A method for extracting PFAS from disposable plastic tableware

Abstract

The present invention belongs to the technical field of PFAS extraction and detection. The present invention provides a method for extracting PFAS from disposable plastic tableware, comprising extracting PFAS from a target mixed liquid by an ultrasonic extractor, obtaining ultrasonic extraction data, obtaining an extraction sufficiency value based on the ultrasonic extraction data, and comparing the value with a threshold value to generate a signal indicating whether the ultrasonic extraction is sufficient; then obtaining ultrasonic data of the PFAS extraction process in the target mixed liquid to obtain an ultrasonic fluctuation value, and comparing the value with a threshold value to generate an ultrasonic fluctuation size signal; when a large ultrasonic fluctuation signal is generated, obtaining the ultrasonic fluctuation value, calculating and processing to obtain an ultrasonic adjustment coefficient, and completing the adjustment of the ultrasonic extraction time of PFAS, thereby timely optimizing and adjusting the situation in which the ultrasonic fluctuation degree is large during the extraction process of PFAS from the disposable plastic tableware, thereby solving the problem of insufficient extraction of PFAS by the ultrasonic extractor.

Description

Technical Field

[0001] The present invention belongs to the technical field of PFAS extraction and detection, and specifically relates to a method for extracting PFAS from disposable plastic tableware. Background Art

[0002] PFAS (per- and polyfluoroalkyl substances) are a class of artificially synthesized organic compounds with high stability and bioaccumulation. These compounds are widely present in various consumer products, including disposable plastic tableware. Therefore, they pose a potential threat to human health and the environment. It is necessary to extract PFAS from disposable plastic tableware. When ultrasonic extraction is used, it is necessary to detect whether it is fully extracted from the disposable plastic tableware. If not, it is necessary to further analyze the reasons for the insufficient ultrasonic extraction and solve the reasons for the insufficient extraction of PFAS during ultrasonic extraction.

[0003] In the prior art, disposable plastic tableware is usually placed in an accelerated solvent extraction tank for PFAS extraction. Compared with the extraction of PFAS in disposable plastic tableware by ultrasound, the extraction efficiency of placing disposable plastic tableware in an accelerated solvent extraction tank is lower. However, when ultrasound is used to extract PFAS in disposable plastic tableware, it is necessary to detect whether PFAS is fully extracted from the disposable plastic tableware. If the extraction is not sufficient, it is necessary to further analyze the reasons for the insufficient ultrasonic extraction and solve the problem of insufficient extraction of PFAS due to large ultrasonic fluctuations when using ultrasound to extract PFAS.

[0004] To this end, the present invention provides a method for extracting PFAS from disposable plastic tableware. Summary of the invention

[0005] In order to make up for the shortcomings of the prior art, the problem raised in the background technology that when using ultrasound to extract PFAS, large ultrasonic fluctuations lead to insufficient extraction of PFAS is solved.

[0006] The technical solution adopted by the present invention to solve the technical problem is: a method for extracting PFAS from disposable plastic tableware, comprising:

[0007] Step 1: Mark the mixed solution after uniform stirring and mixing with the organic solvent as the target mixed solution, and extract the PFAS in the target mixed solution through an ultrasonic extractor. During the extraction of PFAS, obtain ultrasonic extraction data, wherein the ultrasonic extraction data includes a cavitation effect value and a penetration depth value;

[0008] Step 2: Based on the cavitation effect value and the penetration depth value, the extraction sufficiency value is obtained and compared with the threshold value to generate a signal indicating whether the ultrasonic extraction is sufficient;

[0009] Wherein, whether the ultrasonic extraction is sufficient signal includes an ultrasonic extraction sufficient signal or an ultrasonic extraction insufficient signal;

[0010] Step 3: Based on the ultrasonic extraction insufficiency signal, obtain the ultrasonic data of the PFAS extraction process in the target mixed solution, obtain the ultrasonic fluctuation value, and compare it with the threshold value to generate an ultrasonic fluctuation size signal;

[0011] Wherein, the ultrasonic wave magnitude signal includes an ultrasonic wave large signal or an ultrasonic wave small signal;

[0012] Step 4: When a large ultrasonic fluctuation signal is generated, the ultrasonic fluctuation value is obtained, and the ultrasonic adjustment coefficient is calculated and processed to complete the adjustment of the ultrasonic extraction time of PFAS.

