A method and system for efficient treatment and recycling of quartz sand processing wastewater

Abstract

The application discloses a kind of quartz sand processing wastewater efficient treatment and recycling method and system, it is related to wastewater treatment technical field;Collect the wastewater generated in quartz sand crushing, screening, washing process, remove large particle impurities by cyclone sand setting, grating filtration, into adjusting tank aeration stirring homogenization even amount;Composite coagulant and coagulant aid are sequentially added, after mixed flocculation, inclined tube precipitation solid-liquid separation;Supernatant is filtered by quartz sand and activated carbon multistage, and then is deeply oxidized by ozone process catalyzed by transition metal oxide ceramsite loading;Effluent is recycled according to the water quality requirement of production process, and tail water is discharged after disinfection;After sludge concentration conditioning of collection system, filter cake is disposed by pressure filtration, and filtrate is returned for treatment;On-line monitoring of each unit parameter and dynamic regulation and control operating condition are carried out.The application realizes wastewater efficient treatment by multistage combined process, composite coagulant dynamic dosing and quality recycling technology, to meet the wastewater treatment and resource demand of quartz sand processing industry.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a method and system for the efficient treatment and recycling of wastewater from quartz sand processing. Background Technology

[0002] Quartz sand is a crucial raw material in glass manufacturing, electronics, and building materials industries. Its processing involves multiple steps, including crushing, screening, and washing, generating substantial amounts of wastewater. This wastewater is primarily polluted by high concentrations of suspended solids, silt particles, and small amounts of residual mineral processing reagents and organic impurities, characterized by high suspended solids content, significant water quality fluctuations, and unstable flow rates. Direct discharge without effective treatment will cause water turbidity, river siltation, damage to aquatic ecosystems, and a significant waste of precious water resources. Traditional quartz sand processing wastewater treatment often employs simple natural sedimentation and sand filtration processes, which have limited effectiveness, making it difficult to consistently meet suspended solids concentration standards in the effluent. Furthermore, the sludge generated during treatment is often improperly disposed of, easily causing secondary pollution. With increasingly stringent national environmental standards and the worsening water shortage problem, traditional treatment processes can no longer meet the industry's needs, necessitating the development of efficient, stable, and recyclable wastewater treatment technologies.

[0003] Existing wastewater treatment processes for quartz sand processing have several shortcomings in practical applications. Most systems rely on manual experience to adjust coagulant dosage, failing to accurately control it based on real-time changes in influent water quality and quantity. This easily leads to problems such as overdosing and waste, or underdosing resulting in poor sedimentation. Inadequate design parameters for coagulation and sedimentation units, such as improper hydraulic retention time and surface load settings, hinder the effective settling of fine suspended solids, increasing the processing load on subsequent filtration units. Advanced treatment stages often employ a single filtration process, failing to remove residual dissolved organic matter and color from the wastewater, resulting in effluent quality that fails to meet high standards for reuse. Furthermore, most systems use a uniform effluent reuse method, without differentiating water supply based on the water quality requirements of different production processes, leading to the unreasonable use of water resources and a low recycling rate.

[0004] Existing wastewater treatment systems for quartz sand processing generally have low levels of automation and intelligence, lacking comprehensive online monitoring and intelligent control mechanisms. During system operation, the operating parameters of each treatment unit require manual adjustment, resulting in slow response times and an inability to promptly address sudden changes in water quality and quantity, easily leading to fluctuations in effluent quality. The sludge treatment process is weak, with poor sludge thickening and dewatering effects, resulting in high moisture content in the dewatered sludge cake, increasing the difficulty of sludge transportation and disposal. Some systems lack adequate emergency response facilities, making it impossible to take timely and effective measures when equipment malfunctions or water quality exceeds standards, potentially leading to excessive wastewater discharge. Furthermore, existing systems have low integration levels, lack coordination between treatment units, resulting in low overall operating efficiency, high operating and maintenance costs, and difficulty in meeting the demands of large-scale, continuous quartz sand processing production. Summary of the Invention

[0005] The present invention proposes a method and system for efficient treatment and recycling of quartz sand processing wastewater to solve the problems mentioned in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for efficient treatment and recycling of quartz sand processing wastewater, comprising the following steps: The production wastewater generated from the crushing, screening and washing of quartz sand is collected and transported to the pretreatment unit for cyclone sand settling and grid filtration. The effluent enters the equalization tank for homogenization and quantity adjustment. An aeration and stirring device is installed in the equalization tank to prevent the sedimentation of suspended solids. The effluent from the equalization tank is transported to the coagulation and sedimentation unit, where composite coagulant and coagulant aid are added in sequence. After rapid mixing and slow flocculation, the effluent enters the inclined tube sedimentation tank for solid-liquid separation, removing most of the suspended solids and colloidal substances from the wastewater. The water effluent from the intermediate water tank is transported to the multi-media filtration unit, where it undergoes deep filtration through a quartz sand filter tank and an activated carbon filter tank in sequence. The filtered water then enters the deep oxidation unit. The filtered water is treated with ozone catalytic oxidation process. Ceramsite loaded with transition metal oxides is used as a catalyst. Ozone and wastewater react countercurrently in the catalytic reaction tower to oxidize and decompose the recalcitrant organic pollutants and residual agents in the wastewater, while removing color and odor. The effluent from the deep treatment is transported to the reuse water tank and reused according to the water quality requirements of different production processes. The effluent that meets the standards but is not reused is discharged after disinfection. Sludge generated from coagulation sedimentation tank and filtration unit is collected, transported to sludge thickening tank for gravity thickening, and then conditioned with a conditioning agent. After thickening, the sludge is dewatered by plate and frame filter press until the moisture content meets the requirements. The sludge cake is transported off-site for disposal, and the filtrate is returned to the equalization tank for reprocessing. The system monitors the influent and effluent water quality parameters and operating parameters of each treatment unit online, and dynamically adjusts the operating conditions and reagent dosage of each unit based on the monitoring data.

[0007] Furthermore, it also includes a step for optimizing the dynamic dosage of composite coagulants. ; This refers to the dosage of the composite coagulant. Basic addition coefficient; This represents the concentration of suspended solids in the influent. This represents the wastewater treatment flow rate. pH influence coefficient; The pH value of the influent; This is the temperature influence coefficient; This refers to the inlet water temperature. This is the turbidity correction factor; It is the ratio of influent turbidity to suspended solids concentration.

[0008] Furthermore, it also includes a step for dynamic adjustment of the recycling rate of different types of waste. ;in The total system reuse rate; This represents the total water consumption for the production process. This is the water quality compliance rate coefficient; This refers to the processing capacity margin coefficient. This represents the total volume of water treated by the wastewater treatment system.

[0009] Furthermore, the pretreatment step specifically involves the wastewater first passing through a coarse screen to remove floating debris and large pieces of mud and sand with a particle size greater than 10mm, and then entering a vortex grit chamber. Sand particles with a particle size greater than 0.2mm are removed by centrifugal force separation. The grit is periodically discharged by a sand discharge pump. The effluent from the vortex grit chamber passes through a fine screen to remove fine debris with a particle size greater than 3mm. The fine screen adopts an automatic slag removal method, and the slag removal cycle is automatically adjusted according to the impurity content of the influent. The effluent enters an equalization tank, and the effective volume of the equalization tank is set according to the design treatment capacity of 6 to 8 hours. Perforated aeration pipes are installed in the tank for intermittent aeration and stirring.

