Method for determining heavy metal content of solid waste powder

Abstract

The invention discloses a solid waste powder heavy metal content determination method, and relates to the technical field of heavy metal content analysis, and the method comprises the following steps: S1, solid waste powder is pretreated, and a chemical reagent is added into a mother liquor preparation reaction tank for heavy metal element leaching; adding a specific element color developing reagent to obtain a specific metal complex of each heavy metal element subjected to fluorescence labeling; s2, carrying out electrophoretic separation on the heavy metal complex by adopting an electrophoresis cell fluorescence detection compound system, and carrying out fluorescence detection to obtain test index data; and S3, according to the test index data, carrying out a specific evaluation method to divide danger levels, and guiding subsequent solid waste powder treatment. The method can quantitatively evaluate the heavy metal content of the solid waste powder and perform visual treatment, and provides related scientific basis and technical support for improving the rapid decision-making efficiency and treatment rationality of the solid waste powder material in the construction site.

Description

Technical Field

[0001] The invention relates to the technical field of heavy metal content analysis, in particular to a method for determining the heavy metal content of solid waste powder. Background Art

[0002] With the acceleration of industrialization and urbanization, the amount of solid waste generated continues to grow, and the heavy metal components contained in it pose a significant threat to environmental quality and human health. Specifically, heavy metal elements such as lead, cadmium, copper, and chromium have attracted much attention due to their high toxicity, persistence, and bioaccumulation. Once these heavy metals enter the soil, water, or atmospheric environment, they will be difficult to degrade naturally and may exist for a long time, leading to an imbalance in the ecosystem and potential risks to human health. Based on this, accurately determining the heavy metal content in solid waste and formulating effective disposal strategies have become important issues in the field of environmental protection and resource recovery.

[0003] Nowadays, the determination of heavy metal content in solid waste mainly relies on laboratory analysis methods, such as atomic absorption spectroscopy (AAS), inductively coupled plasma mass spectrometry (ICP-MS), etc. However, the existing evaluation methods still have certain problems or defects. First, the time cost of the existing determination methods is too high, and the samples need to be collected and sent to the laboratory for processing and analysis, which cannot meet the needs of rapid decision-making at the construction site; secondly, the laboratory equipment relied on by the existing test methods is expensive and complicated to operate, requiring professional technicians to operate, which increases the manpower and technical thresholds and is difficult to promote in a wide range of practical applications; thirdly, the existing traditional test methods for the heavy metal content of solid waste powder can usually only provide numerical data, which is difficult to intuitively display the distribution of heavy metals, which brings difficulties to the understanding and application of non-professionals, and also cannot meet the needs of rapid decision-making at the construction site. Therefore, it is still urgent to propose a reasonable and effective method for visual classification of solid waste and determination of engineering application methods, so as to provide relevant scientific basis and technical support for improving the efficiency and rationality of the treatment decision-making of solid waste powder materials at the construction site. Summary of the invention

