Sewage treatment process design method, sewage treatment system and control method

Abstract

The application provides a sewage treatment process design method, a sewage treatment system and a control method. The sewage treatment process design method is used to calculate the number of sludge screeners used in the sewage treatment process, and includes: obtaining the current organic matter proportion of sludge in the main sewage treatment route and the current water treatment capacity; determining a performance improvement target based on the current organic matter proportion and the current water treatment capacity; and calculating the number of sludge screeners used based on the corresponding calculation steps of the performance improvement target. The sewage treatment process design method, the sewage treatment system and the control method of the application provide a reasonable and effective calculation method for the number of sludge screeners used in the sewage treatment process. The determined number of sludge screeners used not only meets the actual needs of the main sewage treatment route, but also effectively controls the cost investment.

Description

Technical Field

[0001] This application relates to the field of wastewater treatment technology, and in particular to wastewater treatment process design methods, wastewater treatment systems and control methods. Background Technology

[0002] In wastewater treatment processes, sludge screeners are used for solid-liquid separation and sludge separation, which can improve wastewater treatment efficiency. However, in existing technologies, when sludge screeners need to be installed in wastewater treatment processes, the number of screeners is usually determined based on the experience of technicians, without an effective calculation method. When the treatment capacity of the sludge screeners does not match the treatment capacity of the wastewater, it can easily lead to problems such as excessive energy consumption, increased costs, and low treatment efficiency. Summary of the Invention

[0003] In view of this, the purpose of this application is to propose a wastewater treatment process design method, a wastewater treatment system and a control method to solve the above-mentioned technical problems.

[0004] A first aspect of this application provides a wastewater treatment process design method for calculating the number of sludge screeners used in a wastewater treatment process, comprising: obtaining the current organic matter ratio and current treated water volume of the sludge in the main wastewater treatment route; determining a performance improvement target based on the current organic matter ratio and the current treated water volume; and calculating the number of sludge screeners used based on the calculation steps corresponding to the performance improvement target.

[0005] Furthermore, the performance improvement target includes a first target, and the calculation steps corresponding to the first target include: based on the first target, determining the selection of the sludge screener, and obtaining the first specification parameters and initial underflow ratio of the selected sludge screener; obtaining the sewage treatment scale of the main sewage treatment route and the first target value corresponding to the first target, and determining the target operating cycle required to improve to the first target value; calculating a first target coefficient based on the initial underflow ratio, the target operating cycle and the first target value; and determining the number of sludge screeners to be used according to the sewage treatment scale, the first target coefficient and the first specification parameters.

[0006] Furthermore, the first target coefficient is calculated using the following formula:

[0007]

[0008] w2=X0·(1-n)·l·a·Q

[0009] w′2=X0·n·l·a·Q

[0010] Wherein, G1 is the first target value, T is the target operating cycle, a is the first target coefficient, w0 is the current organic sludge mass of the main wastewater treatment route, w1 is the daily increase in organic sludge mass in the main wastewater treatment route, w2 is the daily discharge of organic sludge from the main wastewater treatment route, w′0 is the current inorganic sludge mass of the main wastewater treatment route, w′1 is the daily increase in inorganic sludge mass in the main wastewater treatment route, w′2 is the daily discharge of inorganic sludge from the main wastewater treatment route; X0 is the external return sludge concentration of the main wastewater treatment route, n is the inorganic sludge proportion constant in the sludge discharged from the sludge screener, l is the initial underflow ratio, and Q is the wastewater treatment scale.

[0011] And / or, the daily increase in the mass of organic sludge in the main wastewater treatment route is calculated using the following formula:

[0012] w1=YQ0(S o -S e )-k d VfX

[0013] The daily increase in inorganic sludge in the main wastewater treatment route is calculated using the following formula:

[0014] w′1=Q0(T ss -T s )×50%

[0015] Where Y is the sludge production rate coefficient, Q0 is the design scale of the main wastewater treatment route, and S o BOD5, S of the influent to the main wastewater treatment line e The BOD5,k of the effluent from the main wastewater treatment line d Here, V is the endogenous metabolic coefficient, f is the volume of the biological treatment tank in the main wastewater treatment route, X is the current organic sludge percentage in the main wastewater treatment route, and T is the current sludge concentration in the main wastewater treatment route. ss T represents the SS concentration in the influent of the main wastewater treatment route. s The concentration of SS in the effluent from the main wastewater treatment route is given.

[0016] Further, determining the number of sludge screeners to be used based on the wastewater treatment scale, the first target coefficient, and the first specification parameters includes: calculating an initial number of sludge screeners based on the wastewater treatment scale, the first target coefficient, and the first specification parameters; determining the initial number as the final number of sludge screeners to be used in response to the calculated initial number being an integer; and determining the smallest integer greater than the initial number as the final number of sludge screeners to be used in response to the calculated initial number being a non-integer.

[0017] The initial number of sludge screeners is calculated using the following formula:

[0018]

[0019] S1 is the initial quantity, a is the first target coefficient, Q is the wastewater treatment scale, and M1 is the first specification parameter.

[0020] Furthermore, the performance improvement target includes a second target, and the calculation steps corresponding to the second target include: based on the second target, determining the selection of the sludge screener, and obtaining the second specification parameters and initial overflow ratio of the selected sludge screener; obtaining the second target value corresponding to the second target and the sludge discharge constant of the main wastewater treatment route; determining the second target coefficient based on the sludge discharge constant and the initial overflow ratio; and determining the number of sludge screeners to be used according to the second target coefficient, the second target value, and the second specification parameters.

[0021] Furthermore, the sludge screener selected for the same performance improvement objective can be one or more types.

[0022] A second aspect of this application provides a wastewater treatment system, including a main wastewater treatment route and a target number of sludge screeners. Each sludge screener includes an inlet on a side wall, a bottom outlet at the bottom, and an overflow outlet at the top. The main wastewater treatment route includes a biological treatment tank and a sedimentation tank. One side of the biological treatment tank is connected to an inlet pipeline, and the opposite side is connected to the sedimentation tank. The upper part of the sedimentation tank is connected to a drainage pipeline for discharging treated wastewater to the next stage, and the bottom is connected to the biological treatment tank via a sludge return pipeline. The target number of sludge screeners are arranged in parallel, and the inlet of each sludge screener is connected to the bottom of the sedimentation tank via a first sludge discharge pipeline, the overflow outlet is connected to the biological treatment tank via an overflow pipeline, and the bottom outlet is connected to an external sludge storage device via a second sludge discharge pipeline. The sludge screeners are used to screen the sludge discharged from the sedimentation tank and return the screened sludge to the biological treatment tank via the overflow pipeline. The target number is calculated according to a wastewater treatment process design method described in the first aspect.

[0023] A third aspect of this application provides another wastewater treatment system, including a main wastewater treatment route and a target number of sludge screens; each of the sludge screens includes an inlet disposed on a side wall, an underflow outlet disposed at the bottom, and an overflow outlet disposed at the top.

[0024] The main sewage treatment route includes a biological treatment tank and a sedimentation tank. One side of the biological treatment tank is connected to an inlet pipeline, and the opposite side is connected to the sedimentation tank.

[0025] The sedimentation tank is connected to a drainage pipeline at the top to discharge the treated wastewater to the next stage, and is connected to the biological treatment tank at the bottom through a sludge return pipeline.

[0026] The target number of sludge screens are arranged in parallel, and the inlet of each sludge screen is connected to the bottom of the sedimentation tank through a first sludge discharge pipeline, the overflow outlet is connected to an external sludge storage device through an overflow pipeline, and the bottom outlet is connected to the biological treatment tank through a second sludge discharge pipeline. The sludge screens are used to screen the sludge discharged from the sedimentation tank and return the screened sludge to the biological treatment tank through the second sludge discharge pipeline.

[0027] The target quantity is calculated according to the wastewater treatment process design method described in the first aspect.

[0028] A fourth aspect of this application provides a control method for a wastewater treatment system, applied to the wastewater treatment system described in the second aspect, wherein the performance improvement objective includes a first objective, and the control method includes:

[0029] Monitor the real-time organic sludge ratio in the biochemical tank;

[0030] In response to the real-time organic sludge ratio being less than a first threshold, the sludge return pipeline is shut down, and all the target number of sludge screens are turned on.

[0031] In response to the real-time organic sludge ratio being greater than or equal to the first threshold and less than the first target value corresponding to the first target, the sludge return pipeline is shut down, and a preset number of sludge screens are turned on.

[0032] In response to the real-time organic sludge ratio being greater than or equal to the first target value, the sludge return pipeline is opened, and all the target number of sludge screens are closed.

[0033] A fifth aspect of this application provides a control method for a wastewater treatment system, applied to the wastewater treatment system described in the third aspect, wherein the performance improvement objective includes a second objective, and the control method includes:

[0034] The target sludge volume index is determined based on the second target value corresponding to the second target.

[0035] Monitor the real-time sludge volume index in the biological treatment tank;

[0036] In response to the real-time sludge volume index being greater than a second threshold, the sludge return pipeline is shut off, and all the target number of sludge screens are controlled to operate at a first overflow ratio.

[0037] In response to the real-time sludge volume index being less than or equal to the second threshold and greater than the target sludge volume index, the sludge return pipeline is shut down, and all the target number of sludge screens are controlled to operate at the second overflow ratio.

[0038] In response to the actual sludge volume index being less than or equal to the target sludge volume index, the sludge return pipeline is opened, and all the target number of sludge screens are closed.

[0039] Wherein, the first overflow ratio is greater than the second overflow ratio.