[0010] Furthermore, the coagulation and sedimentation step specifically involves the following steps: effluent from the equalization tank is pumped to the mixing tank, where a composite coagulant consisting of polyaluminum chloride and polyferric sulfate in a 3:1 mass ratio is added. The mixing tank is mechanically stirred. The resulting effluent then enters the flocculation tank, where anionic polyacrylamide is added as a coagulant aid. The flocculation tank employs a folded plate flocculation structure, divided into three stages, with a total hydraulic retention time set to 15 to 20 minutes. The flocculated effluent then enters an inclined tube sedimentation tank, with a surface loading rate set to 1.5 to 2.0. The inclined tube is set at an angle of 60 degrees and the aperture is set at 50 mm. A sludge hopper is installed at the bottom of the sedimentation tank for regular sludge removal.

[0011] Furthermore, the multi-stage filtration and deep oxidation steps specifically involve the intermediate water tank effluent being pumped to a quartz sand filter tank using a pressurized pump. The filter media is refined quartz sand with a particle size of 0.5 to 1.0 mm. The backwashing cycle is set to 24 to 48 hours, and the backwashing intensity is set to 15 to 18. The backwashing time is set to 5 to 8 minutes. The effluent from the quartz sand filtration enters the activated carbon filter tank. The filter media is granular activated carbon with an iodine value greater than 800 mg / g. The filtration speed is set to 6 to 8 m / h. The backwashing cycle is set to 7 to 15 days. The effluent from the activated carbon filtration enters the ozone catalytic oxidation tower. The catalyst is ceramic granules loaded with copper oxide and manganese oxide. The filling height is set to 2000 to 2500 mm. The ozone dosage is set to 30 to 50 mg / L. The gas-water ratio is set to 1:1 to 1.5:1. The hydraulic retention time is set to 30 to 45 minutes. An ozone tail gas destruction device is installed at the top of the reaction tower.

[0012] Furthermore, the sludge treatment and online monitoring steps are as follows: the sludge generated by the coagulation sedimentation tank and the filtration unit enters the sludge thickening tank by gravity flow, the supernatant is returned to the equalization tank, and the sludge moisture content is reduced to 95% to 97% after thickening. It is then transported to the sludge conditioning tank, where polyaluminum chloride and lime are added as conditioning agents at 2% to 3% and 5% to 8% of the dry sludge mass, respectively. After stirring and mixing for 15 to 20 minutes, it is transported to the plate and frame filter press, and the filtration time is set to 2 to 3 hours. After dewatering, the moisture content of the sludge cake is reduced to below 60%. The online monitoring system sets monitoring points in the equalization tank, the effluent from the coagulation sedimentation tank, the effluent from the filtration tank, the effluent from the deep oxidation tank, and the reclaimed water tank to monitor parameters such as pH, suspended solids, turbidity, chemical oxygen demand, and flow rate in real time. The monitoring data is transmitted to the central controller.

[0013] Furthermore, it includes the following units: The wastewater collection and pretreatment unit is connected to the wastewater discharge outlets of each production process through pipelines, and is equipped with coarse screens, vortex grit chambers, fine screens and equalization tanks in sequence. The coagulation and sedimentation treatment unit is connected to the equalization tank via a booster pump, and is sequentially equipped with a mixing tank, a flocculation tank, and an inclined tube sedimentation tank. The multi-stage filtration unit is connected to the inclined tube sedimentation tank via an intermediate water tank, and quartz sand filter tank and activated carbon filter tank are set in sequence. The deep oxidation treatment unit is connected to the multi-stage filtration treatment unit and is equipped with an ozone generator, a catalytic reaction tower and an ozone exhaust gas destroyer. The recycling and distribution unit is connected to the deep oxidation treatment unit and is equipped with a reclaimed water tank, a separate water supply network, and a disinfection device. The sludge dewatering treatment unit is connected to the coagulation sedimentation treatment unit and the multi-stage filtration treatment unit, and is sequentially equipped with a sludge thickening tank, a sludge conditioning tank and a plate and frame filter press. The intelligent monitoring and control unit is connected to the sensors and actuators of each processing unit, and is equipped with a central controller, online monitoring instruments and communication modules.

[0014] Furthermore, the intelligent monitoring and control unit specifically includes pH sensors, suspended solids sensors, turbidity sensors, chemical oxygen demand sensors, and electromagnetic flow meters installed at key nodes of each processing unit. All sensors are connected to the central controller via a 485 bus. The central controller is a programmable logic controller with built-in coagulant dosage optimization algorithms and recycling rate control algorithms. It can automatically calculate and adjust the dosage of coagulant, flocculant aid, and ozone based on real-time monitoring data, while controlling the operating status of each pump, valve, and mixing equipment. The system has a human-machine interface that displays the operating parameters and water quality data of each unit in real time, and has abnormal alarm and fault self-diagnosis functions.

[0015] Furthermore, the recycling and distribution unit specifically comprises a primary recycling tank and a secondary recycling tank. The primary recycling tank is connected to the quartz sand washing process via pipelines, while the secondary recycling tank is connected to the crushing, screening, and floor washing processes via pipelines. The effluent from the deep treatment process first enters the primary recycling tank. When the water level in the primary recycling tank reaches the set upper limit, the excess effluent overflows into the secondary recycling tank. The secondary recycling tank is equipped with a disinfection device that uses sodium hypochlorite for disinfection at a dosage of 5 to 10 mg / L. Online water quality monitoring instruments and electric regulating valves are installed on each recycling pipeline. When the quality of the recycled water does not meet the requirements of the corresponding process, the system automatically switches to tap water supply and returns the substandard water to the regulating tank for reprocessing. The system is also equipped with an emergency water supply pipeline.

[0016] Compared with existing technologies, the beneficial effects of this invention are: This invention employs a combined process of pretreatment, coagulation sedimentation, multi-stage filtration, and ozone catalytic oxidation to form a complete wastewater treatment chain. This effectively removes various pollutants, including suspended solids, colloidal substances, and dissolved organic matter, from quartz sand processing wastewater, ensuring stable and compliant effluent quality. The pretreatment unit uses a combination of cyclone grit removal and bar filtration to remove impurities of different particle sizes in stages, effectively reducing the load on subsequent treatment units. The equalization tank's homogenization and flow regulation buffers fluctuations in water quality and quantity, ensuring stable operation of subsequent treatment processes.

[0017] This invention employs a composite coagulant and dynamic dosage optimization technology, adjusting the coagulant dosage in real time based on parameters such as influent water quality, quantity, temperature, and pH value. This ensures effective coagulation and sedimentation while avoiding unnecessary reagent consumption. The process design combining folded plate flocculation and inclined tube sedimentation enhances flocculation and solid-liquid separation, effectively removing most suspended solids and colloidal substances from wastewater. The multi-stage filtration unit uses a combination of quartz sand and activated carbon to further remove residual fine suspended solids and some dissolved organic matter, laying a solid foundation for subsequent advanced treatment.

[0018] This invention employs an ozone catalytic oxidation process using ceramic particles loaded with transition metal oxides as a catalyst. This process improves ozone utilization efficiency and oxidation capacity, effectively decomposing recalcitrant organic pollutants in wastewater while removing color and odor, thus enhancing effluent quality. The separate recycling technology, based on the water quality requirements of different production processes, reuses the treated wastewater in processes such as quartz sand washing, crushing and screening, and floor washing, thereby improving water resource recycling rates and reducing fresh water consumption.

