A method and device for continuously and stably adding a poorly soluble hydrophobic organic substance into an aqueous phase system

Abstract

The present application belongs to the technical field of environmental pollution control, and particularly relates to a continuous and stable adding method and device for a poorly soluble hydrophobic organic substance in an aqueous phase system. The target substance is dissolved in a volatile organic solvent to form a stock solution, or an organic solution of the target substance is used as a starting material, quantitatively added to a film forming container, and evaporated to form a film. Then, an aqueous phase medium is added and dispersed by ultrasonic waves to obtain a uniform dispersed phase stock solution. During the adding process, continuous stirring is performed to keep the suspension, and a metering pump is used to pump the target aqueous phase system at a set flow rate or period, while mechanical stirring is performed for cyclic mixing to reduce the local concentration gradient. Under the premise of reducing the interference of a co-solvent and a surfactant, the present application realizes stable and reproducible adding of a poorly soluble hydrophobic organic substance, and is suitable for reactor exposure and environmental water body simulation.

Description

Technical Field

[0001] This invention belongs to the field of environmental pollution control technology, specifically relating to a method and apparatus for the continuous and stable addition of sparingly soluble hydrophobic organic compounds in an aqueous system. Background Technology

[0002] Insoluble hydrophobic organic compounds typically have low solubility in water. Upon entering the aqueous phase, they are prone to adhesion to walls, aggregation, stratification, or the formation of transiently high concentrations in localized areas, resulting in significant discrepancies between the nominal dosage and actual exposure conditions. In activated sludge reactors, environmental water body simulation devices, ecotoxicological exposure systems, and pollution migration and transformation studies, unstable dosage methods often lead to large concentration fluctuations within the system, poor repeatability, and insufficient comparability between different experimental batches.

[0003] In existing technologies, common treatment methods include: using a large amount of co-solvent to directly introduce the target analyte into the aqueous phase, improving dispersibility with surfactants, or using a one-time shock dosing method to increase the nominal loading. While these methods can introduce the target analyte into the system in a short time, they are prone to the following problems: First, a large amount of co-solvent or surfactant can alter the interfacial properties, microbial response, or ecotoxicological effects of the system; second, a one-time shock dosing can easily create a short-term concentration peak, which is not conducive to simulating continuous exposure or continuous influent conditions; third, it is difficult to maintain a consistent dosing process across multiple reactors or multiple operating cycles.

[0004] Therefore, there is a need for an engineering method and a matching device that can stably transfer sparingly soluble hydrophobic organic compounds to the aqueous phase without relying on large amounts of co-solvents or surfactants and can be continuously, quantitatively, and reproducibly added. Summary of the Invention

[0005] The purpose of this invention is to provide a method and apparatus for the continuous and stable addition of sparingly soluble hydrophobic organic compounds in an aqueous system, so as to solve the problems of unstable addition, large local concentration gradient, poor repeatability, and large interference from co-solvents / surfactants in the prior art.

[0006] The method for continuous and stable addition of sparingly soluble hydrophobic organic compounds in an aqueous system provided by this invention comprises the following steps:

[0007] S1. Dissolve the sparingly soluble hydrophobic organic compound in a volatile organic solvent to obtain a stock solution, or use an organic solution of the target compound as the starting material for the stock solution;

[0008] S2. Add a quantitative volume of the stock solution to the film-forming container to allow the volatile organic solvent to evaporate, thereby forming a residual film or residual layer on the inner wall and / or bottom of the film-forming container.

[0009] S3. Add an aqueous medium to the film-forming container and perform ultrasonic dispersion on the film-forming container to convert the residual film or residual layer into a homogeneous dispersed mother liquor.

[0010] S4. During the addition process, the dispersed mother liquor is continuously stirred to keep the dispersed mother liquor in a suspended and dispersed state.

