EVCL (Ethylene Vinyl Chloride) emulsion glue mixing and proportioning equipment and mixing method

Abstract

The invention relates to the technical field of emulsion glue preparation, and discloses EVCL emulsion glue mixing and proportioning equipment and a mixing method.The EVCL emulsion glue mixing and proportioning equipment comprises a premixing tank provided with a stirring assembly, and further comprises a circulating bypass communicated with the premixing tank, an inlet of the circulating bypass is taken from a bottom outlet of the premixing tank, an outlet returns to the premixing tank in a submerged backflow mode, and the circulating bypass sequentially forms a Venturi flow channel of a contraction section, a throat part and a diffusion section; and the detection unit is arranged in the circulating bypass. Venturi-four-ring electrode conductivity detection, adjustable insulating ring electrode constant online fine adjustment and pH, viscosity and temperature three-way independent branch pipe monitoring are integrated in the same circulating bypass, so that the stability of the A-phase premixing process does not depend on fixed time any more; however, according to the objective criterion that four signals of conductivity, pH, viscosity and temperature synchronously reach a plateau phase, automatic termination is achieved, and the risk of follow-up emulsion glue performance fluctuation is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of emulsion glue preparation, in particular to an EVCL emulsion glue mixing and proportioning device and a mixing method. BACKGROUND

[0002] The ethylene-vinyl chloride polymer emulsion (EVCL emulsion) is a water-based emulsion with a vinyl chloride content of >70%, which has mature applications in the field of woodworking glue such as panel glue and finger joint glue. It can replace traditional urea-formaldehyde glue to produce formaldehyde-free particle board, and is especially suitable for heavy-duty boards. Moreover, it does not contain formaldehyde substances and has no residual odor, which meets the industry standards and is suitable for home and industrial scenarios.

[0003] Currently, the existing production of EVCL emulsion mainly adopts batch stirring process, and the general process is as follows: (1) A-phase premixing: deionized water is added to a premixing tank, and under low shear and temperature control conditions (commonly 20-30 ℃), defoaming / wetting, film-forming, and rheological additives are sequentially added to make them fully dispersed, and then EVCL emulsion is slowly added and uniformly mixed with the water phase until the system appearance and viscosity tend to be stable; (2) B-phase preparation: crosslinking / adhesion, pH adjustment, or preservative components are added in a separate container or segmented in the same tank to form a solution / dispersion compatible with A-phase; (3) AB-phase merging and post-processing: B-phase is added to A-phase (or added in steps) according to process requirements, shear and temperature rise are controlled, and after uniform mixing, it is left to stand and defoam, and then it is filtered (such as 80-120 mesh) and filled to complete.

[0004] In the above process, A-phase premixing plays a decisive role in the accuracy of the final proportioning and product consistency. The premixing time interval in A-phase premixing is 10-30 min, but the A-phase is mainly terminated by "stability", so it is necessary to determine the specific premixing time within this time interval to avoid affecting the mixing quality of the subsequent AB-phase due to too short or too long stirring time. SUMMARY

[0005] The present application aims to provide an EVCL emulsion glue mixing and proportioning device and a mixing method to solve at least one technical problem in the prior art.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solution: an EVCL emulsion glue mixing and proportioning device, comprising a premixing tank provided with a stirring assembly, further comprising: A circulation bypass is in communication with the premixing tank and is vertically installed, an inlet of the circulation bypass is taken from a bottom outlet of the premixing tank, and an outlet returns to the premixing tank in a submergence backflow manner, wherein the circulation bypass sequentially forms a Venturi flow channel with a contraction section, a throat section and a diffusion section; A detection unit is arranged in the circulation bypass, and the detection unit comprises: A four-ring electrode is embedded in the inner wall of the throat section, the four-ring electrode comprises four electrode rings arranged in sequence, two electrode rings on the sides are used for power supply, two electrode rings on the inner side are used for pressure measurement, and an insulating ring axially adjustable is arranged between the two electrode rings on the inner side.

[0007] Optionally, an annular groove is formed in the outer wall of the circulation bypass, a threaded pipe is rotatably arranged in the annular groove, a thread is formed in the inner annular wall of the threaded pipe, a latch is fixedly arranged on the outer wall of the insulating ring, and the free end of the latch is engaged with the thread of the inner annular wall of the threaded pipe, a long groove is formed in the inside of the circulation bypass for sliding adjustment of the latch, and the outer annular wall of the insulating ring always separates the long groove from the inner wall of the throat section of the circulation bypass.