[0040] As can be seen from the above, this application provides a wastewater treatment process design method, a wastewater treatment system, and a control method. First, the performance improvement target is determined based on the current organic matter content of the sludge in the main wastewater treatment route and the current treated water volume. Then, the number of sludge screeners to be used is calculated according to the calculation steps corresponding to the performance improvement target. This ensures that the number of sludge screeners used meets the actual needs of the main wastewater treatment route while effectively controlling cost input. Furthermore, the main wastewater treatment route is the main flow path of the wastewater to be treated. Whether designing a new wastewater treatment process for a wastewater treatment plant or modifying an existing process in situ, the performance improvement target is determined based on the current organic matter content of the sludge in the main wastewater treatment route and the current treated water volume. This ensures that the determination of the performance improvement target meets the actual needs of the wastewater treatment plant and is more reasonable. When adding sludge screeners to a wastewater treatment process, there may be multiple different purposes, such as increasing treatment capacity or improving treatment quality. Different purposes will have a certain impact on the number of sludge screeners. In this application, different calculation steps are designed for different performance improvement targets, so that the number of sludge screeners can be determined according to different performance improvement targets, making the calculation more reasonable. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of a wastewater treatment process design method in an embodiment of this application;

[0043] Figure 2 This is a schematic diagram of a wastewater treatment system according to an embodiment of this application;

[0044] Figure 3This is a schematic diagram of another wastewater treatment system in an embodiment of this application;

[0045] Figure 4 This is a flowchart of a control method for a wastewater treatment system according to an embodiment of this application;

[0046] Figure 5 A flowchart of another control method for a wastewater treatment system in an embodiment of this application;

[0047] Figure 6 This is a schematic diagram of an electronic device according to an embodiment of this application. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0049] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0050] The sludge screen 200 is a high-efficiency separation device that utilizes centrifugal force for solid-liquid separation, particle classification, and impurity removal. Its working principle involves high-speed rotation of the liquid, generating strong centrifugal force. This causes denser particles to be thrown against the outer wall and settle to the bottom outlet, while less dense liquid or particles are guided to the overflow outlet for discharge. The sludge screen 200 is mainly used for solid-liquid separation, particle classification, desludge and dewatering, concentration, and oil-water separation. It can also be used for liquid-liquid and gas-liquid separation. It features a simple structure, no moving parts, high efficiency in handling large flow rates of liquid, low operating costs, and convenient maintenance. Through reasonable adjustment of operating parameters, the sludge screen 200 can provide stable separation results, greatly improving separation efficiency and process accuracy, and has wide applications in industry.

[0051] In wastewater treatment, the sludge screen 200 can be used for solid-liquid separation after primary sedimentation tanks, sludge-water separation after secondary sedimentation tanks, and sludge sorting, improving treatment efficiency. It can be applied not only to urban sewage and industrial wastewater but also to oilfield wastewater for oil-water separation. The sludge screen 200 has advantages such as simple structure, small footprint, low operating cost, and convenient maintenance. However, its separation effect on fine particles is relatively poor, limiting its processing precision, and it requires regular maintenance to prevent clogging. By optimizing operating parameters, it can significantly improve wastewater treatment efficiency and promote resource reuse.

[0052] However, in existing technologies, when sludge screeners 200 need to be installed in wastewater treatment processes, the number of screeners 200 is usually determined solely by the experience of technicians, lacking an effective calculation method. Installing too many or too few sludge screeners 200 will negatively impact the wastewater treatment process. Too many screeners 200 increase equipment investment and operating costs, energy consumption, and maintenance and operating expenses, while also occupying more space, affecting the specific layout of the wastewater treatment plant. Too few screeners 200 result in insufficient treatment capacity, especially when the concentration of suspended solids in the water is high, leading to significantly reduced separation efficiency, unsatisfactory wastewater treatment results, excessive system load, increased risk of failure, and reduced operational stability. Only by using a reasonable number of sludge screeners 200 can optimal treatment effects and cost-effectiveness be achieved.

[0053] Furthermore, in actual operation, wastewater treatment plants often face insufficient treatment capacity and efficiency due to continuous population and urban expansion. Constructing new wastewater treatment plants is costly, difficult, and time-consuming, failing to effectively solve the current problems. Therefore, in-situ retrofitting of wastewater treatment plants has become a common approach. However, in-situ retrofitting requires consideration of many factors, such as limited land space, stability with the existing system, and investment and time costs. Utilizing sludge screeners 200 to retrofit existing wastewater treatment plants is an economically feasible method. Sludge screeners 200 have low land costs, are easy to operate, and are relatively simple to retrofit, enabling a rapid improvement in the treatment capacity and efficiency of wastewater treatment plants. However, the number of sludge screeners 200 needed for in-situ retrofitting is determined solely by the experience of technicians, without a readily available and effective calculation method.

[0054] In view of this, this application provides a wastewater treatment process design method, such as... Figure 1 As shown, the number of sludge screeners 200 used in the wastewater treatment process is calculated, including:

[0055] S101. Obtain the current organic matter content and current treated water volume of the sludge in the main wastewater treatment route 100;

[0056] S102. Determine the performance improvement target based on the current organic matter ratio and the current treated water volume;

[0057] S103. Calculate the number of sludge screeners 200 to be used based on the calculation steps corresponding to the performance improvement target.

[0058] In wastewater treatment processes, the organic matter content of sludge and the volume of water to be treated are key factors affecting treatment efficiency, capacity, and effluent quality. The organic matter content of sludge refers to the ratio between the mass of organic sludge and the total mass of sludge, which directly impacts the metabolic processes of microorganisms in the bioreactor, the settling properties of the sludge, and the sludge treatment methods. In the activated sludge process, organic matter is the primary energy source for microbial growth and metabolism. When the organic matter content in the sludge is high, the microorganisms in the bioreactor can obtain more energy to decompose organic pollutants, thus improving treatment efficiency. Conversely, low organic matter content indicates insufficient activity and quantity of microorganisms in the bioreactor, leading to reduced treatment efficiency. Furthermore, low organic matter content can cause uneven load distribution in the wastewater treatment system, resulting in system instability and even the death or decline of some microorganisms, further reducing treatment efficiency. Reduced microbial activity makes it difficult to completely degrade pollutants in the wastewater, leading to substandard effluent quality. Additionally, low organic matter content may result in insufficient nitrifying bacteria, affecting ammonia nitrogen conversion and causing poor ammonia nitrogen removal, thus increasing the ammonia nitrogen concentration in the effluent. When the volume of wastewater treated by the wastewater treatment plant increases, the hydraulic retention time in the bioreactor must be shortened, reducing the degradation time for microorganisms and potentially leading to incomplete organic matter degradation, thereby reducing treatment efficiency. Meanwhile, increased equipment load at the treatment plant leads to a decrease in dissolved oxygen concentration, which in turn affects the degradation effect of microorganisms. To ensure effluent quality, wastewater treatment plants need to expand their capacity or add treatment equipment to prevent overloading. Furthermore, with the increase in total water volume, the treatment system may face greater processing demands. If it fails to adapt to this increase, it may affect effluent quality, leading to higher BOD, COD, or suspended solids levels, and even impacting nitrogen and phosphorus removal efficiency. Therefore, increased water volume can result in problems such as low treatment efficiency, overload operation, and decreased effluent quality in the water treatment system.

[0059] In this application, the performance improvement target is first determined based on the current organic matter content of the sludge in the main wastewater treatment route 100 and the current treated water volume. Then, the required number of sludge screeners 200 is calculated according to the calculation steps corresponding to the performance improvement target. This ensures that the number of sludge screeners 200 meets actual needs while effectively controlling cost input. Furthermore, since the main wastewater treatment route 100 is the main flow route for the wastewater to be treated, whether designing a new wastewater treatment process for the wastewater treatment plant or modifying an existing process in situ, the performance improvement target is determined based on the current organic matter content of the sludge in the main wastewater treatment route 100 and the current treated water volume. This ensures that the performance improvement target meets the actual needs of the wastewater treatment plant and is more reasonable. When adding sludge screeners 200 to the wastewater treatment process, there may be multiple different purposes, such as increasing treatment capacity or improving treatment quality. Different purposes will affect the number of sludge screeners 200. In this application, different calculation steps are designed for different performance improvement targets, allowing the number of sludge screeners 200 to be determined according to different performance improvement targets, making the calculation more reasonable.

[0060] For example, when the main sewage treatment line 100 is modified in situ, the current organic matter content of the sludge and the current treated water volume can be determined by the actual average value over a period of time; when designing a new sewage treatment process for a sewage treatment plant, the organic matter content of the sludge and the treated water volume under stable operation of the main sewage treatment line 100 can be simulated based on the influent water quality and volume to be treated by the sewage treatment plant, and these can be used as the current organic matter content and the current treated water volume.

[0061] In some embodiments, the main wastewater treatment line 100 includes a biological treatment tank 110 and a sedimentation tank 120. One side of the biological treatment tank 110 is connected to an inlet pipe 130, and the other side is connected to the sedimentation tank 120. The upper part of the sedimentation tank 120 is connected to a drain pipe 140 for discharging the treated wastewater to the next stage, and the bottom is connected to the biological treatment tank 110 through a sludge return pipe 150.

[0062] Wastewater to be treated is introduced into the biological treatment tank 110 through the inlet pipeline 130. After the pollutants are decomposed in the biological treatment tank 110, the wastewater is introduced into the sedimentation tank 120 for sludge-water separation. The treated wastewater at the top of the sedimentation tank 120 is discharged to the next stage through the drainage pipeline 140, and the sludge at the bottom is returned to the biological treatment tank 110 through the sludge return pipeline 150. The biological treatment tank 110 is a biological treatment process based on the AO process, specifically including AAO (anaerobic-anoxic-aerobic), AO (anoxic-aerobic), or AOA (anoxic-aerobic-anoxic) processes. When the biological treatment tank 110 uses the AAO process, it sequentially includes an anaerobic tank, an anoxic tank, and an aerobic tank, achieving simultaneous nitrogen and phosphorus removal, suitable for stringent wastewater discharge requirements. In the anaerobic tank, polyphosphate-accumulating bacteria release phosphorus while absorbing soluble organic matter and storing it as an internal carbon source. In the anoxic tank, denitrifying bacteria reduce nitrates to nitrogen gas. In the aerobic tank, polyphosphate-accumulating bacteria absorb phosphorus and generate nitrates through nitrification, providing a nitrogen source for subsequent denitrification in the anoxic zone. When the biological treatment tank 110 uses the AO process, it includes an anoxic tank and an aerobic tank. In the anoxic tank, denitrifying bacteria use nitrates or nitrites as electron acceptors to reduce them to nitrogen gas, achieving denitrification. In the aerobic tank, aerobic microorganisms oxidize ammonia nitrogen in wastewater to nitrates (nitrification), providing nitrate nitrogen for denitrification. When the biological treatment tank 110 is an AOA process, the biological treatment tank 110 includes an anoxic tank, an aerobic tank and an anoxic tank in sequence. The anoxic tank located at the front position performs preliminary denitrification, converting some nitrates into nitrogen gas. The aerobic tank generates more nitrates through nitrification. The anoxic tank located at the back position further performs denitrification, reducing the concentration of the remaining nitrates.