[0004] In view of the problems existing in the existing methods for determining engineering applications of heavy metals in solid waste, the present invention is proposed.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: A method for determining the heavy metal content of solid waste powder comprises the following steps: S1. Pre-treating solid waste powder, adding chemical reagents to a mother liquor preparation reaction tank to leach heavy metal elements; adding specific element color developing reagents to obtain specific metal complexes of each heavy metal element after fluorescent labeling; S2. Use an electrophoresis pool fluorescence detection composite system to perform electrophoretic separation on the heavy metal complexes and perform fluorescence detection to obtain test index data; S3. Classify the hazard level using a specific evaluation method based on the test index data to guide the subsequent disposal of solid waste powder; As a preferred technical solution of the present invention, in step S1, the electrophoresis pool fluorescence detection composite system includes an electrophoresis device, a fluorescence detection system arranged at the bottom of the electrophoresis pool, and a numerical control unit arranged below the fluorescence detection system; The front side wall of the outer wall of the electrophoresis device is provided with a buffer addition outlet, and the right side wall thereof is provided with an electrophoresis sample pool replacement station. The electrophoresis device comprises an electrophoresis sample pool, and positive and negative electrophoresis sample pool electrodes are provided at both ends of the sample pool. Lead wires from the electrophoresis sample pool electrodes are connected to the power supply of the electrophoresis device; The fluorescence detection system comprises a fluorescence marker excitation layer and a high-precision fluorescence detection system; the fluorescence marker excitation layer is arranged at the bottom of the electrophoresis sample pool, and the electrophoresis sample pool and the fluorescence marker excitation layer are separated by a high-transmittance impermeable layer; the fluorescence marker excitation layer is connected and arranged above the high-precision fluorescence detection system, and the high-precision fluorescence detection system comprises a plurality of high-precision fluorescence detection cameras; The numerical control unit is arranged below the power supply of the fluorescence detection system and the electrophoresis device, and the numerical control unit and the fluorescence detection system are connected via a data transmission conduit; As a preferred technical solution of the present invention, in step S1, the method for pre-treating the solid waste powder includes: sampling the solid waste powder by the quartering method; putting a batch of solid waste powder into a vibrating screen machine for vibrating and mixing evenly, spreading the mixed solid waste powder into a square thin layer with uniform thickness, dividing it into four equal parts by a cross cutting method, and taking two parts on the diagonal line for further mixing; repeating this process until the sample weight is 500-600g; The solid waste powder is ground, the sample is added into a ball mill, alumina ceramic balls are selected as grinding media, the grinding ball size is selected to be 1-5 mm, the ball-to-material ratio is set to 10:1, the rotation speed is set to 300-500 rpm / min, and the grinding time is set to 30-40 min; The ground solid waste powder sample is subjected to heavy metal element leaching, and a 3-5 mol / L hydrochloric acid solution is selected as the leaching reagent, and the leaching time is set to 24 h. After reaching the predetermined leaching time, a 0.45 μm microporous filter membrane is used to filter the leaching solution to obtain a high leaching amount of heavy metals in the solid waste powder; The heavy metals in the solid waste powder are subjected to color development treatment, and a fluorescently labeled heavy metal complex ligand is added to the high leaching amount solution of the heavy metals in the solid waste powder. The reagents used are specifically: 5mmol / L 1,10-phenanthroline reagent was used for specific complex labeling of Cu, with an excitation wavelength of 370nm and an emission wavelength of 520nm; 1 μmol / L LeadmiumGreen reagent was used to specifically complex and label Pb, with an excitation wavelength of 490 nm and an emission wavelength of 520 nm; Cadmium-specific fluorophore at 5 μmol / L was used to specifically complex Cd, with an excitation wavelength of 488 nm and an emission wavelength of 520 nm; 1mmol / L AlizarinRedS was used to specifically complex Cr, with an excitation wavelength of 430nm and an emission wavelength of 560nm; The ligand reagents used are mixed and added to the high leaching amount solution of heavy metals in solid waste powder, and incubated for 40-60 minutes to ensure that the heavy metal elements are completely complexed; after the complex incubation is completed, the obtained sample solution is subjected to SPE solid phase extraction operation to separate