Flocculation synergistic treatment process for industrial production circulating water recycling

Abstract

The present application relates to the field of water pollution control and treatment technology, and discloses a flocculation and synergistic treatment process for industrial production circulating water recycling, comprising: collecting the initial turbidity and transient dynamic viscosity of the industrial production circulating water, adjusting the output power of a mixing device to set a target velocity gradient; reducing the velocity gradient of the transition zone flow field, guiding the water body of the main pipeline to pass through a porous release array to construct an isolation sheath liquid, synchronously matching the extrusion speed of the medicament and the jet speed of the isolation sheath liquid, and physically wrapping the organic flocculant with the isolation sheath liquid; after the conformation of the medicament is relaxed, bridging flocculation is realized; the present application eliminates the physical shear damage of the medicament injection interface, inhibits the mechanical chain degradation of the long chain of the organic flocculant, preserves the complete conformation of the medicament, and then releases the net capture potential of the macromolecule, solves the problem of medicament efficiency attenuation caused by the traditional injection mode, and improves the compactness of the flocculation structure.

Description

Technical Field

[0001] This invention relates to a flocculation-co-treatment process for the reuse of circulating water in industrial production, belonging to the field of water pollution control and treatment technology. Background Technology

[0002] Currently, industrial production circulating water reuse systems generally use flocculation technology to treat suspended particles and colloidal impurities. Inorganic coagulants and organic polymeric flocculants are injected into the circulating water, and a stepped velocity gradient field is established through mechanical stirring to induce the destabilization of particles and their aggregation and growth into flocs with gravity settling characteristics.

[0003] In high-load reuse systems of large manufacturing enterprises, the main axial velocity and system pressure of circulating water are maintained at high levels. The long-chain structure of organic polymer flocculants exhibits high sensitivity to mechanical shear forces. Traditional designs focus on the mixing uniformity of the flow field inside the reaction tank, neglecting the physical environment at the dosing point. When the dosing solution detaches from the dosing nozzle and merges into the high-speed flow field, there is a significant vector difference between the injection linear velocity and the axial velocity of the main fluid, creating transient ultimate shear stress at the dosing interface. Deficiencies in dosing control methods also limit treatment performance. For example, the public... Chinese invention patent application CN120132650A discloses a flocculant preparation and dosing device. The device achieves mechanical dispersion of the flocculant solution by driving a stirring rod to tumble up and down and a dispersing rod to rotate and unfold. This scheme is based on the assumption of a low-speed or static flow field and the control logic is anchored to the uniformity of spatial distribution. However, when facing high-flow-rate and high-pressure industrial circulating water conditions, the dosing mechanism based on mechanical forced shearing and centrifugal spraying is mismatched with the high-speed axial dynamic environment of the main pipe fluid. Transient shear stress is generated at the dosing interface, which causes the ultra-high molecular weight polymer to mechanically break its chains momentarily upon contact with the main flow field, thus reducing its potential for trapping.

[0004] Therefore, how to dynamically adjust the chemical dosing boundary conditions according to the main flow field characteristics of circulating water to eliminate the initial shear stress at the interface where the chemical solution enters, and to achieve dynamic adaptation between the chemical conformation and the flow field environment, is the technical problem to be solved by this invention. Summary of the Invention

[0005] To address the problems in the background art, the technical solution of the present invention is as follows: a flocculation-co-treatment process for industrial production circulating water reuse, comprising the following steps: Step 101: Collect the initial turbidity and transient dynamic viscosity of the industrial production circulating water at the inlet of the first reaction zone; Step 102: Inject inorganic coagulant into the first reaction zone, adjust the mechanical power of the mixing equipment to set the target velocity gradient of the first reaction zone; the magnitude of the target velocity gradient is proportional to the product of the initial turbidity and the transient dynamic viscosity to the power of 0.5; adjust the output speed of the mixing equipment to make the actual velocity gradient reach the target velocity gradient; Step 103: Industrial production circulating water enters the transition zone, and the velocity gradient of the main flow field in the transition zone is adjusted to 15% to 25% of the target velocity gradient; Step 104: Obtain the local axial velocity of the industrial production circulating water at the inlet section of the transition zone; divert a portion of the water from the main pipeline of the industrial production circulating water and spray it out through a porous release array arranged on the axis of the transition zone to form an isolation sheath liquid; adjust the extrusion linear velocity of the organic flocculant in the inner tube of the porous release array so that the ratio of the extrusion linear velocity of the organic flocculant when it leaves the porous release array to the jet linear velocity of the isolation sheath liquid at the outlet of the outer tube of the porous release array is 0.90 to 0.95; the isolation sheath liquid physically encapsulates the organic flocculant. Step 105: After the isolation sheath fluid runs in the transition zone for 0.5m to 1.0m, it naturally diffuses and dissipates, releasing the organic flocculant into the main flow field of the industrial production circulating water. After the organic flocculant completes its spatial conformation in the transition zone, it enters the second reaction zone and performs bridging flocculation by adjusting the velocity gradient of the second reaction zone.

