Method for evaluating asphalt adsorption performance of solid waste powder material

Abstract

The invention discloses a method for evaluating the asphalt adsorption performance of a solid waste powder material, and relates to the technical field of evaluation of the adsorption performance of the powder material on an asphalt material.The method comprises the steps that the solid waste powder material is treated, and the non-agglomerated accumulation state of a powder material asphalt adsorption performance characterization quantitative test piece is obtained; collecting solid waste powder particles with different asphalt adsorption capacities, and preparing a separated state of the powder material asphalt adsorption performance characterization quantitative test piece; screening solid waste powder particle test pieces with asphalt adsorption performance; and obtaining the asphalt adsorption mass of a single particle, determining the effective adsorption area of the solid waste powder material, and calculating adsorption parameters to evaluate the adsorption performance of the solid waste powder material on the asphalt. The method can quantitatively evaluate the adsorption performance of the solid waste powder material to the asphalt, so that quantitative analysis on the adsorption efficiency and interaction degree of the solid waste powder material and the asphalt cement is realized.

Description

Technical Field

[0001] The invention relates to the technical field of evaluating the adsorption performance of powdery materials on asphalt materials, and in particular to a method for evaluating the asphalt adsorption performance of solid waste powdery materials. Background Art

[0002] Solid waste powder materials are often used as fillers in large quantities in asphalt pavement materials. However, the interaction between different types of solid waste powder materials and asphalt directly affects the various properties of asphalt pavement materials. Based on this, evaluating the adsorption performance of solid waste powder materials on asphalt binders is of great significance for clarifying the interaction between the two, which will provide a basis and guarantee for the good road performance of solid waste-asphalt pavement materials.

[0003] Nowadays, the evaluation of the adsorption performance of solid waste powdery materials on asphalt mainly focuses on the physical adsorption performance of powdery materials, such as: 1. Evaluating the adhesion performance of solid waste powdery materials by measuring the change in the adsorption amount of asphalt before and after water replacement; 2. Using a spectrophotometer to measure the change in the transmittance of asphalt-toluene solution to indirectly reflect the change in asphalt concentration, thereby evaluating the adsorption performance of solid waste powdery materials on asphalt; 3. The stirred water net adsorption method, which is based on the SHRP research plan, stirs water to make the asphalt film on the surface of solid waste powdery materials peel off and re-enter the solution, and uses a spectrophotometer to measure the change in solution transmittance to evaluate the adsorption performance. However, the existing evaluation methods still have certain problems or defects. First, the existing test methods have high equipment costs and complex operations, making them difficult to promote in a wide range of practical applications. Second, evaluating the adsorption capacity of powdery materials through physical and chemical treatments may affect the adsorption capacity of the powdery materials themselves, resulting in a large deviation between the adsorption capacity and the actual performance. Furthermore, the existing research on the characterization parameters of adsorption performance is not accurate enough, and the evaluation method is relatively single, which cannot fully evaluate the adsorption performance of solid waste powdery materials on asphalt materials. Therefore, it is still urgent to propose a reasonable and effective evaluation method for the adsorption performance of solid waste powdery materials on asphalt, so as to provide relevant scientific basis and technical support for improving the resource utilization of solid waste powdery materials in asphalt pavement materials. Summary of the invention

[0004] The present invention is proposed in view of the problems existing in the evaluation of the asphalt adsorption performance of existing solid waste powdery materials.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: In a first aspect, an embodiment of the present invention provides a method for evaluating the asphalt adsorption performance of solid waste powdery materials, which comprises the following steps: S1. Treat solid waste powdery materials, use a centrifugal separation device to make the solid waste powdery materials absorb the asphalt binder dispersed in the emulsified asphalt, and obtain the non-agglomerated accumulation state of the powdery materials asphalt adsorption performance characterization quantitative test piece; S2. Start the centrifugal device to collect solid waste powder particles with different asphalt adsorption amounts, and prepare the separation state of the powder material asphalt adsorption performance characterization quantitative test pieces; S3. Analyze the particle size composition of different solid waste powder particles based on particle size classification, calculate the quantity and mass of particles with different particle size compositions, and screen solid waste powder particle specimens with asphalt adsorption performance; S4. Obtain the asphalt adsorption mass of a single particle, determine the effective adsorption area of ​​the solid waste powdery material, and calculate the adsorption parameters to evaluate the adsorption performance of the solid waste powdery material for asphalt.

[0006] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, wherein: in the step S1, the centrifugal separation device includes a rotary power device, a container arranged on the top of the rotary power device, and a collection bin arranged at the bottom of the container; A group of stirring rods are circumferentially fixed to the top of the collecting bin, the inner wall of the container is provided with asphalt height scale lines, collectors are provided on both sides of the outside of the container, each connecting part between the collector and the container is provided with a one-way filter, storage bins are provided at the bottom ends of both sides of the container, the connecting ends of the storage bins are connected to air ducts for introducing compressed air, a compressed air control air pressure valve is installed at the end of the air duct away from the container, and a group of pressure relief holes are opened at the top of the container.

[0007] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powder materials of the present invention, wherein: in step S1, the solid waste powder materials to be treated include waste incineration fly ash, slag powder and fly ash, and the particle size range is 4-45 μm, and the density range is 1.0-3.0 g / cm 3 ; The method for treating solid waste powdery materials comprises: weighing 100-150 g of solid waste powdery materials, adding distilled water to the solid waste powdery materials for multiple times to wash, placing the solid waste powdery materials in an oven for drying at 160° C. for 40-60 min after washing, taking out the powdery materials after drying, and spreading them evenly on a cleaned sieve plate, wherein the sieve hole size of the sieve plate is 325 meshes, using a vibrating sieve shaker to vibrate and screen the powdery materials, and taking out the sieved solid waste powdery materials after screening.