[0063] In some embodiments, the performance improvement target includes a first target, and the calculation steps corresponding to the first target include: based on the first target, determining the selection of the sludge screener 200, and obtaining the first specification parameters and initial underflow ratio of the selected sludge screener 200; obtaining the sewage treatment scale of the sewage treatment main route 100 and the first target value corresponding to the first target, and determining the target operating cycle required to improve to the first target value; calculating a first target coefficient based on the initial underflow ratio, the target operating cycle and the first target value; and determining the number of sludge screeners 200 to be used according to the sewage treatment scale, the first target coefficient and the first specification parameters.

[0064] Specifically, the primary objective is to increase the proportion of organic matter in the sludge. As mentioned earlier, when the organic matter content of the sludge is too low, it can lead to insufficient microbial activity, low water treatment efficiency, and substandard effluent quality. It may even cause microbial stagnation or death, resulting in the stagnation or failure of the water treatment system. Therefore, when the proportion of organic matter in the main wastewater treatment route 100 is too low, the performance improvement target can be determined as increasing the proportion of organic matter in the sludge, i.e., the primary objective. Specifically, the organic matter proportion = MLVSS / MLSS, where MLVSS (Mixed Liquor Volatile Suspended Solids) represents the mass concentration of volatile suspended solids in the mixed liquor, mainly composed of organic matter (including active microorganisms and other organic matter); MLSS represents the mass concentration of total suspended solids in the mixed liquor, including organic components (such as microorganisms and organic matter) and inorganic components (such as silt and mineral particles).

[0065] Once the performance improvement target is determined to be increasing the proportion of organic matter in the sludge (i.e., the first target), the selection of the sludge screener 200 is determined based on this target, along with the corresponding first specification parameters and initial underflow ratio. Specifically, the sludge screener 200 includes a hydrocyclone, a device with an overflow outlet, an underflow outlet, and an inlet. Wastewater enters the hydrocyclone through the inlet and rotates at high speed inside. Larger materials settle and flow out through the underflow outlet, while lighter materials float and flow out through the overflow outlet. The first specification parameter is the design throughput of the sludge screener 200, and the underflow ratio of the sludge screener 200 = underflow rate / total feed rate. Different types of sludge screeners 200 have different treatment characteristics. Based on the first target and the characteristics of the wastewater treated by the main wastewater treatment route 100, a suitable sludge screener 200 is selected. Under the first target, the selectable specification parameter range for the sludge screener 200 can be up to 30m³ / h. 3 / h~200m 3 / h, specifically, can be 30m 3 / h, 40m 3 / h, 50m 3 / h、60m 3 / h、70m 3 / h、80m 3 / h、90m 3 / h、100m 3 / h、110m 3 / h, 120m 3 / h, 130m 3 / h, 140m 3 / h, 150m 3 / h, 160m 3 / h, 170m3 / h, 180m 3 / h、190m 3 / h、200m 3 The sludge screen 200 can be configured with specifications such as / h, or other specifications; there are no specific limitations. For example, a 50m³ sludge screen 200 can be selected. 3 When the sludge screen has a capacity of 200 per hour, the first specification parameter is 50m. 3 / h.

[0066] Obtain the wastewater treatment capacity of the main wastewater treatment route 100 (i.e., the wastewater treatment process requiring the installation of sludge screen 200). Whether constructing a new wastewater treatment route or retrofitting an existing process, the wastewater treatment capacity can be calculated after the main wastewater treatment route 100 is designed. This capacity represents the wastewater treatment volume or load capacity of the main wastewater treatment route 100. When retrofitting an existing process, the wastewater treatment capacity can be either the design capacity of the main wastewater treatment route 100 or the actual capacity determined based on historical treatment data; there are no specific restrictions. For newly constructed wastewater treatment processes, the designed capacity usually has a certain margin, slightly exceeding the actual treatment capacity required by the wastewater treatment plant, to ensure efficient treatment even with fluctuations in water quality and quantity. Therefore, when constructing a new wastewater treatment process, the wastewater treatment capacity can be either the design capacity calculated from the completed main wastewater treatment route 100 or the actual treatment capacity required by the wastewater treatment plant; there are no specific restrictions.

[0067] Based on the first objective, obtain the corresponding first target value and the target operating cycle required to increase it to the first target value. The first target value is the increased organic matter percentage, and the target operating cycle is the operating cycle required to increase the organic matter percentage in the existing sludge to the first target value. The optimal organic matter percentage of sludge varies between different wastewater treatment systems. For example, in conventional activated sludge processes, microorganisms are mainly used to degrade and purify organic matter in wastewater; organic matter is the main nutrient source for microorganisms, so the optimal organic matter percentage of sludge is usually high. In anaerobic treatment systems, anaerobic microorganisms are highly dependent on organic matter degradation, so the optimal organic matter percentage of sludge is also usually high. In biofilm processes, microorganisms adhere to the surface of the packing material; excessively high organic matter content may lead to an overly thick biofilm, increasing the risk of detachment and clogging, so the optimal organic matter percentage of sludge is slightly lower. Therefore, the first target value can be determined based on the actual conditions of the main wastewater treatment route 100. For example, when the current organic matter ratio of the sludge in the main sewage treatment route 100 is 0.4, the first target value can be determined to be 0.5, 0.6 or 0.7, etc., according to its actual situation, that is, to increase the organic matter ratio in the sludge from 0.4 to 0.5, 0.6 or 0.7, etc. Specifically, the first target value can be set to other values ​​according to the actual situation, and there is no specific limitation.

[0068] The first target coefficient is determined based on the first target value, the target operating cycle, and the initial underflow ratio. Finally, the number of sludge screeners 200 used is determined based on the wastewater treatment scale, the first target coefficient, and the first specification parameters. The number of sludge screeners 200 used is calculated based on the first target value and the target operating cycle. The calculation process fully considers the characteristics of sludge screeners 200 under different selections and the actual situation of the main wastewater treatment route 100 (such as the wastewater treatment scale), so that the final calculated number of sludge screeners 200 used can fully meet the requirements of the first target value, providing a specific and feasible calculation method for the number of sludge screeners 200 used.

[0069] In some embodiments, the first target coefficient is calculated using the following formula:

[0070]

[0071] w2=X0·(1-n)·l·a·Q

[0072] w′2=X0·n·l·a·Q

[0073] Wherein, G1 is the first target value, T is the target operating cycle, a is the first target coefficient, w0 is the current organic sludge mass of the main wastewater treatment route 100, w1 is the daily increase in organic sludge mass in the main wastewater treatment route 100, w2 is the daily discharge of organic sludge from the main wastewater treatment route 100, w0′ is the current inorganic sludge mass of the main wastewater treatment route 100, w1′ is the daily increase in inorganic sludge mass in the main wastewater treatment route 100, and w2′ is the daily discharge of inorganic sludge from the main wastewater treatment route 100; X0 is the external return sludge concentration of the main wastewater treatment route 100, n is the inorganic sludge proportion constant in the sludge discharged from the sludge screen 200, l is the initial underflow ratio, and Q is the wastewater treatment scale. The first target coefficient is the ratio of the total feed flow rate of the sludge screen 200 to the wastewater treatment scale, i.e., the first target coefficient = the total feed flow rate of the sludge screen 200 / the wastewater treatment scale. Therefore, after calculating the first target coefficient, the total feed flow rate of the sludge screener 200 can be obtained. Then, based on the total feed flow rate of the sludge screener 200, the number of sludge screeners 200 to be used can be calculated according to the wastewater treatment scale and the first specification parameters. The ratio of G1 to 1-G1 is the ratio of the proportion of organic matter to inorganic matter in the sludge after performance improvement. This ratio can be further converted into the ratio of the total mass of organic sludge to the total mass of inorganic sludge after performance improvement.

[0074] When the proportion of organic matter reaches the first target value, the total mass of organic sludge = the current organic sludge mass of the main sewage treatment route 100 + the daily increase in organic sludge mass × target operating cycle - the daily discharge of organic sludge mass × (target operating cycle - 1), and the total mass of inorganic sludge = the current inorganic sludge mass of the main sewage treatment route 100 + the daily increase in inorganic sludge mass × target operating cycle - the daily discharge of inorganic sludge mass × (target operating cycle - 1). The formula G1 / (1-G1) can then be derived.

[0075] After deriving the formula G1 / (1-G1), it is necessary to further calculate the daily discharge mass of inorganic sludge and organic sludge from the main wastewater treatment route 100. The daily discharge mass of organic and inorganic sludge from the main wastewater treatment route 100 may vary depending on water quality, quantity, and total sludge mass, but it can be estimated based on the wastewater treatment scale, the inorganic sludge proportion constant in the sludge discharged from the sludge screen 200, the initial underflow ratio, and the first target coefficient. Taking inorganic sludge mass as an example, after installing the sludge screen 200, all sludge is discharged through it. After determining the initial underflow ratio, the proportion of inorganic sludge in the underflow sludge discharged from the sludge screen 200 is usually a fixed coefficient, which can be determined through a limited number of experiments.