[0006] Preferably, step 104 further includes: step 1041, adjusting the output displacement of the variable frequency dosing pump in real time according to the jet linear velocity of the isolation sheath fluid, and locking the extrusion linear velocity of the organic flocculant. Step 1042, maintaining the extrusion pressure of the organic flocculant at 1.02 to 1.05 times the jet pressure of the isolation sheath fluid, forming a dynamic liquid film flowing in the same direction at the nozzle interface of the porous release array.

[0007] Preferably, step 102 further includes: monitoring the flow fluctuation of the industrial production circulating water in real time based on the flow meter, and simultaneously compensating the output power of the mixing equipment to keep the actual velocity gradient fluctuation amplitude in the first reaction zone within 5% of the target velocity gradient.

[0008] Preferably, the porous release array is installed perpendicular to the flow direction of the main flow field, and the ratio of the inner tube diameter to the annular gap width of the outer tube is 2:1 to 3:1.

[0009] Preferably, step 103 further includes: introducing intermittent low-frequency microbubbles into the bottom of the transition zone, using the wake flow generated by the rising microbubbles to lift the primary microflocs, so that the primary microflocs are suspended in the active reaction layer where the organic flocculant is located.

[0010] Preferably, in step 104, the organic flocculant is an aqueous solution of polyacrylamide with a mass fraction of 0.1% to 0.3%, and the molecular weight of the polyacrylamide is not less than 15 million.

[0011] Preferably, the method further includes: step 106, monitoring the temperature drop slope of the industrial production circulating water; step 107, when the temperature drop slope exceeds a preset threshold, switching the continuous power output of the mixing device in step 102 to square wave pulse output, wherein the peak power of the pulse is 1.5 times the original average value and the valley power is 0.5 times the original average value.

[0012] Preferably, the method further includes: step 108, monitoring the real-time conductivity of the industrial production circulating water; step 109, determining the mixing intensity adjustment parameter based on the real-time conductivity.

[0013] Preferably, in step 104, the flow rate of the isolation sheath fluid is 1% to 3% of the total flow rate of the industrial production circulating water, and the flow rate of the isolation sheath fluid is 5 to 8 times the flow rate of the organic flocculant.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. In the flocculation-co-treatment of recycled industrial production water, by constructing a synchronous matching mechanism between the extrusion linear velocity of organic flocculants and the local axial flow velocity of the circulating water, the transient velocity gradient at the dosing nozzle interface is eliminated. This physical configuration eliminates the extreme shear boundary layer generated when the liquid enters the main flow field, and avoids irreversible mechanical chain breaking and degradation of ultra-high molecular weight polymer chains at the moment of water entry. This mechanism ensures that the polymeric agent entering the low-shear reaction zone has a complete physical conformation, so that the intrinsic entrapment potential of the agent can be fully released, and solves the problem of agent efficacy decay caused by shear damage at the injection interface in traditional processes.

[0015] 2. An energy input compensation mode based on transient dynamic viscosity feedback is established to realize the dynamic response of mixing power to changes in the intrinsic properties of the fluid. By adjusting the velocity gradient of the first reaction zone according to the real-time viscosity, this process ensures that the charge neutralization reaction induced by inorganic coagulants is always within the optimal collision dynamics window when the fluid resistance changes abruptly due to water quality fluctuations. This precise matching for fluid rheological characteristics avoids the phenomenon of insufficient energy dissipation or excessive shearing that occurs in the traditional constant power mode under variable viscosity conditions, thereby improving the generation quality of primary micro-flocs.

[0016] 3. By utilizing the critical relaxation environment formed by the steep descent of the velocity gradient and the synergistic effect of subsequent convergent shear drive, the surface structure of the floc is optimized. In a lower shear field, the polymer chain segments are guided to undergo three-dimensional expansion of spatial conformation. Through the gradually increasing shear force, the expanded molecular chains overcome the spatial steric hindrance between particles to achieve tight cross-linking. This reconstruction of temporal logic results in the final floc having a high-density skeletal structure and a low water encapsulation rate, which improves the gravity separation rate of the floc in the settling unit and reduces the hydraulic load of the subsequent filtration stage. Attached Figure Description

[0017] Figure 1 This is a flowchart of the flocculation synergistic treatment steps in the multi-stage reaction zone of the present invention; Figure 2 This is a diagram showing the evolution of the organic flocculant of the present invention from physical encapsulation to tight cross-linking.