[0011] S5. The dispersed mother liquor is pumped into the target aqueous phase system in a continuous flow or pulse flow manner using a metering pump;

[0012] S6. Before, during and / or after addition, the target aqueous phase system is mechanically stirred and circulated to reduce the local concentration gradient and improve addition stability.

[0013] Furthermore:

[0014] In step S1, the volatile organic solvent is one of cyclohexane, n-hexane, isooctane, dichloromethane, or a mixture thereof.

[0015] In step S2, the volatile organic solvent is volatilized under conditions of ventilation, inert gas purging, depressurization, heating, or a combination thereof, until the residual solvent in the film-forming container is below a preset threshold.

[0016] In step S3, the aqueous medium is ultrapure water, deionized water, buffer solution, simulated environmental water, simulated wastewater, actual influent, or a combination thereof, and preferably is the same as or equivalent to the water matrix of the target aqueous system.

[0017] In step S3, the ultrasonic dispersion time is 1-60 min, preferably 1-10 min, and the ultrasonic power is 50-800 W. The ultrasonic dispersion is performed using either an ultrasonic water bath or probe ultrasound. The nominal concentration of the dispersed phase mother liquor is preferably 0.2-2000 μg / L, more preferably 1-200 μg / L.

[0018] In step S4, the dispersed mother liquor is continuously stirred. The continuous stirring method is one of magnetic stirring, top mechanical stirring, or circulating reflux stirring, and the stirring speed is 50-1000 r / min.

[0019] In step S5, the metering pump is one of a peristaltic pump, a plunger pump, or a diaphragm metering pump. The dosing method is either quantitative dosing according to the reaction cycle or continuous dosing according to a set flow rate.

[0020] In step S5, the target aqueous phase system is any one of a sequencing batch reactor, a continuous flow reactor, a batch reactor, or an environmental water body simulation device. The nominal loading of the target aqueous phase system is preferably 10-10000 ng / L, more preferably 50-1000 ng / L; when expressed as a nominal target concentration, the nominal target concentration is preferably 10-1000 ng / L, more preferably 50-500 ng / L.

[0021] In step S5, the injection volume per single session or per cycle is 0.5%-5% of the effective volume of the target aqueous phase system, preferably 1%-3%. The dispersed phase mother liquor can be added synchronously or sequentially to multiple parallel target aqueous phase systems via a distributor or multi-way switching valve.

[0022] In step S6, the duration of the circulating mixing of the target aqueous system is not less than 5 minutes, preferably not less than 10 minutes.

[0023] Furthermore:

[0024] The aforementioned continuous and stable dosing includes both continuous flow dosing in the strict sense and pulsed or intermittent quantitative dosing implemented according to a preset cycle. This is as long as the dosing amount, dosing sequence, and mixing process within the target system are controllable.

[0025] The nominal concentration Cm of the dispersed phase mother liquor can be estimated by the following formula:

[0026] Cm = (Cs × Va) / Vw,

[0027] Where Cs is the concentration of the stock solution or working solution, Va is the volume of the stock solution or working solution added to the film-forming container, and Vw is the volume of the aqueous medium added to the film-forming container.

[0028] The concentration of the stock solution is preferably 10-10000 μg / mL, more preferably 100-1000 μg / mL. When improved pipetting accuracy is required, a working solution can be further prepared from the stock solution, the concentration of which is preferably 1-100 μg / mL, more preferably 5-20 μg / mL.

[0029] Given a single injection volume Vi or a unit cycle injection volume, or a given pump flow rate Q and injection time t, the nominal injection mass Md per unit time or per injection into the target aqueous system can be estimated by the following formula:

[0030] Md = Cm × Vi = Cm × Q × t.

[0031] When the effective volume of the target aqueous system is Vr, the corresponding nominal loading amount Lt and nominal target concentration Ct can be estimated by the following formula:

[0032] Lt = Md / Vr, Ct = Md / Vr.