[0008] Optionally, a lip ring is formed on each side of the insulating ring, a shallow annular groove is formed in the inner wall of the throat section of the circulation bypass, and the lip ring is attached to the shallow annular groove, thereby separating the embedding groove of the insulating ring from the inner wall of the throat section.

[0009] Optionally, two branch bypasses are in communication with the rear half of the diffusion section of the circulation bypass, the inlet and outlet of each of the two branch bypasses are connected to the rear half of the circulation bypass, a pH monitoring module and a viscosity detection module are respectively arranged in the two branch bypasses, and a temperature monitoring module is arranged at the backflow port between the circulation bypass and the premixing tank. The control unit is electrically connected to the detection unit, the pH monitoring module, the viscosity detection module and the temperature monitoring module, and is configured to generate a signal indicating that the A phase is stable based on the stability criteria of conductivity, pH, viscosity and temperature.

[0010] Optionally, a thin pipe is connected to the top end of the circulation bypass, and an exhaust valve is arranged at the end of the thin pipe.

[0011] Optionally, a spiral guide vane is formed on the inner wall of the contraction section of the circulation bypass, and the A phase forms a spiral liquid flow in the throat section of the circulation bypass after being guided by the spiral guide vane.

[0012] Optionally, the stirring assembly comprises a partition plate fixed to the premixing tank near the lower inner wall, the partition plate divides the premixing tank into an upper premixing cavity and a lower transfer cavity, a rotatable stirring shaft is arranged on the top of the partition plate, a plurality of stirring blades are arranged on the outer wall of the stirring shaft, and the liquid inlet of the circulation bypass is in communication with the transfer cavity.

[0013] Optionally, the inner bottom of the premixing tank is provided with a rotating box driven to rotate by a servo motor, an inner wall of the rotating box is slidably provided with a piston block, an inside of the piston block is fixedly provided with a piston cross rod, two ends of the piston cross rod pass through two sides of the rotating box and are sealingly and slidably connected with outer walls of the two sides of the rotating box, an eccentric ring in an eccentric design is fixed to the bottom of the partition plate, and the two ends of the piston cross rod can alternately contact with an inner wall of the eccentric ring, one-way liquid discharge ports are formed in the two sides of the rotating box, the top of the rotating box is communicated with a liquid inlet pipe, a one-way liquid inlet valve is arranged in the liquid inlet pipe, the top end of the liquid inlet pipe passes through the top of the partition plate and is fixedly arranged with the bottom end of the stirring shaft in a same axis, a lumen is formed in the inside of the stirring shaft and communicated with the liquid inlet pipe, and a plurality of liquid suction holes with different heights and communicated with the lumen are formed in the outer wall of the stirring shaft.

[0014] Optionally, rollers are rotatably arranged at the two ends of the piston cross rod.

[0015] A mixing method of an EVCL emulsion glue mixing and proportioning equipment, comprising the following steps: S1, in the premixing phase of phase A, the raw liquid in the premixing tank is premixed and stirred by the internal stirring assembly; S2, secondly, the raw liquid in the premixing is discharged from the bottom outlet of the premixing tank and enters into the circulating bypass, and then returns to the premixing tank in a liquid underflow manner after passing through the Venturi flow channel of the contraction section, the throat section and the diffusion section in sequence, so as to form a circulating flow path; S3, wherein, in the process of circulation, the raw liquid forms a constant cross section and a stable linear velocity at the throat section, and the four electrode rings arranged in flush with the inner wall of the throat section are E1, E2, E3 and E4 in sequence along the flow direction, the outer E1 and E4 are applied with a small alternating current I by the transmitter to establish an axial electric field in the liquid, and the inner E2 and E3 are connected to a high input impedance differential amplifier to only sample the potential without current, so that the potential difference ΔV is read, and the conductance G=I / ΔV is obtained by Ohm's law, and the liquid conductivity κ=K×G can be obtained by combining the electrode constant K, so as to monitor the conductivity to determine whether phase A is "stable"; S4, wherein, an adjustable insulation ring is arranged between E2 and E3, the inner surface of the insulation ring is flush with the inner wall of the throat section to form a pure insulation straight cylinder between E2 and E3, and the insulation straight cylinder is axially moved or positioned by intervals to change the axial length L_eff of the insulation straight cylinder effectively "exposed" on the fluid side, when the insulation ring is pushed downstream, L_eff increases→K increases, and vice versa K decreases, by adjusting the insulation ring, the best range window can be aligned with different formula / conductivity intervals, after adjustment, the position / interval and K corresponding table is established by fast calibration with standard liquid, in the running, κ=K×(I / ΔV) can be stably output, and when the formula or working condition is changed, only the corresponding K value needs to be switched.

