A method for evaluating the asphalt adsorption performance of solid waste powdery materials

Abstract

The present invention discloses a method for evaluating the asphalt adsorption performance of solid waste powdery materials, which relates to the technical field of evaluating the adsorption performance of powdery materials on asphalt materials. The method comprises treating the solid waste powdery materials, using a centrifugal separation device to allow the solid waste powdery materials to adsorb asphalt binder dispersed in emulsified asphalt, obtaining a non-agglomerated accumulation state of a test specimen for quantitatively characterizing the asphalt adsorption performance of the powdery materials, preparing a separation state of the test specimen for quantitatively characterizing the asphalt adsorption performance of the powdery materials, screening solid waste powdery particle specimens for asphalt adsorption performance, obtaining the asphalt adsorption mass of a single particle using the solid waste powdery particle specimens, and calculating adsorption parameters to evaluate the asphalt adsorption performance of the solid waste powdery materials. The present invention can quantitatively evaluate the adsorption performance of solid waste powdery materials on asphalt, thereby achieving a quantitative analysis of the adsorption efficiency and degree of interaction between the solid waste powdery materials and the asphalt binder.

Description

Technical Field

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

[0002] Solid waste powder is often used in large quantities as fillers in asphalt pavement materials. However, the interaction between different types of solid waste powder and asphalt directly affects the various properties of asphalt pavement materials. Therefore, evaluating the adsorption properties of solid waste powder on asphalt binder is crucial for clarifying the interaction between the two, providing a basis and guarantee for the excellent 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 the 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, 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 pulverulent materials through physical and chemical treatments may affect the adsorption capacity of the pulverulent materials themselves, resulting in a large deviation between the adsorption capacity and actual performance. Third, the existing research on the characterization parameters of adsorption performance is not accurate enough, and the evaluation methods are relatively simple, which cannot fully evaluate the adsorption performance of solid waste pulverulent materials on asphalt materials. Therefore, there is an urgent need to propose a reasonable and effective evaluation method for the adsorption performance of solid waste pulverulent materials on asphalt, so as to provide relevant scientific basis and technical support for improving the resource utilization of solid waste pulverulent materials in asphalt pavement materials. Summary of the Invention

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

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] 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:

[0007] S1. Processing solid waste powdery materials, using a centrifugal separation device to allow the solid waste powdery materials to absorb the asphalt binder dispersed in the emulsified asphalt, and obtaining a non-agglomerated accumulation state of a test piece for characterizing the asphalt adsorption performance of the powdery materials;

[0008] S2. Start the centrifugal separation device to centrifuge the non-agglomerated, accumulated powdery material specimens for characterizing and quantifying asphalt adsorption performance. Under the action of centrifugal force, the specimens are separated into collectors at different heights. At the same time, large asphalt-powder particles settle into the collection chamber at the bottom of the centrifugal separation device under the action of gravity. Solid waste powdery particles with different asphalt adsorption amounts are collected to prepare the separation state of the powdery material specimens for characterizing and quantifying asphalt adsorption performance.

[0009] S3. Based on the particle size composition of the separation state of the quantified specimens of the asphalt adsorption performance of the powdery material, the separation state of the quantified specimens of the asphalt adsorption performance of the powdery material with different particle size compositions is quantitatively calculated to screen the solid waste powdery particle specimens with the best asphalt adsorption performance;

[0010] S4. Obtain the asphalt adsorption mass of a single particle through solid waste powdery particle specimens, calculate the effective adsorption area of ​​the solid waste powdery material using the BET specific surface area calculation method, and calculate the adsorption parameters to evaluate the adsorption performance of the solid waste powdery material on asphalt.

[0011] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials according to the present invention, in step S1, the centrifugal separation device includes a rotary power device, a container disposed on the top of the rotary power device, and a collection bin disposed at the bottom of the container;

[0012] A group of stirring rods are fixedly connected to the top of the collecting bin in a circumferential manner, the inner side wall of the container is provided with an asphalt height scale line, collectors are provided on both sides of the outside of the container, and each connection part between the collector and the container is provided with a one-way filter screen, and the bottom ends of both sides of the container are provided with storage bins, and the connection ends of the storage bins are connected to air ducts for introducing compressed air, and 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 provided at the top of the container.

[0013] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powder materials of the present invention, in step S1, the solid waste powder materials to be processed include fly ash from garbage incineration, slag powder and fly ash, with a particle size range of 4-45 μm and a density range of 1.0-3.0 g / cm 3 ;

[0014] 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 washing multiple times, placing the solid waste powdery materials in an oven at 160°C for drying for 40-60 minutes after washing, taking out the powdery materials after drying, and evenly spreading them on a cleaned sieve plate with a sieve hole size of 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.