[0019] The sludge treatment unit of this invention employs a combination of gravity thickening, conditioning, and plate and frame filtration, effectively reducing the sludge moisture content, facilitating sludge transportation and disposal. The filtrate from the filtration process is returned to the equalization tank for reprocessing, preventing secondary pollution. The intelligent monitoring and control unit collects real-time operating parameters and water quality data from each treatment unit via online monitoring instruments, automatically adjusting the operating conditions and reagent dosage of each unit to achieve intelligent control of the wastewater treatment process, reducing manual intervention and improving the stability and reliability of the system. The system is equipped with comprehensive emergency response facilities to effectively handle various emergencies, ensuring the continuous and stable operation of the wastewater treatment system and meeting the wastewater treatment and recycling needs of the quartz sand processing industry. Attached Figure Description

[0020] Figure 1 This is a schematic block diagram of a method for efficient treatment and recycling of quartz sand processing wastewater proposed in this invention. Figure 2 This is a schematic block diagram of the pretreatment and coagulation sedimentation process proposed in this invention; Figure 3 This is a flowchart of the deep purification and fractional reuse process proposed in this invention; Figure 4 This is a flowchart of the sludge reduction and resource utilization process proposed in this invention. Figure 5 This is a diagram of the intelligent monitoring and dynamic control architecture proposed in this invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Reference Figures 1 to 5 A method for efficient treatment and recycling of wastewater from quartz sand processing includes the following steps: The production wastewater generated from the crushing, screening and washing of quartz sand is collected and transported to the pretreatment unit for cyclone sedimentation and grid filtration to remove large particles of mud and sand and floating debris. The effluent enters the equalization tank for homogenization and quantity adjustment. An aeration and stirring device is installed in the equalization tank to prevent the sedimentation of suspended solids. The effluent from the equalization tank is transported to the coagulation and sedimentation unit, where composite coagulant and coagulant aid are added in sequence. After rapid mixing and slow flocculation, the effluent enters the inclined tube sedimentation tank for solid-liquid separation, removing most of the suspended solids and colloidal substances in the wastewater. The supernatant of the sedimentation tank overflows into the intermediate water tank. The water effluent from the intermediate water tank is transported to the multi-media filtration unit, where it undergoes deep filtration through a quartz sand filter tank and an activated carbon filter tank in sequence to remove residual fine suspended solids and some dissolved organic matter. The filtered water then enters the deep oxidation unit. The filtered water is treated with ozone catalytic oxidation process. The catalyst is ceramic particles loaded with transition metal oxides. Ozone and wastewater react countercurrently in the catalytic reaction tower to oxidize and decompose the recalcitrant organic pollutants and residual agents in the wastewater, while removing color and odor. The effluent from the deep treatment is transported to the reuse water tank and reused according to the water quality requirements of different production processes. The effluent that meets the standards but is not reused is discharged after disinfection. The reuse water tank is equipped with an overflow pipe and an emergency discharge pipe. Sludge generated from coagulation sedimentation tank and filtration unit is collected, transported to sludge thickening tank for gravity thickening, and then conditioned with a conditioning agent. After thickening, the sludge is dewatered by plate and frame filter press until the moisture content meets the requirements. The sludge cake is transported off-site for disposal, and the filtrate is returned to the equalization tank for reprocessing. The system monitors the influent and effluent water quality parameters and operating parameters of each treatment unit online, and dynamically adjusts the operating conditions and reagent dosage of each unit based on the monitoring data, thereby achieving intelligent control and stable operation of the wastewater treatment process.

[0023] This invention also includes a step for optimizing the dynamic dosage of the composite coagulant. ; This refers to the dosage of the composite coagulant, expressed in mg / L. The basic dosage coefficient is expressed in mg / L and ranges from 0.012 to 0.018. The value represents the concentration of suspended solids in the influent, in mg / L. This represents the wastewater treatment flow rate, in m³ / h. The pH influence coefficient is dimensionless and ranges from 0.12 to 0.18. The pH value of the influent is dimensionless. This is the temperature influence coefficient, dimensionless, with a value ranging from 0.008 to 0.012; This is the inlet water temperature value, in °C. This is the turbidity correction factor, dimensionless, with a value ranging from 0.003 to 0.005; The ratio of influent turbidity to suspended solids concentration is dimensionless. By incorporating suspended solids concentration, flow rate, and temperature into the calculation, and taking into account the interaction between water quality, water quantity, and environmental conditions while ensuring dimensional consistency, the coagulant dosage can be precisely and dynamically adjusted, thus reducing chemical consumption while ensuring sedimentation effect.

[0024] This invention also includes a step for dynamic adjustment of the recycling rate of different materials. ;in The total system reuse rate is expressed as % This represents the total water consumption for the production process, expressed in units of... ; is the water quality compliance rate coefficient, which is dimensionless and ranges from 0 to 1. It is taken as 1 when the water quality of the effluent from the deep treatment meets the reuse requirements. This is the capacity margin coefficient, dimensionless, with a value ranging from 0.85 to 0.95; The total volume of wastewater treated by the system is expressed in units of [unit missing]. The reuse ratio is adjusted in real time based on the production water demand and the operating status of the treatment system to balance the water resource utilization rate and the treatment system load, ensuring a continuous and stable supply of production water.

[0025] In this invention, the pretreatment step specifically involves the wastewater first passing through a coarse screen to remove floating debris and large pieces of silt larger than 10 mm, and then entering a vortex grit chamber. The hydraulic retention time of the vortex grit chamber is set to 15 to 20 minutes, and the surface loading is set to 20 to 25. The system uses centrifugal force to separate and remove sand particles larger than 0.2mm. The settled sand is periodically discharged via a sand discharge pump. The effluent from the cyclone grit chamber passes through a fine screen to remove fine debris larger than 3mm. The fine screen uses an automatic cleaning system, with the cleaning cycle automatically adjusted according to the impurity content of the influent. The effluent then enters a regulating tank. The effective volume of the regulating tank is set to handle 6 to 8 hours of water. Perforated aeration pipes are installed in the tank for intermittent aeration and mixing, with an aeration intensity set to 2 to 3. To prevent the deposition of suspended matter.

[0026] In this invention, the coagulation and sedimentation step specifically involves the following steps: effluent from the equalization tank is pumped to a mixing tank, where a composite coagulant composed of polyaluminum chloride and polyferric sulfate in a 3:1 mass ratio is added. The mixing tank is mechanically stirred at a speed of 200-300 r / min, with a hydraulic retention time of 2-3 minutes. The effluent after mixing enters a flocculation tank where anionic polyacrylamide is added as a coagulant aid. The flocculation tank employs a folded plate flocculation structure, divided into three stages: the first stage has a stirring speed of 100-150 r / min, the second stage 50-80 r / min, and the third stage 20-30 r / min, with a total hydraulic retention time of 15-20 minutes. The effluent after flocculation enters an inclined tube sedimentation tank, with a surface loading of 1.5-2.0. The hydraulic retention time is set to 1.5 to 2 hours, the inclination angle of the inclined tube is set to 60 degrees, the aperture is set to 50 mm, a sludge hopper is installed at the bottom of the sedimentation tank, the inclination angle of the sludge hopper is set to 60 degrees, and sludge is discharged regularly, with a sludge discharge cycle of 4 to 6 hours.