[0018] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0020] A flocculation-co-treatment process for industrial production circulating water reuse includes the following steps: Step 101: Collect the initial turbidity and transient dynamic viscosity of the industrial production circulating water at the inlet of the first reaction zone; Step 102: Inject inorganic coagulant into the first reaction zone, adjust the mechanical power of the mixing equipment to set the target velocity gradient of the first reaction zone; the magnitude of the target velocity gradient is proportional to the product of the initial turbidity and the transient dynamic viscosity to the power of 0.5; adjust the output speed of the mixing equipment to make the actual velocity gradient reach the target velocity gradient; Step 103: Industrial production circulating water enters the transition zone, and the velocity gradient of the main flow field in the transition zone is adjusted to 15% to 25% of the target velocity gradient; Step 104: Obtain the local axial velocity of the industrial production circulating water at the inlet section of the transition zone; divert a portion of the water from the main pipeline of the industrial production circulating water and spray it out through a porous release array arranged on the axis of the transition zone to form an isolation sheath liquid; adjust the extrusion linear velocity of the organic flocculant in the inner tube of the porous release array so that the ratio of the extrusion linear velocity of the organic flocculant when it leaves the porous release array to the jet linear velocity of the isolation sheath liquid at the outlet of the outer tube of the porous release array is 0.90 to 0.95; the isolation sheath liquid physically encapsulates the organic flocculant. Step 105: After the isolation sheath fluid runs in the transition zone for 0.5m to 1.0m, it naturally diffuses and dissipates, releasing the organic flocculant into the main flow field of the industrial production circulating water. After the organic flocculant completes its spatial conformation in the transition zone, it enters the second reaction zone and performs bridging flocculation by adjusting the velocity gradient of the second reaction zone.

[0021] Preferably, step 104 further includes: step 1041, adjusting the output displacement of the variable frequency dosing pump in real time according to the jet linear velocity of the isolation sheath fluid, and locking the extrusion linear velocity of the organic flocculant. Step 1042, maintaining the extrusion pressure of the organic flocculant at 1.02 to 1.05 times the jet pressure of the isolation sheath fluid, forming a dynamic liquid film flowing in the same direction at the nozzle interface of the porous release array.

[0022] Preferably, step 102 further includes: monitoring the flow fluctuation of the industrial production circulating water in real time based on the flow meter, and simultaneously compensating the output power of the mixing equipment to keep the actual velocity gradient fluctuation amplitude in the first reaction zone within 5% of the target velocity gradient.

[0023] Preferably, the porous release array is installed perpendicular to the flow direction of the main flow field, and the ratio of the inner tube diameter to the annular gap width of the outer tube is 2:1 to 3:1.

[0024] Preferably, step 103 further includes: introducing intermittent low-frequency microbubbles into the bottom of the transition zone, using the wake flow generated by the rising microbubbles to lift the primary microflocs, so that the primary microflocs are suspended in the active reaction layer where the organic flocculant is located.

[0025] Preferably, in step 104, the organic flocculant is an aqueous solution of polyacrylamide with a mass fraction of 0.1% to 0.3%, and the molecular weight of the polyacrylamide is not less than 15 million.

[0026] Preferably, the method further includes: step 106, monitoring the temperature drop slope of the industrial production circulating water; step 107, when the temperature drop slope exceeds a preset threshold, switching the continuous power output of the mixing device in step 102 to square wave pulse output, wherein the peak power of the pulse is 1.5 times the original average value and the valley power is 0.5 times the original average value.

[0027] Preferably, the method further includes: step 108, monitoring the real-time conductivity of the industrial production circulating water; step 109, determining the mixing intensity adjustment parameter based on the real-time conductivity.

[0028] Preferably, in step 104, the flow rate of the isolation sheath fluid is 1% to 3% of the total flow rate of the industrial production circulating water, and the flow rate of the isolation sheath fluid is 5 to 8 times the flow rate of the organic flocculant.

[0029] Example 1: When the water volume is... In the scenario of recycling circulating water in steel production, when the system faces the condition that the initial turbidity of the influent fluctuates and the transient dynamic viscosity of the fluid shifts due to changes in water temperature, the initial turbidity of the industrial production circulating water at the inlet of the first reaction zone is collected. and transient dynamic viscosity Based on initial turbidity and transient dynamic viscosity The product of 0.5 and 0.5 determines the target velocity gradient in the first reaction zone. The microprocessor is based on the formula A numerical power model is constructed, where P represents the mechanical power of the hybrid equipment. The transient dynamic viscosity is given by V, where V is the effective volume of the first reaction zone. The transient dynamic viscosity value input from the sensor is read. The negative zero-fifth power mathematical characteristic term is extracted and multiplied by the initial turbidity value representing the particle collision base. The calculated product is converted into an analog voltage signal and written into the instruction register of the mixing equipment servo controller. The output power of the mixing equipment is controlled to make the actual velocity gradient in the first reaction zone reach the target velocity gradient. This ensures that the actual velocity gradient fluctuation amplitude within the first reaction zone remains within the target velocity gradient range. Within 5%.