[0076] Therefore, we can further deduce that: the daily mass of inorganic sludge discharged = the concentration of sludge returned from the main wastewater treatment route 100 × the inorganic sludge proportion constant in the sludge discharged from the sludge screen 200 × the initial underflow ratio × the total feed flow rate of the sludge screen 200. Simultaneously, based on: the first target coefficient = the total feed flow rate of the sludge screen 200 / the wastewater treatment scale, we can further deduce that: the total feed flow rate of the sludge screen 200 = the first target coefficient × the wastewater treatment scale. Therefore, we can further deduce that: the daily mass of inorganic sludge discharged = the concentration of sludge returned from the main wastewater treatment route 100 × the inorganic sludge proportion constant in the sludge discharged from the sludge screen 200 × the initial underflow ratio × the first target coefficient × the wastewater treatment scale; thus, we can calculate the daily mass of inorganic sludge discharged from the main wastewater treatment route 100. Similarly, it can be deduced that the daily organic sludge mass discharged from the main wastewater treatment route 100 = the concentration of sludge returned from the main wastewater treatment route 100 × (1 - the inorganic sludge ratio constant in the sludge discharged from the sludge screen 200) × the initial underflow ratio × the first target coefficient × the wastewater treatment scale. The final first target coefficient can then be calculated.

[0077] The external return sludge concentration of the main wastewater treatment route 100 refers to the concentration of sludge returned from sedimentation tank 120 (or secondary sedimentation tank) to the biological treatment unit (such as biochemical tank 110), i.e., the sludge concentration in the sludge return pipeline 150. During in-situ modification, the current organic sludge mass, current inorganic sludge mass, daily increase in organic sludge mass, daily increase in inorganic sludge mass, and external return sludge concentration of the main wastewater treatment route 100 can all be calculated or directly obtained based on the actual conditions of the main wastewater treatment route 100. Optionally, it can be an average value over a certain period, with no specific restrictions. When designing a new wastewater treatment process for a wastewater treatment plant, after the main wastewater treatment route 100 is designed, the current organic sludge mass, current inorganic sludge mass, daily increase in organic sludge mass, daily increase in inorganic sludge mass, and external return sludge concentration can be calculated based on the actual conditions of the wastewater being treated by the wastewater treatment plant. Alternatively, these values ​​can be obtained through simulation using a wastewater treatment simulator. A wastewater treatment simulator is a computer software tool used to simulate and optimize wastewater treatment processes. By simulating different wastewater treatment technologies, operating conditions, and equipment performance, it helps engineers, operators, and researchers improve the efficiency, stability, and sustainability of wastewater treatment systems. It can provide scientific basis and optimization solutions for the design, operation, renovation, and maintenance of wastewater treatment plants. Therefore, after determining the main wastewater treatment route 100, a wastewater treatment simulator can be used to simulate the main wastewater treatment route 100 under normal operating conditions. It can simulate the current organic sludge mass, current inorganic sludge mass, daily increase in organic sludge mass, daily increase in inorganic sludge mass, and external return sludge concentration of the main wastewater treatment route 100 during normal operation.

[0078] Specifically, the target operating cycle can be 20 days, or it can be 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 28, 30 days, or any other number of days. The specific number of days can be set according to the actual situation of the wastewater treatment plant, and there are no restrictions. The initial underflow ratio is 5%, but it can also be 1%, 2%, 3%, 4%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 15%. The percentages can be 1%, 16%, 18%, 20%, etc., or other ratios, which can be determined based on the specific conditions of the sludge screener 200 and the wastewater treatment plant. There are no specific restrictions. The inorganic sludge ratio constant in the sludge discharged from the sludge screener 200 is 0.4 to 0.8, specifically 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, etc., or other values ​​less than 0.4 or greater than 0.8. These can be further determined based on the scale and specific parameters of the sludge screener 200. There are no specific restrictions.

[0079] In some embodiments, the daily increase in organic sludge mass in the main wastewater treatment route 100 is calculated using the following formula: w1 = YQ0(S o -S e )-k d VfX.

[0080] Where Y is the sludge production rate coefficient, Q0 is the design scale of the main sewage treatment route 100, and S o The BOD5,S of the influent to the main wastewater treatment line 100 e The BOD5,k of the effluent from the main wastewater treatment line 100 d V is the endogenous metabolic coefficient, V is the volume of the biochemical tank of the main wastewater treatment route 100, f is the current organic sludge ratio of the main wastewater treatment route 100, and X is the current sludge concentration of the main wastewater treatment route 100.

[0081] Inorganic sludge is contributed by the influent SS (suspended solids). In some embodiments, the daily increase in the mass of inorganic sludge in the main wastewater treatment line 100 is calculated using the following formula:

[0082] w1′=Q0(T ss -T s )×50%

[0083] Among them, T ss The concentration of SS in the influent of the main wastewater treatment route 100 is T. s The concentration of SS in the effluent from the main wastewater treatment route 100 is given.

[0084] Biological treatment tank volume refers to the effective volume within a biological treatment unit (such as activated sludge tanks, anaerobic tanks, and aerobic tanks) capable of holding wastewater and supplying it to microorganisms for degrading organic matter and removing pollutants. The design of this volume is closely related to factors such as treatment capacity, wastewater quality and quantity, and microbial growth. The sludge yield coefficient is an important parameter for measuring the efficiency of converting organic matter in wastewater into sludge during wastewater treatment. It typically represents the amount of sludge produced per unit of organic matter degradation, expressed in g / Mg BOD5 or g / COD, i.e., the mass of sludge produced for each certain amount of chemical oxygen demand (COD) or biochemical oxygen demand (BOD) degraded. The value of the sludge yield coefficient may vary depending on the wastewater treatment process and conditions. For example, for aerobic treatment (such as the activated sludge process), the sludge yield coefficient is typically 0.3-0.8 g sludge / g BOD5; for anaerobic treatment, the sludge yield coefficient is usually lower, typically 0.1-0.4 g sludge / g COD. The value of the sludge yield coefficient can be determined according to the actual situation, and there is no specific restriction. BOD5 (Biochemical Oxygen Demand over 5 days) refers to the amount of oxygen required by microorganisms in a water sample to decompose organic matter within 5 days at a temperature of 25°C. It is an important indicator of the amount of oxygen consumed by microorganisms in water bodies when decomposing organic matter, and is usually used to measure the concentration of organic pollutants in water bodies and their biodegradation potential.

[0085] The endogenous metabolic coefficient represents the amount of organic matter consumed by a unit mass of activated sludge (or microorganisms) through endogenous metabolism per unit time. In short, endogenous metabolism is the process by which microorganisms consume organic matter in sludge through their own biological metabolic activities when there is a lack of exogenous organic matter. The endogenous metabolic coefficient mainly describes the rate at which microorganisms consume organic matter in sludge through endogenous metabolism during wastewater treatment when there is no supply of exogenous organic matter. It reflects the ability of microorganisms to maintain growth and metabolism solely through their own metabolic activities in the absence of external organic matter sources (such as pollutants in the influent). The specific range of the endogenous metabolic coefficient is affected by several factors, such as the type of microorganism, wastewater quality, operating conditions (such as temperature, pH, dissolved oxygen, etc.), and sludge age. It is typically between 0.02 and 0.10 g sludge / g·d; under specific conditions, the endogenous metabolic coefficient may be higher, especially in high sludge age operations, potentially reaching 0.1 to 0.3 g sludge / g·d. The specific value of the endogenous metabolic coefficient can be determined based on actual circumstances and is not subject to any particular limitation.

[0086] X represents the current sludge concentration of the main wastewater treatment route 100. Specifically, it can be the sludge concentration of the aerobic tank. The growth and reproduction of the microbial community in the aerobic tank directly determines the sludge concentration, so the sludge concentration of the aerobic tank can be used as the current sludge concentration of the main wastewater treatment route 100.

[0087] In some embodiments, determining the number of sludge screeners 200 to be used based on the wastewater treatment scale, the first target coefficient, and the first specification parameters includes:

[0088] The initial number of sludge screeners 200 is calculated based on the wastewater treatment scale, the first target coefficient, and the first specification parameters; in response to the calculated initial number being an integer, the initial number is determined to be the final number of sludge screeners 200 used; in response to the calculated initial number being a non-integer, the smallest integer greater than the initial number is determined to be the final number of sludge screeners 200 used.

[0089] The initial quantity calculated based on the wastewater treatment scale, the first target coefficient, and the first specification parameters may be an integer or a non-integer. When the initial quantity is an integer, it can be determined as the final number of sludge screeners 200 used. When the initial quantity is a non-integer, the smallest integer greater than the initial quantity can be determined as the final number of sludge screeners 200 used. For example, if the calculated initial quantity is 1.8, the final number of sludge screeners 200 used can be determined to be 2; if the calculated initial quantity is 3, the final number of sludge screeners 200 used can be determined to be 3.

[0090] In some embodiments, the initial number of sludge screeners 200 is calculated using the following formula:

[0091]

[0092] S1 represents the initial quantity, a represents the first target coefficient, Q represents the wastewater treatment scale, and M1 represents the first specification parameter. When all selected sludge screeners 200 are of the same model, this formula can be used to calculate the required quantity of sludge screeners 200. When multiple models of sludge screeners 200 are selected, the total feed flow rate that the sludge screeners 200 need to process can be calculated first, and then the specific quantity used can be determined according to the model of the sludge screeners 200. For example, with a = 20% and Q = 416.7... 3 Taking / h as an example, the total feed flow rate that the sludge screen 200 needs to handle is calculated to be 83.34. 3 / h, when using 20m 3 / h and 30m 3When the sludge screening unit has a capacity of 200 units per hour, the required quantity is determined to be three 20m³ units. 3 200 sludge screens and 1 30m sludge screen per hour 3 A 200 / h sludge screen can also be configured as two 20m screens. 3 200 sludge screens and two 30m³ / h sludge screens 3 A 200 / h sludge screen can also be a 20m unit. 3 200 sludge screens and 3 x 30m³ screens per hour 3 A 200 m³ / h sludge screen can also be used entirely with 20 m³ / h screens. 3 A sludge screening unit of 200 per hour, i.e., five 20m units. 3 A 200 m³ / h sludge screen can also be used entirely with 30 m³ screens. 3 A sludge screening unit of 200 m³ / h is used, which means three 30 m³ screens are selected. 3 The sludge screening capacity is 200 units per hour, with no specific limit.

[0093] In some embodiments, the performance improvement target includes a second target, and the calculation steps corresponding to the second target include: determining the selection of the sludge screener 200 based on the second target, and obtaining the second specification parameters and initial overflow ratio of the selected sludge screener 200; obtaining the second target value corresponding to the second target and the sludge discharge constant of the wastewater treatment main route 100; determining the second target coefficient based on the sludge discharge constant and the initial overflow ratio; and determining the number of sludge screeners 200 to be used according to the second target coefficient, the second target value, and the second specification parameters.