[0027] In this invention, the multi-stage filtration and deep oxidation steps specifically involve the following: effluent from the intermediate water tank is pumped to a quartz sand filter tank via a pressurized pump. The filter media is refined quartz sand with a particle size of 0.5 to 1.0 mm. The filter layer thickness is set to 800 to 1000 mm, the filtration speed is set to 8 to 10 m / h, the backwashing cycle is set to 24 to 48 hours, and the backwashing intensity is set to 15 to 18. The backwashing time is set to 5 to 8 minutes. The effluent from the quartz sand filtration enters the activated carbon filter tank. The filter media is granular activated carbon with an iodine value greater than 800 mg / g. The filter layer thickness is set to 600 to 800 mm, the filtration speed is set to 6 to 8 m / h, and the backwashing cycle is set to 7 to 15 days. The effluent from the activated carbon filtration enters the ozone catalytic oxidation tower. The catalyst is ceramic granules loaded with copper oxide and manganese oxide with a particle size of 3 to 5 mm. The filling height is set to 2000 to 2500 mm, the ozone dosage is set to 30 to 50 mg / L, the gas-water ratio is set to 1:1 to 1.5:1, and the hydraulic retention time is set to 30 to 45 minutes. An ozone tail gas destruction device is installed at the top of the reaction tower.

[0028] In this invention, the sludge treatment and online monitoring steps are as follows: sludge generated by the coagulation sedimentation tank and the filtration unit enters the sludge thickening tank by gravity flow. The hydraulic retention time in the thickening tank is set to 12 to 24 hours. The supernatant is returned to the equalization tank. After thickening, the sludge moisture content drops to 95% to 97%, and it is transported to the sludge conditioning tank. Polyaluminum chloride and lime are added as conditioning agents, with addition amounts of 2% to 3% and 5% to 8% of the dry sludge mass, respectively. After stirring and mixing for 15 to 20 minutes, it is transported to a plate and frame filter press. The filter pressure is set to 0.6 to 0.8 MPa, and the filter time is set to 2 to 3 hours. After dewatering, the sludge cake moisture content drops to below 60%. The online monitoring system sets monitoring points in the equalization tank, the effluent from the coagulation sedimentation tank, the effluent from the filtration tank, the effluent from the deep oxidation tank, and the reclaimed water tank to monitor parameters such as pH, suspended solids, turbidity, chemical oxygen demand, and flow rate in real time. The monitoring data is transmitted to the central controller, which automatically adjusts the frequency of the reagent dosing pump, the valve opening, and the equipment operating status according to preset logic.

[0029] This invention includes the following units: The wastewater collection and pretreatment unit is connected to the wastewater discharge outlets of each production process through pipelines. It is equipped with coarse screens, vortex grit chambers, fine screens and equalization tanks in sequence to remove large particulate impurities and equalize the quality and quantity of wastewater. The coagulation and sedimentation treatment unit is connected to the equalization tank via a booster pump, and is equipped with a mixing tank, a flocculation tank and an inclined tube sedimentation tank in sequence for adding reagents to carry out coagulation reaction and solid-liquid separation. The multi-stage filtration unit is connected to the inclined tube sedimentation tank through an intermediate water tank, and is equipped with quartz sand filter tank and activated carbon filter tank in sequence to remove residual suspended solids and some organic matter. The deep oxidation treatment unit is connected to the multi-stage filtration treatment unit and is equipped with an ozone generator, a catalytic reaction tower and an ozone exhaust gas destroyer for oxidizing and decomposing recalcitrant organic pollutants. The recycling and distribution unit is connected to the deep oxidation treatment unit and is equipped with a reclaimed water tank, a separate water supply network, and a disinfection device to reuse treated wastewater according to production needs. The sludge dewatering treatment unit is connected to the coagulation sedimentation treatment unit and the multi-stage filtration treatment unit. It is equipped with a sludge thickening tank, a sludge conditioning tank and a plate and frame filter press in sequence to treat the sludge generated by the system. The intelligent monitoring and control unit is connected to the sensors and actuators of each processing unit, and is equipped with a central controller, online monitoring instruments and communication modules to realize real-time monitoring and intelligent control of the system's operating status.

[0030] In this invention, the intelligent monitoring and control unit specifically includes pH sensors, suspended solids sensors, turbidity sensors, chemical oxygen demand sensors, and electromagnetic flow meters installed at key nodes of each processing unit. All sensors are connected to the central controller via a 485 bus. The central controller is a programmable logic controller with built-in coagulant dosage optimization algorithms and recycling rate control algorithms. It can automatically calculate and adjust the dosage of coagulant, flocculant aid, and ozone based on real-time monitoring data, while controlling the operating status of each pump, valve, and mixing device. The system has a human-machine interface that displays the operating parameters and water quality data of each unit in real time, supports switching between manual and automatic control modes, and has abnormal alarm and fault self-diagnosis functions. When water quality exceeds the standard or equipment failure is detected, it automatically issues an audible and visual alarm and records the alarm information.

[0031] In this invention, the recycling and distribution unit specifically comprises a primary recycling tank and a secondary recycling tank. The primary recycling tank is connected to the quartz sand washing process via pipelines, while the secondary recycling tank is connected to the crushing, screening, and floor washing processes via pipelines. The effluent from the deep treatment process first enters the primary recycling tank. When the water level in the primary recycling tank reaches the set upper limit, the excess effluent overflows into the secondary recycling tank. The secondary recycling tank is equipped with a disinfection device using sodium hypochlorite at a dosage of 5 to 10 mg / L and a contact time of no less than 30 minutes. Online water quality monitoring instruments and electric regulating valves are installed on each recycling water pipeline. When the recycled water quality does not meet the requirements of the corresponding process, the system automatically switches to tap water supply and returns the substandard water to the regulating tank for reprocessing. The system is equipped with an emergency water supply pipeline to ensure a continuous supply of production water.

[0032] The following two examples further illustrate the specific implementation of this system: The present invention discloses a method and system for the efficient treatment and recycling of quartz sand processing wastewater. This system employs a combined process of pretreatment, coagulation sedimentation, multi-stage filtration, ozone catalytic oxidation, and fractional recycling, combined with intelligent monitoring and dynamic control technology, to achieve efficient treatment and resource utilization of quartz sand processing wastewater. Addressing the characteristics of high suspended solids content and large water quality fluctuations in quartz sand processing wastewater, the system optimizes the operating parameters of each treatment unit and utilizes dynamic addition of composite coagulants and fractional recycling technology to ensure stable effluent quality while improving water resource recycling rates. The invention is further described in detail below through two specific embodiments. Example

[0033] This embodiment is applied to a large-scale quartz sand mining and processing plant. The wastewater mainly comes from the crushing, screening, and washing processes. The designed treatment capacity is 500 cubic meters per hour. The concentration of suspended solids in the influent fluctuates greatly and contains a small amount of mud and sand particles and residual dust removal agents. The system adopts a centralized deployment, with each treatment unit arranged sequentially according to the process flow and connected to the wastewater discharge outlet of the production workshop through a dedicated pipeline.

[0034] During the pretreatment unit operation phase, production wastewater is collected by gravity into a wastewater collection channel. First, it passes through a coarse screen to remove large floating debris and solid impurities larger than 10mm, such as branches, woven bags, and stones. The coarse screen is a mechanical screen with a bar spacing of 10mm. The cleaning cycle is automatically adjusted according to the impurity content of the influent. The cleaning program is automatically activated when the pressure difference across the screen exceeds a set value. The wastewater then enters a cyclone grit chamber, where centrifugal force generated by the hydrocyclone separates and removes sand particles larger than 0.2mm. The hydraulic retention time of the cyclone grit chamber is set to 18 minutes, and the surface loading rate is set to 22 cubic meters per square meter per hour. The settled grit is periodically discharged by a sand pump at the bottom of the chamber and sent to the plant's sand yard for cleaning and recycling.