the excess ligand and heavy metal complex; The specific technical parameters for the implementation of solid phase extraction are: cation exchange resin is selected as the adsorbent, methanol is selected as the activation pretreatment reagent, and 2% HCl solution is used as the elution solvent; the sample loading flow rate during solid phase extraction is limited to 1-2 ml / min; the eluate is collected and subsequently heated and concentrated to obtain the solid waste powder heavy metal electrophoresis sample solution; As a preferred technical solution of the present invention, in step S2, the electrophoretic separation of heavy metal complexes using an electrophoretic cell fluorescence detection composite system is specifically as follows: The collected solid waste powder heavy metal electrophoresis sample solution is added to the electrophoresis pool of the composite system for gel electrophoresis, and the gel is selected as 15% polyacrylamide gel; the buffer is selected as phosphate buffer PBS; HCl with a mass fraction of 0.1% is used to adjust the pH value, and the pH value of the electrophoresis sample pool is adjusted to 5.5-6.0; the electrophoresis voltage is set to 100-120V; the electrophoresis time is set to 30-60min; the electrophoresis pool comprises two lanes, the solid waste powder heavy metal electrophoresis sample solution is injected into the first lane, and the same amount of heavy metal standard content solution is injected into the second lane. This solution is the maximum heavy metal content standard solution allowed by the environment in the specification, and is a precisely known concentration solution prepared by titration. The heavy metal standard content solution contains four heavy metal elements of Cu, Pb, Cd, and Cr, and is treated with the same fluorescent ligand complexation labeling as the solid waste powder heavy metal electrophoresis sample solution, and electrophoresis separation is started; In step S2, the test index data is obtained by turning off the power supply after the preset electrophoresis time is reached, turning on the fluorescent imaging device of the composite system to detect the specific complex of the metal, and obtaining the length L of each band in the electrophoresis spectrum. ij ; After background correction to remove non-specific fluorescence signals, record the fluorescence signal intensity Q of each band ij , where i is the lane number, i=1,2; j is the color band number, j=1,2,3,4; the test index data is imported into the ImageJ image analysis software, and the fluorescence intensity distribution diagram of the heavy metal leaching data of the first lane and the fluorescence intensity distribution diagram of the heavy metal standard data of the second lane are respectively drawn with the length as the horizontal axis and the fluorescence intensity as the vertical axis; As a preferred technical solution of the present invention, in step S3, the hazard level is divided according to the test index data by a specific evaluation method, specifically: using image processing software to integrate the fluorescence intensity distribution diagram of the heavy metal standard data, and the result is defined as the heavy metal standard data m 标准j , where the integral limit is the length L of each strip 2j , different bands corresponding to different elements are integrated respectively; similarly, the fluorescence intensity distribution diagram of heavy metal leaching data is integrated, and the result is defined as the heavy metal leaching data m 1j , where j is the number of the color band, j=1,2,3,4; Definition of heavy metal leaching data difference M j , and its calculation formula is as follows: ; Where: M j is the difference of heavy metal leaching data; m 1j is the heavy metal leaching data of the jth band in the first lane; m 标准j is the heavy metal standard data of the jth band in the second lane; where j=1,2,3,4; Definition of heavy metal environmental concentration difference C j , C j With M j The satisfying relationship is as follows: Table 1 Conversion table of heavy metal environmental concentration differences The characteristic of the classification of danger levels is to calculate the comprehensive evaluation index hazard index HI, and its calculation formula is as follows: ; Where: HI is the hazard index; C j is the heavy metal environmental difference; R j is the hazard level coefficient of the jth element, R jIn order to set the danger level of each heavy metal element according to the content requirements of various elements in the "Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard" GB15618-2018 and the "Drinking Water Hygiene Standard" GB5749-2022, the specific values ​​are shown in Table 2, where j=1,2,3,4; Table 2 Hazard level reference table of each heavy metal element The subsequent treatment of solid waste powder is guided by the hazard index HI, specifically: (1) HI<100: suitable for resource utilization; (2) 100≤HI<300: more suitable, but needs to be evaluated carefully; (3) 300≤HI<400: not suitable, treatment plan needs to be improved; (4) HI ≥ 400: Not suitable for resource utilization and requires safe treatment.