[0094] Specifically, the second objective is to increase the total wastewater treatment capacity, and the second target value is the increased total wastewater treatment capacity. When designing a wastewater treatment plant, the design capacity of the wastewater treatment process is determined based on a comprehensive set of factors, including expected wastewater flow, expected wastewater quality, regulations and discharge requirements, future growth and expansion needs, treatment processes, and economic costs. However, in actual operation, factors such as urbanization, industrialization, and fluctuations in water quality and quantity may deviate from the initial estimates, resulting in the designed capacity failing to meet actual demand. Therefore, in-situ modifications to the wastewater treatment plant are necessary to increase the capacity of the original wastewater treatment process. During the design process, given the typically limited area of ​​a wastewater treatment plant, it is essential to ensure adequate space for equipment installation while also preserving operating space for workers and transportation equipment. Furthermore, considering economic investment and cost, the overall wastewater treatment capacity can be increased by installing a sludge screen 200. After the main sewage treatment route 100 is designed, the number of sludge screeners 200 to be used is determined by further calculation. Then, by installing the corresponding number of sludge screeners 200, the total sewage treatment capacity can be increased without extending the treatment time or process of the main route, which can effectively reduce the land area and economic investment.

[0095] When the organic matter content in activated sludge is too high, microorganisms cannot degrade all organic matter in time, reducing treatment efficiency. More time is needed to decompose organic matter, necessitating an increase in hydraulic retention time, which significantly reduces the wastewater treatment capacity per unit time, failing to meet the actual needs of the wastewater treatment plant. Simultaneously, excessive organic matter content leads to microbial overgrowth, causing sludge bulking and further reducing treatment efficiency. Furthermore, the decomposition of organic matter by microorganisms produces more cells and metabolic products, increasing sludge production, disposal costs, and operational burden. An excessively high organic matter content can also overload microorganisms, preventing complete degradation of organic matter in the water and resulting in substandard effluent quality.

[0096] Therefore, when the current treatment volume of the main wastewater treatment line 100 is too high or the current organic matter content in the sludge is too high, the performance improvement target can be determined as increasing the total wastewater treatment volume, i.e., the first target, which is to improve the load capacity of the main wastewater treatment line 100 by installing a sludge screener 200.

[0097] When the second objective is to increase the total wastewater treatment capacity, a suitable sludge screener 200 is selected based on this objective, and the corresponding second specification parameters and initial overflow ratio are obtained. Specifically, the second specification parameter is the design capacity of the sludge screener 200, and the overflow ratio of the sludge screener 200 = overflow flow rate / total feed flow rate. Under the second objective, the selectable specification parameter range for the sludge screener 200 can be 2.5m. 3 / h~50m 3 / h, specifically 2.5m 3 / h、3m 3 / h, 3.5m 3 / h、4m 3 / h, 4.5m 3 / h、5m 3 / h、7m 3 / h, 10m 3 / h, 15m 3 / h、18m 3 / h, 20m 3 / h、22m 3 / h, 25m 3 / h、26m 3 / h、28m 3 / h、29m 3 / h, 30m 3 / h、32m 3 / h, 35m 3 / h, 38m 3 / h, 40m 3 / h、42m 3 / h, 45m 3 / h、48m 3 / h, 50m 3 The sludge screen 200 can be configured with specifications such as / h, or other specifications; there are no specific limitations. For example, a 7.5m sludge screen 200 can be selected. 3 For a sludge screener with a capacity of 200 m / h, the second specification parameter for selection is 7.5 m. 3 / h. Then, based on the second objective, determine the second objective value, which is the total amount of wastewater treated after the upgrade. The second objective value can be determined based on the design scale of the main wastewater treatment route 100, for example, it can be 1.5, 1.8, 2, 2.1, 2.2, 2.5, or 3 times the design scale, or it can be other values, which can be determined according to the specific situation of the wastewater treatment plant, without any specific restrictions.

[0098] To further obtain the sludge discharge constant of the main wastewater treatment route 100, the sludge discharge constant = sludge discharge flow rate / total wastewater treatment volume, can be obtained through a limited number of experiments. During wastewater treatment, if microorganisms remain in the system for too long, their activity will decrease. If they are not discharged from the system in a timely manner, it will lead to problems such as a decrease in the ability to decompose organic matter, thereby reducing treatment efficiency. Simultaneously, excessive sludge accumulation in the system may lead to sludge bulking, i.e., changes in sludge settling properties, affecting solid-liquid separation efficiency. Therefore, after a period of operation, the wastewater treatment system needs to discharge sludge to maintain microbial activity, prevent sludge aging, maintain a reasonable sludge concentration and age, avoid sludge bulking, and improve effluent quality. The sludge discharge flow rate of the wastewater treatment system is usually somewhat correlated with the total wastewater treatment volume of the system. For example, in the activated sludge process, regular sludge removal is necessary to maintain appropriate sludge concentration and age. It is estimated that the oven-dry sludge production of a 10,000-ton water plant is approximately 0.01–0.05%. When the wastewater treatment process is relatively fixed, the concentration of discharged sludge remains within a certain range. The residual sludge concentration in the activated sludge process is approximately stable at around 10,000 mg / L (99% moisture content). Therefore, the sludge removal constant can be determined to be 1%–5%. The sludge removal constant varies depending on the specific biological treatment process. Furthermore, the sludge removal constant is also related to the influent water quality. When the organic matter concentration is high, microbial reproduction is rapid, and the sludge removal constant can be appropriately increased to control the sludge concentration. Conversely, when the suspended solids content increases, the sludge volume increases, and the sludge removal constant can also be appropriately increased to prevent sludge accumulation. Therefore, the sludge discharge constant can be determined based on the specific conditions such as the process type and influent water quality of the main sewage treatment route 100. For example, it can be 1% to 5%, specifically, it can be 0.5%, 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.8%, 3%, 3.2%, 3.5%, 3.6%, 3.8%, 4%, 4.2%, 4.5%, 4.6%, 4.8%, 5%, etc., or other values ​​within 1% to 5%, or other values ​​less than 1% or greater than 5%, without any specific limitation.

[0099] The second target coefficient can be determined based on the sludge discharge constant and the initial overflow ratio. Specifically, the second target coefficient can be calculated using the following formula: Second target coefficient = Sludge discharge constant / Initial overflow ratio.

[0100] Under the second objective, after the sludge screener 200 is installed on the main wastewater treatment route 100, all sludge discharge is carried out through the overflow of the sludge screener 200, i.e., the mass of discharged sludge = the discharge volume of the overflow outlet. The discharge volume of the overflow outlet = initial overflow ratio × total feed flow rate of the sludge screener 200 = sludge discharge constant × total wastewater treatment volume. Therefore, the total feed flow rate of the sludge screener 200 = (sludge discharge constant × total wastewater treatment volume) / initial overflow ratio = second objective coefficient × total wastewater treatment volume. Specifically, the initial overflow ratio can be 10%, or 5%, 6%, 7%, 8%, 9%, 11%, 12%, 15%, 16%, 18%, 20%, 22%, 25%, 26%, 30%, etc., or other ratios. It can be determined based on the specific conditions of the sludge screener 200 and the wastewater treatment plant, and there are no specific restrictions.

[0101] Once the second target coefficient is determined, the required number of sludge screeners 200 can be calculated based on the second target coefficient, the second target value, and the second specification parameters. This determines the required number of sludge screeners 200 to be installed on the main wastewater treatment route 100 when the performance improvement target is to increase the total wastewater treatment capacity.

[0102] In some embodiments, the sludge screener 200 selected for the same performance improvement objective can be one or more types. Depending on the treatment characteristics of the main wastewater treatment route 100 and the characteristics of different types of sludge screeners 200, multiple types of sludge screeners 200 can be used in combination. That is, under the first objective or the second objective, all sludge screeners 200 can be of the same type, or multiple types, such as 2, 3, or 4 types, etc., used in combination, without any specific limitation.

[0103] In some embodiments, determining the number of sludge screeners 200 to be used based on the second target coefficient, the second target value, and the second specification parameters includes: calculating an initial number of sludge screeners 200 based on the second target coefficient, the second target value, and the second specification parameters; determining the initial number as the final number of sludge screeners 200 to be used in response to the calculated initial number being an integer; and determining the smallest integer greater than the initial number as the final number of sludge screeners 200 to be used in response to the calculated initial number being a non-integer.

[0104] The initial quantity calculated based on the second target coefficient, the second target value, and the second specification parameters may be an integer or a non-integer. When the initial quantity is an integer, it can be determined as the final number of sludge screeners 200 used. When the initial quantity is a non-integer, the smallest integer greater than the initial quantity can be determined as the final number of sludge screeners 200 used. For example, if the calculated initial quantity is 5.5, the final number of sludge screeners 200 used can be determined to be 6; if the calculated initial quantity is 6, the final number of sludge screeners 200 used can be determined to be 6.

[0105] In some embodiments, the initial number of sludge screeners 200 is calculated according to the following formula:

[0106]

[0107] S1 is the initial quantity, b is the second target coefficient, G2 is the second target value, and M2 is the second specification parameter.

[0108] In some embodiments, the method further includes: calculating the runtime of the sludge screener 200 based on the number of times the sludge screener 200 is used.

[0109] When performance improvement is the primary objective, the daily operating time of the sludge screen 200 is calculated based on the initial underflow ratio, the first specification parameter, the number of sludge screens 200 used, and the daily sludge discharge volume of the main wastewater treatment route 100. Specifically, the daily operating time of the sludge screen 200 = daily sludge discharge volume of the main wastewater treatment route 100 / (number of sludge screens 200 used × initial underflow ratio × first specification parameter). For example, the daily sludge discharge volume of the main wastewater treatment route 100 is 74.666 m³. 3 (Wet sludge with a moisture content of 98.5% and a density of 1), the first specification parameter is 50m³. 3 With a capacity of 2 per hour and an initial underflow ratio of 5%, the daily operating time of sludge screener 200 is 74.666 / (50×5%×2)=14.9h. That is, each of the two sludge screeners 200 needs to run for 14.9h per day to complete the corresponding sludge discharge requirements.