[0008] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, wherein: in the step S1, a centrifugal separation device is used to make the powdery material absorb the asphalt material dispersed in the emulsified asphalt, and the specific steps include: weighing the emulsified asphalt and placing it in a beaker, and then pouring it into the container of the conical centrifugal separation device, the height of the added emulsified asphalt is higher than the asphalt height scale line calibrated in the centrifugal separation device, and the total amount of emulsified asphalt is 300-500ml, using a baffle to cover the collector inlet on the inner wall of the device, and the 100-150g solid waste powdery material after screening is evenly divided and placed in the storage bins at both ends respectively, and compressed air is sprayed into the storage bin, and the compressed air drives the solid waste powdery material into the container filled with emulsified asphalt, and the rotating power device at the bottom of the device is simultaneously turned on to rotate the stirring rod, and then the powdery material is prompted to absorb the asphalt binder dispersed in the emulsified asphalt, and the total adsorption time is set to 20-30min, and the non-agglomerated accumulation state of the powdery material asphalt adsorption performance characterization quantitative test piece is obtained; Among them, the turning-on time of the rotating power equipment is set to 10 minutes, the injection flow rate of the compressed air is set to 20-30L / min, and the injection time is set to 5 minutes.

[0009] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, in step S2, the step of preparing a test piece for characterizing the asphalt adsorption performance comprises: Start the centrifugal function of the centrifugal separation device, set the speed of the centrifugal separation device to 6000-8000rpm, and set the time to 10-15min. The powdery material particles with different asphalt adsorption amounts are separated into collectors at different heights under the action of centrifugal force. At the same time, large particles of asphalt-powder particles will settle into the collection bin at the bottom of the instrument under the action of gravity. After the centrifugation time is reached, the centrifugal separation device is stopped, and the asphalt-silt particles in the collection bin are placed in different clean containers respectively. The asphalt-silt particles obtained from different collectors are poured into the oscillator respectively, and 50 ml of 0.1% sodium octyl polyoxyethylene ether sulfate surfactant is evenly poured in, and the oscillator is started. The oscillation time is set to 3 to 5 minutes to fully mix the surfactant and the particles; After the shaking is completed, the mixture in the shaker is evenly poured onto the organic microfiltration membrane, and the active agent and the asphalt adsorption characterization particles are filtered and separated. The organic microfiltration membrane is a polytetrafluoroethylene membrane. After filtration, the asphalt adsorption characterization particles are obtained, and the asphalt adsorption performance test of the solid waste powder material is completed, and the separation state of the powder material asphalt adsorption performance characterization quantitative specimen is obtained.

[0010] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, in step S3, the particle size composition analysis method of different solid waste powdery particles includes: Solid waste powder particles with extreme particle sizes are eliminated, and the separation state of the powder material asphalt adsorption performance characterization and quantification test pieces is analyzed using a laser particle size analyzer. The particle size range of solid waste adsorption particles in the powder material asphalt adsorption performance characterization and quantification test pieces in the collector and the collection bin is obtained, and the extreme particle size is defined. The particle size mean μ and standard deviation σ of the solid waste adsorption particles are calculated, where the extreme particle size is defined as: the normal particle size range is expressed as [μ-2σ, μ+2σ], and the particle size value beyond this particle size range is defined as the extreme particle size; The separation state of the powdery material asphalt adsorption performance characterization quantification specimen was flattened and photographed using a camera to obtain the number of particles of different particle sizes. , remove the extreme particle size particles to obtain the average adsorption performance characterization specimens, and after completing the counting, weigh the average adsorption performance characterization specimens one by one to obtain the mass of each average adsorption performance characterization specimen ; Among them, i is the number corresponding to multiple collectors and a collection bin, and j is the number of the particle involved in the counting.

[0011] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, in step S4, the calculation method of evaluating the asphalt adsorption performance of solid waste powdery materials by adsorption parameters includes: The average adsorption performance characterization specimens collected from different collectors and collection bins were placed into a furnace one by one and incinerated at 700°C for 60 to 90 minutes, then cooled and weighed using an electronic balance to obtain the mass of the single solid waste powder material after incineration. , and then calculate the asphalt adsorption mass of a single particle , the calculation formula is expressed as: ; In the formula, is the asphalt adsorption mass of a single particle, The average adsorption performance characterizes the quality of the specimen. It is the mass of single solid waste powder material after incineration.

[0012] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, in step S4, the method for determining the effective area of ​​the solid waste powdery materials includes: The powdery material is placed in a nitrogen adsorption instrument for low-temperature nitrogen adsorption. The cooling system of the nitrogen adsorption instrument will cool down the sample pool. Nitrogen is passed into the sample pool, and the nitrogen adsorption amount under different nitrogen partial pressures is recorded. The specific surface area of ​​the sample is calculated using the following formula: ; In the formula, V is the volume of gas adsorbed by the powdery material, P is the actual pressure of nitrogen in the adsorption instrument, P0 is the saturated vapor pressure of nitrogen, which is set to 0.1-0.2Pa, and C is the BET constant, which is obtained through linear fitting in the experiment. is the volume of a single molecular layer of nitrogen, ranging from 0.2 to 0.3 cm 3 / g; Then, the nitrogen volume of the monolayer and the BET constant were linearly fitted, and the specific values ​​were obtained through computer graphics to calculate the adsorption specific surface area of ​​the single particle solid waste powder material. The calculation formula is: ; In the formula, is the adsorption specific surface area of ​​a single particle of solid waste powder material, N is Avogadro's constant, A is the surface area of ​​gas molecules, and M is the molar mass of the gas; Then calculate the adsorption amount of solid waste powder asphalt, the calculation formula is expressed as: ; In the formula, is the asphalt adsorption capacity of a single particle of solid waste powder, in mg / mm 2 .