[0006] Compared with the prior art, the present invention has the following beneficial effects: more accurate and scientific quantitative evaluation and analysis can be performed by visualizing the classification of heavy metal content in solid waste powder at the powdery particle scale; and the method can simultaneously determine a variety of different heavy metal elements in solid waste powder, and visualize the heavy metal content to simplify the analysis results; at the same time, new evaluation indicators are introduced on the basis of traditional evaluation methods, and various influencing factors are taken into account, providing relevant scientific basis and technical support for improving the efficiency of rapid decision-making and rationality of treatment of solid waste powdery materials at construction sites. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them: Figure 1 Flow chart of the method for determining the heavy metal content of solid waste powder.

[0008] Figure 2 This is the overall diagram of the visual grading test equipment for heavy metal content in solid waste powder.

[0009] Figure 3 This is a cross-sectional diagram of a visual grading test device for heavy metal content in solid waste powder.

[0010] Figure 4 This is the fluorescence intensity distribution diagram of heavy metal leaching data.

[0011] Figure 5 This is the fluorescence intensity distribution diagram of heavy metal standard data.

[0012] In the figure: 1. Electrophoresis equipment; 2. Fluorescence detection system; 3. Electrophoresis sample cell; 4. Electrophoresis sample cell electrode; 5. Electrophoresis device power supply; 6. Fluorescence marker excitation layer; 7. High-precision fluorescence detection system; 8. High-transmittance impermeable layer; 9. High-precision fluorescence detection camera; 10. Data transmission catheter; 11. Electrophoresis sample cell replacement point; 12. Buffer addition discharge port; 13. CNC unit. DETAILED DESCRIPTION

[0013] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0014] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0015] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0016] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0017] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0018] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] A method for determining the heavy metal content of solid waste powder. The powder sample is derived from fly ash incinerated by a grate furnace in a waste incineration plant in Zhongshan. The main incineration material is municipal solid waste. The particle size range is 4-45 μm and the density range is 1.0-3.0 g / cm 3 .

[0020] Reference Figure 1~Figure 5 , which is the first embodiment of the present invention, provides a method for determining the heavy metal content of solid waste powder, comprising the following steps: S1. Use the quartering method to sample solid waste powder; put a batch of solid waste powder into a vibrating screen to vibrate and mix evenly, spread the mixed solid waste powder into a square thin layer of uniform thickness, divide it into four equal parts using a cross cutting method, take two parts on the diagonal and continue mixing; repeat this process until the sample weight is 600g.

[0021] The solid waste powder was ground and added into a ball mill. Alumina ceramic balls were selected as grinding media. The grinding ball size was 5 mm, the ball-to-material ratio was set to 10:1, the rotation speed was set to 400 rpm / min, and the grinding time was set to 40 min.

[0022] The heavy metal elements were leached from the ground solid waste powder samples. The leaching reagent was 3-5 mol / L hydrochloric acid solution. The leaching time was set to 24 h. After the predetermined leaching time was reached, the leaching solution was filtered with a 0.45 μm microporous filter membrane to obtain a high leaching amount of heavy metals in the solid waste powder solution.

[0023] The heavy metals in the solid waste powder are subjected to color development treatment, and a fluorescently labeled heavy metal complex ligand is added to the high leaching amount solution of the heavy metals in the solid waste powder. The reagents used are specifically: Cu was specifically labeled with 1,10-phenanthroline reagent at 5mmol / L; Pb was specifically labeled with Leadmium Green reagent at 1μmol / L; Cd was specifically labeled with Cadmium-specificfluorophore at 5μmol / L; and Cr was specifically labeled with Alizarin Red S at 1mmol / L.

[0024] The ligand reagents used are mixed and added to the high leaching amount solution of heavy metals in solid waste powder, and incubated for 60 minutes to ensure that the heavy metal elements are completely complexed; after the complex incubation is completed, the sample solution obtained is subjected to SPE solid phase extraction operation to separate the excess ligand and heavy metal complex; The specific technical parameters for the implementation of solid phase extraction are as follows: cation exchange resin is selected as the adsorbent, methanol is selected as the activation pretreatment reagent, and 2% HCl solution is used as the elution solvent; the sample loading flow rate during solid phase extraction is limited to 1 ml / min; the eluent is collected and subsequently heated and concentrated to finally obtain 10 ml of solid waste powder heavy metal electrophoresis sample solution.