[0030] Industrial production circulating water enters the transition zone, and the system adjusts the velocity gradient of the main flow field in the transition zone to the target velocity gradient. 20% of the total flow rate is obtained, and the local axial velocity of the industrial production circulating water at the inlet section of the transition zone is also obtained. A portion of the water, accounting for 2% of the total flow rate, is diverted from the main pipeline to a bypass where a hydrocyclone and a 10mm orifice are connected in series. Up to 20 In a continuous pipeline system without mechanical agitation, the microporous pleated filter cartridge, in order to achieve the aforementioned velocity gradient adjustment, has its transition zone constructed as a gradually expanding diffuser section with a smoothly increasing cross-sectional area along the flow direction. As the main body of circulating water naturally propels axially to a wider flow cross-section without pumping, its absolute axial linear velocity and internal momentum exchange rate naturally decrease according to the continuity equation. The turbulent kinetic energy dissipation rate of large-scale eddies within the fluid is thus physically suppressed. Therefore, purely by utilizing the spatial expansion and change of the flow channel geometry, the passively generated surface shear rate of the flow field is precisely established at the target velocity gradient. Within a preset ratio range, the hydrocyclone separates heavy impurities with a density greater than that of the aqueous phase. The microporous pleated filter cartridge retains the primary active colloids, precipitating a destabilized inert liquid phase. This destabilized inert liquid phase is guided into the outer tube of the porous release array arranged on the axis of the transition zone and sprayed out to form an isolation sheath liquid. The extrusion linear velocity of the polyacrylamide aqueous solution in the inner tube of the porous release array is adjusted so that the ratio of the extrusion linear velocity of the polyacrylamide aqueous solution when it leaves the porous release array to the jet linear velocity of the isolation sheath liquid at the outlet of the outer tube of the porous release array is 0.92. The isolation sheath liquid physically encapsulates the polyacrylamide aqueous solution. The solution is prepared, and the extrusion pressure of the polyacrylamide aqueous solution is maintained at 1.03 times the jet pressure of the isolation sheath liquid. A dynamic liquid film with the same direction of flow is formed at the nozzle interface of the porous release array. After the isolation sheath liquid flows with the flow for 0.8m in the transition zone, it naturally diffuses and dissipates, releasing the polyacrylamide into the main flow field of the industrial production circulating water. The polyacrylamide is selected as a polyacrylamide aqueous solution with a molecular weight of 18 million and a mass fraction of 0.2%. After the polyacrylamide completes the spatial conformation expansion in the transition zone, it enters the second reaction zone, and bridging flocculation is carried out by adjusting the velocity gradient of the second reaction zone.

[0031] Example 2: In an industrial hydrodynamic simulation test platform with a processing capacity of 5000 m³ / h, a high-velocity transport environment for circulating water in steel production was simulated using a physical pipeline loop. The platform was equipped with a pressure transmitter with a sampling frequency of no less than 100 Hz, an online turbidity meter with a measurement accuracy of 0.1 NTU, and an online viscometer with a range covering 1 mPa·s to 50 mPa·s. The raw data used in the experiment came from sensor signal sequences collected by the platform during continuous operation. To simulate the electromagnetic environment of the industrial site and verify process stability, Gaussian white noise with a signal-to-noise ratio of 20 dB and 50 Hz power frequency interference were actively superimposed on the collected data. The sampling period was determined based on the balance logic between the sampling theorem and the system's computational load. As the spectral bandwidth of the monitored signal increased, the sampling period tended towards the lower limit of its range to suppress signal aliasing. In the typical operating conditions of this example, the sampling period was determined to be 10 ms to capture transient dynamic viscosity. Reduce controller energy consumption during fluctuations, target velocity gradient Calculation constants Based on a pre-established calibration procedure, the critical shear strength at which the colloidal charge neutralization reaction reaches 90% conversion was determined by varying the flow rate of a glycerol aqueous solution of known viscosity. The proportional relationship between physical input and physical input.