[0016] Compared with the prior art, the application has the following advantages: First, the application integrates "Venturi-four-ring electrode" conductivity detection, adjustable insulation ring electrode constant online fine-tuning, and pH, viscosity, and temperature three-way independent branch monitoring in the same circulation bypass, so that the "stability" of the A-phase premixing process is no longer dependent on fixed time, but is automatically terminated based on the objective criterion of synchronous platform period of conductivity, pH, viscosity, and temperature four signals, which significantly improves the batch consistency, avoids overmixing or undermixing, and reduces the risk of subsequent emulsion glue performance fluctuation.

[0017] Second, the application designs the insulation ring to be flush with the inner wall of the throat and axially adjustable, changes the effective insulation length L_eff between E2 and E3 by using a threaded pipe-latch mechanism, realizes online stepless adjustment of the electrode constant K, and cooperates with the scale disc and standard liquid for rapid calibration, so that the measurement optimal range can be aligned with different formulations (low, medium, and high conductivity regions) without replacing the probe, which widens the applicable bandwidth of the same set of equipment, reduces spare parts inventory and downtime maintenance time.

[0018] Third, the application sets spiral guide vanes in the contraction section of the circulation bypass, forms a gentle spiral flow in the throat, continuously refreshes the electrode surface boundary layer, and carries microbubbles into the top exhaust valve for discharge, thereby effectively suppressing polarization error and bubble adhesion; at the same time, the application adopts a integrated stirring-suction structure of baffle-eccentric piston-rotary tank to provide stable and pulsation-free inlet pressure for the bypass, ensures constant flow rate in the Venturi section, and makes conductivity, pH, and viscosity detection all under recommended fluid operating conditions, which significantly improves signal stability and detection repeatability. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a front view of the application; Figure 2 is a perspective structural schematic view of the application; Figure 3 is a front cross-sectional view and a local enlarged view of the application; Figure 4 is a cross-sectional view of the application along A-A; Figure 3 is a cross-sectional view of the application along A-A; Figure 5 Figure 3 is a cross-sectional perspective view and a local enlarged view of the application from a perspective angle; Figure 6 is a cross-sectional perspective view of the transfer chamber of the application; Figure 7 is an enlarged perspective view of the insulation ring and the threaded pipe of the application; Figure 8 is a cross-sectional perspective view of the insulation ring and the threaded pipe of the application; ​Figure 9 Flow chart of four tests of the present application.

[0020] In the figure: 1, premixing tank; 2, circulating bypass; 3, exhaust valve; 4, branch bypass; 5, stirring shaft; 6, electrode ring; 7, insulation ring; 8, threaded tube; 9, plug; 10, partition; 11, rotating box; 12, piston crossbar; 13, piston block; 14, liquid inlet pipe; 15, eccentric ring; 16, one-way liquid outlet; 17, lumen; 18, liquid suction hole; 19, helical guide vane; 20, lip ring; 21, pH monitoring module; 22, viscosity detection module; 23, temperature monitoring module. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0022] Please refer to Figures 1 to 9 The present application provides a technical solution: an EVCL emulsion glue mixing and proportioning device, comprising a premixing tank 1 provided with a stirring assembly, further comprising: A circulating bypass 2 in communication with the premixing tank 1, and the circulating bypass 2 is vertically installed, the inlet of the circulating bypass 2 is taken from the bottom outlet of the premixing tank 1, and the outlet returns to the premixing tank 1 in a liquid backflow manner, wherein the circulating bypass 2 forms a Venturi flow channel in turn with a contraction section, a throat section and a diffusion section; A detection unit arranged in the circulating bypass 2, and the detection unit comprises: Four ring electrodes are flushly embedded in the inner wall of the throat section, the four ring electrodes 6 comprise four electrode rings 6 arranged in turn, two electrode rings 6 on the sides are used for power supply, two electrode rings 6 on the inner side are used for pressure measurement, and an insulation ring 7 axially adjustable is further arranged between the two electrode rings 6 on the inner side.