[0013] As a further solution of the present invention, the cavitation effect value is obtained by:

[0014] Divide the target mixed solution into a number of equal regions, mark them as analysis regions, and obtain the total number of analysis regions;

[0015] A high-speed camera is used to statically photograph the analysis area in the target mixed solution to obtain an image of the analysis area;

[0016] Based on the analysis area image, the number of bubbles in each analysis area image is obtained and marked as the target bubble number;

[0017] Add up all the target bubble numbers to get the total target bubble number;

[0018] Calculate the ratio of the total number of target bubbles to the total number of analysis areas to obtain the target bubble ratio;

[0019] A high-speed camera is used to dynamically shoot each analysis area in the target mixed solution to obtain a video of the analysis area;

[0020] Based on the analysis area video, the life span of the bubble in each analysis area video is obtained and marked as the target bubble life span value;

[0021] The target bubble life value is obtained as follows:

[0022] In the video cycle of the analysis area, the time length value between the time node when each target bubble starts to appear and the time node when it disappears is obtained, and marked as the existence time of the target bubble;

[0023] The existence time of all target bubbles is added up and averaged to obtain the bubble survival time, and the ratio is calculated with the time length value corresponding to the video cycle of the analysis area to obtain the bubble survival time ratio;

[0024] Add up all bubble survival time proportions and take the average to get the target bubble life value;

[0025] The cavitation effect value is obtained by calculating the ratio of the target bubble ratio value to the target bubble life value.

[0026] As a further solution of the present invention, the penetration depth value is obtained by:

[0027] Obtain the ultrasonic wavelength used by the ultrasonic extractor and substitute the ultrasonic wavelength into the formula: The penetration depth value SD is calculated, where: Expressed as the ultrasonic wavelength.

[0028] As a further solution of the present invention, the method for obtaining the sufficient extraction value is:

[0029] The cavitation effect value and the penetration depth value are added together to calculate the extraction sufficiency value.

[0030] As a further solution of the present invention, the extraction sufficiency value is compared with the extraction sufficiency threshold value, and the comparison process is as follows:

[0031] If the extraction sufficiency value is greater than or equal to the extraction sufficiency threshold, an ultrasonic extraction sufficiency signal is generated;

[0032] If the extraction sufficiency value is less than the extraction sufficiency threshold, an ultrasonic extraction insufficiency signal is generated.

[0033] As a further solution of the present invention, the ultrasonic wave value is obtained by:

[0034] All ultrasonic amplitude values ​​are added and averaged to calculate the ultrasonic fluctuation value.

[0035] As a further solution of the present invention, the ultrasonic fluctuation value is compared with the ultrasonic fluctuation threshold value, and the comparison process is as follows:

[0036] If the ultrasonic fluctuation value is greater than the ultrasonic fluctuation threshold, a large ultrasonic fluctuation signal is generated;

[0037] If the ultrasonic fluctuation value is less than or equal to the ultrasonic fluctuation threshold, a small ultrasonic fluctuation signal is generated.

[0038] As a further solution of the present invention, the ultrasonic amplitude value is obtained by:

[0039] In the video cycle of the analysis area, the video cycle of the analysis area is divided into a number of target video time periods according to equal time intervals, and the ultrasonic intensity value at the start time node of the target video time period is added and averaged to obtain the ultrasonic intensity value;

[0040] The standard deviation of all ultrasonic intensity values ​​within the video period of the analysis area is calculated, and the ratio is calculated with the standard ultrasonic amplitude value to obtain the ultrasonic amplitude change value;

[0041] The ultrasonic amplitude variation values ​​of the video cycles of all analysis areas are added together to obtain the ultrasonic amplitude variation value.

[0042] As a further solution of the present invention, the ultrasonic adjustment coefficient is obtained by:

[0043] In the video cycle of the analysis area, the ultrasonic intensity value is obtained, and the ultrasonic intensity value is compared with the ultrasonic intensity threshold. The comparison process is as follows:

[0044] If the ultrasonic intensity value is greater than or equal to the ultrasonic intensity threshold, an extraction sufficient intensity signal is generated;

[0045] If the ultrasonic intensity value is less than the ultrasonic intensity threshold, an insufficient extraction intensity signal is generated;

[0046] The total time of generating insufficient extraction intensity signal in the video period of the analysis area is obtained, and marked as insufficient extraction time;

[0047] The ultrasonic adjustment time coefficient K is obtained by calculating the ratio of the insufficient extraction time to the time length value corresponding to the video cycle of the analysis area.