[0032] At initial turbidity 150 NTU and transient dynamic viscosity Under the experimental condition of 1.2 mPa·s, the control group used constant power stirring and injected organic flocculant directly into the main flow field through a common vertical pipe. The experimental group used a flocculation-co-treatment process for industrial circulating water reuse. The local shear stress at the dosing nozzle interface of the control group was measured in real time to be 450 Pa. Due to the lack of a physical isolation mechanism, the long chains of polyacrylamide with a molecular weight of 18 million and a mass fraction of 0.2% experienced chain breakage upon entering the flow field, resulting in a decrease in the density of effective bridging sites for the agent entering the second reaction zone. The average particle size of the final flocs generated in the control group was measured to be 185 mm. The settling rate was 2.1 mm / s. In the experimental group, the jet linear velocity of the isolation sheath fluid was adjusted to 1.1 times the local axial flow velocity, and an extrusion pressure ratio of 1.03 times was maintained in the inner tube. This allowed the polyacrylamide aqueous solution to smoothly transition into the flow field under the wrapping of a dynamic liquid film flowing in the same direction. Real-time monitoring showed that the transient shear stress at the dosing interface of the experimental group decreased to 12 Pa, preserving the long-chain conformation of the polyacrylamide. The average particle size of the flocs generated in the experimental group increased to 512 mm / s. Furthermore, the settling rate increased to 8.5 mm / s.

[0033] To verify the response of this process to water quality fluctuations and to determine the parameter boundaries, an initial turbidity was set. Three gradient sample groups, namely 50 NTU, 150 NTU, and 350 NTU, were used to investigate the performance evolution of the ratio of the organic flocculant extrusion linear velocity to the isolation sheath fluid jet linear velocity as the ratio increased from 0.85 to 1.05 at each gradient. Experimental data showed that when the ratio was in the range of 0.90 to 0.95, the residual turbidity of the effluent remained stable below 1.5 NTU. When the ratio decreased to 0.85, due to the extrusion velocity being lower than the sheath fluid flow velocity, an inward entrainment effect formed at the dosing port, leading to partial... The agent comes into contact with the high-shear fluid before the liquid film forms, and the floc settling rate decreases to 3.4 mm / s. When the ratio reaches 1.05, the agent extrusion pressure triggers radial instability diffusion in the liquid film, disrupting the physical encapsulation integrity of the sheath fluid and slowing down the floc particle size growth rate. This indicates that the rate ratio range of 0.90 to 0.95 is the performance inflection point for balancing interfacial shear suppression and liquid film stability requirements. Furthermore, when facing a high turbidity impact of 350 NTU, this process utilizes transient dynamic viscosity... Feedback compensates for the mixing energy in the first reaction zone, maintaining the charge neutralization reaction rate constant at [value missing]. This experiment, through analysis of measured data on different turbidity loads and linear velocity ratio gradients, confirmed that the process eliminates physical shear damage at the agent injection interface through the synergistic effect of the isolation sheath liquid physical encapsulation mechanism and viscosity compensation energy input mode, allowing the polyacrylamide's entrapment potential to be released. After eliminating the risk of chain breakage caused by flow velocity vector differences, the system maintains a high-density skeletal structure and gravity separation rate of flocs under fluctuating conditions from 50 NTU to 350 NTU, solving the problems of agent efficiency decay and insufficient floc density caused by shear mismatch at the injection interface in traditional processes.

[0034] Example 3: In a steel plant's circulating water reuse system, where a winter cold wave causes the influent water temperature to drop sharply from 25°C to 15°C within 1 hour, the kinematic viscosity of water increases as the temperature decreases. This process determines the proportional coefficient in the calculation formula through calibration. The calibration methods include: pre-setting initial turbidity. Standard kaolin suspensions of 50 NTU, 100 NTU, and 200 NTU were used, with glycerol added to adjust the transient dynamic viscosity of the solutions. Within the gradient range of 1.0 mPa·s to 5.0 mPa·s; adjust the rotational speed of the mixing equipment within the first reaction zone, and measure the average collision frequency of the primary micro-flocs using a particle counter; when the average collision frequency reaches its maximum value, record the current actual velocity gradient. Least squares linear fitting was performed on multiple sets of measured data to determine the proportionality coefficient. The value is 1.2.

[0035] The system monitors the temperature drop slope of the circulating water in industrial production. The temperature drop slope is defined as the ratio of the temperature difference between the current sampling time and the sampling time 10 minutes ago to the time step. When the temperature drop slope exceeds the preset threshold of 2℃ / h, the mixing equipment control unit switches the continuous power output to square wave pulse output, with a pulse frequency of 50Hz and a duty cycle of 50%. Through the alternating action of the pulse peak power being 1.5 times the original average and the valley power being 0.5 times the original average, the eddy current stripping effect caused by the transient shear stress change in the fluid is utilized to break the hydration layer that has thickened due to the increase in viscosity, and maintain the particle collision energy required for the charge neutralization reaction.