[0013] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, in step S4, the step of calculating the adsorption parameter to evaluate the asphalt adsorption performance of solid waste powdery materials includes: The particles of different sizes were rearranged in order from large to small according to the asphalt adsorption capacity; Define the particle number in each collector and collection bin as x i , where x is the rearranged particle number; Define the number as x i The asphalt adsorption amount corresponding to the particle is y i , where y is the asphalt adsorption amount; Substitute the data into the coordinate system to obtain the scatter plot of the adsorption amount of granular asphalt in different collectors and collection bins; Perform a linear fit on each scatter plot and calculate R 2 , when the fitting result is R 2 ≥0.95, the fitting degree is good. 2When <0.95, the extreme points on the scatter plot of the adsorption of granular asphalt are defined, the extreme points on the scatter plot of the adsorption of granular asphalt are removed, and the linear fitting is re-performed and R is calculated. 2 , repeat the elimination operation until R 2 ≥0.95, the remaining data points are used as the basic data for calculating the asphalt adsorption capacity; Obtain the range of asphalt adsorption capacity of solid waste powder particles in different collectors and collection bins; Four asphalt adsorption capacity range data sets are obtained by calculation, and they are arranged from small to large according to the minimum value of each data set, and the four asphalt adsorption capacity range data sets after arrangement are numbered respectively; First, the intersection of the data set numbered as range 1 and the data set numbered as range 2 is taken as set A, and the intersection of the data set numbered as range 3 and the data set numbered as range 4 is taken as set B. The steps for obtaining the average adsorption capacity range of solid waste powder particles include: If both set A and set B are empty, the data sets in range 1 and range 4 are discarded, the data sets in range 2 and range 3 are retained, and the calculation basic data contained in the data sets in range 2 and range 3 are merged to obtain a new data set; If set A is empty and set B is not empty, the data set in range 1 is discarded, the data set in range 2 and set B are retained, and the data set in range 2 and the calculation basic data contained in set B are merged to obtain a new data set; If set B is empty and set A is not empty, the range 4 data set is discarded, and the data sets of set A and range 3 are retained. The data sets of range 3 and the calculation basic data contained in set B are merged to obtain a new data set. If both set A and set B are not empty, then the union of set A and set B is directly taken to merge the basic data to obtain a new data set; For the new data set, the minimum adsorption amount is set equal to the minimum adsorption amount in the calculation base data in the retained data set, and the maximum adsorption amount is set equal to the maximum adsorption amount in the calculation base data in the retained data set, so as to obtain the average adsorption capacity range and median of solid waste powdery particles.

[0014] The beneficial effects of the present invention are: more accurate and scientific quantitative evaluation and analysis of the asphalt adsorption performance of solid waste powdery materials at the powdery particle scale; and the method can simultaneously evaluate the asphalt adsorption performance of particles of different particle sizes of the same material, and calculate the average adsorption performance of the material through quantitative analysis; at the same time, new evaluation indicators are introduced on the basis of traditional evaluation methods, and the influencing factors of various indicators are taken into account, so as to provide a scientific basis for evaluating the adsorption performance of solid waste materials on asphalt materials and the practicality, economy and accuracy of the selection of asphalt mixture fillers in actual production. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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 evaluating the asphalt adsorption performance of solid waste powdery materials.

[0016] Figure 2 This is a structural diagram of a centrifugal separation device.

[0017] Figure 3 Schematic diagram of data set processing for the calculation of the basic data range of the evaluation method for the asphalt adsorption performance of solid waste powdery materials.

[0018] Figure 4 Schematic diagram of asphalt adsorption mass of characterizing specimens for evaluating the asphalt adsorption performance of solid waste powdery materials.

[0019] Figure 5 Schematic diagram of the asphalt adsorption specific surface area of ​​the characterization specimen for the evaluation method of asphalt adsorption performance of solid waste powdery materials.

[0020] Figure 6 Schematic diagram of the basic data range data set for the evaluation method of asphalt adsorption performance of solid waste powdery materials. DETAILED DESCRIPTION

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] Example 1 First of all, it should be noted that the powder sample selected in this embodiment comes from the fly ash incinerated by the grate furnace of a waste incineration plant in Zhongshan. The main incineration material is urban domestic waste, and its particle size range is 4-45 μm, and the density range is 1.0-3.0 g / cm 3 .

[0028] Reference Figure 1 to Figure 6 , which is the first embodiment of the present invention, provides a method for evaluating the asphalt adsorption performance of solid waste powdery materials, comprising the following steps: S1. Treat solid waste powdery materials, use a centrifugal separation device to make the solid waste powdery materials absorb the asphalt binder dispersed in the emulsified asphalt, and obtain the non-agglomerated accumulation state of the powdery materials to characterize the asphalt adsorption performance of the quantitative specimens.