[0025] S2. Electrophoresis separation of heavy metal complexes using an electrophoresis pool fluorescence detection composite system is as follows: the collected solid waste powder heavy metal electrophoresis sample solution is added to the electrophoresis pool of the composite system for gel electrophoresis, and 15% polyacrylamide gel is selected as the gel; the buffer solution is selected as phosphate buffer PBS; 0.1% HCl is used to adjust the pH value, and the pH value of the electrophoresis sample pool is adjusted to the range of [5.5, 6.0]; the electrophoresis voltage is set to 120V; the electrophoresis time is set to 40min; the electrophoresis pool contains two lanes, 10ml of solid waste powder heavy metal electrophoresis sample solution is injected into the first lane, and 10ml of heavy metal standard content solution is injected into the second lane in an equal amount. This solution is the maximum heavy metal content standard solution allowed by the environment in the specification, and is a precisely known concentration solution prepared by titration. The heavy metal standard content solution contains four heavy metal elements, Cu, Pb, Cd, and Cr, and is treated with the same fluorescent ligand complexation labeling as the solid waste powder heavy metal electrophoresis sample solution, and electrophoresis separation is started.

[0026] After the preset electrophoresis time is reached, the power is turned off, and the fluorescent imaging device of the composite system is turned on to detect the specific complex of the metal to obtain the length L of each band in the electrophoresis spectrum. ij ; After background correction to remove non-specific fluorescence signals, record the fluorescence signal intensity Q of each band ij, where i is the lane number, i=1,2; j is the color band number, j=1,2,3,4; the test index data is imported into ImageJ image analysis software, and the fluorescence intensity distribution diagram of the heavy metal leaching data of the first lane and the fluorescence intensity distribution diagram of the heavy metal standard data of the second lane are respectively drawn with length as the horizontal axis and fluorescence intensity as the vertical axis.

[0027] S3. Based on the test index data, a specific evaluation method is used to divide the hazard level, and the fluorescence intensity distribution diagram of the heavy metal standard data is integrated to obtain the result heavy metal standard data m 标准j As shown in Table 5, the fluorescence intensity distribution diagram of heavy metal leaching data was integrated to obtain the result of heavy metal leaching data m 1j As shown in Table 6, j is the number of the color band, j=1,2,3,4: Table 5: Heavy metal standard data Table 6: Heavy metal leaching data Calculate the difference M of heavy metal leaching data j , and convert to obtain the difference in heavy metal environmental concentration C j The specific results are shown in Table 7: Table 7: Conversion results of heavy metal environmental concentration differences Combining all parameters, the hazard index HI is calculated. The specific calculation results are shown in Table 8: Table 8: Hazard index calculation results In this embodiment, according to the hazard index calculation results, the hazard index of this batch of solid waste powder is 372.05, which is in the range of 300≤HI<400, that is, it is classified as not suitable for engineering utilization and needs to improve the treatment plan. j It can be seen that this batch of solid waste powder materials needs to be treated to reduce the concentration of Pb and Cd elements.

[0028] In summary, the heavy metal content of solid waste powder can be graded and visualized at the powder particle scale for more accurate and scientific quantitative evaluation and analysis; this method can simultaneously determine a variety of heavy metal elements in solid waste powder, and visualize the heavy metal content to simplify the analysis results; at the same time, new evaluation indicators are introduced on the basis of traditional evaluation methods, and various influencing factors are taken into account, providing relevant scientific basis and technical support for improving the efficiency of rapid decision-making and rationality of treatment of solid waste powder materials at construction sites.

[0029] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the present invention.

Claims

1. A method for determining the heavy metal content of solid waste powder, characterized in that: The following steps are included: S1. Pre-treating solid waste powder, adding chemical reagents to a mother liquor preparation reaction tank to leach heavy metal elements; adding specific element color developing reagents to obtain specific metal complexes of each heavy metal element after fluorescent labeling; S2. Use an electrophoresis pool fluorescence detection composite system to perform electrophoretic separation on the heavy metal complexes and perform fluorescence detection to obtain test index data; S3. Use specific evaluation methods based on test index data to classify hazard levels and guide subsequent solid waste powder disposal.