[0110] When the performance improvement target is the second objective, the daily operating time of the sludge screener 200 is calculated based on the initial overflow ratio, the first specification parameter, the number of sludge screeners 200 used, and the daily sludge discharge volume of the main wastewater treatment route 100. Specifically, the daily operating time of the sludge screener 200 = daily sludge discharge volume of the main wastewater treatment route 100 / (number of sludge screeners 200 used × initial overflow ratio × first specification parameter). For example, the daily sludge discharge volume of the main wastewater treatment route 100 is 74.666 m³. 3 (Wet sludge with a moisture content of 98.5% and a density of 1), the second specification parameter is 7.5m. 3 With a capacity of 6 units and an initial overflow ratio of 20%, the daily operating time of sludge screener 200 is 74.666 / (7.5×20%×6) = 8.3h. This means that each of the 6 sludge screeners 200 needs to run for 8.3h per day to meet the corresponding sludge discharge requirements.

[0111] The technical solution of this application will be further explained below through specific embodiments.

[0112] (1) Example 1

[0113] A wastewater treatment plant's Route A uses an AAO process, currently suffering from several problems including unstable effluent quality and low treatment efficiency, necessitating in-situ modification. Route A was modified as the main wastewater treatment route 100. Data on the organic matter content of the sludge and the treated water volume of Route A over the past month were obtained. The results confirmed that the main problem with Route A was the low organic matter content in the sludge, leading to low microbial activity and consequently unstable effluent quality and low treatment efficiency. Therefore, the modification target, or performance improvement target, was determined to be increasing the organic matter content in the sludge.

[0114] Based on the characteristics of the wastewater to be treated by Route A and the performance improvement goals, the first specification parameter is determined to be 50m. 3 The sludge screener 200 is set at / h, and the initial underflow ratio of the sludge screener 200 is determined to be 5%. The current organic matter ratio of Route A is 0.4, and the first target value is determined to be 0.6. The target operating cycle is 20 days, that is, the target operating cycle T required to increase the organic matter ratio from 0.4 to 0.6 is 20 days.

[0115] Based on historical treatment data from Route A, the current organic sludge mass, current inorganic sludge mass, daily increase in organic sludge mass, daily increase in inorganic sludge mass, and external return sludge concentration of the main wastewater treatment route 100 are determined as follows: 6400 kg, 9600 kg, 520 kg, 600 kg, and 10 kg / m³, respectively. The wastewater treatment capacity of Route A can be either its design capacity or the actual capacity determined based on historical treatment data. In this embodiment, the design capacity of Route A, i.e., 10000 m³, is used as the wastewater treatment capacity. 3 / d. Based on the first specification parameters of sludge screener 200, the initial underflow ratio, and the characteristics of the wastewater, the inorganic sludge ratio constant in the sludge discharged from sludge screener 200 is determined to be 0.7.

[0116] After installing the sludge screen 200, all sludge discharge from Route A is completed through the sludge screen 200. The calculated daily organic sludge mass discharged from the main wastewater treatment route 100 (i.e., the daily organic sludge mass that needs to be discharged by the sludge screen 200) is: 10 kg / m³. 3 ×(1-0.7)×5%×a×10000m 3 / d=1500a.

[0117] The calculated daily inorganic sludge mass discharged from the main wastewater treatment line 100 (i.e., the daily inorganic sludge mass required to be discharged by sludge screener 200) is: 10 kg / m³. 3 ×0.7×5%×a×10000m 3 / d=3500a.

[0118] Calculate the first target coefficient a: 0.6 / 0.4=(6400+520X20-1500aX(20-1)) / (9600+600X20-3500aX(20-1))=(16800-28500a) / (21600-66500a), and get a=21.89%.

[0119] Wastewater treatment capacity is 10,000 m³ 3 / d, converted to m 3 / h is the unit, which is 416.7m. 3 / h; Calculate the initial number of sludge screeners 200: 21.89% × 416.7m 3 / h÷50m 3 / h = 1.8. The final number of sludge screeners 200 used is determined to be 2. After connecting the two sludge screeners 200 to route A, sludge is discharged from the system through the underflow outlet. The sludge is then screened by the sludge screeners 200, allowing more inorganic sludge to be discharged from the underflow outlet to the outside of the system. This significantly increases the proportion of organic sludge in route A.

[0120] Keeping other data constant, when T is 10 days, the corresponding first target coefficient a is 46.22%, the initial number of sludge screeners 200 is 3.85, and the final number used is 4; when T is 30 days, the corresponding first target coefficient a is 14.34%, the initial number of sludge screeners 200 is 1.2, and the final number used is 2.

[0121] (2) Example 2

[0122] A wastewater treatment plant's B route uses an AO process and currently suffers from several problems, including low treatment efficiency and poor effluent quality, requiring in-situ modification. The B route was modified as the main wastewater treatment route 100. Data on the organic matter content of the sludge and the treated water volume of the B route over the past month were obtained. This confirmed that the main problem with the B route is that the actual treated water volume is far higher than the initial design capacity, leading to unstable effluent quality and low treatment efficiency. Therefore, the modification target, i.e., the performance improvement target, was determined to be increasing the total wastewater treatment capacity.

[0123] Historical data shows that Route B was designed to have a scale of 10,000 meters. 3 / d, which is 416.7m 3 / h; Based on the actual needs of Route B, an excess of 50% over the design scale is required to meet the actual demand. Therefore, the second target value is determined to be: 50% × 416.7m 3 / h+416.7m 3 / h=625.05m 3 / h.

[0124] Based on the characteristics of the wastewater to be treated by Route B and the performance improvement goals, the second specification parameter of 7.5m was selected. 3 The sludge screen 200 has a flow rate of / h, and the initial overflow ratio of the sludge screen 200 is determined to be 10%. Based on historical data from Route B, the sludge discharge constant for this route is 2%.

[0125] Calculate the second target coefficient b: 2% ÷ 10% = 20%.

[0126] Calculate the initial quantity S1 of sludge screen 200: 20% × 625.05m 3 / h÷7.5m 3 / h = 16.7.

[0127] The final number of sludge screeners 200 used was determined to be 17.

[0128] After connecting and operating 17 sludge screeners 200 to Route B, sludge is discharged from the system through the overflow outlet. The sludge is then screened by the sludge screeners 200, and more flocculents with poor settling performance and low density are discharged from the overflow outlet to the outside of the system. Sludge with good settling performance and high density returns to the system to participate in the reaction. The effluent quality and quantity of Route B are stable, effectively increasing the total amount of sewage treated by Route B and improving the sewage load capacity of the route.

[0129] Based on the same inventive concept, this application also provides a wastewater treatment system, such as... Figure 2 As shown, it includes a main wastewater treatment route 100 and a target number of sludge screens 200; each of the sludge screens 200 includes an inlet disposed on the side wall, an underflow outlet disposed at the bottom and an overflow outlet disposed at the top.

[0130] The main sewage treatment line 100 includes a biological treatment tank 110 and a sedimentation tank 120. One side of the biological treatment tank 110 is connected to an inlet pipeline 130, and the other side is connected to the sedimentation tank 120.

[0131] The sedimentation tank 120 is connected to a drainage pipeline 140 at the top to discharge the treated wastewater to the next stage, and is connected to the biological tank 110 at the bottom through a sludge return pipeline 150.

[0132] The target number of sludge screeners 200 are arranged in parallel, and the inlet of each sludge screener 200 is connected to the bottom of the sedimentation tank 120 through the first sludge discharge pipeline 300, the overflow port is connected to the biological treatment tank 110 through the overflow pipeline 400, and the bottom outlet is connected to an external sludge storage device through the second sludge discharge pipeline 500. The sludge screener 200 is used to screen the sludge discharged from the sedimentation tank 120 and return the screened sludge to the biological treatment tank 110 through the overflow pipeline 400.

[0133] The target quantity is calculated according to a wastewater treatment process design method described in any of the foregoing embodiments.

[0134] When it is necessary to install sludge screeners 200 on the existing or preliminarily designed wastewater treatment main route 100, the number of sludge screeners 200 to be used, i.e. the target number, is first calculated using the aforementioned wastewater treatment process design method. Then, the target number of sludge screeners 200 are installed in parallel on the side flow of the wastewater treatment main route 100 to obtain the final wastewater treatment system. When the performance improvement target of the main sewage treatment route 100 is the primary objective, sludge is discharged through the underflow outlet of the sludge screen 200, and the overflow outlet is used for backflow. Specifically, the overflow outlet is connected to the biological treatment tank 110 through the overflow pipeline 400, and the underflow outlet is connected to the external sludge storage device through the second sludge discharge pipeline 500. The sludge from the sedimentation tank 120 enters the sludge screen 200 through the first sludge discharge pipeline 300 and the inlet. In the sludge screen 200, it rotates at high speed, and then, under the action of centrifugal force, the heavier inorganic matter settles down and moves towards the underflow outlet, and is eventually discharged to the outside of the system; the lighter organic matter rises and moves towards the overflow outlet, and is eventually returned to the biological treatment tank 110 through the overflow outlet and the overflow pipeline 400 to continue participating in sewage treatment, thereby increasing the organic matter ratio of the sludge in the biological treatment tank 110. In this wastewater treatment system, the sludge screen 200 is installed on the side flow of the main wastewater treatment route 100. The sludge screen 200 occupies a small area, thus effectively utilizing the area of ​​the wastewater treatment plant. At the same time, the target quantity is calculated based on the performance improvement target to be achieved by the main wastewater treatment route 100. This ensures that after the sludge screen 200 is installed, it can effectively achieve the corresponding performance improvement target, namely, effectively increase the proportion of organic matter in the sludge of the main wastewater treatment route 100, thereby effectively improving the treatment capacity, treatment efficiency, and effluent quality of the wastewater treatment plant.

[0135] Based on the same inventive concept, this application also provides another wastewater treatment system, such as Figure 3 As shown, it includes a main wastewater treatment route 100 and a target number of sludge screens 200; each of the sludge screens 200 includes an inlet disposed on the side wall, an underflow outlet disposed at the bottom and an overflow outlet disposed at the top.