[0036] After the industrial circulating water enters the transition zone, to address the issue of slow floc growth and easy settling at low temperatures, intermittent low-frequency microbubbles are introduced through a microbubble generator array arranged at the bottom of the transition zone. The pulse period of the intermittent low-frequency microbubbles is 5s, the on-time is 1s, and the off-time is 4s. The aeration rate of the microbubbles is controlled at 0.05% of the circulating water volumetric flow rate. This allows the upward wake generated by the microbubbles during their ascent to carry vertically upward momentum, counteracting the gravitational component of the primary microflocs. In the actual multiphase flow field evolution, due to the extremely small mass of the microbubbles, they are instantly entrained by the overall high-energy axial fluid of thousands of cubic meters per hour after leaving the array. This maintains a near-zero relative velocity with the main circulating water, resulting in horizontal axial translation. In a relatively stationary reference frame, the microbubbles are less affected by the surrounding transverse streamlines and slide upward under the buoyancy drive within the fluid, triggering... The surface flow, in a state of undamaged following, continuously and stably applies the vertical lift vector to the heavy primary flocs moving at the same velocity, achieving dynamic coexistence and self-consistency between the surface lift field and the overall high-speed scouring environment. In this environment, a sheath fluid is constructed by circulating water accounting for 1.5% of the total flow rate through the main pipeline. The variable frequency dosing pump is adjusted according to the jet linear velocity of the sheath fluid to lock the ratio of the extrusion linear velocity of the 0.15% polyacrylamide aqueous solution to the jet linear velocity of the sheath fluid at 0.93. This allows the 22 million molecular weight polymer chains to be smoothly released under the physical encapsulation of the sheath fluid. Through the synergistic effect of pulse power compensation and microbubble potential energy lift, the system maintains the compactness of the floc structure under the variable viscosity conditions induced by drastic temperature changes. Finally, the turbidity of the effluent from the sedimentation tank is stabilized below 1.2 NTU.

[0037] Example 4: In the process of adapting the system to different batches of polyacrylamide, since different batches of the agent exhibit different flow resistances at the same mass fraction, the process maps the flow rate of the variable frequency dosing pump and the porous release array in the upstream pipe section of the first reaction zone. The transient linear velocity of the extruded liquid is collected by a flow meter set at the nozzle of the porous release array. The variable frequency dosing pump is adjusted in 5Hz steps within the frequency range of 0Hz to 60Hz. The linear velocity of the polyacrylamide aqueous solution when it leaves the nozzle of the inner pipe of the porous release array at each frequency point is recorded, and the numerical correspondence between frequency and linear velocity is generated. The jet linear velocity of a portion of the water flowing out of the main pipeline as the isolation sheath liquid is collected. The control unit adjusts the output frequency of the variable frequency dosing pump according to the numerical correspondence so that the ratio of the extrusion linear velocity of the polyacrylamide aqueous solution when it leaves the porous release array to the jet linear velocity of the isolation sheath liquid at the outlet of the outer pipe of the porous release array is 0.92. The physical encapsulation generated by the isolation sheath liquid at the dosing interface is utilized.

[0038] When the system faces operating conditions where the temperature fluctuation of industrial production circulating water exceeds 10°C, in order to suppress the transient dynamic viscosity of the fluid... During the commissioning process in the transition zone, the interface wave induced by the change was monitored by using a differential pressure sensor to collect the extrusion pressure of the inner tube agent and the jet pressure of the outer tube isolation sheath liquid. The control unit calculated a pressure compensation operator to maintain the extrusion pressure of the polyacrylamide aqueous solution at 1.03 times the jet pressure of the isolation sheath liquid. A uniform dynamic liquid film was generated at the nozzle interface of the porous release array. After traveling 0.8m in the transition zone, the isolation sheath liquid diffused and dissipated with the flow field, releasing polyacrylamide. The polyacrylamide underwent spatial conformational expansion under a low velocity gradient environment. Through combined pressure and velocity regulation, the average particle size of the flocs at the inlet of the settling tank was measured to be 515 μm under temperature fluctuation conditions. .