2. The method for determining the heavy metal content of solid waste powder according to claim 1, characterized in that: In step S1, the electrophoresis pool fluorescence detection composite system comprises an electrophoresis device (1), a fluorescence detection system (2) arranged at the bottom of the electrophoresis pool, and a numerical control unit (13) arranged below the fluorescence detection system; The electrophoresis device (1) is provided with a buffer addition outlet (12) at the front side wall of the outer wall, and an electrophoresis sample pool replacement position (11) is provided at the right side wall. The electrophoresis device (1) comprises an electrophoresis sample pool (3), and positive and negative electrophoresis sample pool electrodes (4) are provided at both ends of the sample pool. Lead wires from the electrophoresis sample pool electrodes (4) are connected to an electrophoresis device power supply (5); The fluorescence detection system (2) comprises a fluorescence marker excitation layer (6) and a high-precision fluorescence detection system (7); the fluorescence marker excitation layer (6) is arranged at the bottom of the electrophoresis sample pool (3), and the electrophoresis sample pool (3) and the fluorescence marker excitation layer (6) are separated by a high-transmittance water-impermeable layer (8); the fluorescence marker excitation layer (6) is connected and arranged above the high-precision fluorescence detection system (7), and the high-precision fluorescence detection system (7) comprises a plurality of high-precision fluorescence detection cameras (9); The numerical control unit (13) is arranged below the fluorescence detection system (2) and the electrophoresis device power supply (5), and the numerical control unit (13) and the fluorescence detection system (2) are connected via a data transmission conduit (10).

3. The method for determining the heavy metal content of solid waste powder according to claim 1, characterized in that: In step S1, the method for pre-treating the solid waste powder includes: sampling the solid waste powder by a quartering method; placing a batch of solid waste powder into a vibrating sieve machine for vibrating and mixing evenly, spreading the mixed solid waste powder into a square thin layer of uniform thickness, dividing it into four equal parts by a cross cutting method, and taking two parts on the diagonal line for further mixing; repeating this process until the sample weight is 500-600g; The solid waste powder is ground, the sample is added into a ball mill, alumina ceramic balls are selected as grinding media, the grinding ball size is selected to be 1-5 mm, the ball-to-material ratio is set to 10:1, the rotation speed is set to 300-500 rpm / min, and the grinding time is set to 30-40 min; The ground solid waste powder sample is subjected to heavy metal element leaching, and a 3-5 mol / L hydrochloric acid solution is selected as the leaching reagent, and the leaching time is set to 24 h. After reaching the predetermined leaching time, a 0.45 μm microporous filter membrane is used to filter the leaching solution to obtain a high leaching amount of heavy metals in the solid waste powder; The heavy metals in the solid waste powder are subjected to color development treatment, and a fluorescently labeled heavy metal complex ligand is added to the high leaching amount solution of the heavy metals in the solid waste powder. The reagents used are specifically: 5mmol / L 1,10-phenanthroline reagent was used for specific complex labeling of Cu, with an excitation wavelength of 370nm and an emission wavelength of 520nm; 1 μmol / L LeadmiumGreen reagent was used to specifically complex Pb, with an excitation wavelength of 490 nm and an emission wavelength of 520 nm; Cadmium-specific fluorophore at 5 μmol / L was used to specifically complex and label Cd, with an excitation wavelength of 488 nm and an emission wavelength of 520 nm; 1mmol / L AlizarinRedS was used to specifically complex Cr, with an excitation wavelength of 430nm and an emission wavelength of 560nm; The ligand reagents used are mixed and added to the high leaching amount solution of heavy metals in solid waste powder, and incubated for 40-60 minutes to ensure that the heavy metal elements are completely complexed; after the complex incubation is completed, the obtained sample solution is subjected to SPE solid phase extraction operation to separate the excess ligand and heavy metal complex; The specific technical parameters for the implementation of solid phase extraction are as follows: cation exchange resin is selected as the adsorbent, methanol is selected as the activation pretreatment reagent, and 2% by mass HCl solution is used as the elution solvent; the sample loading flow rate during solid phase extraction is limited to 1~2ml / min; the eluent is collected and subsequently heated and concentrated to obtain a solid waste powder heavy metal electrophoresis sample solution.