[0029] The method for treating solid waste powdery materials includes: weighing 100-150g of solid waste powdery materials, adding distilled water to the solid waste powdery materials for multiple times to wash, placing the solid waste powdery materials in an oven at 160°C for drying for 40-60min after washing, taking out the powdery materials after drying, spreading them evenly on a cleaned sieve plate, the sieve hole size of the sieve plate is 325 mesh (45μm), using a vibrating sieve machine to vibrate and screen the powdery materials, and taking out the sieved solid waste powdery materials after screening.

[0030] The centrifugal separation device comprises a rotary power device 1, a container 11 arranged at the top of the rotary power device 1, and a collection bin 6 arranged at the bottom of the container 11; A group of stirring rods 2 are circumferentially fixed to the top of the collecting bin 6, an inner wall of the material container 11 is provided with asphalt height scale lines 3, collectors 4 are provided on both sides of the outside of the material container 11, and each connecting portion between the collector 4 and the material container 11 is provided with a one-way filter 5, and storage bins 7 are provided at the bottom ends of both sides of the material container 11, and the connecting ends of the storage bins 7 are connected to air ducts 10 for introducing compressed air, and a compressed air control air pressure valve 8 is installed at the end of the air duct 10 away from the material container 11, and a group of pressure relief holes 9 are opened at the top of the material container 11.

[0031] The centrifugal separation device allows the powdery material to absorb the asphalt material dispersed in the emulsified asphalt. The functions of the centrifugal separation device include the solid waste powdery material absorbing the asphalt binder and the centrifugal classification adsorption particles. The centrifugal separation device is made of high-strength aluminum alloy. The emulsified asphalt used is specifically slow-cracking emulsified asphalt. According to JTG E20-2019 "Test Procedures for Asphalt and Asphalt Mixtures for Highway Engineering", the demulsification time is 6~8min; A centrifugal separation device is used to make the powdery material absorb the asphalt material dispersed in the emulsified asphalt. The specific steps include: weighing the emulsified asphalt and placing it in a beaker, and then pouring it into the container 11 of the conical centrifugal separation device, the height of the added emulsified asphalt is higher than the asphalt height scale line 3 calibrated in the centrifugal separation device, and the total amount of emulsified asphalt is 300-500ml, using a baffle to cover the entrance of the collector 4 on the inner wall of the device, and the 100-150g solid waste powdery material after screening is evenly divided and placed in the storage bins 7 at both ends respectively, and compressed air is sprayed into the storage bin 7. The compressed air drives the solid waste powdery material into the container 11 filled with emulsified asphalt, and the rotating power device 1 at the bottom of the device is simultaneously turned on to rotate the stirring rod 2, and then the powdery material is caused to absorb the asphalt binder dispersed in the emulsified asphalt, and the total adsorption time is set to 20-30min, and the non-agglomerated accumulation state of the powdery material asphalt adsorption performance characterization quantitative test piece is obtained; The start-up time of the rotary power device 1 is set to 10 minutes, the injection flow rate of the compressed air is set to 20-30 L / min, and the injection time is set to 5 minutes.

[0032] S2. Start the centrifugal device to collect solid waste powder particles with different asphalt adsorption amounts, and prepare the separation state of the powdery material asphalt adsorption performance characterization quantitative test pieces.

[0033] In step S2, the steps of preparing the test piece for characterizing the performance of asphalt adsorption include: Start the centrifugal function of the centrifugal separation device, set the speed of the centrifugal separation device to 6000-8000rpm, and the time to 10-15min. In this embodiment, the speed is set to 6000rpm and the time is set to 15min. The powdery material particles with different asphalt adsorption amounts are separated into collectors 4 at different heights under the action of centrifugal force, and the large asphalt-powder particles will settle into the collection bin 6 at the bottom of the instrument under the action of gravity; After the centrifugation time is reached, the centrifugal separation device is stopped, and the asphalt-silt particles in the collection bin 6 are placed in different clean containers respectively, and the asphalt-silt particles obtained from different collectors 4 are poured into the oscillator respectively, and 50 ml of 0.1% sodium octyl polyoxyethylene ether sulfate surfactant is evenly poured in, and the oscillator is started, and the oscillation time is set to 3 to 5 minutes, and the time in this embodiment is 4 minutes, so that the surfactant and the particles are fully mixed; After the shaking is completed, the mixture in the shaker is evenly poured onto the organic microfiltration membrane, and the active agent and the asphalt adsorption characterization particles are filtered and separated. The organic microfiltration membrane is a polytetrafluoroethylene membrane. After filtration, the asphalt adsorption characterization particles are obtained, and the asphalt adsorption performance test of the solid waste powder material is completed, and the separation state of the powder material asphalt adsorption performance characterization quantitative specimen is obtained.

[0034] S3. Analyze the particle size composition of different solid waste powder particles based on particle size classification, calculate the quantity and mass of particles with different particle size compositions, and screen solid waste powder particle specimens with asphalt adsorption performance.