[0033] When the practical saturation concentration of the target substance under the corresponding aqueous matrix, temperature and mixing conditions is lower than the Ct, the exposure level is preferably expressed using Lt.

[0034] This invention also provides a device for the continuous and stable addition of sparingly soluble hydrophobic organic compounds in an aqueous system for implementing the above method, comprising a film-forming container 1, a evaporation unit 2, an ultrasonic dispersion unit 3, a stirring and suspension unit 4, a metering pump and control unit 5, a dosing pipeline 6, and a mixing unit 7; wherein:

[0035] The evaporation unit 2 is configured to evaporate the stock liquid in the film-forming container 1 to form a residual film or residual layer in the film-forming container 1.

[0036] The ultrasonic dispersion unit 3 is configured to perform ultrasonic dispersion on the film-forming container 1 after the addition of the aqueous medium to obtain the dispersed phase mother liquor.

[0037] The stirring and suspension unit 4 is configured to maintain the dispersion of the mother liquor during the addition process;

[0038] The metering pump and control unit 5 is connected to the liquid outlet of the film-forming container 1, and is connected to the target aqueous phase system 8 through the dosing pipeline 6;

[0039] The mixing unit 7 is disposed within the target aqueous system 8 or in a circulation loop connected to the target aqueous system 8, and is used to mechanically stir or circulate the target aqueous system 8.

[0040] Furthermore:

[0041] The evaporation unit 2 includes at least one of an inert gas purging port, a ventilation port, a pressure reducing port, or a heating base.

[0042] The ultrasonic dispersion unit 3 is an ultrasonic water bath or an ultrasonic probe, and the film-forming container 1 is a solvent-resistant glass bottle or a polytetrafluoroethylene-lined container.

[0043] The stirring and suspension unit 4 is a magnetic stirrer or a top-mounted stirrer, and is equipped with an anti-volatile sealing cap and / or an anti-contamination filter membrane.

[0044] The metering pump and control unit 5 are linked to the target aqueous system 8 for cycle-based control, so as to trigger the addition periodically or adjust the addition amount according to the feedback signal.

[0045] The end of the dosing pipeline 6 is equipped with a check valve, distributor or multi-way switching valve 9 to achieve single reactor dosing or simultaneous / sequential dosing of multiple reactors.

[0046] Compared with the prior art, the present invention has at least the following beneficial effects:

[0047] (1) High addition stability. Through the process chain of quantitative film formation, evaporation, ultrasonic dispersion, and suspension addition, sparingly soluble hydrophobic organic matter can be converted into a dispersible mother liquor that can be measured and continuously transported, reducing the randomness and instantaneous peak caused by one-time shock addition.

[0048] (2) Minimal interference with the system. The target substance has already undergone phase transfer through solvent evaporation before entering the target aqueous system, which can significantly reduce the interfacial disturbance, microbial inhibition or ecotoxicological deviation caused by the direct entry of the cosolvent into the target system. In the preferred embodiment, no additional surfactant needs to be added.

[0049] (3) High reproducibility. The metering pump and control unit can be used to standardize the control of the injection flow rate, injection cycle, injection duration and multi-reactor allocation strategy, thereby improving the consistency between different experimental cycles, different operators and different parallel reactors.

[0050] (4) Wide range of applications. This method and apparatus are applicable to sequencing batch reactors, continuous flow reactors and batch reactors, as well as to scenarios that require stable aqueous phase loading, such as environmental water body simulation, ecological exposure and pollution migration and transformation studies. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of the structure of the device for continuous and stable addition of sparingly soluble hydrophobic organic compounds in an aqueous system according to the present invention.

[0052] Figure 2 This is a flowchart of the method for continuous and stable addition of sparingly soluble hydrophobic organic compounds in an aqueous system according to the present invention.

