Preprocessing method and system for turbidity fluctuation of raw water of water plant considering mountainous rainstorm confluence process

Abstract

The application belongs to the technical field of water treatment, and discloses a water plant raw water turbidity fluctuation pretreatment method and system considering mountainous rainstorm confluence process, which can adaptively process the problems of raw water turbidity sudden rise, instantaneous flow impact and water quality rapid fluctuation in the mountainous rainstorm confluence process. The rainstorm confluence state is judged through the inlet water turbidity data, the high-turbidity water at the initial stage of rainstorm can be identified in time, and the system is prevented from being passively operated according to the fixed process. When the inlet water turbidity meets the initial rainstorm confluence condition, the initial high-turbidity raw water is diverted to the initial water collection tank and temporarily settled, which can reduce the direct entry of silt, suspended matter and sundries into the subsequent treatment unit, and reduce the risk of filter screen blockage, sudden increase of sedimentation load and system impact.

Description

Technical Field

[0001] This invention pertains to the field of water treatment technology, specifically relating to a method and system for pretreatment of raw water turbidity fluctuations in water plants that takes into account the confluence process of torrential rains in mountainous areas. Background Technology

[0002] Raw water pretreatment is the initial stage in the water treatment process, primarily used to remove suspended impurities, silt, colloidal particles, and other pollutants from raw water, providing relatively stable influent conditions for subsequent conventional treatment processes such as coagulation, sedimentation, filtration, and disinfection. Existing raw water pretreatment in water plants typically employs processes such as sedimentation, filtration, and chemical coagulation, which are effective for raw water with minimal quality fluctuations and relatively stable flow rates.

[0003] However, the raw water for mountain water plants mostly originates from mountain streams, small reservoirs, or surface runoff. Affected by factors such as the steep slopes of mountainous terrain, short runoff paths, differences in vegetation cover, and variations in rainfall intensity, the quality of the raw water is prone to drastic fluctuations during heavy rain. In the initial stages of a heavy rainstorm, rainwater rapidly washes away the surface layer of the mountain, carrying large amounts of silt, humus, fallen leaves, and other suspended debris into the water intake point, causing a rapid increase in the turbidity of the raw water within a short period, accompanied by instantaneous flow surges.

[0004] Existing pretreatment systems mostly follow the conventional treatment model of water plants in plain areas, usually relying on a single sedimentation or filtration unit for pretreatment, lacking specialized buffering, diversion, and staged interception measures for storm runoff processes in mountainous areas. When high-turbidity raw water directly enters subsequent treatment units, it can easily cause problems such as filter clogging, sudden increase in sedimentation load, and imbalance in reagent dosage, and in severe cases, it can also affect the stable operation of subsequent conventional treatment systems.

[0005] In addition, the existing pretreatment systems mostly operate independently between treatment units, lacking a mechanism for real-time linkage adjustment based on raw water turbidity, flow rate, and treatment effect. Operations such as chemical dosing, backwashing, and sludge removal still rely heavily on manual experience, making it difficult to adapt to the large fluctuations and rapid changes in turbidity during the confluence of torrential rains in mountainous areas. Summary of the Invention

[0006] The purpose of this invention is to overcome the difficulties that existing water plant raw water pretreatment methods and systems face in adapting to the conditions of sudden increases in raw water turbidity, instantaneous flow impacts, and rapid fluctuations in water quality during the convergence of torrential rains in mountainous areas. This results in high-turbidity raw water easily impacting subsequent treatment units, leading to problems such as filter clogging, unbalanced reagent dosing, and unstable treatment processes. The invention provides a water plant raw water turbidity pretreatment method and system that takes into account the turbidity fluctuations during the convergence of torrential rains in mountainous areas.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for pretreatment of raw water turbidity fluctuations in water treatment plants that takes into account the runoff process of torrential rains in mountainous areas, comprising the following steps: Obtain the influent turbidity data at the raw water intake point in the mountainous area, and determine the storm runoff state of the raw water based on the influent turbidity data; When the influent turbidity data meets the initial rainstorm confluence conditions, the influent from the mountain raw water intake is diverted to the initial water collection pond, and the initial high turbidity raw water is temporarily treated by sedimentation in the initial water collection pond. When the influent turbidity data meets the pretreatment influent conditions, the raw water in the mountainous area is buffered and the initial sediments are discharged. The raw water after the confluence buffer is subjected to coarse filtration, fine filtration and colloidal stabilization and destruction treatment in sequence to complete the graded pretreatment; Adjust the dosage of the reagent in the pre-treated raw water according to the turbidity test results to mix the reagent with the raw water; The raw water after mixing the chemicals is precipitated and clarified, and the sludge is discharged to obtain pretreated effluent. Turbidity data is collected during the confluence buffer, staged pretreatment, sedimentation and clarification, and sludge removal. Based on the turbidity data, the operating parameters in the initial raw water diversion, backwashing, chemical dosing, stirring, or sludge discharge are adjusted.