[0048] As a further solution of the present invention, the process of adjusting the ultrasonic extraction time of PFAS is as follows:

[0049] By formula: Calculate the required adjustment of ultrasonic extraction time for PFAS , T represents the process setting time for PFAS extraction in disposable plastic tableware, and K represents the ultrasonic adjustment time coefficient.

[0050] The beneficial effects of the present invention are as follows:

[0051] The present invention marks a mixed liquid after uniform stirring and mixing with an organic solvent as a target mixed liquid, and extracts PFAS in the target mixed liquid through an ultrasonic extractor. In the process of extracting PFAS, ultrasonic extraction data is obtained, wherein the ultrasonic extraction data includes a cavitation effect value and a penetration depth value, and the cavitation effect value and the penetration depth value are added and summed to calculate an extraction sufficiency value, and the extraction sufficiency value is compared with an extraction sufficiency threshold value. If the extraction sufficiency value is greater than or equal to the extraction sufficiency threshold value, it means that the cavitation effect of the ultrasonic wave on the target mixed liquid is greater, and the penetration depth of the target mixed liquid is greater than that of the ultrasonic wave. The greater the effect, the higher the sufficient extraction efficiency of PFAS in the target mixed liquid, and the more ultrasonic extraction sufficient signal is generated. If the extraction sufficient value is less than the extraction sufficient threshold, it means that the cavitation effect of the ultrasonic wave on the target mixed liquid is small, and the effect on the penetration depth of the target mixed liquid is small. The lower the sufficient extraction efficiency of PFAS in the target mixed liquid, the more ultrasonic extraction insufficient signal is generated, so as to analyze whether the extraction of PFAS is sufficient when the target mixed liquid is placed in the ultrasonic extractor. If the extraction is insufficient, it is necessary to analyze the degree of ultrasonic fluctuation in the ultrasonic extractor, and then further analyze the cause of insufficient ultrasonic extraction.

[0052] When the ultrasonic extraction insufficient signal is generated, the ultrasonic data of the PFAS extraction process in the target mixed solution is obtained, wherein the ultrasonic data includes the ultrasonic amplitude value, and all the ultrasonic amplitude values ​​are added and averaged to obtain the ultrasonic fluctuation value, thereby reflecting the overall fluctuation degree of the intensity change of the ultrasonic wave in the process of extracting the PFAS of the target mixed solution. If the ultrasonic fluctuation value is large, it means that the intensity fluctuation degree is large during the process of extracting the PFAS of the target mixed solution, and the probability of the ultrasonic extraction insufficient signal is large. If the ultrasonic fluctuation value is small, it means that the intensity fluctuation degree is small during the process of extracting the PFAS of the target mixed solution, and the probability of the ultrasonic extraction insufficient signal is small. Then, it is analyzed that the reason for the insufficient ultrasonic extraction of PFAS is caused by the large overall fluctuation degree of the ultrasonic wave in the process of extracting the PFAS.

[0053] The present invention generates a large ultrasonic fluctuation signal, obtains the ultrasonic fluctuation value, calculates and processes to obtain the ultrasonic adjustment coefficient, and completes the adjustment of the ultrasonic extraction time of PFAS, thereby adjusting and optimizing the ultrasonic extraction time of PFAS in disposable plastic tableware, solving the problem of insufficient extraction when using ultrasound to extract PFAS. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The present invention will be further described below in conjunction with the accompanying drawings.