[0035] The effluent from the cyclone grit chamber is passed through a fine screen to remove fine debris larger than 3mm. The screen bars are spaced 3mm apart and an automatic cleaning system is used, with a cleaning cycle of 2 hours. The effluent then enters a regulating tank for homogenization and flow equalization. The effective volume of the regulating tank is set according to the design capacity of 8 hours of water treatment. Perforated aeration pipes are installed in the tank, using intermittent aeration and stirring, aerating once every 2 hours for 15 minutes each time, with an aeration intensity set at 2.5 cubic meters per square meter per hour to prevent suspended solids from settling at the bottom. The regulating tank is equipped with level sensors, pH sensors, and flow sensors. Based on the level, the number of operating booster pumps is automatically controlled to ensure a stable influent flow rate to subsequent treatment units.

[0036] During the operation of the coagulation and sedimentation treatment unit, the effluent from the equalization tank is pumped to the mixing tank, where a composite coagulant consisting of polyaluminum chloride and polyferric sulfate in a 3:1 mass ratio is added. The mixing tank uses a vertical mechanical agitator with a stirring speed of 250 rpm and a hydraulic retention time of 2.5 minutes to ensure rapid and thorough mixing of the coagulant and wastewater. The mixed effluent then enters a three-stage flocculation tank. The first stage has a stirring speed of 120 rpm, the second stage 60 rpm, and the third stage 25 rpm, with a total hydraulic retention time of 18 minutes. By gradually reducing the stirring speed at each stage, the fine flocs are encouraged to gradually aggregate into large, dense flocs.

[0037] After flocculation, the effluent enters an inclined tube sedimentation tank. The surface loading rate of the sedimentation tank is set to 1.8 cubic meters per square meter per hour, the hydraulic retention time is set to 1.8 hours, the inclination angle of the inclined tubes is set to 60 degrees, and the orifice diameter is set to 50 mm. A sludge interface meter is installed in the sedimentation tank to monitor the sludge layer height in real time. When the sludge interface reaches the set height, the sludge discharge pump is automatically activated to discharge the bottom sludge to the sludge thickening tank. The sludge discharge cycle is set to 5 hours. The supernatant from the sedimentation tank flows by gravity to the intermediate water tank through an overflow weir.

[0038] During the operation of the multi-stage filtration and deep oxidation treatment unit, the effluent from the intermediate water tank is pumped to the quartz sand filter tank via a booster pump. Two filter tanks operate in parallel, one in use and one on standby. The filter media is refined quartz sand with a particle size of 0.5 to 1.0 mm, the filter layer thickness is set to 900 mm, and the filtration velocity is set to 9 meters per hour. Differential pressure sensors are installed at the inlet and outlet of the filter tank. Backwashing is automatically initiated when the inlet-outlet pressure difference exceeds 0.05 MPa or reaches the 48-hour timed backwash cycle. Backwashing employs a combined air-water backwashing method, first air-washing for 3 minutes, then water-washing for 6 minutes, with a backwash intensity set to 16 liters per square meter per second. The backwash wastewater is returned to the equalization tank for retreatment.

[0039] The effluent from the quartz sand filtration enters an activated carbon filter tank. The filter media uses granular activated carbon with an iodine value greater than 800 mg / g, with a filter bed thickness of 700 mm, a filtration velocity of 7 meters per hour, and a backwashing cycle of 10 days. The activated carbon filtration effluent then enters an ozone catalytic oxidation tower. Ozone is generated by an ozone generator using pure oxygen as the gas source, with an ozone dosage of 40 mg / L and a gas-to-water ratio of 1.2:1. The catalyst is ceramic granules loaded with copper oxide and manganese oxide, with a particle size of 3 to 5 mm and a filling height of 2200 mm. Ozone and wastewater react countercurrently within the tower, with a hydraulic residence time of 35 minutes, oxidizing and decomposing residual organic reagents and color substances in the wastewater. An ozone tail gas destruction device is installed at the top of the reaction tower, using a thermal decomposition method to treat the tail gas at a heating temperature of 250℃, ensuring that the ozone concentration in the tail gas meets the emission standards before discharge.

[0040] During the operation of the recycling and sludge treatment unit, the effluent from the advanced treatment process is transported to the reuse water tank via pipelines. The reuse water tank is divided into a primary reuse water tank and a secondary reuse water tank. The primary reuse water tank is connected to the quartz sand washing process via dedicated pipelines, while the secondary reuse water tank is connected to the crushing, screening, and workshop floor washing processes via pipelines. The advanced treatment effluent first enters the primary reuse water tank. When the water level in the primary reuse water tank reaches the set upper limit, the excess effluent flows by gravity to the secondary reuse water tank through the overflow pipe. The secondary reuse water tank is equipped with a sodium hypochlorite disinfection device, with a dosage set at 7 mg / L and a contact time of no less than 30 minutes, to prevent the growth of microorganisms in the reused water. Online suspended solids and turbidity sensors are installed on each reuse water pipeline. When the reused water quality does not meet the requirements of the corresponding process, the reuse water electric valve is automatically closed, the tap water supply valve is opened, and the substandard water is transported to the equalization tank for retreatment through the return pipe.

[0041] The sludge generated by the system first enters a sludge thickening tank for gravity thickening. The hydraulic retention time in the thickening tank is set to 18 hours, and the supernatant is returned to the equalization tank through an overflow pipe. After thickening, the sludge moisture content is reduced to 96%, and it is then pumped to a sludge conditioning tank via a screw pump. Polyaluminum chloride and lime are added as conditioning agents at dosages of 2.5% and 6% of the dry sludge mass, respectively. After mixing for 18 minutes, the mixture is conveyed to a plate and frame filter press. The filter press pressure is set to 0.7 MPa, and the filter press time is set to 2.5 hours. After dewatering, the sludge cake moisture content is reduced to below 60%, and it is transported to a sludge cake storage area via a belt conveyor, and periodically transported to a compliant disposal site. The filtrate from the filter press is returned to the equalization tank for reprocessing via pipeline.

[0042] During the operation of the intelligent monitoring and control unit, online monitoring points are set up at the effluent from the equalization tank, coagulation sedimentation tank, quartz sand filtration tank, activated carbon filtration tank, ozone catalytic oxidation tank, and reclaimed water tank. pH sensors, suspended solids sensors, turbidity sensors, chemical oxygen demand (COD) sensors, and electromagnetic flow meters are installed. All sensors are connected to the central controller via a 485 bus. The central controller is a programmable logic controller (PLC) with built-in algorithms for coagulant dosage optimization and recycling rate control. The system collects water quality and operating parameters from each monitoring point every 5 minutes, automatically calculates the optimal dosage of composite coagulant, coagulant aid, and ozone, and achieves precise dosing by adjusting the frequency of the metering pumps. Simultaneously, it automatically controls the operating status of each pump, valve, mixing equipment, and ozone generator, dynamically adjusting the recycling ratio based on the reclaimed water tank level and production water demand. The system features a human-machine interface that displays real-time operating parameters, water quality data, and equipment status for each unit, supporting switching between manual and automatic control modes. It has abnormal alarm and fault self-diagnosis functions. When the effluent water quality exceeds the standard or the equipment is operating abnormally, it will automatically issue an audible and visual alarm, record the alarm information, and start the emergency handling procedure to return the wastewater to the equalization tank for reprocessing.