[0008] A further improvement of the present invention is that the initial rainstorm confluence condition is that the turbidity of the incoming water at the raw water intake end in the mountainous area is greater than the preset turbidity threshold.

[0009] A further improvement of the present invention is that when the incoming water from the mountain raw water intake is diverted to the initial water collection tank, the incoming water from the inlet is switched to the diversion pipe through the diversion valve, so that the initial raw water enters the initial water collection tank and undergoes sedimentation and separation through the sedimentation layer and permeable baffle in the initial water collection tank. The sediment is discharged through the temporary sludge discharge pipe.

[0010] A further improvement of the present invention is that, when the raw water in the mountainous area is buffered and discharged, the raw water flows along the spiral guide plate set on the inner wall of the buffer pool body, thereby extending the flow path of the raw water in the buffer pool body.

[0011] A further improvement of this invention lies in the fact that the raw water after the confluence buffer is subjected to coarse filtration, fine filtration, and colloidal stabilization and destruction treatment in sequence to complete the graded pretreatment. The specific method is as follows: The coarse filtration process uses a stainless steel filter screen to intercept suspended impurities. The backwash nozzle is activated when the filter screen becomes clogged or the turbidity increases. Fine filtration uses a pleated polypropylene filter membrane to trap suspended particles; The colloidal stabilization and destruction treatment involves stirring the finely filtered raw water using a stirrer.

[0012] A further improvement of the present invention is that the colloidal stability destruction treatment includes pH adjustment, which involves adding dilute sulfuric acid or sodium hydroxide solution to the colloidal particles to adjust the stability of the colloidal particles in the raw water.

[0013] A further improvement of this invention lies in adjusting the dosage of the reagent in the pre-treated raw water according to the turbidity detection results, and the specific method for mixing the reagent with the raw water is as follows: Polyaluminum chloride and polyacrylamide are added to the pretreated raw water. The reagents are delivered to the dosing pipeline by a metering pump and mixed with the pretreated raw water by a mixer.

[0014] A further improvement of the present invention is that, before the agent is delivered to the dosing pipeline by a metering pump, the concentration of the agent to be added is collected, and the agent is stirred according to the concentration of the agent to be added.

[0015] A further improvement of this invention lies in the following specific method for precipitating and clarifying the raw water after mixing the reagents and discharging the sludge to obtain pretreated effluent: The raw water after the reagents are mixed is sent to a clarification tank for sedimentation and clarification. The settled sludge is discharged to an external sludge treatment device through a sludge discharge pump to obtain pretreated effluent.

[0016] Secondly, the present invention provides a pretreatment system for raw water turbidity fluctuations in water treatment plants that takes into account the runoff process of torrential rains in mountainous areas, comprising: The data acquisition module is used to acquire the turbidity data of the raw water intake in the mountainous area, and to determine the storm runoff state of the raw water based on the turbidity data. The sedimentation treatment module is used to divert the incoming water from the mountain raw water intake to the initial water collection pool when the influent turbidity data meets the initial rainstorm confluence conditions, and to temporarily sediment the initial high turbidity raw water through the initial water collection pool. The confluence buffer module is used to confluence and buffer the raw water in the mountainous area when the influent turbidity data meets the pretreatment influent conditions, and to discharge the initial sediments. The graded pretreatment module is used to sequentially perform coarse filtration, fine filtration and colloidal stabilization and destruction treatment on the raw water after the confluence buffer to complete the graded pretreatment. The dosing module is used to adjust the amount of chemicals added to the pre-treated raw water according to the turbidity detection results, so that the chemicals are mixed with the raw water. The sedimentation module is used to settle and clarify the raw water after the reagents are mixed and to discharge the sludge to obtain pretreated effluent. The feedback control module is used to collect turbidity data during the confluence buffering, staged pretreatment, sedimentation and clarification, and sludge removal processes. Based on the turbidity data, the module adjusts the operating parameters during initial raw water flow, backwashing, chemical dosing, stirring, or sludge discharge.