[0055] Figure 1 is a flowchart of the steps of Embodiment 1 of the present invention;

[0056] Figure 2 is a flowchart of the steps of Embodiment 2 of the present invention;

[0057] Figure 3 is a flowchart of the steps of Embodiment 3 of the present invention;

[0058] Figure 4 It is a step flow chart of embodiment 4 of the present invention. DETAILED DESCRIPTION

[0059] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods. Example 1

[0060] like Figure 1 As shown, a method for extracting PFAS from disposable plastic tableware according to an embodiment of the present invention comprises:

[0061] First, the plastic sample to be tested is pretreated, wherein the pretreatment process includes: crushing and grinding the plastic sample; secondly, uniformly stirring the crushed and ground plastic sample; mixing the uniformly stirred plastic sample with an organic solvent to obtain a mixed liquid, and extracting PFAS in the mixed liquid by ultrasonic extraction, wherein the organic solvent includes methanol and acetonitrile; then, purifying the extracted liquid, and using the purified extract to adsorb PFAS by solid phase extraction to complete the purification of PFAS. Example 2

[0062] like Figure 2 As shown, a method for extracting PFAS from disposable plastic tableware according to an embodiment of the present invention analyzes the process of extracting PFAS from a mixed liquid by ultrasonic extraction in Example 1, including:

[0063] Step 1: Mark the mixed solution after uniform stirring and mixing with the organic solvent as the target mixed solution, extract the PFAS in the target mixed solution, and obtain ultrasonic extraction data, wherein the ultrasonic extraction data includes the cavitation effect value and the penetration depth value;

[0064] In some embodiments, the mixed solution after uniform stirring and mixing with the organic solvent is marked as the target mixed solution, and the PFAS in the target mixed solution is extracted by an ultrasonic extractor to obtain ultrasonic extraction data, wherein the ultrasonic extraction data includes a cavitation effect value and a penetration depth value, and the specific process is as follows:

[0065] First, the specific process of obtaining the cavitation effect value is as follows:

[0066] Divide the target mixed solution into a number of equal regions, mark them as analysis regions, and obtain the total number of analysis regions;

[0067] The target mixed liquid is divided in the following manner: the target mixed liquid is divided into equal volumes in a vertical direction of the target mixed liquid;

[0068] A high-speed camera is used to statically photograph the analysis area in the target mixed solution to obtain an image of the analysis area;

[0069] Based on the analysis area image, the number of bubbles in each analysis area image is obtained and marked as the target bubble number;

[0070] Add up all the target bubble numbers to get the total target bubble number;

[0071] Calculate the ratio of the total number of target bubbles to the total number of analysis areas to obtain the target bubble ratio;

[0072] Using a high-speed camera to dynamically shoot each analysis area in the target mixed solution, obtain a video of the analysis area, and acquire a video cycle of the analysis area;

[0073] It should be noted that: the duration of the video cycle in each analysis area is consistent;

[0074] Based on the analysis area video, the life span of the bubble in each analysis area video is obtained and marked as the target bubble life span value;

[0075] The target bubble life value is obtained as follows:

[0076] In the video cycle of the analysis area, the time length value between the time node when each target bubble starts to appear and the time node when it disappears is obtained, and marked as the existence time of the target bubble;

[0077] The existence time of all target bubbles is added up and averaged to obtain the bubble survival time, and the ratio is calculated with the time length value corresponding to the video cycle of the analysis area to obtain the bubble survival time ratio;

[0078] Add up all bubble survival time proportions and take the average to get the target bubble life value;

[0079] The target bubble ratio value is calculated by ratio calculation with the target bubble life value to obtain the cavitation effect value;

[0080] It can be understood that: the meaning of the cavitation effect value is: a comprehensive measure of the number of target bubbles and the target bubble life span generated by ultrasound in the target mixed liquid, reflecting the physical effect intensity of ultrasound on the target mixed liquid. If the target bubble ratio value is larger and the target bubble life span value is smaller, it means that the physical effect intensity of ultrasound on the target mixed liquid is stronger, and the full extraction efficiency of PFAS in the target mixed liquid is higher; if the target bubble ratio value is smaller and the target bubble life span value is larger, it means that the physical effect intensity of ultrasound on the target mixed liquid is weaker, and the full extraction efficiency of PFAS in the target mixed liquid is lower.

[0081] The second specific method for obtaining the penetration depth value is:

[0082] Obtain the ultrasonic wavelength used by the ultrasonic extractor and substitute the ultrasonic wavelength into the formula: The penetration depth value SD is calculated, where: Expressed as the ultrasonic wavelength;

[0083] It can be understood that the penetration depth value means the depth to which ultrasound can effectively propagate in the target mixed solution, which determines the ability of ultrasound to extract PFAS in the target mixed solution. If the wavelength of ultrasound is larger, it means that the penetration depth of ultrasound in the target mixed solution is larger, and the efficiency of fully extracting PFAS in the target mixed solution is higher; if the wavelength of ultrasound is smaller, it means that the penetration depth of ultrasound in the target mixed solution is smaller, and the efficiency of fully extracting PFAS in the target mixed solution is lower.