[0023] The top end of the circulating bypass 2 is further connected with a thin tube, and the thin tube is provided with an exhaust valve 3 at the end.

[0024] In the A-phase premixing stage of the EVCL emulsion glue, deionized water, defoaming / wetting, film-forming / rheological additives are added into the premixing tank 1 and kept constant temperature; Then the internal stirring assembly is used to stir in the premixing tank 1 at low shear and slowly incorporate the EVCL emulsion; Secondly, the raw liquid in the premix is discharged through the bottom outlet of the premix tank 1 and enters into the circulating bypass 2, sequentially passes through the Venturi flow channel of the contraction section, the throat section and the diffusion section, and then returns to the premix tank 1 in the form of underflow reflux, forming a circulating flow path; In the process of circulation, the raw liquid forms a constant cross section and a stable linear velocity at the throat section, and the four electrodes rings 6 arranged in flush with the inner wall of the throat section are sequentially E1, E2, E3 and E4 along the flow direction. The outer E1 and E4 are applied with a small alternating current I by the transmitter to establish an axial electric field in the liquid, and the inner E2 and E3 are connected to a high input impedance differential amplifier to only sample the potential without current, so that the potential difference AV is read, and the conductance G=I / AV is obtained by Ohm's law, and the liquid conductivity κ=K×G can be obtained by combining the electrode constant K, so as to monitor the conductivity to determine whether the phase A is stable. It is worth mentioning that an adjustable insulation ring 7 is arranged between E2 and E3, the inner surface of which is flush with the inner wall of the throat section, forming a pure insulation straight cylinder between E2 and E3, which is used for axial micro-adjustment or step positioning to change the axial length L_eff of the insulation straight cylinder effectively exposed on the fluid side. When the insulation ring 7 is pushed downstream, L_eff increases→K increases, and vice versa. By adjusting the insulation ring 7, the optimal range window can be aligned with different formula / conductivity intervals, and after adjustment, the position / position and K corresponding table can be established by fast calibration with standard liquid, and the conductivity can be stably output according to κ=K×(I / ΔV) during operation. When the formula or working condition is changed, only the corresponding K value needs to be switched.

[0025] In one of the more preferred embodiments, an embodiment for axially adjusting the insulation ring 7 is provided. The outer wall of the circulating bypass 2 is provided with an annular groove, and a threaded pipe 8 is rotatably installed in the annular groove. The inner annular wall of the threaded pipe 8 is provided with threads, the outer wall of the insulation ring 7 is fixedly provided with a plug 9, the free end of the plug 9 is engaged with the threads of the inner annular wall of the threaded pipe 8, and the inside of the circulating bypass 2 is provided with a long groove for sliding adjustment of the plug 9, and the outer annular wall of the insulation ring 7 always isolates the long groove from the inner wall of the throat section of the circulating bypass 2.

[0026] For details, please refer to Figure 3 and Figures 7-8 When adjusting, the threaded pipe 8 is rotated to drive the insulation ring 7 to be axially adjusted by the thread cooperation between the threads of the inner annular wall of the threaded pipe 8 and the plug 9 extended from the outer wall of the insulation ring 7. The insulation ring 7 can be limited and slidably installed by means of a flat key to ensure that it can be axially adjusted by thread cooperation.

[0027] Moreover, a scale value is also arranged on the outer wall of the circulation bypass 2, and an indicating arrow is arranged on the outer wall of the threaded pipe 8, so that the rotation angle of the threaded pipe 8 and the fine adjustment distance of the insulation ring 7 can be calibrated by the position of the indicating arrow, and the corresponding different gears can also be selected.

[0028] In a further more preferred embodiment, a lip ring 20 is formed on both sides of the insulation ring 7, and a shallow annular groove is formed on the inner wall of the throat portion of the circulation bypass 2, and the lip ring 20 and the shallow annular groove are matched with each other, and the embedded groove where the insulation ring 7 is located is separated from the inner wall of the throat portion.