[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention provides adaptive solutions to the problems of sudden increases in raw water turbidity, instantaneous flow surges, and rapid fluctuations in water quality during torrential rain runoff in mountainous areas. By analyzing influent turbidity data to determine the storm runoff status, it can promptly identify high-turbidity influent at the initial stage of a storm, preventing the system from passively operating according to a fixed process. When the influent turbidity meets the initial storm runoff conditions, the initial high-turbidity raw water is diverted to an initial water collection tank for temporary sedimentation, reducing the direct entry of silt, suspended solids, and debris into subsequent treatment units, thus mitigating filter clogging, sudden increases in sedimentation load, and the risk of system shock. After meeting the pretreatment influent conditions, the mountainous raw water is buffered through runoff and preliminary sediments are discharged, which weakens instantaneous flow surges and improves the continuity of subsequent treatment. Through staged pretreatment involving coarse filtration, fine filtration, and colloidal stabilization disruption, large particulate impurities, fine suspended particles, and colloidal pollutants can be removed in stages, providing stable influent for subsequent reagent mixing and sedimentation clarification. Adjusting the dosage of chemicals based on turbidity test results, and combining turbidity data with the coordinated control of parameters such as diversion, backwashing, stirring, and sludge discharge, can reduce the problem of insufficient or excessive dosage caused by manual experience control, improve the stability of pretreated effluent, and ensure the safe operation of subsequent conventional treatment systems. Attached Figure Description

[0018] Figure 1 This is a flowchart of the present invention; Figure 2 This is a schematic diagram of the closed-loop control principle of turbidity feedback regulation according to the present invention; Figure 3 This is a system diagram of the present invention. Detailed Implementation

[0019] To further understand the content of this invention, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments are merely illustrative and not limiting of the invention.

[0020] Example 1: See Figure 1 This embodiment is applicable to the pretreatment of raw water turbidity surges, instantaneous flow surges, and rapid water quality fluctuations during rainstorm confluence in mountainous water plants. The method can be implemented by a raw water turbidity fluctuation pretreatment system, including a confluence buffer unit, a staged pretreatment unit, an intelligent reagent dosing unit, a deep clarification unit, and a turbidity feedback control unit connected in sequence. The confluence buffer unit is connected to the raw water intake in the mountainous area, and the deep clarification unit is connected to the subsequent conventional treatment system of the water plant. A first connecting pipeline is provided between the confluence buffer unit and the staged pretreatment unit, a second connecting pipeline is provided between the staged pretreatment unit and the intelligent reagent dosing unit, a third connecting pipeline is provided between the intelligent reagent dosing unit and the deep clarification unit, and a signal transmission line is provided between the deep clarification unit and the turbidity feedback control unit.

[0021] The confluence and buffer unit is used for confluence and buffering of raw water in mountainous areas, initial raw water diversion, and initial sediment discharge. The unit includes a buffer tank body, a spiral guide plate, a diversion valve, a diversion pipe, and an initial water collection tank. The spiral guide plate is installed along the length of the buffer tank body and fixed to its inner wall; the spiral guide plate can be integrated with the buffer tank body. The inner wall of the buffer tank body is coated with an anti-corrosion coating, covering the entire surface to reduce wear and corrosion caused by silt and corrosive substances in the raw water. An inspection port with a sealing cover is located at the top of the buffer tank body for easy inspection and maintenance of its internal structure. A sludge discharge pipe with a control valve is located at the bottom of the buffer tank body to discharge large particles of impurities that settle at the bottom.