[0084] Step 2: Based on the cavitation effect value and the penetration depth value, the extraction sufficiency value is obtained and compared with the threshold value to generate a signal indicating whether the ultrasonic extraction is sufficient;

[0085] Wherein, whether the ultrasonic extraction is sufficient signal includes an ultrasonic extraction sufficient signal or an ultrasonic extraction insufficient signal;

[0086] In some embodiments, based on the cavitation effect value and the penetration depth value, the cavitation effect value and the penetration depth value are added and summed to calculate an extraction sufficiency value, and the extraction sufficiency value is compared with the extraction sufficiency threshold value, and the comparison process is as follows:

[0087] If the extraction sufficiency value is greater than or equal to the extraction sufficiency threshold, it means that the cavitation effect of the ultrasonic wave on the target mixed liquid is greater, and the penetration depth effect on the target mixed liquid is greater. Therefore, the PFAS sufficiency extraction efficiency in the target mixed liquid is higher, and an ultrasonic extraction sufficiency signal is generated;

[0088] If the extraction sufficiency value is less than the extraction sufficiency threshold, it means that the cavitation effect of the ultrasound on the target mixed solution is smaller, and the penetration depth effect on the target mixed solution is smaller. Therefore, the PFAS sufficiency extraction efficiency in the target mixed solution is lower, and an ultrasonic extraction insufficiency signal is generated;

[0089] Among them, it is necessary to further explain that: the meaning of the extraction sufficiency value is: a combination of two key factors: the physical effect intensity (i.e., cavitation effect) generated by ultrasound in the target mixed liquid and the depth to which ultrasound can effectively propagate (i.e., penetration depth), and the size of the extraction sufficiency value directly reflects the ability of ultrasound to extract PFAS in the target mixed liquid. When the extraction sufficiency value is high, it means that the cavitation effect generated by ultrasound in the target mixed liquid is stronger, and the penetration depth of the target mixed liquid is greater, thereby improving the extraction efficiency of PFAS in the target mixed liquid; on the contrary, when the extraction sufficiency value is low, it means that the cavitation effect generated by ultrasound in the target mixed liquid is weaker, and the penetration depth of the target mixed liquid is smaller, resulting in a lower extraction efficiency of PFAS in the target mixed liquid;

[0090] Specific implementation scheme of the embodiment of the present invention: the mixed liquid after uniform stirring and mixing with the organic solvent is marked as the target mixed liquid, and the PFAS in the target mixed liquid is extracted by an ultrasonic extractor. In the process of extracting PFAS, ultrasonic extraction data is obtained, wherein the ultrasonic extraction data includes a cavitation effect value and a penetration depth value, and the cavitation effect value and the penetration depth value are added and summed to calculate the extraction sufficiency value, and the extraction sufficiency value is compared with the extraction sufficiency threshold value. If the extraction sufficiency value is greater than or equal to the extraction sufficiency threshold value, it means that the cavitation effect of the ultrasonic wave on the target mixed liquid is large, and the target mixed liquid is The greater the effect of penetration depth, the higher the efficiency of sufficient extraction of PFAS in the target mixed liquid, and the more a sufficient ultrasonic extraction signal is generated. If the sufficient extraction value is less than the sufficient extraction threshold, it means that the cavitation effect of the ultrasonic wave on the target mixed liquid is small, and the effect of penetration depth on the target mixed liquid is small, and the less the efficiency of sufficient extraction of PFAS in the target mixed liquid is, the more an insufficient ultrasonic extraction signal is generated, thereby analyzing whether the extraction of PFAS is sufficient when the target mixed liquid is placed in the ultrasonic extractor. If the extraction is insufficient, it is necessary to analyze the degree of ultrasonic fluctuation in the ultrasonic extractor, and then further analyze the cause of insufficient ultrasonic extraction. Example 3

[0091] like Figure 3 As shown, a method for extracting PFAS from disposable plastic tableware according to an embodiment of the present invention comprises:

[0092] Step 3: Based on the ultrasonic extraction insufficiency signal, obtain the ultrasonic data of the PFAS extraction process in the target mixed solution, obtain the ultrasonic fluctuation value, and compare it with the threshold value to generate an ultrasonic fluctuation size signal;

[0093] Wherein, the ultrasonic wave magnitude signal includes an ultrasonic wave large signal or an ultrasonic wave small signal;

[0094] In some embodiments, when an ultrasonic extraction insufficiency signal is generated, ultrasonic data of the PFAS extraction process in the target mixed solution is obtained, wherein the ultrasonic data includes ultrasonic amplitude values, and all ultrasonic amplitude values ​​are added and averaged to calculate the ultrasonic fluctuation value;

[0095] The ultrasonic fluctuation value is compared with the ultrasonic fluctuation threshold. The comparison process is as follows:

[0096] If the ultrasonic fluctuation value is greater than the ultrasonic fluctuation threshold, it means that the ultrasonic fluctuation degree is large during the extraction of PFAS from the target mixed solution, and the probability of an insufficient ultrasonic extraction signal is high, generating a large ultrasonic fluctuation signal;

[0097] If the ultrasonic fluctuation value is less than or equal to the ultrasonic fluctuation threshold, it means that the ultrasonic fluctuation degree is small during the process of ultrasonic extraction of PFAS in the target mixed solution, the probability of ultrasonic extraction insufficiency signal is small, and a small ultrasonic fluctuation signal is generated;

[0098] It needs to be further explained that: the meaning of the ultrasonic fluctuation value is: in the process of extracting PFAS from the target mixed liquid, it is a comprehensive index obtained by adding and averaging the ultrasonic amplitude values ​​in the video cycle of each analysis area, which reflects the overall fluctuation degree of the ultrasonic intensity change in the process of extracting PFAS from the target mixed liquid. If the ultrasonic fluctuation value is large, it means that the ultrasonic fluctuation degree is large in the process of extracting PFAS from the target mixed liquid, and the probability of the ultrasonic extraction insufficiency signal is large. If the ultrasonic fluctuation value is small, it means that the ultrasonic fluctuation degree is small in the process of extracting PFAS from the target mixed liquid, and the probability of the ultrasonic extraction insufficiency signal is small.

[0099] Exemplarily, the ultrasonic amplitude value is obtained in the following manner:

[0100] In the video cycle of the analysis area, the video cycle of the analysis area is divided into a number of target video time periods according to equal time intervals, and the ultrasonic intensity value at the start time node of the target video time period is added and averaged to obtain the ultrasonic intensity value;

[0101] The standard deviation of all ultrasonic intensity values ​​within the video period of the analysis area is calculated, and the ratio is calculated with the standard ultrasonic amplitude value to obtain the ultrasonic amplitude change value;

[0102] The ultrasonic amplitude variation values ​​of the video cycles of all analysis areas are added up to obtain the ultrasonic amplitude variation value;

[0103] It can be understood that the ultrasonic amplitude value means the overall fluctuation degree of the ultrasonic intensity change within the video cycle of the analysis area, which reflects the intensity of the ultrasonic wave when it propagates in each analysis area in the target mixed liquid, and the stability and consistency of its intensity change over time. If the ultrasonic amplitude value is large, it means that the ultrasonic intensity fluctuates greatly during the ultrasonic extraction of the target mixed liquid. If the ultrasonic amplitude value is small, it means that the ultrasonic intensity change is relatively stable during the ultrasonic extraction of the target mixed liquid, which is conducive to maintaining a high extraction efficiency.

[0104] The specific implementation scheme of the embodiment of the present invention is: when an ultrasonic extraction insufficiency signal is generated, ultrasonic data of the PFAS extraction process in the target mixed liquid is obtained, wherein the ultrasonic data includes ultrasonic amplitude values, all ultrasonic amplitude values ​​are added and averaged, and the ultrasonic fluctuation value is calculated, thereby reflecting the overall fluctuation degree of the intensity change of the ultrasonic wave in the process of extracting PFAS from the target mixed liquid. If the ultrasonic fluctuation value is large, it means that the intensity fluctuation degree is large during the process of extracting PFAS from the target mixed liquid, and the probability of the ultrasonic extraction insufficiency signal is large. If the ultrasonic fluctuation value is small, it means that the intensity fluctuation degree is small during the process of extracting PFAS from the target mixed liquid, and the probability of the ultrasonic extraction insufficiency signal is small. Then, it is analyzed that the reason for the insufficient ultrasonic extraction of PFAS is caused by the large overall fluctuation degree of the ultrasonic wave in the process of extracting PFAS. Example 4