[0035] In step S3, the particle size composition analysis method of different solid waste powder particles includes: Since the adsorption amount of asphalt by powdery materials is different, the adsorption amount parameters have a certain degree of discreteness. In order to evaluate the asphalt adsorption amount more accurately, firstly, the solid waste powdery particles with extreme particle sizes are eliminated, and the separation state of the powdery material asphalt adsorption performance characterization and quantification test piece is used for particle size analysis, and the particle size range of the solid waste adsorption particles in the powdery material asphalt adsorption performance characterization and quantification test piece in the collector 4 and the collection bin 6 is obtained, and the extreme particle size is defined. The particle size mean μ and standard deviation σ of the solid waste adsorption particles are calculated, wherein the extreme particle size is defined as: the normal particle size range is expressed as [μ-2σ, μ+2σ], and the particle size value beyond this particle size range is defined as the extreme particle size; The separation state of the powdery material asphalt adsorption performance characterization and quantification test piece was flattened and photographed with a camera. The image was imported into MATLAB software and the imbinarize function was used for image binarization. The image processing tool (Image Processing Toolbox) provided by MATLAB was used to count the particles in the binary image to obtain the number of particles of different particle sizes. ; After removing the extreme value particle size particles, that is, the particles outside the particle size range of [μ-2σ, μ+2σ], the average adsorption performance characterization specimen can be obtained after the collectors 4 and the collection bins 6 are removed, wherein the final removal results are shown in Table 1; Table 1: Average adsorption performance characterization specimen calculation table serial number Characterize the total number of particles / piece Average particle size / mm Particle size standard deviation Total number of particles removed 1 24 4.2 0.2 2 2 37 6.8 0.24 1 3 34 8.4 0.38 0 4 33 10.6 0.46 0 After the counting is completed, the mass of the average adsorption performance characterization specimens is weighed one by one, and the mass of the particles is weighed using a high-precision electronic balance with a sensitivity of 0.01 mg to obtain the mass of each average adsorption performance characterization specimen. ; Here, i is the number corresponding to a plurality of collectors 4 and a collection bin 6, and j is the number of the particle involved in the counting.

[0036] S4. Obtain the asphalt adsorption mass of a single particle, determine the effective adsorption area of ​​the solid waste powdery material, and calculate the adsorption parameters to evaluate the adsorption performance of the solid waste powdery material for asphalt.

[0037] In step S4, the calculation method of evaluating the adsorption performance of solid waste powdery materials to asphalt by adsorption parameters includes: The average adsorption performance characterization specimens collected in different collectors 4 and collection bins 6 are placed in a furnace one by one and burned at 700°C for 60 to 90 minutes. In this embodiment, the duration is 80 minutes to ensure that all the adsorbed asphalt on the characterization specimens is completely burned. Then, they are cooled and weighed using an electronic balance to obtain the mass of the single solid waste powder material after incineration. , and then calculate the asphalt adsorption mass of a single particle , the calculation formula is expressed as: ; In the formula, is the asphalt adsorption mass of a single particle, The average adsorption performance characterizes the quality of the specimen. It is the mass of the powdery material of a single solid waste after incineration; In this embodiment, refer to Figure 4 As shown, the line segment corresponding to the black collector is attached Figure 2 In the middle, the collector 4 is located at the uppermost end; Figure 4 The line segment corresponding to the red collector is the Figure 2 A collector 4 located in the second layer; Figure 4 The line segment corresponding to the blue collector is the Figure 2 The collector 4 is located on the third layer.

[0038] The methods for determining the effective area of ​​solid waste powdery materials include: The Brunner-Emmert-Taylor method (BET specific surface area) was used to measure the effective adsorption area of ​​the powdery material. Nitrogen was selected as the adsorption gas and the instrument used was a nitrogen adsorption instrument. After calibrating the instrument, the powdery material was placed in the nitrogen adsorption instrument for low-temperature nitrogen adsorption. The cooling system of the nitrogen adsorption instrument would cool the sample pool to a specific temperature of -196°C. Nitrogen was passed into the sample pool and adsorbed onto the sample surface. The nitrogen adsorption amount under different nitrogen partial pressures was recorded. The adsorption and desorption processes were performed under different relative pressures (P / P0) to form isothermal adsorption and desorption curves. The relative pressure range of 0.05 < P / P0 < 0.3 was selected for BET analysis to ensure the accuracy of the data and calculate the specific surface area of ​​the sample. The calculation formula is: ; In the formula, V is the volume of gas adsorbed by the powdery material, P is the actual pressure of nitrogen in the adsorption instrument, P0 is the saturated vapor pressure of nitrogen, which is set to 0.1-0.2Pa, and C is the BET constant, which is obtained through linear fitting in the experiment. is the volume of a single molecular layer of nitrogen, ranging from 0.2 to 0.3 cm 3 / g; Then, the nitrogen volume of the monolayer and the BET constant were linearly fitted, and the specific values ​​were obtained through computer graphics to calculate the adsorption specific surface area of ​​the single particle solid waste powder material. The calculation formula is: ; In the formula, is the adsorption specific surface area of ​​a single particle of solid waste powder material, N is Avogadro's constant, which is 6.022×10 23 , A is the surface area of ​​gas molecules, nitrogen is 0.162nm 2 , M is the molar mass of the gas, nitrogen is 28g / mol; In this embodiment, refer to Figure 5 As shown, the line segment corresponding to the black collector is attached Figure 2 In the middle, the collector 4 is located at the uppermost end; Figure 5 The line segment corresponding to the red collector is the Figure 2 A collector 4 located in the second layer; Figure 5 The line segment corresponding to the blue collector is the Figure 2 The collector 4 is located on the third layer.

[0039] Then calculate the adsorption amount of solid waste powder asphalt, the calculation formula is expressed as: ; In the formula, is the asphalt adsorption capacity of a single particle of solid waste powder, in mg / mm 2 .