[0136] The main sewage treatment line 100 includes a biological treatment tank 110 and a sedimentation tank 120. One side of the biological treatment tank 110 is connected to an inlet pipeline 130, and the other side is connected to the sedimentation tank 120.

[0137] The sedimentation tank 120 is connected to a drainage pipeline 140 at the top to discharge the treated wastewater to the next stage, and is connected to the biological tank 110 at the bottom through a sludge return pipeline 150.

[0138] The target number of sludge screeners 200 are arranged in parallel, and the inlet of each sludge screener 200 is connected to the bottom of the sedimentation tank 120 through the first sludge discharge pipeline 300, the overflow port is connected to an external sludge storage device through the overflow pipeline 400, and the bottom outlet is connected to the biological treatment tank 110 through the second sludge discharge pipeline 500. The sludge screener 200 is used to screen the sludge discharged from the sedimentation tank 120 and return the screened sludge to the biological treatment tank 110 through the second sludge discharge pipeline 500.

[0139] The target quantity is calculated according to a wastewater treatment process design method described in any of the foregoing embodiments.

[0140] When the performance improvement target of the main wastewater treatment line 100 is the second target, sludge is discharged through the overflow port of the sludge screen 200, and the underflow port achieves backflow. That is, the overflow port is connected to the external sludge storage device through the overflow pipeline 400, and the underflow port is connected to the biological treatment tank 110 through the second sludge discharge pipeline 500. The sludge from the sedimentation tank 120 enters the sludge screen 200 through the first sludge discharge pipeline 300 and the inlet. In the sludge screen 200, it rotates at high speed, and then under the action of centrifugal force... Flocculent sludge with poor settling properties rises and moves towards the overflow outlet, eventually being discharged from the system via the overflow outlet and overflow pipeline 400. Sludge with better settling properties, being heavier, moves towards the underflow outlet and is eventually returned to the biological treatment tank 110 via the underflow outlet and the second sludge discharge pipeline 500 to continue participating in the reaction, thereby improving the sludge settling properties of the biological treatment tank 110. When the sludge settling properties are good, the sludge-water separation time is effectively shortened, allowing more wastewater to be treated per unit time, thus increasing the total wastewater treatment capacity. In this wastewater treatment system, the sludge screen 200 is installed on the side flow of the main wastewater treatment route 100, and the sludge screen 200 occupies a small area, thus effectively utilizing the area of ​​the wastewater treatment plant. Simultaneously, the target quantity is calculated based on the performance improvement goals to be achieved by the main wastewater treatment route 100, ensuring that the sludge screen 200, after installation, can effectively achieve the corresponding performance improvement goals, namely, effectively increasing the total wastewater treatment capacity, thereby effectively improving the treatment capacity, treatment efficiency, and effluent quality of the wastewater treatment plant.

[0141] Based on the same inventive concept, this application also provides a control method for a wastewater treatment system, such as... Figure 4 As shown, in the wastewater treatment system described in the foregoing embodiments, the performance improvement target includes a first target, and the control method includes:

[0142] Monitor the real-time organic sludge percentage in the biological treatment tank 110; in response to the real-time organic sludge percentage being less than a first threshold, close the sludge return pipeline 150 and control all the target number of sludge screens 200 to open; in response to the real-time organic sludge percentage being greater than or equal to the first threshold and less than the first target value corresponding to the first target, close the sludge return pipeline 150 and control a preset number of sludge screens 200 to open; in response to the real-time organic sludge percentage being greater than or equal to the first target value, control the sludge return pipeline 150 to open and close all the target number of sludge screens 200.

[0143] When the primary performance improvement target is to increase the organic matter content in the sludge, the operation of the sludge screener 200 is controlled by monitoring the real-time organic matter sludge content in the biological treatment tank 110. When the biological treatment tank 110 includes an aerobic tank, the operation of the sludge screener 200 can be controlled by monitoring the real-time organic matter sludge content in the aerobic tank. When the real-time organic matter sludge content in the biological treatment tank 110 is less than a first threshold, it indicates that the organic matter content of the sludge in the wastewater treatment system is significantly too low. Therefore, the sludge return pipeline 150 is closed, and the target number of sludge screeners 200 are opened. The sludge from the sedimentation tank 120 enters the sludge screener 200 for screening. Inorganic sludge is discharged to an external sludge storage device through the bottom outlet of the sludge screener 200 and the second sludge discharge pipeline 500, while organic sludge is returned to the biological treatment tank 110 through the overflow outlet and overflow pipeline 400 to continue participating in the reaction, thereby increasing the organic matter content of the sludge in the system.

[0144] When the real-time organic sludge ratio in the biological treatment tank 110 is greater than or equal to the first threshold and less than the first target value, it indicates that although the organic sludge ratio in the sewage treatment system is low, it has not been significantly lower than the first target value. Therefore, the sludge return pipeline 150 is closed and the preset number of sludge screens 200 are turned on. This can increase the organic sludge ratio while saving energy and reducing system operating costs.

[0145] When the ratio of inorganic sludge to organic sludge in the biological treatment tank 110 is greater than or equal to the first target value, it indicates that the organic matter content of the sludge in the wastewater treatment system has reached the first target value. This means the current organic matter content meets the requirements for efficient system operation. At this point, all sludge screens 200 of the target quantity are shut down, and further sludge screening in the system is unnecessary. Sludge return is achieved solely through the sludge return pipeline 150. Specifically, the first threshold can be determined based on the first target value. It can be 1 / 2, 1 / 3, 2 / 3, 1 / 4, 3 / 4, etc., or other values ​​depending on the actual situation. Similarly, the preset quantity can be calculated based on the target quantity. It can be half the target quantity, 1 / 4, 3 / 4, 2 / 5, 3 / 5, 4 / 5, etc., or determined based on the specific target quantity and the specific conditions of the wastewater treatment system.

[0146] Based on the same inventive concept, this application also provides a control method for a wastewater treatment system, such as... Figure 5 As shown, in the wastewater treatment system described in the foregoing embodiments, the performance improvement target includes a second target, and the control method includes:

[0147] The target sludge volume index is determined based on the second target value corresponding to the second target; the real-time sludge volume index in the biological treatment tank 110 is monitored; in response to the real-time sludge volume index being greater than the second threshold, the sludge return pipeline 150 is closed, and all the target number of sludge screens 200 are controlled to operate at a first overflow ratio; in response to the real-time sludge volume index being less than or equal to the second threshold and greater than the target sludge volume index, the sludge return pipeline 150 is closed, and all the target number of sludge screens 200 are controlled to operate at a second overflow ratio; in response to the actual sludge volume index being less than or equal to the target sludge volume index, the sludge return pipeline 150 is opened, and all the target number of sludge screens 200 are closed; wherein, the first overflow ratio is greater than the second overflow ratio.

[0148] After the sludge settling performance of the biological treatment tank 110 is improved, the sludge entering the sedimentation tank 120 settles more easily and is more likely to be returned to the aerobic tank, effectively shortening the sludge-water separation and return time, thereby accelerating the circulation of the entire treatment system, increasing the flow rate of each batch of wastewater treated, and increasing the treatment capacity per unit time. The Sludge Volume Index (SVI) is one of the important indicators for measuring sludge settling performance in wastewater treatment. It represents the volume occupied by a unit weight of sludge after settling within a certain time, reflecting the sludge's settling performance and concentration characteristics. When the performance improvement target is the secondary objective, i.e., increasing the total wastewater treatment capacity, the operation of the sludge screener 200 can be controlled by monitoring the real-time sludge volume index in the biological treatment tank 110. Specifically, when the biological treatment tank 110 includes an aerobic tank, the operation of the sludge screener 200 can be controlled by monitoring the real-time sludge volume index in the aerobic tank.

[0149] The second target value is the increased total wastewater treatment capacity. Therefore, the sludge volume index required to achieve this treatment capacity is calculated based on this value, i.e., the target sludge volume index. Specifically, the target sludge volume index can be determined based on the operating conditions of the main wastewater treatment route 100 before the installation of the sludge screener 200. For example, taking in-situ modification as an example, if the second target value is 1.5 times the original design capacity, then the target sludge volume index can be the sludge volume index of the main wastewater treatment route 100 before modification / 1.5, which is 2 / 3 of the sludge volume index before modification.

[0150] When the real-time sludge volume index of biological tank 110 is greater than the second threshold, it indicates that the volume occupied by a unit mass of sludge is large, reflecting poor sludge settling performance and a large number of poorly settling sludge flocs in the wastewater treatment system. It is necessary to quickly reduce the sludge volume index. At this time, the sludge return pipeline 150 is closed, and all target number of sludge screens 200 are controlled to operate at a high first overflow ratio. More sludge with poor settling performance is discharged to the outside of the system through the overflow port through the sludge screens 200. Sludge with better settling performance moves downward to the underflow port and flows back to biological tank 110 through the underflow port. At the same time, the high-speed rotating fluid inside the sludge screens 200 generates strong turbulence and shear force, which can increase the collision frequency between sludge particles, promote the re-aggregation of flocs into denser particles, and further improve sludge settling. In addition, at the first overflow ratio, the flow rate of the overflow port is high, which can discharge more sludge with poor settling performance, thereby improving the sludge settling performance in the system more quickly.

[0151] When the real-time sludge volume index of the biological treatment tank 110 is less than or equal to the second threshold and greater than the target sludge volume index, it indicates that although the current settling performance is poor, it is close to the target sludge volume index. Therefore, the sludge return pipeline 150 is shut down, and all target-number sludge screens 200 are controlled to operate at a lower second overflow ratio. This improves sludge settling performance and increases the total wastewater treatment capacity while saving energy and reducing system operating costs. When the real-time sludge volume index of the biological treatment tank 110 is less than the target sludge volume index, it indicates that the sludge performance in the wastewater treatment system can handle the total wastewater treatment capacity corresponding to the second target (i.e., the second target value). At this time, all target-number sludge screens 200 are shut down, and it is no longer necessary to screen the sludge in the system. Sludge return is achieved solely through the sludge return pipeline 150.