[0043] This embodiment addresses the challenges of large-scale wastewater treatment and significant water quality fluctuations in large-scale quartz sand mining and processing plants. It employs an optimized multi-stage combined treatment process to achieve efficient wastewater treatment and stable compliance with standards. The dynamic dosing technology for composite coagulants adjusts the dosage in real-time based on influent water quality, quantity, and environmental conditions, ensuring effective coagulation and sedimentation while avoiding waste. The differentiated recycling system rationally allocates water resources according to the water requirements of different production processes, improving water resource recycling rates. The intelligent monitoring and control unit enables fully automated operation of the treatment process, reducing manual intervention and enhancing system stability and reliability, thus meeting the wastewater treatment needs of large-scale continuous quartz sand processing. Example

[0044] This embodiment is applied to a deep-processing enterprise of quartz sand for glass production. The wastewater mainly comes from the selection, pickling, and washing processes of quartz sand. The designed treatment capacity is 100 cubic meters per hour. In addition to high concentrations of suspended solids, the influent also contains a small amount of residual flotation reagents and pickling solution, requiring high quality reclaimed water that meets the cleaning standards for quartz sand used in glass production. The system adopts a modular deployment, with each treatment unit integrated into a single unit, facilitating installation and maintenance, and seamlessly connecting with the wastewater discharge system of the production workshop.

[0045] During the pretreatment unit operation phase, wastewater from each production process is collected through underground pipelines to the plant's wastewater collection station. First, it passes through a coarse screen to remove debris and waste rock larger than 10mm. The coarse screen is manually cleaned twice daily. The wastewater then enters a cyclone grit chamber with a hydraulic retention time of 15 minutes and a surface loading rate of 20 cubic meters per square meter per hour. Centrifugal separation removes quartz sand particles larger than 0.2mm. The grit is discharged daily, cleaned, and returned to the production process for reuse. The effluent from the cyclone grit chamber passes through a fine screen to remove fine debris larger than 3mm. The fine screen is automatically cleaned every 4 hours. The effluent then enters a regulating tank for homogenization and flow equalization. The regulating tank's effective volume is designed to handle 6 hours of wastewater. Perforated aeration pipes are installed in the tank, employing continuous low-intensity aeration at 2 cubic meters per square meter per hour. This prevents suspended solids from settling and also serves as pre-aeration, oxidizing some reducing substances. The equalization tank is equipped with an online pH monitor and an acid-base dosing device. When the pH of the influent exceeds the range of 6 to 9, sodium hydroxide or sulfuric acid is automatically added for neutralization and adjustment to ensure the stability of the influent pH of the subsequent coagulation and sedimentation unit.

[0046] During the operation of the coagulation and sedimentation treatment unit, the effluent from the equalization tank is pumped to the mixing tank, where a composite coagulant is added. The mixing tank's stirring speed is set to 200 rpm, and the hydraulic retention time is set to 2 minutes. The mixed effluent then enters the baffle flocculation tank, where the three-stage stirring speeds are set to 100 rpm, 50 rpm, and 20 rpm respectively, with a total hydraulic retention time of 15 minutes. The flocculated effluent then enters the inclined tube sedimentation tank, where the surface loading rate is set to 1.5 cubic meters per square meter per hour, the hydraulic retention time is set to 2 hours, the inclined tubes have an inclination angle of 60 degrees, and the orifice diameter is 50 mm. A sludge hopper is installed at the bottom of the sedimentation tank, with an inclination angle of 60 degrees and a sludge discharge cycle of 4 hours, periodically discharging sludge to the sludge thickening tank. The supernatant from the sedimentation tank flows by gravity to the intermediate water tank, which is equipped with a level sensor to control the influent flow rate to subsequent filtration units.

[0047] During the operation of the multi-stage filtration and deep oxidation treatment unit, the effluent from the intermediate water tank is pumped to a quartz sand filter tank. The filter media is refined quartz sand with a particle size of 0.5 to 1.0 mm, the filter bed thickness is set to 800 mm, and the filtration velocity is set to 8 meters per hour. The backwash cycle is set to 24 hours, the backwash intensity is set to 15 liters per square meter per second, and the backwash time is set to 5 minutes. The backwash wastewater is returned to the equalization tank. The effluent from the quartz sand filter enters an activated carbon filter tank. The filter media is granular activated carbon with an iodine value greater than 800 mg / g, the filter bed thickness is set to 800 mm, the filtration velocity is set to 6 meters per hour, and the backwash cycle is set to 7 days. The effluent from the activated carbon filter enters an ozone catalytic oxidation tower. The catalyst is ceramsite particles loaded with copper oxide and manganese oxide, and the filling height is set to 2500 mm. The ozone dosage is automatically adjusted based on the effluent chemical oxygen demand (COD) concentration, ranging from 30 to 50 mg / L. The gas-to-water ratio is set to 1:1, and the hydraulic retention time is set to 45 minutes. This effectively decomposes residual flotation reagents and other recalcitrant organic pollutants in the wastewater, removing color and odor. An ozone tail gas destruction device is installed at the top of the reaction tower, employing a combination of activated carbon adsorption and thermal decomposition to treat the tail gas, ensuring that emissions meet standards.

[0048] During the operation of the recycling and sludge treatment unit, the effluent from the advanced treatment enters the reuse water tank, which is divided into primary and secondary tanks. Primary reuse water is used for quartz sand selection and washing processes, requiring high levels of suspended solids and turbidity. Secondary reuse water is used for crushing, screening, and workshop floor washing. The advanced treatment effluent first enters the primary reuse water tank, overflowing into the secondary reuse water tank when the water level reaches its upper limit. The secondary reuse water tank is equipped with a sodium hypochlorite disinfection device, with a dosage of 5 mg / L and a contact time of 30 minutes. Online water quality monitoring instruments are installed on each reuse water pipeline to monitor water quality changes in real time, automatically switching water supply when the water quality does not meet requirements. The sludge generated by the system enters the sludge thickening tank, with a hydraulic retention time of 12 hours. The supernatant is returned to the equalization tank. After thickening, the sludge moisture content drops to 97%, and it is transported to the sludge conditioning tank, where polyaluminum chloride and lime are added as conditioning agents at 2% and 5% of the dry sludge mass, respectively. After mixing for 15 minutes, the mixture enters the plate and frame filter press. The filter press pressure was set to 0.6 MPa, the filter press time was set to 2 hours, and the moisture content of the dewatered sludge cake was less than 60%. It was transported to a compliant landfill for disposal, and the filter press filtrate was returned to the equalization tank.

[0049] During the operation of the intelligent monitoring and control unit, online monitoring instruments are installed at each key treatment node to collect water quality and operating parameters in real time. The central controller has a built-in optimization algorithm that dynamically adjusts the coagulant dosage, ozone dosage, and backwash cycle based on the influent water quality and volume. The system is equipped with an emergency treatment tank with an effective volume designed for 2 hours of water flow. In the event of equipment failure or severely substandard water quality, wastewater is automatically switched to the emergency treatment tank for temporary storage, and then treated in batches after the fault is resolved. The system supports remote monitoring, allowing managers to view the system's operating status in real time, receive alarm information, and remotely adjust operating parameters via mobile phone or computer. Simultaneously, the system automatically generates operating logs and water quality reports for convenient daily management and compliance inspections.