[0040] The steps of calculating the adsorption parameters to evaluate the adsorption performance of solid waste powder materials to asphalt include: The particles of different sizes were rearranged in order from large to small according to the asphalt adsorption capacity; Define the particle number in each collector 4 and collection bin 6 as x i , where x is the rearranged particle number; Define the number as x i The asphalt adsorption amount corresponding to the particle is y i , where y is the asphalt adsorption amount; Substitute the data into the coordinate system to obtain the scatter plot of the particle asphalt adsorption amount of different collectors 4 and collection bins 6; Perform a linear fit on each scatter plot and calculate R 2 , when the fitting result is R 2 ≥0.95, the fitting degree is good. 2 When <0.95, the extreme points on the scatter plot of the adsorption of granular asphalt are defined, the extreme points on the scatter plot of the adsorption of granular asphalt are removed, and the linear fitting is re-performed and R is calculated. 2 , repeat the elimination operation until R 2 ≥0.95, the remaining data points are used as the basic data for calculating the asphalt adsorption capacity, and all y values ​​on the scatter plot of the particle asphalt adsorption capacity are averaged. As well as the calculation of the standard deviation β, the extreme value is defined as based on the principle of standard deviation, and the normal range is expressed as [ -2β, +2β], and the y value that is not in this range is defined as the extreme point on the scatter plot. The basic data result table of asphalt adsorption capacity calculation is shown in Table 2; Table 2: Detailed data for calculating asphalt adsorption capacity serial number Data minimum value / mg·mm-2 Maximum value of data / mg·mm-2 Total number of data points Fitting equation Goodness of fit / R2 1 1.48 2.51 24 y = 0.041x + 1.4164 0.98 2 23.47 37.97 34 y = 0.392x + 23.066 0.98 3 32.79 71.73 29 y = 1.1902x + 28.564 0.96 4 64.96 99.43 26 y = 1.0724x + 64.818 0.96 Obtaining the asphalt adsorption capacity range of solid waste powder particles in different collectors 4 and collection bins 6, the specific steps include: for the same collector 4 or collection bin 6, setting the minimum adsorption amount equal to the minimum adsorption amount in the basic data calculated for the collector 4 or collection bin 6, and the maximum adsorption amount equal to the maximum adsorption amount in the basic data calculated for the collector 4 or collection bin 6, and then obtaining the asphalt adsorption capacity range of solid waste powder particles in the collector 4 or collection bin 6; Four asphalt adsorption capacity range data sets are obtained by calculation, and are arranged from small to large according to the minimum value of each data set. The four arranged asphalt adsorption capacity range data sets are numbered respectively, wherein the asphalt adsorption capacity range data set with the smallest number is range 1, the asphalt adsorption capacity range data set with the second smallest number is range 2, the asphalt adsorption capacity range data set with the third smallest number is range 3, and the asphalt adsorption capacity range data set with the largest number is range 4; First, the intersection of the data set numbered as range 1 and the data set numbered as range 2 is taken as set A, and the intersection of the data set numbered as range 3 and the data set numbered as range 4 is taken as set B. The steps for obtaining the average adsorption capacity range of solid waste powder particles include: If both set A and set B are empty, the data sets in range 1 and range 4 are discarded, the data sets in range 2 and range 3 are retained, and the calculation basic data contained in the data sets in range 2 and range 3 are merged to obtain a new data set; If set A is empty and set B is not empty, the data set in range 1 is discarded, the data set in range 2 and set B are retained, and the data set in range 2 and the calculation basic data contained in set B are merged to obtain a new data set; If set B is empty and set A is not empty, the range 4 data set is discarded, and the data sets of set A and range 3 are retained. The data sets of range 3 and the calculation basic data contained in set B are merged to obtain a new data set. If both set A and set B are not empty, then the union of set A and set B is directly taken to merge the basic data to obtain a new data set; For example, refer to Figure 3 and Figure 6 As shown, Figure 3Schematic diagram of data set processing for calculating basic data range The basic data for calculating asphalt adsorption capacity is processed, and its interval range data set is drawn Figure 6 Schematic diagram of basic data for calculating the adsorption capacity of solid waste powder asphalt in the whole device, Figure 6 It can be seen that set A is an empty set, excluding the range [1.48, 2.51], and there is a data set of range 3 ∩ data set of range 4 = set B, that is, set B = [64.96, 71.73]. If the set A is empty and B is not empty in the rule, the data set of range 1 is discarded, and the data set of range 2 and set B are retained. The calculation basic data contained in the data set of range 2 and set B are merged to obtain a new data set. Therefore, the average adsorption capacity range data set of this type of solid waste powder particles is [23.47, 71.73]; For the new data set, let the minimum adsorption amount be equal to the minimum adsorption amount in the calculation base data in the retained data set, and let the maximum adsorption amount be equal to the maximum adsorption amount in the calculation base data in the retained data set, and obtain the average adsorption capacity range and median of solid waste powder particles; In this embodiment, the median value is calculated as (23.47+71.73) / 2=47.6, that is, median value=47.6 mg / mm 2 .

[0041] In summary, a more accurate and scientific quantitative evaluation and analysis of the asphalt adsorption performance of solid waste powdery materials can be carried out at the powdery particle scale; and this method can simultaneously evaluate the asphalt adsorption performance of particles of different particle sizes of the same material, and calculate the average adsorption performance of the material through quantitative analysis; at the same time, new evaluation indicators are introduced on the basis of traditional evaluation methods, and the influencing factors of various indicators are considered to provide a scientific basis for evaluating the adsorption performance of solid waste materials on asphalt materials and the practicality, economy and accuracy of the selection of asphalt mixture fillers in actual production.