[0053] In the diagram, the following are the markings: 1 is the film-forming container, 2 is the evaporation unit, 3 is the ultrasonic dispersion unit, 4 is the stirring and suspension unit, 5 is the metering pump and control unit, 6 is the dosing pipeline, 7 is the mixing unit, 8 is the target aqueous phase system, and 9 is the distributor / multi-way switching valve (optional). Detailed Implementation

[0054] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. For those skilled in the art, equivalent substitutions or conventional changes made to process steps, device connection relationships, parameter ranges, and control strategies without departing from the concept of the present invention should all fall within the scope of protection of the present invention.

[0055] The term "poorly soluble hydrophobic organic matter" as used in this invention includes, but is not limited to, polycyclic aromatic hydrocarbons, halogenated aromatic hydrocarbons, chlorinated pesticides, polychlorinated biphenyls, brominated flame retardants, chlorinated flame retardants, hydrophobic plasticizers, and other organic pollutants with low solubility in water that readily separate into layers, adhere to walls, or form locally high concentrations in the aqueous phase. The volatile organic solvent is preferably an organic solvent that is easily subsequently removed and can effectively dissolve the target analyte, such as cyclohexane, n-hexane, isooctane, dichloromethane, or mixtures thereof.

[0056] The preferred film-forming container is a solvent-resistant glass container, a brown glass bottle, or a container with a polytetrafluoroethylene liner. The terms "complete evaporation" or "evaporation to dryness" can be determined by the constant mass method, the set time method, the inert gas purging method, the reduced pressure evaporation method, or the residual solvent detection method. As long as the residual solvent is below the preset threshold and does not cause substantial interference to the target aqueous phase system, it is acceptable.

[0057] Example 1, Preparation of dispersed phase mother liquor

[0058] The target sparingly soluble hydrophobic organic compound is dissolved in a volatile organic solvent to obtain a stock solution. The concentration of the stock solution can be preset according to the nominal loading amount of the target and the operating range of the subsequent metering pump. A fixed volume of the stock solution is added to the film-forming container 1, and the solvent is evaporated by natural ventilation, inert gas purging, depressurization, gentle heating, or a combination thereof, so that the target compound forms a residual film or residual layer on the inner wall and / or bottom of the film-forming container 1. Subsequently, ultrapure water, buffer solution, simulated environmental water, or an aqueous matrix identical to the target system is added to the film-forming container 1, and ultrasonic treatment is performed for 5-60 minutes using the ultrasonic dispersion unit 3 to form a homogeneous dispersed phase mother liquor. After the dispersed phase mother liquor is formed, the stirring and suspension unit 4 is started to continuously stir magnetically, top-mounted stir, or circulate back to prevent stratification, adhesion, or sedimentation.

[0059] Example 2, Reactor Dosing and Mixing

[0060] like Figure 1 As shown, the dispersed phase mother liquor in film-forming container 1 is connected to the dosing pipeline 6 via a metering pump and control unit 5. The pump flow rate, dosing time, and dosing cycle are set according to the effective volume of the target reactor, the target concentration, or the nominal loading rate. After starting the metering pump and control unit 5, the dispersed phase mother liquor enters the target aqueous phase system 8 in a continuous or pulsed flow manner. To reduce local concentration gradients, mechanical stirring is performed before, during, and / or after dosing via a mixing unit 7 located in the target aqueous phase system 8, or circulation mixing is performed via an external circulation pump. The mixing time is set according to the reactor volume, compound structure, and device characteristics, generally within the range of 1-20 minutes.

[0061] Example 3: Simultaneous addition of feed to multiple reactors

[0062] When multiple scenarios require parallel exposure or parallel comparison of multiple reactors, a distributor or multi-way switching valve 9 can be installed at the end of the dosing pipeline 6. The metering pump and control unit 5 simultaneously or sequentially add multiple target aqueous systems 8 according to a set program. By using a unified source of mother liquor, unified pump control parameters, and a unified mixing strategy, the consistency of dosing and the comparability of experiments among multiple sets of equipment can be improved.