[0022] A diversion valve is installed at the inlet end of the buffer tank. The input end of the valve connects to the water intake pipeline at the mountainous raw water intake point. The output end of the valve splits into two paths: one connects to the interior of the buffer tank, and the other connects to the initial water collection tank via a diversion pipe. The diversion valve is electrically connected to a turbidity feedback control unit, enabling it to switch the inlet flow direction based on inlet turbidity data. The initial water collection tank contains a sedimentation layer, which can be made of quartz sand. A permeable baffle is installed below the sedimentation layer, with a gap between the baffle and the bottom of the initial water collection tank. This gap connects to a temporary sludge discharge pipe. This temporary sludge discharge pipe connects to the sludge discharge pipe at the bottom of the buffer tank, allowing the settled sediment, sludge, and suspended impurities in the initial water collection tank to be discharged uniformly.

[0023] The staged pretreatment unit is used to sequentially perform coarse filtration, fine filtration, and colloidal stabilization / degradation treatment on the raw water after the confluence buffer. The staged pretreatment unit includes a coarse filtration module, a fine filtration module, and a colloidal stabilization / degradation module connected in sequence. The coarse filtration module, fine filtration module, and colloidal stabilization / degradation module are connected by sealed pipelines, and all three can adopt a sealed shell structure to reduce leakage during the treatment process.

[0024] The coarse filtration module contains a filter frame, a stainless steel filter screen, backwash nozzles, and backwash piping. The stainless steel filter screen is fixed to the filter frame, which is slidably connected to the coarse filtration module housing for easy disassembly and replacement. The stainless steel filter screen can be a wedge-shaped mesh structure to intercept large suspended impurities, silt, and debris such as dead leaves and branches in the raw water from mountainous areas. Backwash nozzles are located on one side of the filter screen surface; these nozzles can be rotary and connected to the backwash piping. The backwash piping extends to the outside of the coarse filtration module and is equipped with a control valve connected to a turbidity feedback control unit to activate the backwash nozzles when the filter screen becomes clogged or turbidity increases.

[0025] The fine filtration module contains a membrane support and a pleated polypropylene membrane. The pleated polypropylene membrane is fixed to the membrane support, which is located inside the fine filtration module housing. The inlet of the fine filtration module is connected to the outlet of the coarse filtration module, and the outlet of the fine filtration module is connected to the inlet of the colloidal stabilization and decomposition module. After coarse filtration, the raw water enters the fine filtration module, where the pleated polypropylene membrane traps fine suspended particles and colloidal impurities.

[0026] The colloidal stabilization and destruction module is equipped with a stirrer, which can be a high-frequency stirrer. Its stirring shaft extends into the module, and the stirring blades are fixed to the end of the shaft. The stirrer is connected to a turbidity feedback control unit, allowing adjustment of the stirring state based on turbidity data. The module also includes a pH adjustment device, comprising a reagent storage component and a delivery pipeline. The reagent storage component stores dilute sulfuric acid or sodium hydroxide solution. One end of the delivery pipeline connects to the reagent storage component, and the other end extends into the module. By adding dilute sulfuric acid or sodium hydroxide solution to the module, the stability of colloidal particles in the raw water can be adjusted, creating conditions for subsequent reagent mixing and precipitation clarification.

[0027] The intelligent reagent dosing unit adjusts the reagent dosage in the pre-treated raw water based on turbidity detection results and mixes the reagent with the raw water. The intelligent reagent dosing unit includes a reagent storage tank, a metering pump, a dosing pipeline, and a mixer. At least two reagent storage tanks are provided, one for storing polyaluminum chloride and the other for polyacrylamide. Each storage tank has a reagent filling port and a sealing cap on top, and a reagent outlet on the bottom. A filter screen can be installed at the outlet to filter impurities in the reagent and reduce metering pump clogging. One end of the metering pump is connected to the outlet of the reagent storage tank, and the other end is connected to the dosing pipeline. The metering pump is connected to a turbidity feedback control unit, which can adjust the reagent dosage according to control signals. A one-way valve is installed at the outlet of the metering pump, connected to the dosing pipeline, to prevent raw water in the pipeline from flowing back into the reagent storage tank.