[0050] This embodiment addresses the challenges of wastewater from quartz sand deep-processing enterprises, which contains small amounts of organic reagents and requires high-quality reclaimed water. It enhances the deep oxidation treatment unit by employing a catalyst loaded with transition metal oxides to improve ozone oxidation efficiency, effectively removing recalcitrant organic pollutants and ensuring the effluent meets high-standard reuse requirements. The differentiated recycling system provides refined water supply based on the water quality needs of different processes, avoiding the inefficient use of water resources. Modular deployment and intelligent remote monitoring reduce system installation and maintenance costs, while the emergency treatment tank enhances the system's resilience, enabling it to meet the wastewater treatment and recycling needs of small and medium-sized quartz sand deep-processing enterprises.

[0051] Reference Figure 2 The article details the physical screening and chemical sedimentation processes at the front end of the wastewater treatment system. Raw wastewater, carrying a large amount of silt, enters the system and first undergoes two stages of physical interception via coarse and fine screens. Combined with an intermediate vortex grit chamber, the centrifugal force of the water flow efficiently removes floating debris and large particles of heavy sand. The preliminarily purified water flows into a regulating tank, where aeration devices at the bottom continuously agitate the water, both equalizing the water quality and quantity and preventing premature sedimentation of fine suspended solids. Subsequently, the water is pumped to the chemical reaction zone, where it undergoes a rapid and intense reaction with a composite coagulant in the mixing tank, breaking down colloidal stability. It then enters a multi-stage blister flocculation tank, where, with the help of a coagulant aid, slow stirring promotes the growth of tiny particles into dense, large flocs. Finally, the water gently flows over an inclined tube sedimentation tank, where dense inclined tube components accelerate solid-liquid separation. The clear supernatant overflows into the next process, while the sediment at the bottom is periodically removed.

[0052] Reference Figure 3This describes the deep purification mechanism of wastewater after initial sedimentation and the tiered water resource allocation logic. The clarified water in the intermediate tank still contains trace amounts of fine suspended solids and dissolved organic matter. It requires pump pressurization to sequentially penetrate refined quartz sand filter layers and granular activated carbon filter layers to complete physical interception and adsorption purification. The filtered water is then injected into an ozone catalytic oxidation reaction tower. Under the mediation of a specific ceramic catalyst, gaseous ozone and water flow in a counter-current manner to fully decompose residual reagents and stubborn organic matter, removing odors and color. The high-quality reclaimed water after deep treatment is first injected into the primary reuse water tank, prioritizing the quartz sand washing process, which has extremely stringent water quality requirements. When the primary tank overflows or has excess water, the water flows downstream to the secondary reuse water tank, where it undergoes appropriate disinfection treatment before being widely transported to the ore crushing dust suppression and workshop floor washing processes, which have moderate water quality requirements, thus maximizing the use of water resources.

[0053] Reference Figure 4 This system focuses on the reduction and harmless treatment of sludge, a byproduct generated during system operation. The liquid sludge produced in the sedimentation tank and filtration backwashing process has an extremely high water content and is first collected in the sludge thickening tank. Here, the sludge undergoes prolonged settling under its own gravity, significantly reducing its volume. The separated supernatant flows directly back to the system's starting point for reprocessing. The thickened sludge is then pumped into the sludge conditioning tank, where the system precisely and quantitatively adds polymers and alkaline conditioners. Mechanical stirring alters the surface tension and physical structure of the sludge particles, causing them to lose their water-holding capacity. The conditioned sludge is finally injected under high pressure into a plate and frame filter press. Under strong mechanical extrusion, the free water in the sludge is completely forced out, ultimately forming a dry sludge cake with extremely low water content and a hard texture. This facilitates safe transportation or utilization as building materials. The extruded filtrate is also returned to the system for recycling.

[0054] Reference Figure 5 This showcases the intelligent neural network architecture that drives the entire wastewater treatment system to operate efficiently and energy-savingly. The underlying layer of this architecture consists of probes distributed throughout the various pools and pipe networks, continuously collecting core parameters such as pH, suspended solids concentration, turbidity, and water flow rate in real time. These underlying physical quantities, along with the operating load status of the water pump motors, are synchronously uploaded to the central controller. The central controller is equipped with a dynamic logic processing module that can automatically calculate the optimal chemical dosage ratio based on fluctuations in influent water quality and current temperature conditions, and directly command the variable frequency dosing pumps to execute precisely, completely eliminating the need for traditional manual, experience-based, and blind dosing. Simultaneously, the controller can analyze the actual water demand of each production line and automatically schedule the electric valves of each level of the recycled water pool. Once the system detects abnormal water quality exceeding standards or mechanical overload, it will immediately disconnect related equipment, trigger a self-diagnostic protection mechanism, and display a high-level warning on the central control screen, ensuring unattended operation and safe and stable operation of the water facilities.

[0055] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for efficient treatment and recycling of wastewater from quartz sand processing, characterized in that, Includes the following steps: The production wastewater generated from the crushing, screening and washing of quartz sand is collected and transported to the pretreatment unit for cyclone sand settling and grid filtration. The effluent enters the equalization tank for homogenization and quantity adjustment. An aeration and stirring device is installed in the equalization tank to prevent the sedimentation of suspended solids. The effluent from the equalization tank is transported to the coagulation and sedimentation unit, where composite coagulant and coagulant aid are added in sequence. After rapid mixing and slow flocculation, the effluent enters the inclined tube sedimentation tank for solid-liquid separation, removing most of the suspended solids and colloidal substances from the wastewater. The water effluent from the intermediate water tank is transported to the multi-media filtration unit, where it undergoes deep filtration through a quartz sand filter tank and an activated carbon filter tank in sequence. The filtered water then enters the deep oxidation unit. The filtered water is treated with ozone catalytic oxidation process. Ceramsite loaded with transition metal oxides is used as a catalyst. Ozone and wastewater react countercurrently in the catalytic reaction tower to oxidize and decompose the recalcitrant organic pollutants and residual agents in the wastewater, while removing color and odor. The effluent from the deep treatment is transported to the reuse water tank and reused according to the water quality requirements of different production processes. The effluent that meets the standards but is not reused is discharged after disinfection. Sludge generated from coagulation sedimentation tank and filtration unit is collected, transported to sludge thickening tank for gravity thickening, and then conditioned with a conditioning agent. After thickening, the sludge is dewatered by plate and frame filter press until the moisture content meets the requirements. The sludge cake is transported off-site for disposal, and the filtrate is returned to the equalization tank for reprocessing. The system monitors the influent and effluent water quality parameters and operating parameters of each treatment unit online, and dynamically adjusts the operating conditions and reagent dosage of each unit based on the monitoring data.

2. The method for efficient treatment and recycling of quartz sand processing wastewater according to claim 1, characterized in that, It also includes a step for optimizing the dynamic dosage of composite coagulants. ; This refers to the dosage of the composite coagulant. Basic addition coefficient; This represents the concentration of suspended solids in the influent. This represents the wastewater treatment flow rate. pH influence coefficient; The pH value of the influent; This is the temperature influence coefficient; This refers to the inlet water temperature. This is the turbidity correction factor; It is the ratio of influent turbidity to suspended solids concentration.