[0063] Example 4: Feedback-linkage control

[0064] The metering pump and control unit 5 can be linked to the operating cycle of the target aqueous system 8, triggering dosing according to the influent stage, reaction stage, or aeration / stirring stage. The dosing rate and dosing rhythm can also be adjusted based on liquid level, flow rate, turbidity, online concentration, operating time, or other feedback signals. This implementation is particularly suitable for continuous flow reactors, sequencing batch reactors, and simulation systems requiring long-term stable exposure.

[0065] It should be noted that this invention is not limited to specific target pollutants, specific container sizes, specific stirrer types, or specific metering pump types. Any equivalent technical solution that employs a volatile organic solvent to first form a quantitatively quantifiable stock solution of a poorly soluble hydrophobic organic compound, followed by film-forming evaporation, ultrasonic dispersion in the aqueous phase, continuous suspension, metering pump addition, and enhanced mixing of the target system to achieve continuous and stable addition should fall within the protection scope of this invention.

[0066] Example 5: Continuous and stable addition of chlorinated paraffin in a 3 L sequencing batch reactor

[0067] This embodiment uses chlorinated paraffin as a representative poorly soluble hydrophobic organic compound to demonstrate the effectiveness of the method of the present invention at low ng·L⁻¹. -1 The application in a phase-aqueous system is described below. Six parallel laboratory-scale sequencing batch reactors (SBRs) were used, each with an effective volume of 3 L and a volume exchange ratio of 50%, meaning that the influent and effluent volumes per cycle were both 1.5 L. Sampling ports were installed on the outer wall of the reactors, and top-mounted mechanical stirrers and bottom-mounted microporous aerators were installed internally. The SBR cycle was set as follows: 10 min influent, 2 h anaerobic, 2.5 h aerobic, 2 h anoxic, 20 min sedimentation, 2 min effluent, and 1 h idle. The influent pH was adjusted to 7.5 ± 0.3, and the dissolved oxygen (DO) was maintained at 3.0–5.0 mg / L during the aerobic phase. All reactors were run to steady state before exposure.

[0068] The test compounds were short-chain chlorinated paraffins (SCCP, C10-C13), medium-chain chlorinated paraffins (MCCP, C14-C17), and long-chain chlorinated paraffins (LCCP, C24). SCCP and MCCP used 100 μg / mL cyclohexane stock solutions, while LCCP used 1000 μg / mL cyclohexane stock solutions. To ensure consistent operation, the stock solutions were diluted with cyclohexane to a working solution of 10 μg / mL. Before each addition, 60 μL of working solution (corresponding to 0.60 μg of the test compound) was accurately added to a glass film-forming vial with a PTFE-lined cap. The vial was then placed in a fume hood and allowed to evaporate at room temperature for 10-20 min until no visible solvent droplets remained, allowing the test compound to form a residual film or layer on the vial wall and / or bottom.

[0069] Subsequently, 50 mL of deionized water or an aqueous medium equivalent to the target aqueous system is added to the film-forming bottle. The mixture is first treated with an ultrasonic water bath for 2-3 minutes, followed by magnetic stirring for at least 10 minutes to form a homogeneous dispersed mother liquor. Based on 0.60 μg of the test sample and 50 mL of aqueous medium, the nominal concentration of the dispersed mother liquor is approximately 12 μg / L. The mother liquor is continuously stirred and suspended throughout the addition process. Addition is performed once per SBR operating cycle. After the influent is finished or before the anaerobic stage begins, the film-forming bottle is connected to a short-range peristaltic pump. Under continuous stirring, 50 mL of the mother liquor is pumped into the corresponding SBR reactor in a single operation. The 50 mL single injection volume accounts for approximately 1.67% of the effective volume of the 3.0 L target aqueous system, without additional water pumping correction. Thus, each reactor obtains 0.60 μg of the test sample per injection, corresponding to a nominal final concentration / load of 200 ng / L.