[0042] 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 evaluating the asphalt adsorption performance of solid waste powdery materials, characterized by: The following steps are included: S1. Treat solid waste powdery materials, use a centrifugal separation device to make the solid waste powdery materials absorb the asphalt binder dispersed in the emulsified asphalt, and obtain the non-agglomerated accumulation state of the powdery materials asphalt adsorption performance characterization quantitative test piece; S2. Start the centrifugal device to collect solid waste powder particles with different asphalt adsorption amounts, and prepare the separation state of the powder material asphalt adsorption performance characterization quantitative test pieces; S3. Analyze the particle size composition of different solid waste powder particles based on particle size classification, calculate the quantity and mass of particles with different particle size compositions, and screen solid waste powder particle specimens with asphalt adsorption performance; S4. Obtain the asphalt adsorption mass of a single particle, determine the effective adsorption area of ​​the solid waste powdery material, and calculate the adsorption parameters to evaluate the adsorption performance of the solid waste powdery material for asphalt.

2. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 1, characterized in that: In the step S1, the centrifugal separation device comprises a rotary power device (1), a container (11) arranged at the top of the rotary power device (1), and a collection bin (6) arranged at the bottom of the container (11); A group of stirring rods (2) are fixedly connected to the top of the collecting bin (6) in a circumferential direction. The inner wall of the container (11) is provided with asphalt height scale lines (3). Collectors (4) are provided on both sides of the outside of the container (11). Each connection portion between the collector (4) and the container (11) is provided with a one-way filter (5). Storage bins (7) are provided at the bottom ends of both sides of the container (11). The connection ends of the storage bins (7) are connected with air guide pipes (10) for introducing compressed air. A compressed air control air pressure valve (8) is installed at one end of the air guide pipe (10) away from the container (11). A group of pressure relief holes (9) are provided at the top of the container (11).

3. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 2, characterized in that: In the step S1, the method for processing solid waste powdery materials includes: weighing 100-150g of solid waste powdery materials, adding distilled water to the solid waste powdery materials for multiple times to wash, putting them into an oven at 160°C for drying for 40-60min after washing, taking out the powdery materials after drying, and spreading them evenly on a cleaned sieve plate, the sieve hole size of the sieve plate is 325 mesh, using a vibrating sieve shaker to vibrate and screen the powdery materials, and taking out the sieved solid waste powdery materials after screening.

4. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 3, characterized in that: In step S1, a centrifugal separation device is used to make the powdery material absorb the asphalt material dispersed in the emulsified asphalt. The specific steps include: weighing the emulsified asphalt and placing it in a beaker, pouring it into a container (11) of the conical centrifugal separation device, the height of the added emulsified asphalt is higher than the asphalt height scale line (3) calibrated in the centrifugal separation device, and the total amount of emulsified asphalt is 300-500 ml, using a baffle to cover the inlet of the collector (4) on the inner wall of the device, and discarding 100-150 g of the solid after screening. The solid waste powdery materials are evenly divided and placed in storage bins (7) at both ends respectively. Compressed air is sprayed into the storage bins (7), and the compressed air drives the solid waste powdery materials into the container (11) filled with emulsified asphalt. The rotating power device (1) at the bottom of the device is simultaneously turned on to rotate the stirring rod (2), and then the powdery materials are caused to absorb the asphalt binder dispersed in the emulsified asphalt. The total adsorption time is set to 20 to 30 minutes, and the non-agglomerated accumulation state of the powdery materials asphalt adsorption performance characterization quantitative test piece is obtained; The start time of the rotary power device (1) is set to 10 minutes, the injection flow rate of the compressed air is set to 20 to 30 L / min, and the injection time is set to 5 minutes.

5. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 4, characterized in that: In step S2, the steps of preparing the test piece for characterizing the performance of asphalt adsorption include: The centrifugal function of the centrifugal separation device is started, and the speed of the centrifugal separation device is set to 6000-8000 rpm, and the time is set to 10-15 minutes. Due to the difference in mass of the powdery material particles with different asphalt adsorption amounts, the powdery material particles are separated into collectors (4) at different heights under the action of centrifugal force. At the same time, the large particles of asphalt-powder particles will settle into the collection bin (6) at the bottom of the instrument under the action of gravity; After the centrifugation time is reached, the centrifugal separation device is stopped, and the asphalt-silt particles in the collection bin (6) are placed in different clean containers, and the asphalt-silt particles obtained from different collectors (4) are poured into an oscillator, and 50 ml of 0.1% by mass octyl polyoxyethylene ether sodium sulfate surfactant is evenly poured into it, and the oscillator is started, and the oscillation time is set to 3 to 5 minutes to fully mix the surfactant and the particles; After the shaking is completed, the mixture in the shaker is evenly poured onto the organic microfiltration membrane, and the active agent and the asphalt adsorption characterization particles are filtered and separated. The organic microfiltration membrane is a polytetrafluoroethylene membrane. After filtration, the asphalt adsorption characterization particles are obtained, and the asphalt adsorption performance test of the solid waste powder material is completed, and the separation state of the powder material asphalt adsorption performance characterization quantitative specimen is obtained.

6. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 5, characterized in that: In step S3, the particle size composition analysis method of different solid waste powder particles includes: Solid waste powder particles with extreme particle sizes are eliminated, and a laser particle size analyzer is used to analyze the separation state of the powder material asphalt adsorption performance characterization and quantification test piece, and the particle size range of the solid waste adsorption particles in the powder material asphalt adsorption performance characterization and quantification test piece in the collector (4) and the collection bin (6) is obtained, and the extreme particle size is defined. The particle size mean μ and standard deviation σ of the solid waste adsorption particles are calculated, wherein the extreme particle size is defined as: the normal particle size range is expressed as [μ-2σ, μ+2σ], and the particle size value beyond this particle size range is defined as the extreme particle size; The separation state of the powdery material asphalt adsorption performance characterization quantification test piece is flattened and photographed with a camera to obtain the number of particles of different particle sizes. , remove the extreme particle size particles to obtain the average adsorption performance characterization specimens, and after completing the counting, weigh the average adsorption performance characterization specimens one by one to obtain the mass of each average adsorption performance characterization specimen ; Wherein, i is the number corresponding to the plurality of collectors (4) and a collection bin (6), and j is the number of the particle involved in the counting.

7. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 6, characterized in that: In step S4, the calculation method of evaluating the adsorption performance of solid waste powdery materials to asphalt by adsorption parameters includes: The average adsorption performance characterization test pieces collected in different collectors (4) and collection bins (6) are placed into a furnace one by one and incinerated at 700°C for 60 to 90 minutes, then cooled and weighed using an electronic balance to obtain the mass of the single solid waste powder material after incineration. , and then calculate the asphalt adsorption mass of a single particle , the calculation formula is expressed as: ； In the formula, is the asphalt adsorption mass of a single particle, The average adsorption performance characterizes the quality of the specimen. It is the mass of single solid waste powder material after incineration.

8. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 7, characterized in that: In step S4, the method for determining the effective area of ​​solid waste powdery material includes: The powdery material is placed in a nitrogen adsorption instrument for low-temperature nitrogen adsorption. The cooling system of the nitrogen adsorption instrument will cool down the sample pool. Nitrogen is passed into the sample pool, and the nitrogen adsorption amount under different nitrogen partial pressures is recorded. The specific surface area of ​​the sample is calculated using the following formula: ； In the formula, V is the volume of gas adsorbed by the powdery material, P is the actual pressure of nitrogen in the adsorption instrument, P0 is the saturated vapor pressure of nitrogen, which is set to 0.1-0.2Pa, and C is the BET constant, which is obtained through linear fitting in the experiment. is the volume of a single molecular layer of nitrogen, ranging from 0.2 to 0.3 cm 3 / g; Then, the nitrogen volume of the monolayer and the BET constant were linearly fitted, and the specific values ​​were obtained through computer graphics to calculate the adsorption specific surface area of ​​the single particle solid waste powder material. The calculation formula is: ； In the formula, is the adsorption specific surface area of ​​a single particle of solid waste powder material, N is Avogadro's constant, A is the surface area of ​​gas molecules, and M is the molar mass of the gas; Then calculate the adsorption amount of solid waste powder asphalt, the calculation formula is expressed as: ； In the formula, is the asphalt adsorption capacity of a single particle of solid waste powder, in mg / mm 2 .

9. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 8, characterized in that: In step S4, the step of calculating the adsorption parameters to evaluate the adsorption performance of the solid waste powdery material to asphalt includes: The particles of different sizes were rearranged in order from large to small according to the asphalt adsorption capacity; Define the particle number in each collector (4) and collection bin (6) as x i , where x is the rearranged particle number; Define the number as x i The asphalt adsorption amount corresponding to the particle is y i , where y is the asphalt adsorption amount; Substituting the data into the coordinate system, a scatter plot of the adsorption amount of granular asphalt of different collectors (4) and collection bins (6) is obtained; Perform a linear fit on each scatter plot and calculate R 2 , when the fitting result is R 2 ≥0.95, the fitting degree is good. 2 When <0.95, the extreme points on the scatter plot of the adsorption of granular asphalt are defined, the extreme points on the scatter plot of the adsorption of granular asphalt are removed, and the linear fitting is re-performed and R is calculated. 2 , repeat the elimination operation until R 2 ≥0.95, the remaining data points are used as the basic data for calculating the asphalt adsorption capacity; Obtaining the asphalt adsorption capacity range of solid waste powder particles of different collectors (4) and collection bins (6); Four asphalt adsorption capacity range data sets are obtained by calculation, and they are arranged from small to large according to the minimum value of each data set, and the four asphalt adsorption capacity range data sets after arrangement are numbered respectively; First, the intersection of the data set numbered as range 1 and the data set numbered as range 2 is taken as set A, and the intersection of the data set numbered as range 3 and the data set numbered as range 4 is taken as set B. The steps for obtaining the average adsorption capacity range of solid waste powder particles include: If both set A and set B are empty, the data sets in range 1 and range 4 are discarded, the data sets in range 2 and range 3 are retained, and the calculation basic data contained in the data sets in range 2 and range 3 are merged to obtain a new data set; If set A is empty and set B is not empty, the data set in range 1 is discarded, the data set in range 2 and set B are retained, and the data set in range 2 and the calculation basic data contained in set B are merged to obtain a new data set; If set B is empty and set A is not empty, the range 4 data set is discarded, and the data sets of set A and range 3 are retained. The data sets of range 3 and the calculation basic data contained in set B are merged to obtain a new data set. If both set A and set B are not empty, then the union of set A and set B is directly taken to merge the basic data to obtain a new data set; For the new data set, the minimum adsorption amount is set equal to the minimum adsorption amount in the calculation base data in the retained data set, and the maximum adsorption amount is set equal to the maximum adsorption amount in the calculation base data in the retained data set, so as to obtain the average adsorption capacity range and median of solid waste powdery particles.

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