[0029] Referring to Figure 8 , first, since the insulation ring 7 is installed between E2 and E3, the inner groove where the insulation ring 7 is installed will inevitably destroy the continuity of the throat passage, which is a necessary cost in structure, but we can solve it by “minimizing the damage and making the flow field feel nothing”, that is, by forming a lip ring 20 on both sides of the insulation ring 7, and the two side edges of the inner groove where the insulation ring 7 is installed are provided with a shallow groove ring matched with the lip ring 20, as shown in the enlarged portion in Figure 3 , the purpose of this is to cover the inner groove with the lip ring 20, and the groove exposed in the throat passage is only part of the embedded groove ring, which is narrow and shallow enough, and the edge is rounded, so the flow field will not treat it as “steps”, but as “a thin gap”, so the influence is negligible, and the influence on the flow velocity distribution of the electrical conductivity measurement area is also negligible.

[0030] In one of the more preferred embodiments, the back half of the diffusion section of the circulation bypass 2 is connected with two branch bypasses 4, and the inlet and outlet of the two branch bypasses 4 are connected to the back half of the circulation bypass 2, and a pH monitoring module 21 and a viscosity detection module 22 are respectively installed in the two branch bypasses 4, and a temperature monitoring module 23 is also installed at the backflow port of the circulation bypass 2 and the premixing tank 1; It also includes a controller electrically connected with the detection unit, the pH monitoring module 21, the viscosity detection module 22 and the temperature monitoring module 23, and the controller is configured to generate a signal of A-phase stability based on the stability criteria of electrical conductivity, pH, viscosity and temperature.

[0031] Since the stirring time is not a “timer”, but a “result reaching stability”, the length of time depends on whether a set of stability indicators is reached, and among them, viscosity and electrical conductivity are very important, but at least the uniformity of pH and temperature is added, which is more stable and more reproducible, so the detection of the remaining three items is added on the basis of the above electrical conductivity detection; For details, please refer to Figure 2 and Figure 9, by adding pH monitoring module 21, viscosity detection module 22 and temperature monitoring module 23, the pH value, viscosity value and temperature of the original liquid can be further monitored synchronously, and the detection of the above conductivity is combined, through the synchronous detection of the four signals, the final quality of the A phase can be ensured; Wherein, the pH monitoring module 21 is a flow-through composite glass electrode, preferably a double salt bridge, a PTFE annular diaphragm and built-in, and the detection of the viscosity value is preferably a vibration type / sonotrode type online viscosity meter, which can be detected in the existing manner, but the difference lies in that the pH and viscosity are detected in the independent branch bypass 4 of each online circuit, avoiding the high shear and electric field area of the venturi throat, not disturbing the electric field measurement flow field, and avoiding the cross influence of pH and viscosity due to flow rate / bubble / pressure pulsation, improving batch repeatability.

[0032] Moreover, the pH branch can be provided with tangential liquid inlet + top gas discharge to form a "static liquid window" to inhibit bubble adhesion and liquid contact drift, and the viscosity branch maintains full pipe small flow to make the vibration type / sonotrode type sensor work within the recommended flow rate range, reducing the interference of cavitation and bubbles on resonance.

[0033] In a further more preferred embodiment, the inner wall of the contraction section of the circulation bypass 2 is further formed with a spiral guide vane 19 in a spiral design, and the A phase is guided by the spiral guide vane 19 to form a spiral liquid flow at the throat section of the circulation bypass 2.

[0034] Specifically refer to Figure 5 The design of the spiral guide vane 19 can form a "gentle spiral flow" when the liquid flow passes through the contraction section, which can not only refresh the boundary layer, that is, the circumferential velocity induced by the spiral + speed-up → wall shear, so that the concentration difference layer near E2 / E3 is continuously washed away, and the concentration difference boundary layer near the electrode is continuously refreshed by wall shear, thereby reducing the risk of "polarization sample" error. It is worth mentioning that a certain length of rectification transition section is reserved between the contraction section and the throat to avoid excessive spiral shear. Moreover, it can also drive away micro-bubbles, that is, the spiral + speed-up can thin large bubbles, which are more easily discharged by the exhaust valve 3 of the top-mounted vertical cavity after entering the diffusion section.