[0105] like Figure 4 As shown, a method for extracting PFAS from disposable plastic tableware according to an embodiment of the present invention comprises:

[0106] Step 4: Based on the large ultrasonic wave signal, the current ultrasonic extraction time value is obtained, and the ultrasonic adjustment coefficient is calculated and processed to complete the adjustment of the ultrasonic extraction time of PFAS;

[0107] In some embodiments, when a large ultrasonic wave fluctuation signal is generated, the ultrasonic wave fluctuation value is obtained, and the ultrasonic adjustment coefficient is calculated to complete the adjustment of the ultrasonic extraction time of PFAS;

[0108] Among them, the ultrasonic adjustment coefficient is obtained as follows:

[0109] In the video cycle of the analysis area, the ultrasonic intensity value is obtained, and the ultrasonic intensity value is compared with the ultrasonic intensity threshold. The comparison process is as follows:

[0110] If the ultrasonic intensity value is greater than or equal to the ultrasonic intensity threshold, it means that the ultrasonic intensity is conducive to the full extraction of PFAS in the target mixed solution (the ultrasonic intensity only needs to reach the intensity that can fully extract PFAS in the target mixed solution), and a sufficient extraction intensity signal is generated;

[0111] If the ultrasonic intensity value is less than the ultrasonic intensity threshold, it means that the ultrasonic intensity is not conducive to the sufficient extraction of PFAS in the target mixed solution, and an insufficient extraction intensity signal is generated;

[0112] The total time of generating insufficient extraction intensity signal in the video period of the analysis area is obtained, and marked as insufficient extraction time;

[0113] The ratio of the insufficient extraction time to the time length corresponding to the video cycle of the analysis area is calculated to obtain the ultrasonic adjustment time coefficient K;

[0114] Exemplarily, the process of adjusting the ultrasonic extraction time of PFAS is as follows:

[0115] By formula: , calculate the required adjustment of ultrasonic extraction time of PFAS , T represents the process setting time for PFAS extraction from disposable plastic tableware, and K represents the ultrasonic adjustment time coefficient;

[0116] The specific implementation plan of the embodiment of the present invention is: when a large ultrasonic fluctuation signal is generated, the ultrasonic fluctuation value is obtained, and the ultrasonic adjustment coefficient is calculated and processed to complete the adjustment of the ultrasonic extraction time of PFAS, thereby adjusting and optimizing the ultrasonic extraction time of PFAS in disposable plastic tableware, solving the problem of insufficient extraction when using ultrasound to extract PFAS.