[0028] A mixer is installed in the dosing pipeline. This mixer can be a static mixer, and its outlet extends to the connecting pipeline between the staged pretreatment unit and the deep clarification unit. A sealing and insulation layer can be installed on the surface of the dosing pipeline to reduce the impact of ambient temperature changes on the stability of the reagent delivery. The intelligent reagent dosing unit also includes a reagent concentration monitoring module, which comprises a concentration sensor and a stirring device. The concentration sensor is located inside the reagent storage tank and is used to collect the concentration of the reagent to be added. The stirring device is located at the bottom of the reagent storage tank and is connected to the turbidity feedback control unit to stir the reagent according to its concentration, ensuring a uniform and stable concentration.

[0029] The deep clarification unit is used to settle and clarify the raw water after reagent mixing and to discharge sludge, resulting in pretreated effluent. The deep clarification unit includes a clarification tank body, inclined tube sedimentation components, a sludge thickening hopper, a sludge pump, a sludge scraper, and an overflow trough. The clarification tank body is connected to the intelligent reagent dosing unit, and the raw water after reagent mixing enters the clarification tank body for sedimentation and clarification. The inclined tube sedimentation components can be honeycomb-type inclined tubes, fixed to a support inside the clarification tank body, to improve the floc settling efficiency. A sludge thickening hopper is located below the inclined tube sedimentation components, fixed to the bottom of the clarification tank body and shaped like an inverted cone. A sludge pump is located at the bottom of the sludge thickening hopper, connected to external sludge treatment equipment, to discharge settled sludge to the external sludge treatment equipment.

[0030] The sludge scraper is located inside the clarifier body. It can employ a bridge-type scraping structure and is fixed to the top of the clarifier body via a bracket. The scraper is equipped with scraper blades connected to its drive unit. These blades are positioned against the bottom of the clarifier body to scrape the settled sludge from the bottom to the sludge thickening hopper. An overflow trough is located at the top edge of the clarifier body. A baffle plate is installed inside the overflow trough and is vertically fixed to the bottom to intercept scum generated during the clarification process. The outlet of the overflow trough connects to the effluent pipeline of the deep clarification unit, which in turn connects to the subsequent conventional treatment system of the water plant, allowing the pretreated effluent to enter the subsequent treatment stages.

[0031] The turbidity feedback control unit is used to collect turbidity data during the confluence buffering process, staged pretreatment, sedimentation and clarification, and sludge treatment. Based on the turbidity data, it adjusts the operating parameters for initial raw water diversion, backwashing, reagent dosing, agitation, and sludge discharge. The turbidity feedback control unit includes multiple turbidity sensors, a data acquisition module, a PLC controller, and an execution module. Multiple turbidity sensors are respectively installed at the inlet of the confluence buffering unit, the inlet and outlet of the staged pretreatment unit, and the inlet and outlet of the deep clarification unit. Each turbidity sensor is electrically connected to the data acquisition module. The data acquisition module is electrically connected to the PLC controller, and the PLC controller is electrically connected to the execution module. The execution module is connected to the diversion valve, backwash nozzle, metering pump, agitator, agitation device in the reagent storage tank, sludge pump, and scraper.

[0032] Example 2: See Figure 2 In actual operation, the turbidity data of the incoming water at the mountainous raw water intake is first acquired. Specifically, a turbidity sensor installed at the inlet of the confluence buffer unit collects the inlet turbidity data in real time and sends it to the data acquisition module. The data acquisition module processes and converts the inlet turbidity data before sending it to the PLC controller. The PLC controller determines the storm flow confluence state of the raw water based on the inlet turbidity data.

[0033] When the turbidity of the influent at the mountain raw water intake exceeds the preset turbidity threshold, the influent turbidity data is determined to meet the initial storm runoff confluence conditions. At this time, the PLC controller controls the diversion valve through the execution module to switch the influent from the mountain raw water intake to the diversion pipe, allowing the initial raw water to enter the initial water collection tank. The initial high-turbidity raw water entering the initial water collection tank undergoes sedimentation separation through the sedimentation layer and permeable baffle. Mud, sludge, and suspended impurities settle in the sedimentation layer and the bottom area of ​​the tank. The sediment collects through the gaps below the permeable baffle and is discharged through the temporary sludge discharge pipe. Since the temporary sludge discharge pipe is connected to the sludge discharge pipe at the bottom of the buffer tank, the sediment in the initial water collection tank can be discharged together with the sediment at the bottom of the buffer tank.