[0035] In one of the more preferred embodiments, a stirring mode and an embodiment capable of stably injecting the premixed liquid into the circulation bypass 2 and circulating are provided; The stirring assembly includes a partition plate 10 fixed to the premixing tank 1 near the lower inner wall, and the partition plate 10 divides the premixing tank 1 into an upper premixing cavity and a lower transfer cavity, the top of the partition plate 10 is provided with a rotatable stirring shaft 5, and the outer wall of the stirring shaft 5 is provided with a plurality of stirring blades, and the liquid inlet of the circulation bypass 2 is communicated with the transfer cavity.

[0036] The inner bottom of the premixing tank 1 is provided with a rotating box 11 driven to rotate by a servo motor, the inner wall of the rotating box 11 is slidably provided with a piston block 13, the inside of the piston block 13 is fixedly provided with a piston cross rod 12, the two ends of the piston cross rod 12 pass through the two sides of the rotating box 11 and are sealingly and slidably connected with the outer walls of the two sides of the rotating box 11, the bottom of the partition plate 10 is fixedly provided with an eccentric ring 15 designed eccentrically, the two ends of the piston cross rod 12 can alternately contact the inner wall of the eccentric ring 15, the two sides of the rotating box 11 are provided with one-way liquid discharge ports 16, the top of the rotating box 11 is communicated with a liquid inlet pipe 14, the liquid inlet pipe 14 is provided with a one-way liquid inlet valve, the liquid inlet pipe 14 passes through the top of the partition plate 10 and is fixedly and coaxially arranged with the bottom of the stirring shaft 5, the inside of the stirring shaft 5 is provided with a lumen 17 communicated with the liquid inlet pipe 14, and the outer wall of the stirring shaft 5 is also provided with a plurality of liquid suction holes 18 of different heights and communicated with the lumen 17.

[0037] The two ends of the piston cross rod 12 are rotatably provided with rollers.

[0038] Specifically refer to Figures 4-6 In the premixing stage, the rotating box 11 is driven to rotate by the servo motor, and at the same time, the liquid inlet pipe 14 at the top end of the rotating box 11 drives the stirring shaft 5 to rotate synchronously, so as to use the stirring blades to stir the raw liquid in the premixing cavity; At the same time, the rotation of the rotating box 11 also drives the piston cross rod 12 to rotate synchronously, and because of the eccentric design of the eccentric ring 15, the two ends of the piston cross rod 12 alternately contact the inner wall of the eccentric ring 15 in the process of rotating the rotating box 11 and the piston cross rod 12, so as to drive the piston cross rod 12 to reciprocatingly slide in the inside of the rotating box 11 with the rotation of the rotating box 11, and further drive the piston block 13 to reciprocatingly slide in the rotating box 11, utilize the pressure change in the space on the two sides of the piston block 13, suck the emulsion in the premixing cavity through the liquid inlet pipe 14 and then discharge it to the transfer cavity below through the one-way liquid discharge port 16, and then enter the circulating bypass 2 after the transfer cavity is filled, and then return to the premixing cavity from the liquid below, complete the circulation of the emulsion, so as to complete the above-mentioned four detections in the process of circulation; It is worth mentioning that the alternating suction and extrusion in the space on the two sides of the piston block 13 can make the emulsion continuously flow into the transfer cavity, which provides a relatively stable pressure and flow rate for the subsequent detection, improves the accuracy of the detection result, and the rotation of the piston cross rod 12 and the liquid extrusion of the one-way liquid discharge port 16 can fully mix the emulsion raw liquid in the transfer cavity, so as to avoid the stratification phenomenon and not be disturbed by the "local concentration difference" of the feeding port.