[0070] Example 6: Continuous exposure results using the method of the present invention

[0071] Under the above conditions, the control group and the SCCP, MCCP, and LCCP treatment groups were run continuously for 4 weeks. The results showed that after addition using the method of this invention, no significant organic solvent introduction, large-area oil film on the liquid surface, or short-term instability caused by addition were observed throughout the entire exposure period. The COD removal rate of each treatment group remained above 97%, indicating that the method of this invention did not significantly interfere with the basic mixing of the system and the removal of heterotrophic organic matter under low-dose continuous addition conditions.

[0072] Furthermore, chlorinated paraffins of different chain lengths exhibited distinguishable chain length-dependent effects under the same dosing method and nominal loading. MCCP group effluent NH4 +The average nitrogen concentration increased from 1.32 mg / L before exposure to 3.48 mg / L, corresponding to a decrease in removal rate from 97% to 89%. The average TN removal rate of the LCCP group decreased from approximately 80% to 71%, and the average effluent TN increased to 10.79 mg / L. The average TP removal rate of the LCCP group decreased from approximately 91% to 78%. The phosphorus removal performance of the SCCP group remained generally stable, with a TP removal rate of approximately 88% and an average effluent TP of approximately 1.07 mg / L. The MCCP group achieved a TP removal rate as high as 97% in the later stages of exposure.

[0073] The above results demonstrate that the method of the present invention can not only achieve stable and quantitative addition of poorly soluble hydrophobic organic compounds without the addition of additional surfactants, but also establish repeatable and distinguishable low-dose continuous exposure conditions in multiple parallel reactors, providing a comparable experimental basis for subsequent process response, microecological effects and migration and transformation studies.

[0074] Example 7: Parallel Application of Multiple Reactors

[0075] Using the same batch of working solution, the same mother liquor preparation steps, the same pump control parameters, and the same reactor mixing strategy, multiple parallel SBR reactors were simultaneously or sequentially added. Before exposure, the TN and TP distributions of the effluent from each reactor were similar, indicating good baseline comparability among the parallel reactors under the same operating conditions. After entering the continuous addition stage, the chlorinated paraffin treatment groups with different chain lengths showed stable differentiation while maintaining the same target loading, indicating that the method of this invention is suitable for parallel experiments with multiple reactors and long-term continuous exposure scenarios, and has good repeatability and scalability.

Claims

1. A method for the continuous and stable addition of a sparingly soluble hydrophobic organic compound to an aqueous system, characterized in that, The specific steps are as follows: S1. Dissolve the sparingly soluble hydrophobic organic compound in a volatile organic solvent to obtain a stock solution, or use an organic solution of the target compound as a stock solution; S2. Add a quantitative volume of the stock solution to the film-forming container to allow the volatile organic solvent to evaporate, thereby forming a residual film or residual layer on the inner wall and / or bottom of the film-forming container. S3. Add an aqueous medium to the film-forming container and perform ultrasonic dispersion on the film-forming container to convert the residual film or residual layer into a homogeneous dispersed mother liquor. S4. During the addition process, the dispersed mother liquor is continuously stirred to keep the dispersed mother liquor in a suspended and dispersed state. S5. The dispersed phase mother liquor is added to the target aqueous phase system in a continuous flow or pulsed flow manner using a metering pump; S6. Before, during and / or after addition, the target aqueous phase system is mechanically stirred and circulated to reduce the local concentration gradient and improve addition stability.

2. The continuous and stable dosing method according to claim 1, characterized in that, In step S1, the concentration of the stock solution is preferably 10-10000 μg / mL; the volatile organic solvent is one of cyclohexane, n-hexane, isooctane, dichloromethane, or a mixture thereof.

3. The continuous and stable dosing method according to claim 1, characterized in that, The evaporation of volatile organic solvents in step S2 is carried out under conditions of ventilation, inert gas purging, depressurization, heating, or a combination thereof, until the residual solvent in the film-forming container is below a preset threshold.