4. The method for determining the heavy metal content of solid waste powder according to claim 1, characterized in that: In step S2, the electrophoretic cell fluorescence detection composite system is used to perform electrophoretic separation on the heavy metal complexes as follows: The collected solid waste powder heavy metal electrophoresis sample solution is added to the electrophoresis pool of the composite system for gel electrophoresis, and the gel is selected as 15% polyacrylamide gel; the buffer is selected as phosphate buffer PBS; HCl with a mass fraction of 0.1% is used to adjust the pH value, and the pH value of the electrophoresis sample pool is adjusted to 5.5-6.0; the electrophoresis voltage is set to 100-120V; the electrophoresis time is set to 30-60min; the electrophoresis pool comprises two lanes, the solid waste powder heavy metal electrophoresis sample solution is injected into the first lane, and the same amount of heavy metal standard content solution is injected into the second lane. This solution is the maximum heavy metal content standard solution allowed by the environment in the specification, and is a precisely known concentration solution prepared by titration. The heavy metal standard content solution contains four heavy metal elements of Cu, Pb, Cd, and Cr, and is treated with the same fluorescent ligand complexation labeling as the solid waste powder heavy metal electrophoresis sample solution, and electrophoresis separation is started; In step S2, the test index data is obtained by turning off the power supply after the preset electrophoresis time is reached, turning on the fluorescent imaging device of the composite system to detect the specific complex of the metal, and obtaining the length L of each band in the electrophoresis spectrum. ij ; After background correction to remove non-specific fluorescence signals, record the fluorescence signal intensity Q of each band ij , where i is the lane number, i=1,2; j is the color band number, j=1,2,3,4; the test index data is imported into ImageJ image analysis software, and the fluorescence intensity distribution diagram of the heavy metal leaching data of the first lane and the fluorescence intensity distribution diagram of the heavy metal standard data of the second lane are respectively drawn with length as the horizontal axis and fluorescence intensity as the vertical axis.

5. The method for determining the heavy metal content of solid waste powder according to claim 1, characterized in that: In step S3, the specific evaluation method for dividing the hazard level according to the test index data is as follows: using image processing software to integrate the fluorescence intensity distribution diagram of the heavy metal standard data, and the result is defined as the heavy metal standard data m 标准j , where the integral limit is the length L of each strip 2j , different bands corresponding to different elements are integrated respectively; similarly, the fluorescence intensity distribution diagram of heavy metal leaching data is integrated, and the result is defined as the heavy metal leaching data m 1j , where j is the number of the color band, j=1,2,3,4; Definition of heavy metal leaching data difference M j , and its calculation formula is as follows: ； Where: M j is the difference of heavy metal leaching data; m 1j is the heavy metal leaching data of the jth band in the first lane; m 标准j is the heavy metal standard data of the jth band in the second lane; where j=1,2,3,4; Definition of heavy metal environmental concentration difference C j , C j With M j The specific relationship is: when M j When ≤0, C j =0, when M j >0, C j =M j ; The characteristic of the classification of danger levels is to calculate the comprehensive evaluation index hazard index HI, and its calculation formula is as follows: ； Where: HI is the hazard index; C j is the heavy metal environmental difference; R j is the hazard level coefficient of the jth element, R j To set the danger level for each heavy metal element according to the content requirements of various elements in the "Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard" GB15618-2018 and the "Drinking Water Hygiene Standard" GB5749-2022; The subsequent treatment of solid waste powder is guided by the hazard index HI, specifically: (1) HI<100: suitable for resource utilization; (2) 100≤HI<300: more suitable, but needs to be evaluated carefully; (3) 300≤HI<400: not suitable, treatment plan needs to be improved; (4) HI ≥ 400: Not suitable for resource utilization and requires safe treatment.

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