[0152] Specifically, the second threshold can be determined based on the target sludge volume index (SVI). It can be 1.5 times the SVI (i.e., 1.5SVI), or 1.2, 1.3, 1.4, 1.6, 1.7, 1.8, or 2 times the target sludge volume index (i.e., 1.2SVI, 1.3SVI, 1.4SVI, 1.6SVI, 1.7SVI, 1.8SVI, 2SVI), etc., or other values ​​depending on the actual situation. The first overflow ratio can be 20%, or 25%, 22%, 21%, 19%, 18%, 17%, 16%, 15%, etc., or other values ​​depending on the actual situation. The second overflow ratio can be 10%, or 15%, 12%, 11%, 9%, 8%, 7%, 6%, 5%, etc., or other values ​​depending on the actual situation.

[0153] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a wastewater treatment process design method as described in any of the above embodiments.

[0154] Figure 6 This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0155] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0156] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0157] The input / output interface 1030 is used to connect input / output modules to realize information input and output. Input / output modules can be configured as components within the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touchscreens, microphones, various sensors, etc., while output devices may include displays, speakers, vibrators, indicator lights, etc.

[0158] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0159] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0160] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0161] The electronic devices described above are used to implement a corresponding wastewater treatment process design method in any of the foregoing embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0162] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a non-transitory computer-readable storage medium that stores computer instructions for causing the computer to execute a wastewater treatment process design method as described in any of the above embodiments.

[0163] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0164] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to execute a wastewater treatment process design method as described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0165] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity. Furthermore, while details have been set forth to describe exemplary embodiments of this application, it will be apparent to those skilled in the art that the embodiments of this application can be practiced without these details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0166] To simplify the description and discussion, and to avoid obscuring the embodiments of this application, well-known power / ground connections to other components may or may not be shown in the provided drawings. Furthermore, the apparatus may be shown in block diagram form to avoid obscuring the embodiments of this application, and this also takes into account the fact that the details of implementation of these block diagram apparatuses are highly dependent on the platform on which the embodiments of this application will be implemented (i.e., these details should be fully understood by those skilled in the art). While specific details have been set forth to describe exemplary embodiments of this application, it will be apparent to those skilled in the art that the embodiments of this application may be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive. Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art based on the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0167] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A wastewater treatment process design method, characterized in that, Used to calculate the number of sludge screeners used in wastewater treatment processes, including: Obtain the current organic matter content and current treated water volume of the sludge in the main wastewater treatment route; The performance improvement target is determined based on the current organic matter percentage and the current water volume being treated. The number of sludge screeners used is calculated based on the calculation steps corresponding to the performance improvement target. The performance improvement target includes a first target, and the calculation steps corresponding to the first target include: Based on the first objective, the selection of the sludge screener is determined, and the first specification parameters and initial underflow ratio of the corresponding selected sludge screener are obtained; Obtain the sewage treatment capacity of the main sewage treatment route and the first target value corresponding to the first target, and determine the target operating cycle required to upgrade to the first target value; The first target coefficient is calculated based on the initial underflow ratio, the target operating cycle, and the first target value. The number of sludge screeners to be used is determined based on the wastewater treatment scale, the first target coefficient, and the first specification parameters. The first objective is to increase the proportion of organic matter in the sludge, the first specification parameter is the design capacity of the sludge screener, and the first objective value is the increased proportion of organic matter.

2. The wastewater treatment process design method according to claim 1, characterized in that, The first target coefficient is calculated using the following formula: in, For the first target value, For the target running cycle, The first target coefficient, The current organic sludge quality of the main wastewater treatment route. This refers to the daily increase in the mass of organic sludge in the main wastewater treatment route. The mass of organic sludge discharged daily from the main wastewater treatment route. The current inorganic sludge quality of the main wastewater treatment route. This refers to the daily increase in the mass of inorganic sludge in the main wastewater treatment process. The mass of inorganic sludge discharged daily from the main wastewater treatment route; The concentration of the sludge returned from the main wastewater treatment route is [missing information]. The inorganic sludge ratio constant in the sludge discharged from the sludge screener is [missing information]. The initial underflow ratio, The scale of the wastewater treatment plant; The daily increase in organic sludge in the main wastewater treatment route is calculated using the following formula: The daily increase in inorganic sludge in the main wastewater treatment route is calculated using the following formula: in, This is the sludge yield coefficient. The design scale of the main sewage treatment route is given. The BOD5 of the influent to the main wastewater treatment line is... The BOD5 of the effluent from the main wastewater treatment line is... Here, V is the endogenous metabolic coefficient, V is the volume of the biological treatment tank in the main wastewater treatment route, and f is the current percentage of organic sludge in the main wastewater treatment route. The current sludge concentration in the main wastewater treatment route. The suspended solids concentration in the influent of the main wastewater treatment route. The concentration of suspended solids in the effluent from the main wastewater treatment route.

3. The wastewater treatment process design method according to claim 1, characterized in that, The step of determining the number of sludge screeners to be used based on the wastewater treatment scale, the first target coefficient, and the first specification parameters includes: The initial number of sludge screeners is calculated based on the wastewater treatment scale, the first target coefficient, and the first specification parameters. In response to the calculated initial quantity being an integer, the initial quantity is determined to be the final number of sludge screeners used; In response to the initial quantity being non-integer, the smallest integer greater than the initial quantity is determined as the final number of sludge screeners used; The initial number of sludge screeners is calculated using the following formula: The initial quantity, For the first target coefficient, The scale of the wastewater treatment plant is mentioned. This refers to the first specification parameter.

4. The wastewater treatment process design method according to claim 1, characterized in that, The performance improvement objective includes a second objective, and the calculation steps corresponding to the second objective include: Based on the second objective, the selection of the sludge screener is determined, and the second specification parameters and initial overflow ratio of the corresponding selected sludge screener are obtained; Obtain the second target value corresponding to the second target and the sludge discharge constant of the main sewage treatment route; The second target coefficient is determined based on the sludge discharge constant and the initial overflow ratio; The number of sludge screeners used is determined based on the second target coefficient, the second target value, and the second specification parameters. The second objective is to increase the total amount of wastewater treated, the second objective value is the increased total amount of wastewater treated, and the second specification parameter is the design capacity of the sludge screener.

5. A wastewater treatment process design method according to claim 1 or 4, characterized in that, The sludge screener selected for the same performance improvement objective may be one or more types.

6. A wastewater treatment system, characterized in that, The system includes a main wastewater treatment route and a target number of sludge screens; each of the sludge screens includes an inlet located on the side wall, an underflow outlet located at the bottom, and an overflow outlet located at the top. The main sewage treatment route includes a biological treatment tank and a sedimentation tank. One side of the biological treatment tank is connected to an inlet pipeline, and the opposite side is connected to the sedimentation tank. The sedimentation tank is connected to a drainage pipeline at the top to discharge the treated wastewater to the next stage, and is connected to the biological treatment tank at the bottom through a sludge return pipeline. The target number of sludge screens are arranged in parallel, and the inlet of each sludge screen is connected to the bottom of the sedimentation tank through a first sludge discharge pipeline, the overflow outlet is connected to the biological treatment tank through an overflow pipeline, and the bottom outlet is connected to an external sludge storage device through a second sludge discharge pipeline. The sludge screens are used to screen the sludge discharged from the sedimentation tank and return the screened sludge to the biological treatment tank through the overflow pipeline. The target quantity is calculated according to any one of claims 1 to 5 of the wastewater treatment process design method.

7. A wastewater treatment system, characterized in that, The system includes a main wastewater treatment route and a target number of sludge screens; each of the sludge screens includes an inlet located on the side wall, an underflow outlet located at the bottom, and an overflow outlet located at the top. The main sewage treatment route includes a biological treatment tank and a sedimentation tank. One side of the biological treatment tank is connected to an inlet pipeline, and the opposite side is connected to the sedimentation tank. The sedimentation tank is connected to a drainage pipeline at the top to discharge the treated wastewater to the next stage, and is connected to the biological treatment tank at the bottom through a sludge return pipeline. The target number of sludge screens are arranged in parallel, and the inlet of each sludge screen is connected to the bottom of the sedimentation tank through a first sludge discharge pipeline, the overflow outlet is connected to an external sludge storage device through an overflow pipeline, and the bottom outlet is connected to the biological treatment tank through a second sludge discharge pipeline. The sludge screens are used to screen the sludge discharged from the sedimentation tank and return the screened sludge to the biological treatment tank through the second sludge discharge pipeline. The target quantity is calculated according to any one of claims 1 to 5 of the wastewater treatment process design method.

8. A control method for a wastewater treatment system, characterized in that, Applied to a wastewater treatment system according to claim 6, the performance improvement target includes a first target, and the control method includes: Monitor the real-time organic sludge ratio in the biochemical tank; In response to the real-time organic sludge ratio being less than a first threshold, the sludge return pipeline is shut down, and all the target number of sludge screens are turned on. In response to the real-time organic sludge ratio being greater than or equal to the first threshold and less than the first target value corresponding to the first target, the sludge return pipeline is shut down, and a preset number of sludge screens are turned on. In response to the real-time organic sludge ratio being greater than or equal to the first target value, the sludge return pipeline is opened, and all the target number of sludge screens are closed.

9. A control method for a wastewater treatment system, characterized in that, Applied to the wastewater treatment system of claim 7, the performance improvement objective includes a second objective, and the control method includes: The target sludge volume index is determined based on the second target value corresponding to the second target. Monitor the real-time sludge volume index in the biological treatment tank; In response to the real-time sludge volume index being greater than a second threshold, the sludge return pipeline is shut off, and all the target number of sludge screens are controlled to operate at a first overflow ratio. In response to the real-time sludge volume index being less than or equal to the second threshold and greater than the target sludge volume index, the sludge return pipeline is shut down, and all the target number of sludge screens are controlled to operate at the second overflow ratio. In response to the real-time sludge volume index being less than or equal to the target sludge volume index, the sludge return pipeline is opened, and all the target number of sludge screens are closed. Wherein, the first overflow ratio is greater than the second overflow ratio.

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