0129] Example 3: The greywater recycling and control system described in this example includes a pre-filtration unit, a greywater regulation unit, a reactor assembly division unit, and an intelligent regulation unit;

[0130] Pre-filtration unit: Collects greywater and pre-filters it. Greywater sources include swimming pool drainage, rainwater and greywater from new buildings. Large particulate impurities (such as leaves, plastics, etc.) in the greywater are filtered through two-stage basket screens to prevent clogging of subsequent equipment. The pre-filtered greywater is then transferred to the greywater conditioning unit.

[0131] Greywater regulation unit: Regulates the quantity and quality of greywater to ensure that the water quality and quantity are relatively stable in subsequent treatment processes, thus guaranteeing consistent treatment results. The regulated greywater then enters the intelligent regulation unit.

[0132] Reactor Set Division Unit: Analyzes the operational status of multiple interconnected bioreactors, and based on the analysis results, assigns all bioreactors to sets A, B, and C respectively. The set division results are then sent to the intelligent control unit.

[0133] Intelligent regulation unit: After shutting down the bioreactor in set A and intelligently regulating the circulation number and treatment volume of the bioreactor in set B, it combines the control commands of sets B and C to output control commands to the bioreactor. According to the control commands, the reclaimed water in the regulating tank is lifted to the bioreactor for treatment by a booster pump. The treated reclaimed water is disinfected and then kept on standby. Disinfection is carried out using ultraviolet light, ozone, or sodium hypochlorite to kill pathogenic microorganisms in the water and ensure water quality safety. The standby water is used for campus greening irrigation, toilet flushing, road cleaning, etc., and the remaining part can be safely discharged into natural water bodies.

[0134] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0135] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0136] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for regulating and controlling the recycling of greywater, characterized in that: The control method includes the following steps: The water collection equipment collects the greywater and pre-filters it. The pre-filtered greywater then enters the equalization tank for water quantity and quality adjustment. The operational status of multiple interconnected bioreactors is analyzed. Based on the analysis results, all bioreactors are assigned to sets A, B, and C respectively, and the bioreactors in set A are shut down. After intelligently controlling the number of cycles and the amount of water treated in the bioreactor in set B, the control instructions for the bioreactor are output from set B and set C. According to the control instructions, the reclaimed water in the equalization tank is lifted to the bioreactor for treatment by the lift pump. The treated reclaimed water is then transferred to the clear water tank for disinfection and then kept for later use. Operational status analysis of multiple interconnected bioreactors includes the following steps: Obtain the water distribution flow rate deviation, membrane flux accumulation factor, and air flow rate fluctuation amplitude of the bioreactor; The anomaly index of the bioreactor is obtained by comprehensively calculating the water distribution flow rate deviation, membrane flux accumulation factor, and air flow rate fluctuation amplitude of the aeration device. The expression is as follows: In the formula, This is an abnormal index. It is the membrane flux accumulation factor. For water distribution flow deviation, This refers to the fluctuation amplitude of the air flow rate of the aeration device. , , It is the adjustment coefficient, and , , All are greater than 0; Based on the analysis results, all bioreactors were classified into sets A, B, and C, including the following steps: The obtained anomaly index is compared with a preset first index threshold and a second index threshold. The first index threshold is used to determine whether there is an anomaly in the operation of the bioreactor, and the second index threshold is used to determine the severity of the anomaly in the bioreactor. The first index threshold is less than the second index threshold. If the abnormality index is less than or equal to the first index threshold, it is determined that there is no abnormality in the operation of the bioreactor, and the bioreactor is included in set C. If the abnormality index is less than or equal to the second index threshold and greater than the first index threshold, it is determined that there is a slight abnormality in the operation of the bioreactor, and the bioreactor is classified into set B. If the abnormality index is greater than the second index threshold, it is determined that there is a serious abnormality in the operation of the bioreactor, and the bioreactor is classified into set A.

2. The method for regulating and controlling the recycling of greywater according to claim 1, characterized in that: The intelligent control of the bioreactor's cycle count and water treatment volume in set B includes the following steps: The amount of water treated by bioreactors in set B is regulated using an anomaly index. The regulation algorithm expression is as follows: In the formula, The amount of water treated after adjustment, The amount of water to be treated before regulation. An abnormal index; The number of cycles in the bioreactor is determined based on the adjusted treated water volume, expressed as: In the formula, The number of loops required at present. This is the initial number of iterations. The amount of water treated after adjustment, The amount of water to be treated before regulation. The rounding up symbol.