[0039] A mixing method of an EVCL emulsion glue mixing and proportioning equipment, comprising the following steps: S1, in the premixing stage of phase A, first premixing and stirring the raw liquid in the premixing tank 1 by the internal stirring assembly; S2, secondly, the raw liquid in the premixing is discharged from the bottom outlet of the premixing tank 1 and enters the circulating bypass 2, sequentially passes through the Venturi flow channel of the contraction section, the throat section and the diffusion section, and then returns to the premixing tank 1 in the form of liquid underflow to form a circulating flow path; S3, wherein, in the process of circulation, the raw liquid forms a constant cross section and a stable linear velocity at the throat section, and the four electrode rings 6 arranged in flush with the inner wall of the throat section are E1, E2, E3 and E4 in sequence along the flow direction, the outer E1 and E4 are applied with a small alternating current I by the transmitter to establish an axial electric field in the liquid, and the inner E2 and E3 are connected to a high input impedance differential amplifier to only sample the potential without current, so that the potential difference ΔV is read, the conductance G=I / ΔV is obtained by Ohm's law, and the liquid conductivity κ=K×G is obtained by combining the electrode constant K, so as to monitor the conductivity and determine whether phase A is "stable"; S4, wherein an adjustable insulation ring 7 is arranged between E2 and E3, the inner surface of the insulation ring 7 is flush with the inner wall of the throat section, and a section of pure insulation straight cylinder is formed between E2 and E3, which is used for changing the axial length L_eff of the section of pure insulation straight cylinder effectively "exposed" on the fluid side by axial micro-movement or step positioning, when the insulation ring 7 is pushed downstream, L_eff increases→K increases, and vice versa K decreases, by the fine adjustment of the insulation ring 7, the best range window can be aligned with different formula / conductivity intervals, and after adjustment, the position / position is calibrated with a standard liquid, and a corresponding table of K is established, κ=K×(I / ΔV) is obtained during operation, and the conductivity can be stably output, and when the formula or working condition is changed, only the corresponding K value needs to be switched.

[0040] The standard parts used in the embodiment can be directly purchased from the market, and the non-standard structural parts according to the description and drawings can also be directly processed according to the existing technical knowledge without any doubt, and the connection mode of each part adopts the mature conventional means in the existing technology, and the machinery, parts and equipment adopt the conventional models in the existing technology, so the specific description is not made here.

[0041] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. An EVCL emulsion mixing and proportioning device, comprising a premixing tank (1) equipped with a stirring assembly, characterized in that, Also includes: A circulation bypass (2) is connected to the premix tank (1), and the circulation bypass (2) is installed vertically. The inlet of the circulation bypass (2) is taken from the bottom outlet of the premix tank (1), and the outlet returns to the premix tank (1) in the form of submerged reflux. The circulation bypass (2) sequentially forms a venturi channel with a contraction section, a throat, and a diffusion section. The detection unit is located within the loop bypass (2), and the detection unit includes: Four-ring electrodes are flush with the inner wall of the throat. The four-ring electrodes include four electrode rings (6) arranged in sequence. The two electrode rings (6) on both sides are used for energizing, and the two electrode rings (6) on the inner side are used for pressure taking. An axially adjustable insulating ring (7) is also provided between the two electrode rings (6) on the inner side.

2. The EVCL emulsion mixing and proportioning equipment according to claim 1, characterized in that: The outer wall of the circulation bypass (2) is provided with an annular groove, and a threaded tube (8) is rotatably installed in the annular groove. The inner annular wall of the threaded tube (8) is provided with threads. The outer wall of the insulating ring (7) extends and is fixed with a pin (9). The free end of the pin (9) engages with the thread of the inner annular wall of the threaded tube (8). The inside of the circulation bypass (2) is provided with a long groove for the pin (9) to slide and adjust. The outer annular wall of the insulating ring (7) always isolates the long groove from the throat inner wall of the circulation bypass (2).

3. The EVCL emulsion mixing and proportioning equipment according to claim 2, characterized in that: Both sides of the insulating ring (7) are formed with lip rings (20), and the inner wall of the throat of the circulation bypass (2) is provided with a shallow ring groove. The lip ring (20) fits into the shallow ring groove and separates the groove where the insulating ring (7) is located from the inner wall of the throat.

4. The EVCL emulsion mixing and proportioning equipment according to claim 1, characterized in that: The latter half of the diffusion section of the circulation bypass (2) is connected to two branch bypasses (4), and the inlet and outlet of the two branch bypasses (4) are connected to the latter half of the circulation bypass (2). A pH monitoring module (21) and a viscosity detection module (22) are installed in the two branch bypasses (4), and a temperature monitoring module (23) is also installed at the reflux port between the circulation bypass (2) and the premix tank (1). It also includes a controller electrically connected to the detection unit, pH monitoring module (21), viscosity detection module (22) and temperature monitoring module (23), and the controller is configured to generate a stable A-phase signal based on stability criteria of conductivity, pH, viscosity and temperature.

5. The EVCL emulsion mixing and proportioning equipment according to claim 1, characterized in that: The top of the circulation bypass (2) is also connected to a thin tube, and an exhaust valve (3) is provided at the end of the thin tube.