3. The method for efficient treatment and recycling of quartz sand processing wastewater according to claim 1, characterized in that, It also includes a step for dynamic adjustment of the recycling rate of different types of waste. ;in The total system reuse rate; This represents the total water consumption for the production process. This is the water quality compliance rate coefficient; This refers to the processing capacity margin coefficient. This represents the total volume of water treated by the wastewater treatment system.

4. The method for efficient treatment and recycling of quartz sand processing wastewater according to claim 1, characterized in that, The pretreatment steps are as follows: the wastewater first passes through a coarse screen to remove floating debris and large pieces of mud and sand with a particle size greater than 10mm, and then enters a vortex grit chamber. Sand particles with a particle size greater than 0.2mm are removed by centrifugal force separation. The grit is periodically discharged by a sand discharge pump. The effluent from the vortex grit chamber passes through a fine screen to remove fine debris with a particle size greater than 3mm. The fine screen adopts an automatic sludge removal method, and the sludge removal cycle is automatically adjusted according to the impurity content of the influent. The effluent enters a regulating tank. The effective volume of the regulating tank is set according to the design treatment capacity of 6 to 8 hours. Perforated aeration pipes are installed in the tank for intermittent aeration and stirring.

5. The method for efficient treatment and recycling of quartz sand processing wastewater according to claim 1, characterized in that, The coagulation and sedimentation step specifically involves the following steps: effluent from the equalization tank is pumped to a mixing tank, where a composite coagulant consisting of polyaluminum chloride and polyferric sulfate in a 3:1 mass ratio is added. The mixing tank is mechanically stirred. The resulting effluent then enters a flocculation tank, where anionic polyacrylamide is added as a coagulant aid. The flocculation tank employs a folded plate flocculation structure, divided into three stages, with a total hydraulic retention time set to 15 to 20 minutes. The flocculated effluent then enters an inclined tube sedimentation tank, with a surface loading rate set to 1.5 to 2.

0. The inclined tube is set at an angle of 60 degrees and the aperture is set at 50 mm. A sludge hopper is installed at the bottom of the sedimentation tank for regular sludge removal.

6. The method for efficient treatment and recycling of quartz sand processing wastewater according to claim 1, characterized in that, The multi-stage filtration and deep oxidation process specifically involves the following steps: effluent from the intermediate water tank is pumped to a quartz sand filter tank using a pressure pump. The filter media is refined quartz sand with a particle size of 0.5 to 1.0 mm. The backwashing cycle is set to 24 to 48 hours, and the backwashing intensity is set to 15 to 18. The backwashing time is set to 5 to 8 minutes. The effluent from the quartz sand filtration enters the activated carbon filter tank. The filter media is granular activated carbon with an iodine value greater than 800 mg / g. The filtration speed is set to 6 to 8 m / h. The backwashing cycle is set to 7 to 15 days. The effluent from the activated carbon filtration enters the ozone catalytic oxidation tower. The catalyst is ceramic granules loaded with copper oxide and manganese oxide. The filling height is set to 2000 to 2500 mm. The ozone dosage is set to 30 to 50 mg / L. The gas-water ratio is set to 1:1 to 1.5:

1. The hydraulic retention time is set to 30 to 45 minutes. An ozone tail gas destruction device is installed at the top of the reaction tower.

7. The method for efficient treatment and recycling of quartz sand processing wastewater according to claim 1, characterized in that, The sludge treatment and online monitoring steps are as follows: sludge generated from the coagulation sedimentation tank and filtration unit enters the sludge thickening tank by gravity flow; the supernatant is returned to the equalization tank; after thickening, the sludge moisture content drops to 95% to 97% and is transported to the sludge conditioning tank. Polyaluminum chloride and lime are added as conditioning agents at dosages of 2% to 3% and 5% to 8% of the dry sludge mass, respectively. After stirring and mixing for 15 to 20 minutes, the mixture is transported to a plate and frame filter press, with a pressing time of 2 to 3 hours. After dewatering, the sludge cake moisture content drops to below 60%. The online monitoring system sets monitoring points in the equalization tank, coagulation sedimentation tank effluent, filtration effluent, deep oxidation effluent, and reclaimed water tank to monitor parameters such as pH, suspended solids, turbidity, chemical oxygen demand, and flow rate in real time. The monitoring data is transmitted to the central controller.

8. A high-efficiency treatment and recycling system for quartz sand processing wastewater, applied to the high-efficiency treatment and recycling method for quartz sand processing wastewater as described in any one of claims 1 to 7, characterized in that, Includes the following units: The wastewater collection and pretreatment unit is connected to the wastewater discharge outlets of each production process through pipelines, and is equipped with coarse screens, vortex grit chambers, fine screens and equalization tanks in sequence. The coagulation and sedimentation treatment unit is connected to the equalization tank via a booster pump, and is sequentially equipped with a mixing tank, a flocculation tank, and an inclined tube sedimentation tank. The multi-stage filtration unit is connected to the inclined tube sedimentation tank via an intermediate water tank, and quartz sand filter tank and activated carbon filter tank are set in sequence. The deep oxidation treatment unit is connected to the multi-stage filtration treatment unit and is equipped with an ozone generator, a catalytic reaction tower and an ozone exhaust gas destroyer. The recycling and distribution unit is connected to the deep oxidation treatment unit and is equipped with a reclaimed water tank, a separate water supply network, and a disinfection device. The sludge dewatering treatment unit is connected to the coagulation sedimentation treatment unit and the multi-stage filtration treatment unit, and is sequentially equipped with a sludge thickening tank, a sludge conditioning tank and a plate and frame filter press. The intelligent monitoring and control unit is connected to the sensors and actuators of each processing unit, and is equipped with a central controller, online monitoring instruments and communication modules.

9. The efficient treatment and recycling system for quartz sand processing wastewater according to claim 8, characterized in that, Specifically, the intelligent monitoring and control unit is equipped with pH sensors, suspended solids sensors, turbidity sensors, chemical oxygen demand sensors, and electromagnetic flow meters at key nodes of each processing unit. All sensors are connected to the central controller via a 485 bus. The central controller is a programmable logic controller with built-in coagulant dosage optimization algorithms and recycling rate control algorithms. It can automatically calculate and adjust the dosage of coagulant, flocculant aid, and ozone based on real-time monitoring data, while controlling the operating status of each pump, valve, and mixing device. The system has a human-machine interface that displays the operating parameters and water quality data of each unit in real time, and has abnormal alarm and fault self-diagnosis functions.

10. A high-efficiency treatment and recycling system for quartz sand processing wastewater according to claim 8, characterized in that, The recycling and reuse distribution unit is specifically designed as follows: the reuse water tank is divided into a primary reuse water tank and a secondary reuse water tank. The primary reuse water tank is connected to the quartz sand washing process through pipelines, and the secondary reuse water tank is connected to the crushing, screening, and floor washing processes through pipelines. The effluent from the deep treatment first enters the primary reuse water tank. When the water level in the primary reuse water tank reaches the set upper limit, the excess effluent overflows to the secondary reuse water tank. The secondary reuse water tank is equipped with a disinfection device that uses sodium hypochlorite for disinfection at a dosage of 5 to 10 mg / L. Online water quality monitoring instruments and electric regulating valves are installed on each reuse water pipeline. When the reuse water quality does not meet the requirements of the corresponding process, the system automatically switches to tap water supply and returns the substandard water to the regulating tank for reprocessing. The system is equipped with an emergency water supply pipeline.

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