3. The method for regulating and controlling the recycling of greywater according to claim 2, characterized in that: Combining the control commands for the bioreactor from set B and set C, the steps include: Obtain the number of bioreactors in set C and set B. Prioritize the use of bioreactors in set C. If the operation of bioreactors in set C meets the wastewater treatment efficiency of the control system, then bioreactors in set B will not be activated. If the operation of bioreactors in set C does not meet the wastewater treatment efficiency of the control system, then allocate workload to each bioreactor in set B based on the controlled treated water volume and the number of cycles.

4. The method for regulating and controlling the recycling of greywater according to claim 3, characterized in that: The control system obtains an acceptable value by subtracting the current expected wastewater treatment efficiency from the expected wastewater treatment efficiency. If the acceptable value is less than or equal to the acceptable threshold, it indicates that the decline in wastewater treatment efficiency is still within the acceptable range. If the acceptable value is greater than the acceptable threshold, it indicates that the decline in wastewater treatment efficiency is not within the acceptable range, and the control system sends a warning signal to the relevant management personnel.

5. The method for regulating and controlling the recycling of greywater according to claim 4, characterized in that: The calculation expression for the water distribution flow rate deviation is as follows: In the formula, For water distribution flow deviation, This represents the total water flow rate of the water distribution device. For the first Water flow rate at each water inlet This refers to the number of water distribution outlets; The formula for calculating the membrane flux accumulation factor is as follows: In the formula, is the membrane flux accumulation factor. For the monitoring period, For time Membrane flux at any given time; The calculation logic for the airflow fluctuation amplitude of the aeration device is as follows: During the monitoring period, the airflow of the aeration device is acquired at multiple time points, and the airflow fluctuation amplitude of the aeration device is calculated based on the airflow at multiple time points. The expression is: In the formula, This refers to the fluctuation amplitude of the air flow rate of the aeration device. For the number of time points, For the first The air flow rate of the aeration device at each time point This represents the total airflow of the aeration device during the monitoring period.

6. The method for regulating and controlling the recycling of greywater according to claim 5, characterized in that: The bioreactor is a DMBR dual-membrane internal circulation bioreactor, which includes a biofilm reaction zone and a microfiltration zone. The greywater mixture forms an internal circulation in the biofilm reaction zone and the microfiltration zone through the action of aeration airflow. The biofilm reaction zone is equipped with a water distribution device, biofilm packing material, aeration device and air inlet electric valve. The microfiltration zone is equipped with an immersion microfiltration membrane module, aeration and flushing device and air inlet electric valve.

7. The method for regulating and controlling the recycling of greywater according to claim 6, characterized in that: The working process of the DMBR dual-membrane internal circulation bioreactor is as follows: The mixed wastewater is evenly introduced into the biofilm reaction zone through the water distribution device. The air inlet electric valve of the packing biofilm reaction zone is opened intermittently to alternately form an anaerobic-anoxic-aerobic environment, completing the aerobic nitrification phosphorus uptake, anoxic denitrification reaction, and anaerobic phosphorus release reaction of microorganisms. After the reaction, the mixed liquid of wastewater forms an internal circulation under the action of airflow. It flows through the microfiltration membrane filtration zone, where the detached biofilm and particulate matter are intercepted by the microfiltration membrane and returned to the biofilm reaction zone with the water flow. The clean water passes through the microfiltration membrane module and flows into the clean water pool.

8. A greywater recycling and regulation system, used to implement the regulation method according to any one of claims 1-7, characterized in that: It includes a pre-filtration unit, a greywater conditioning unit, a reactor assembly division unit, and an intelligent control unit; Pre-filtration unit: used to collect and pre-filter greywater; Greywater regulation unit: used to regulate the quantity and quality of greywater; Reactor set division unit: The operating status of multiple interconnected bioreactors is analyzed, and based on the analysis results, all bioreactors are divided into sets A, B and C respectively; Intelligent regulation unit: shuts down the bioreactor in set A, and after intelligently regulating the number of cycles and the amount of water treated in the bioreactor in set B, it combines the control commands of sets B and C to output control commands to the bioreactor. According to the control commands, the reclaimed water in the regulating tank is lifted to the bioreactor for treatment by a lift pump. The treated reclaimed water is then disinfected and kept on standby.

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