[0034] When the influent turbidity data meets the pretreatment influent conditions, the PLC controller switches the diversion valve, allowing the raw water from the mountainous area to enter the buffer tank. The raw water flows along the spiral guide plates installed on the inner wall of the buffer tank. The spiral guide plates extend the flow path of the raw water within the buffer tank, weakening the instantaneous hydraulic impact generated by the rainstorm confluence, and causing large particles of silt and suspended impurities in the raw water to gradually settle to the bottom of the buffer tank during the flow process. The initial sediment deposited at the bottom of the buffer tank is discharged through the sludge discharge pipe.

[0035] After being buffered, the raw water enters the staged pretreatment unit through the first connecting pipeline, where it undergoes coarse filtration, fine filtration, and colloidal stabilization treatment in sequence. The coarse filtration uses a stainless steel filter screen to intercept suspended impurities, especially large particles of silt, fallen leaves, and debris. During coarse filtration, the turbidity feedback control unit can determine whether the filter screen is clogged or its treatment capacity has decreased based on the turbidity data at the inlet and outlet of the coarse filtration module, the pressure difference data before and after the filter screen, or a preset operating cycle. When the filter screen is clogged or the turbidity increases, the PLC controller opens the control valve on the backwash pipeline and activates the backwash nozzles to backwash the stainless steel filter screen. The backwash wastewater is discharged through the sludge discharge pipe.

[0036] After coarse filtration, the raw water enters the fine filtration module. Fine filtration uses a pleated polypropylene membrane to trap suspended particles, further removing fine particles and colloidal impurities. The finely filtered raw water then enters the colloid stabilization and destruction module. This module uses a stirrer to agitate the filtered raw water. During agitation, depending on the pH value of the raw water or the stable state of the colloidal particles, dilute sulfuric acid or sodium hydroxide solution can be added to the colloid stabilization and destruction module via a pH adjustment device to adjust the stability of the colloidal particles in the raw water, making them more likely to form flocs during subsequent chemical dosing.

[0037] After the raw water undergoes staged pretreatment, it enters the dosing stage. Based on the turbidity detection results, the PLC controller adjusts the dosage of chemicals in the staged pretreatment raw water. Specifically, the turbidity feedback control unit collects the turbidity of the staged pretreatment raw water and the turbidity of the effluent after sedimentation and clarification, and the PLC controller controls the dosing flow rate of the metering pump based on the above turbidity data. Polyaluminum chloride and polyacrylamide are added to the staged pretreatment raw water. The chemicals in the chemical storage tank are delivered to the dosing pipeline by the metering pump, and then the chemicals are thoroughly mixed with the staged pretreatment raw water by a mixer.

[0038] Before the reagent is delivered to the dosing pipeline by a metering pump, a concentration sensor collects the concentration of the reagent to be added. If the reagent concentration is below the preset range, or if the concentration distribution is uneven, the PLC controller activates the agitator at the bottom of the reagent storage tank to stir the reagent, ensuring a uniform and stable concentration of polyaluminum chloride or polyacrylamide. Afterward, the metering pump delivers the reagent to the dosing pipeline, where it is mixed with the raw water via a mixer.

[0039] After the reagents are mixed, the raw water enters the sedimentation and clarification stage. Specifically, the raw water mixed with the reagents is sent to the clarification tank for sedimentation and clarification. The raw water flows through the inclined tube sedimentation unit, where the flocs formed by the reagent mixing settle under the action of the inclined tube sedimentation unit. The settled sludge enters the sludge thickening hopper and is discharged to external sludge treatment equipment by the sludge discharge pump to obtain pretreated effluent. During the sludge discharge process, the sludge scraper can operate synchronously or periodically, scraping the sludge deposited at the bottom of the clarification tank into the sludge thickening hopper to prevent sludge accumulation at the bottom of the tank from affecting the sedimentation and clarification effect. The clarified supernatant is collected in the overflow trough, and after the scum is intercepted by the baffle plate, it enters the subsequent conventional treatment system of the water plant through the effluent pipeline.