[0117] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for extracting PFAS from disposable plastic tableware, characterized in that: include: Step 1: Mark the mixed solution after uniform stirring and mixing with the organic solvent as the target mixed solution, and extract the PFAS in the target mixed solution through an ultrasonic extractor. During the extraction of PFAS, obtain ultrasonic extraction data, wherein the ultrasonic extraction data includes a cavitation effect value and a penetration depth value; The cavitation effect value is obtained as follows: Divide the target mixed solution into a number of equal regions, mark them as analysis regions, and obtain the total number of analysis regions; A high-speed camera is used to statically photograph the analysis area in the target mixed solution to obtain an image of the analysis area; Based on the analysis area image, the number of bubbles in each analysis area image is obtained and marked as the target bubble number; Add up all the target bubble numbers to get the total target bubble number; Calculate the ratio of the total number of target bubbles to the total number of analysis areas to obtain the target bubble ratio; A high-speed camera is used to dynamically shoot each analysis area in the target mixed solution to obtain a video of the analysis area; Based on the analysis area video, the life span of the bubble in each analysis area video is obtained and marked as the target bubble life span value; The target bubble life value is obtained as follows: In the video cycle of the analysis area, the time length value between the time node when each target bubble starts to appear and the time node when it disappears is obtained, and marked as the existence time of the target bubble; The existence time of all target bubbles is added up and averaged to obtain the bubble survival time, and the ratio is calculated with the time length value corresponding to the video cycle of the analysis area to obtain the bubble survival time ratio; Add up all bubble survival time proportions and take the average to get the target bubble life value; The target bubble ratio value is calculated by ratio calculation with the target bubble life value to obtain the cavitation effect value; The penetration depth value is obtained as follows: Obtain the ultrasonic wavelength used by the ultrasonic extractor and substitute the ultrasonic wavelength into the formula: The penetration depth value SD is calculated, where: Expressed as the ultrasonic wavelength; Step 2: Based on the cavitation effect value and the penetration depth value, the extraction sufficiency value is obtained and compared with the threshold value to generate a signal indicating whether the ultrasonic extraction is sufficient; Wherein, whether the ultrasonic extraction is sufficient signal includes an ultrasonic extraction sufficient signal or an ultrasonic extraction insufficient signal; The method for obtaining the extraction sufficient value is: The cavitation effect value and the penetration depth value are added together to calculate the extraction sufficiency value; Step 3: Based on the ultrasonic extraction insufficiency signal, obtain the ultrasonic data of the PFAS extraction process in the target mixed solution, obtain the ultrasonic fluctuation value, and compare it with the threshold value to generate an ultrasonic fluctuation size signal; Wherein, the ultrasonic wave magnitude signal includes an ultrasonic wave large signal or an ultrasonic wave small signal; The ultrasonic wave value is obtained as follows: All ultrasonic amplitude values ​​are added and averaged to calculate the ultrasonic fluctuation value; The ultrasonic amplitude value is obtained as follows: In the video cycle of the analysis area, the video cycle of the analysis area is divided into a number of target video time periods according to equal time intervals, and the ultrasonic intensity value at the start time node of the target video time period is added and averaged to obtain the ultrasonic intensity value; The standard deviation of all ultrasonic intensity values ​​within the video period of the analysis area is calculated, and the ratio is calculated with the standard ultrasonic amplitude value to obtain the ultrasonic amplitude change value; The ultrasonic amplitude variation values ​​of the video cycles of all analysis areas are added up to obtain the ultrasonic amplitude variation value; Step 4: When a large ultrasonic fluctuation signal is generated, the ultrasonic fluctuation value is obtained, and the ultrasonic adjustment coefficient is calculated and processed to complete the adjustment of the ultrasonic extraction time of PFAS; The ultrasonic adjustment coefficient is obtained as follows: In the video cycle of the analysis area, the ultrasonic intensity value is obtained, and the ultrasonic intensity value is compared with the ultrasonic intensity threshold. The comparison process is as follows: If the ultrasonic intensity value is greater than or equal to the ultrasonic intensity threshold, an extraction sufficient intensity signal is generated; If the ultrasonic intensity value is less than the ultrasonic intensity threshold, an insufficient extraction intensity signal is generated; The total time of generating insufficient extraction intensity signal in the video period of the analysis area is obtained, and marked as insufficient extraction time; The ratio of the insufficient extraction time to the time length corresponding to the video cycle of the analysis area is calculated to obtain the ultrasonic adjustment time coefficient K; The adjustment process of ultrasonic extraction time of PFAS is as follows: By formula: , calculate the required adjustment of ultrasonic extraction time of PFAS , T represents the process setting time for PFAS extraction in disposable plastic tableware, and K represents the ultrasonic adjustment time coefficient.

2. The method for extracting PFAS from disposable plastic tableware according to claim 1, characterized in that: The extraction sufficiency value is compared with the extraction sufficiency threshold, and the comparison process is as follows: If the extraction sufficiency value is greater than or equal to the extraction sufficiency threshold, an ultrasonic extraction sufficiency signal is generated; If the extraction sufficiency value is less than the extraction sufficiency threshold, an ultrasonic extraction insufficiency signal is generated.

3. The method for extracting PFAS from disposable plastic tableware according to claim 1, characterized in that: The ultrasonic fluctuation value is compared with the ultrasonic fluctuation threshold. The comparison process is as follows: If the ultrasonic fluctuation value is greater than the ultrasonic fluctuation threshold, a large ultrasonic fluctuation signal is generated; If the ultrasonic fluctuation value is less than or equal to the ultrasonic fluctuation threshold, a small ultrasonic fluctuation signal is generated.

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