6. The EVCL emulsion mixing and proportioning equipment according to claim 1, characterized in that: The inner wall of the contraction section of the circulation bypass (2) is also formed with a spiral guide vane (19) with a spiral design, and the A phase is guided by the spiral guide vane (19) to form a spiral liquid flow in the throat section of the circulation bypass (2).

7. The EVCL emulsion mixing and proportioning equipment according to claim 1, characterized in that: The stirring assembly includes a partition (10) fixed to the lower inner wall of the premix tank (1), and the partition (10) divides the premix tank (1) into an upper premix chamber and a lower transfer chamber. A rotatable stirring shaft (5) is installed on the top of the partition (10), and several stirring blades are installed on the outer wall of the stirring shaft (5). The inlet of the circulation bypass (2) is connected to the transfer chamber.

8. The EVCL emulsion mixing and proportioning equipment according to claim 7, characterized in that: The premix tank (1) has a rotating box (11) installed at its inner bottom, driven by a servo motor. A piston block (13) is slidably installed on the inner wall of the rotating box (11). A piston rod (12) is fixedly fixed through the inside of the piston block (13). The two ends of the piston rod (12) protrude from both sides of the rotating box (11) and are slidably sealed to the outer walls of both sides of the rotating box (11). An eccentric ring (15) with an eccentric design is fixed at the bottom of the partition plate (10), and the two ends of the piston rod (12) can alternately interact with the eccentric ring (15). The inner wall of the rotating box (11) is in contact with the inner wall of the rotating box (12). One-way drain ports (16) are provided on both sides of the rotating box (11). The top of the rotating box (11) is connected to the inlet pipe (14), and a one-way inlet valve is installed in the inlet pipe (14). The top of the inlet pipe (14) passes through the partition (10) and is coaxially fixed to the bottom of the stirring shaft (5). The inside of the stirring shaft (5) is provided with a cavity (17) that communicates with the inlet pipe (14). The outer wall of the stirring shaft (5) is also provided with multiple suction holes (18) of different heights that communicate with the cavity (17).

9. The EVCL emulsion mixing and proportioning equipment according to claim 8, characterized in that: Both ends of the piston rod (12) are rotatably mounted with rollers.

10. A mixing method for an EVCL emulsion mixing and proportioning device according to any one of claims 1-9, characterized in that, Includes the following steps: S1. In the A-phase premixing stage, the original liquid in the premixing tank (1) is first premixed and stirred by the internal stirring components. S2. Next, the raw liquid in the premix is ​​discharged from the bottom outlet of the premix tank (1) and enters the circulation bypass (2). After passing through the Venturi channels of the contraction section, throat and diffusion section in sequence, it returns to the premix tank (1) in the form of submerged reflux to form a circulation path. S3, In the process of circulation, the original liquid forms a constant cross section and a stable linear velocity in the throat. At the same time, four electrode rings (6) are arranged flush with the inner wall of the throat. They are E1, E2, E3 and E4 in sequence along the flow direction. The outer E1 and E4 are given a small AC current I by the transmitter to establish an axial electric field in the liquid. The inner E2 and E3 are connected to a high input impedance differential amplifier. Only the potential is sampled and not the current is sampled. The potential difference ΔV is read. The conductivity G=I / ΔV is obtained from the Ohm relationship. Combined with the electrode constant K, the liquid conductivity can be calculated: κ=K×G. The purpose of monitoring the conductivity and determining whether phase A has been "stable" is achieved. S4. An adjustable insulating ring (7) is set between E2 and E3. Its inner surface is flush with the inner wall of the throat, forming a section of pure insulating straight cylinder between E2 and E3. Through axial micro-movement or segmented positioning, the axial length L_eff of this insulating straight cylinder that is effectively "exposed" on the fluid side is changed. When the insulating ring (7) moves downstream, L_eff increases → K increases, and in the opposite direction, K decreases. Through the fine adjustment of the insulating ring (7), the optimal range window can be aligned with different formulations / conductivity ranges. After adjustment, it can be quickly calibrated with standard liquid to establish a correspondence table between position / range and K. During operation, the conductivity can be stably output according to κ=K×(I / ΔV). When changing the formulation or operating condition, it is only necessary to switch to the corresponding K value.

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