[0040] Throughout the pretreatment process, the feedback control module continuously collects turbidity data during the confluence buffer, staged pretreatment, sedimentation and clarification, and sludge discharge. Based on this turbidity data, it adjusts operating parameters for initial raw water diversion, backwashing, reagent dosing, agitation, and sludge discharge. For example, when the influent turbidity during the confluence buffer exceeds a preset turbidity threshold, the diversion valve directs the initial raw water into the initial water collection tank; when the turbidity increases during staged pretreatment or the filter becomes clogged, the backwash nozzles are activated; when the turbidity of the raw water after staged pretreatment increases, the dosage of polyaluminum chloride or polyacrylamide is increased, or the agitator's operating status is adjusted; when the turbidity of the effluent after sedimentation and clarification increases, the reagent dosage, sludge pump start / stop, or scraper operation cycle are adjusted. Through this coordinated control, the pretreatment process can adapt to the conditions of rapid changes and large fluctuations in raw water turbidity and significant instantaneous flow impacts during mountainous rainstorm confluence.

[0041] Example 3: See Figure 2This embodiment also provides a water plant raw water turbidity fluctuation pretreatment system considering the confluence process of mountainous rainstorms. The system includes a data acquisition module, a sedimentation treatment module, a confluence buffer module, a staged pretreatment module, a dosing module, a sedimentation module, and a feedback control module. The data acquisition module acquires the influent turbidity data at the mountainous raw water intake point and determines the rainstorm confluence state of the raw water based on the influent turbidity data. The sedimentation treatment module, when the influent turbidity data meets the initial rainstorm confluence conditions, diverts the influent from the mountainous raw water intake point to an initial water collection tank, and performs temporary sedimentation treatment on the initially high-turbidity raw water in the initial water collection tank. The confluence buffer module, when the influent turbidity data meets the pretreatment influent conditions, performs confluence buffering on the mountainous raw water and discharges preliminary sediments. The staged pretreatment module sequentially performs coarse filtration, fine filtration, and colloidal stabilization treatment on the buffered raw water to complete the staged pretreatment. The dosing module adjusts the dosage of chemicals in the pre-treated raw water based on turbidity detection results, ensuring proper mixing of chemicals with the raw water. The sedimentation module clarifies the mixed raw water through sedimentation and sludge discharge, yielding pre-treated effluent. The feedback control module collects turbidity data during confluence buffering, pre-treatment, sedimentation, clarification, and sludge discharge, and adjusts operating parameters for initial raw water flow, backwashing, chemical dosing, agitation, and sludge discharge based on this data.

[0042] Through the above-described embodiments, this invention can sequentially complete the following steps before raw water from mountainous areas enters the subsequent conventional treatment system of the water plant: storm runoff identification, initial high-turbidity raw water diversion, temporary sedimentation, runoff buffering, coarse filtration, fine filtration, colloidal stabilization and disruption, reagent mixing, sedimentation and clarification, sludge discharge, and turbidity feedback control. This method and system can prevent high-turbidity raw water from directly impacting subsequent treatment units at the beginning of storms, reducing the risks of filter clogging, reagent dosing imbalances, and sudden increases in sedimentation load, and improving the stability and automation of raw water pretreatment in mountainous water plants.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A pretreatment method for raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, characterized in that, Includes the following steps: Obtain the influent turbidity data at the raw water intake point in the mountainous area, and determine the storm runoff state of the raw water based on the influent turbidity data; When the influent turbidity data meets the initial rainstorm confluence conditions, the influent from the mountain raw water intake is diverted to the initial water collection pond, and the initial high turbidity raw water is temporarily treated by sedimentation in the initial water collection pond. When the influent turbidity data meets the pretreatment influent conditions, the raw water in the mountainous area is buffered and the initial sediments are discharged. The raw water after the confluence buffer is subjected to coarse filtration, fine filtration and colloidal stabilization and destruction treatment in sequence to complete the graded pretreatment; Adjust the dosage of the reagent in the pre-treated raw water according to the turbidity test results to mix the reagent with the raw water; The raw water after mixing the chemicals is precipitated and clarified, and the sludge is discharged to obtain pretreated effluent. Turbidity data is collected during the confluence buffer, staged pretreatment, sedimentation and clarification, and sludge removal. Based on the turbidity data, the operating parameters in the initial raw water diversion, backwashing, chemical dosing, stirring, or sludge discharge are adjusted.

2. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 1, is characterized in that... The initial rainstorm runoff conditions are that the turbidity of the incoming water at the raw water intake in the mountainous area is greater than the preset turbidity threshold.

3. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 1, is characterized in that... When the incoming water from the mountainous raw water intake is diverted to the initial water collection tank, the water from the inlet is switched to the diversion pipe through the diversion valve, so that the initial raw water enters the initial water collection tank. In the initial water collection tank, the water undergoes sedimentation and separation through the sedimentation layer and permeable baffle. The sediment is discharged through the temporary sludge discharge pipe.

4. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 1, is characterized in that... When the raw water in the mountainous area is buffered and discharged after initial sedimentation, the raw water flows along the spiral guide plate set on the inner wall of the buffer tank, extending the flow path of the raw water within the buffer tank.

5. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 1, is characterized in that... The raw water after the confluence buffer is subjected to coarse filtration, fine filtration, and colloidal stabilization and destruction treatment in sequence to complete the staged pretreatment. The specific method is as follows: The coarse filtration process uses a stainless steel filter screen to intercept suspended impurities. The backwash nozzle is activated when the filter screen becomes clogged or the turbidity increases. Fine filtration uses a pleated polypropylene filter membrane to trap suspended particles; The colloidal stabilization and destruction treatment involves stirring the finely filtered raw water using a stirrer.

6. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 1 or 5, is characterized in that... Colloidal stability disruption treatment includes pH adjustment, adding dilute sulfuric acid or sodium hydroxide solution to the colloids to adjust the stability of colloidal particles in the raw water.

7. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 1, is characterized in that... The specific method for adjusting the dosage of the reagent in the pre-treated raw water according to the turbidity test results, and mixing the reagent with the raw water, is as follows: Polyaluminum chloride and polyacrylamide are added to the pretreated raw water. The reagents are delivered to the dosing pipeline by a metering pump and mixed with the pretreated raw water by a mixer.

8. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 7, is characterized in that... Before the reagent is delivered to the dosing pipeline by a metering pump, the concentration of the reagent to be added is collected, and the reagent is stirred according to the concentration of the reagent to be added.

9. The method for pretreatment of raw water turbidity fluctuations in water plants considering the confluence process of torrential rain in mountainous areas, as described in claim 7, is characterized in that... The specific method for obtaining pretreated effluent by sedimentation and clarification of the raw water after mixing the chemicals and discharging the sludge is as follows: The raw water after the reagents are mixed is sent to a clarification tank for sedimentation and clarification. The settled sludge is discharged to an external sludge treatment device through a sludge discharge pump to obtain pretreated effluent.

10. A pretreatment system for raw water turbidity fluctuations in a water plant considering the runoff process of torrential rain in mountainous areas, characterized in that, include: The data acquisition module is used to acquire the turbidity data of the raw water intake in the mountainous area, and to determine the storm runoff state of the raw water based on the turbidity data. The sedimentation treatment module is used to divert the incoming water from the mountain raw water intake to the initial water collection tank when the influent turbidity data meets the initial rainstorm confluence conditions, and to temporarily sediment the initial high turbidity raw water through the initial water collection tank. The confluence buffer module is used to confluence and buffer the raw water in the mountainous area when the influent turbidity data meets the pretreatment influent conditions, and to discharge the initial sediments. The graded pretreatment module is used to sequentially perform coarse filtration, fine filtration and colloidal stabilization and destruction treatment on the raw water after the confluence buffer to complete the graded pretreatment. The dosing module is used to adjust the amount of chemicals added to the pre-treated raw water according to the turbidity detection results, so that the chemicals are mixed with the raw water. The sedimentation module is used to settle and clarify the raw water after the reagents are mixed and to remove sludge, so as to obtain pretreated effluent. The feedback control module is used to collect turbidity data during the confluence buffering, staged pretreatment, sedimentation and clarification, and sludge removal processes. Based on the turbidity data, the module adjusts the operating parameters during initial raw water diversion, backwashing, chemical dosing, stirring, or sludge discharge.

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