[0039] Example 5: In a scenario where coking chemical wastewater with a treatment capacity of 8000 m³ / h is reused, this process involves deploying a high-frequency ultrasonic flow meter at the inlet of the first reaction zone to collect the local axial flow velocity. By controlling the ratio of the inner pipe diameter to the outer pipe annular gap width of the porous release array to 2.5:1, the flow rate regulation operator is adjusted to control the outflow of a portion of the water to be 2% of the total industrial production circulating water flow rate. This generates the output frequency of the drainage pump and the jet linear velocity of the isolation sheath fluid at the outlet of the outer pipe of the porous release array. The numerical relationship table ensures that the Reynolds number of the isolation sheath fluid at the porous release array nozzle is 1750, thereby establishing a momentum balance benchmark on the axis of the transition zone. When the system faces the condition of viscosity fluctuations caused by differences in dissolution and maturation times between different batches of polyacrylamide, this process monitors the flow characteristics of the agent through an online viscometer, and the control system adjusts the frequency output of the variable frequency dosing pump according to the numerical relationship table to ensure that the extrusion linear velocity of the polyacrylamide aqueous solution when it leaves the porous release array is controlled. The jet linear velocity of the isolation sheath fluid at the outlet of the porous release array outer tube The ratio is maintained at 0.93, and the extrusion pressure of the inner tube is adjusted by the differential pressure control loop to keep the extrusion pressure of the polyacrylamide aqueous solution constant at 1.04 times the pressure of the isolation sheath liquid jet. By generating a dynamic liquid film of uniform thickness at the interface of the porous release array nozzle, the long polymer chains with a molecular weight of not less than 15 million are released into the main flow field of the transition zone under the boundary conditions that eliminate the difference in flow velocity vector.

[0040] In industrial production circulating water reuse scenarios with high salinity, the system faces challenges related to the conductivity of the influent. The water replenishment ratio changes from 1500 Surge to 4500 Under these operating conditions, the increased electrolyte concentration alters the chemical destabilization rate by compressing the colloidal double layer effect. Therefore, a conductivity sensor is installed at the inlet of the first reaction zone to monitor the real-time conductivity of the industrial production circulating water. The control unit determines the mixing intensity adjustment parameters based on the real-time conductivity. The difference between the real-time conductivity and the standard circulating water conductivity benchmark value is extracted, and multiplied by the pre-stored ion strength sensitivity coefficient. The product is then subtracted from the constant 1 to calculate the mixing intensity adjustment parameter with a value less than 1. Adjust the mixing intensity parameter As an attenuation multiplier, it is multiplied by the current set reference Hertz frequency of the frequency converter. The attenuated target frequency command is sent to the speed control pin of the mixing equipment in the first reaction zone via the hardware data bus, reducing the actual output speed of the motor. The specific calibration process is as follows: standard water samples with different conductivity gradients are prepared in a laboratory environment. The time constant for the primary micro-flocs to reach charge neutralization equilibrium under the same speed gradient is measured. An inverse linear mapping model of conductivity and mixing intensity is established. Based on the establishment of this calibration model, the first derivative constant representing the decrease rate of the optimal matching viscosity response caused by each unit increase in conductivity per centimeter is extracted from the mapping model. After normalization extremum processing, the aforementioned pre-stored ion intensity sensitivity coefficient of the system is solidified. This value, as an intrinsic empirical constant that does not change with fluctuations under a single operating condition, is pre-programmed into the read-only memory of the control unit. This completes the verifiable numerical benchmark for the abstract data processing link of the system based on real-time conductivity to solve the attenuation multiplier. When the conductivity is monitored... When the temperature rises, the system automatically reduces the mixing intensity adjustment parameter. By reducing the output frequency of the mixing equipment to decrease the actual velocity gradient in the first reaction zone, excessive shearing damage to the already formed compact neutralization centers is avoided under high ionic strength conditions. This ensures that the residual turbidity of the sedimentation tank effluent remains below 1.0 NTU even with significant fluctuations in salinity. To ensure that the isolating sheath fluid effectively physically encapsulates the organic flocculant under different loads, the system is designed based on the local axial flow velocity of the main pipeline of the industrial production circulating water. The flow rate is dynamically adjusted to control the flow rate of the isolation sheath fluid to 2.5% of the total flow rate of the industrial production circulating water, while maintaining the flow rate of the isolation sheath fluid at 6.5 times the flow rate of the polyacrylamide aqueous solution. Under this ratio, a liquid film layer with sufficient momentum thickness is formed in the annular gap of the porous release array. When the flow rate of the isolation sheath fluid is less than 5 times the flow rate of the polyacrylamide aqueous solution, the physical strength of the dynamic liquid film is insufficient to resist the turbulent penetration of the external flow field, which will lead to local exposure and chain breakage of the long polymer chains. When the ratio exceeds 8 times, the excessive isolation sheath fluid will dilute the effective concentration of the agent in the local area and prolong the relaxation time of the agent from the coiled state to the three-dimensional unfolded conformation. By locking the flow rate at 1% to 3% of the total flow rate and maintaining the sheath flow ratio in the range of 5 to 8 times, the polyacrylamide achieves complete release and conformational unfolding of the entire molecular chain after running for 0.7m, solving the problem of traditional injection methods in complex and fluctuating conditions. The technical problem of unstable utilization rate of the drug's netting potential was further verified by flow field calculations. The aforementioned set operating boundaries of the drainage flow rate and sheath flow ratio strictly correspond to the spatial displacement scale determined by the combined coupling of the radial consumption time of the isolation sheath fluid and the axial convection time. Under the set flow parameters, the Reynolds number inside and outside the sheath fluid annulus transitions smoothly. The liquid film is rigidly constrained and slowly diffuses and peels off to the outer edge only by relying on the molecular concentration gradient. The absolute axial translation distance corresponding to the complete attenuation and penetration of its material field is objectively locked within the effective flow field range of 0.5m to 1.0m. Once the boundary is out of control and the running distance is less than 0.5m, it means that the main fluid is extremely turbulent, causing the radial shear penetration to be too fast, and the drug will face the risk of physical failure due to destruction before it can spread. If it is greater than 1.0m, it means that the initial liquid film ratio is too high, causing the polymer long chain to directly miss the optimal kinetic window period for netting and collision with the primary micro-flocs in the transition zone.