4. The continuous and stable dosing method according to claim 1, characterized in that, In step S3: The aqueous medium is ultrapure water, deionized water, buffer solution, simulated environmental water, simulated wastewater, actual influent, or a combination thereof; The ultrasonic dispersion time is 1-60 min, and the ultrasonic power is 50-800 W; the ultrasonic dispersion is performed using either an ultrasonic water bath or probe ultrasound, and the nominal concentration of the dispersed phase mother liquor is 0.2-2000 μg / L.

5. The continuous and stable dosing method according to claim 1, characterized in that, The continuous stirring of the dispersed mother liquor in step S4 can be carried out by one of magnetic stirring, top mechanical stirring or circulating reflux stirring, with a stirring speed of 50-1000 r / min.

6. The continuous and stable dosing method according to claim 1, characterized in that, In step S5: The metering pump is one of a peristaltic pump, a plunger pump, or a diaphragm metering pump; The addition method is either quantitative addition according to the reaction cycle or continuous addition according to a set flow rate; The target aqueous phase system is any one of a sequencing batch reactor, a continuous flow reactor, a batch reactor, or an environmental water body simulation device; The nominal loading amount of the target aqueous phase system is 10-10000 ng / L; when expressed as a nominal target concentration, the nominal target concentration is 10-1000 ng / L; the injection volume per single or per cycle is 0.5%-5% of the effective volume of the target aqueous phase system.

7. The continuous and stable dosing method according to claim 1, characterized in that, The duration of the circulating mixing of the target aqueous phase system in step S6 shall not be less than 5 minutes.

8. The continuous and stable dosing method according to claim 1, characterized in that, In step S5, the dispersed phase mother liquor is added synchronously or sequentially to multiple parallel target aqueous phase systems via a distributor or multi-way switching valve.

9. A device for the continuous and stable addition of a sparingly soluble hydrophobic organic compound in an aqueous system for performing the method according to any one of claims 1-8, characterized in that, It includes a film-forming container (1), a evaporation unit (2), an ultrasonic dispersion unit (3), a stirring and suspension unit (4), a metering pump and control unit (5), a dosing pipeline (6), and a mixing unit (7); wherein: The evaporation unit (2) is configured to evaporate the stock liquid in the film-forming container (1) so that a residual film or residual layer is formed in the film-forming container (1); The ultrasonic dispersion unit (3) is configured to perform ultrasonic dispersion on the film-forming container (1) after the addition of the aqueous medium to obtain the dispersed mother liquor; The stirring and suspension unit (4) is configured to maintain the dispersion of the mother liquor during the addition process; The metering pump and control unit (5) is connected to the liquid outlet of the film-forming container (1) and is connected to the target aqueous phase system (8) through the dosing pipeline (6); The mixing unit (7) is disposed within the target aqueous system (8) or on a circulation loop connected to the target aqueous system (8) for mechanical stirring or circulating mixing of the target aqueous system (8).

10. The continuous and stable dosing device according to claim 9, characterized in that: The evaporation unit (2) includes at least one of an inert gas purging port, a ventilation port, a pressure reducing port, or a heating base; The ultrasonic dispersion unit (3) is an ultrasonic water bath or a probe ultrasonic device, and the film-forming container (1) is a solvent-resistant glass bottle or a polytetrafluoroethylene-lined container. The stirring and suspension unit (4) is a magnetic stirrer or a top stirrer, and is equipped with an anti-volatile sealing cover and / or an anti-contamination filter membrane; The metering pump and control unit (5) are linked with the target aqueous system (8) in operation cycle control to trigger the addition periodically or adjust the addition amount according to the feedback signal; The end of the dosing pipeline (6) is equipped with a check valve, distributor or multi-way switching valve (9) to achieve single reactor dosing or simultaneous / sequential dosing of multiple reactors.

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