[0041] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A flocculation-co-treatment process for industrial production circulating water reuse, characterized in that, Includes the following steps: Step 101: Collect the initial turbidity and transient dynamic viscosity of the industrial production circulating water at the inlet of the first reaction zone; Step 102: Inject inorganic coagulant into the first reaction zone, adjust the mechanical power of the mixing equipment to set the target velocity gradient of the first reaction zone; the magnitude of the target velocity gradient is proportional to the product of the initial turbidity and the transient dynamic viscosity to the power of 0.5; adjust the output speed of the mixing equipment to make the actual velocity gradient reach the target velocity gradient; Step 103: Industrial production circulating water enters the transition zone, and the velocity gradient of the main flow field in the transition zone is adjusted to 15% to 25% of the target velocity gradient; Step 104: Obtain the local axial velocity of the industrial production circulating water at the inlet section of the transition zone; divert a portion of the water from the main pipeline of the industrial production circulating water and spray it out through a porous release array arranged on the axis of the transition zone to form an isolation sheath liquid; adjust the extrusion linear velocity of the organic flocculant in the inner tube of the porous release array so that the ratio of the extrusion linear velocity of the organic flocculant when it leaves the porous release array to the jet linear velocity of the isolation sheath liquid at the outlet of the outer tube of the porous release array is 0.90 to 0.95; the isolation sheath liquid physically encapsulates the organic flocculant. Step 105: After the isolation sheath fluid runs in the transition zone for 0.5m to 1.0m, it naturally diffuses and dissipates, releasing the organic flocculant into the main flow field of the industrial production circulating water. After the organic flocculant completes its spatial conformation in the transition zone, it enters the second reaction zone and performs bridging flocculation by adjusting the velocity gradient of the second reaction zone.

2. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, Step 104 further includes: Step 1041, adjusting the output displacement of the variable frequency dosing pump in real time according to the jet linear velocity of the isolation sheath fluid, and locking the extrusion linear velocity of the organic flocculant. Step 1042, maintaining the extrusion pressure of the organic flocculant at 1.02 to 1.05 times the jet pressure of the isolation sheath fluid, forming a dynamic liquid film flowing in the same direction at the nozzle interface of the porous release array.

3. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, Step 102 further includes: monitoring the flow fluctuation of the industrial production circulating water in real time based on the flow meter, and simultaneously compensating the output power of the mixing equipment to keep the actual velocity gradient fluctuation amplitude in the first reaction zone within 5% of the target velocity gradient.

4. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, The porous release array is installed perpendicular to the flow direction of the main flow field, and the ratio of the inner tube diameter to the annular gap width of the outer tube is 2:1 to 3:

1.

5. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, Step 103 further includes: introducing intermittent low-frequency microbubbles into the bottom of the transition zone, using the wake flow generated by the rising microbubbles to lift the primary microflocs, so that the primary microflocs are suspended in the active reaction layer where the organic flocculant is located.

6. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, In step 104, the organic flocculant is an aqueous solution of polyacrylamide with a mass fraction of 0.1% to 0.3%, and the molecular weight of the polyacrylamide is not less than 15 million.

7. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, It also includes: step 106, monitoring the temperature drop slope of the industrial production circulating water; step 107, when the temperature drop slope exceeds a preset threshold, switching the continuous power output of the mixing device in step 102 to square wave pulse output, wherein the peak power of the pulse is 1.5 times the original average value and the valley power is 0.5 times the original average value.

8. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, It also includes: step 108, monitoring the real-time conductivity of industrial production circulating water; step 109, determining the mixing intensity adjustment parameters based on the real-time conductivity.

9. The flocculation-co-treatment process for industrial production circulating water reuse according to claim 1, characterized in that, In step 104, the flow rate of the isolation sheath fluid is 1% to 3% of the total flow rate of the industrial production circulating water, and the flow rate of the isolation sheath fluid is 5 to 8 times the flow rate of the organic flocculant.

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