[0015] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials according to the present invention, wherein: in the step S1, a centrifugal separation device is used to make the powdery material adsorb 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 300-500 ml, using a baffle to cover the collector inlet on the inner wall of the device, and dividing 100-150 g of the screened solid waste powdery material into the storage bins at both ends respectively, and spraying compressed air into the storage bin to drive the solid waste powdery material into the container filled with emulsified asphalt, and simultaneously starting the rotary power device at the bottom of the device to rotate the stirring rod, and then causing the powdery material to adsorb the asphalt binder dispersed in the emulsified asphalt, setting the total adsorption time to 20-30 minutes, and obtaining the non-agglomerated accumulation state of the quantitative test specimen for characterizing the asphalt adsorption performance of the powdery material;

[0016] Among them, the rotation power equipment is set to be turned on for 10 minutes, the injection flow rate of compressed air is set to 20-30 L / min, and the injection time is set to 5 minutes.

[0017] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials of the present invention, the step of preparing the separation state of the powdery material asphalt adsorption performance characterization test piece in step S2 includes:

[0018] Start the centrifugal function of the centrifugal separation device, set the speed of the centrifugal separation device to 6000-8000rpm, and the time to 10-15 minutes. Due to the difference in mass of the powdery material particles with different asphalt adsorption amounts, the particles are separated into collectors at different heights under the action of centrifugal force. At the same time, the large particles of asphalt-silty particles will settle to the collection bin at the bottom under the action of gravity;

[0019] After the centrifugation time is reached, stop the centrifugal separation device and place the asphalt-silt particles in the collection bin into different clean containers. Pour the asphalt-silt particles obtained from different collectors into the shaker, evenly pour 50ml of 0.1% sodium octyl polyoxyethylene ether sulfate surfactant, and start the shaker. Set the shaking time to 3-5 minutes to fully mix the surfactant with the particles.

[0020] After the shaking is completed, the mixture in the shaker is evenly poured onto the organic microfiltration membrane to filter and separate the active agent and the asphalt adsorption characterization particles, wherein 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.

[0021] 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 for characterizing the asphalt adsorption performance of different powdery materials includes:

[0022] Solid waste powder particles with extreme particle sizes are eliminated, and the separation state of the powdery 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 powdery material asphalt adsorption performance characterization and quantification test pieces in the collector and the collection bin is obtained, the extreme particle size is defined, and the particle size mean μ and standard deviation σ of the solid waste adsorption particles are calculated. The extreme particle size is defined as: the normal particle size range is expressed as [μ-2σ, μ+2σ], and the particle size value outside this particle size range is defined as the extreme particle size;

[0023] The separation of the powdery material asphalt adsorption performance characterization quantification test piece was 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 ;

[0024] Where i is the number corresponding to multiple collectors and a collection bin, and j is the number of the particle involved in the counting.

[0025] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials according to the present invention, in step S4, the calculation method for evaluating the adsorption performance of solid waste powdery materials on asphalt by using adsorption parameters includes:

[0026] 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 60-90 minutes. After cooling, they were 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:

[0027] ;

[0028] Where, is the asphalt adsorption mass of a single particle, The average adsorption performance characterizes the quality of the specimen, It is the mass of a single solid waste powder material after incineration.

[0029] As a preferred embodiment of the method for evaluating the asphalt adsorption performance of solid waste powdery materials according to the present invention, in step S4, the step of calculating the adsorption parameter to evaluate the asphalt adsorption performance of the solid waste powdery materials includes:

[0030] Rearrange the particles of different sizes in descending order of asphalt adsorption capacity;

[0031] Define the particle number in each collector and collection bin as x i , where x is the rearranged particle number;

[0032] Define the number as x i The asphalt adsorption amount corresponding to the particle is y i , where y is the asphalt adsorption amount;

[0033] Substitute the data into the coordinate system to obtain the scatter plot of the adsorption amount of granular asphalt of different collectors and collection bins;

[0034] Perform a linear fit on each scatter plot and calculate R 2 , when the fitting result R 2 ≥0.95, the fitting degree is good. 2 When the value is less than 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 to calculate R 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;

[0035] Obtain the range of asphalt adsorption capacity of solid waste powder particles in different collectors and collection bins;

[0036] Four asphalt adsorption capacity range data sets were obtained by calculation, and they were arranged from small to large according to the minimum value of each data set. The four arranged asphalt adsorption capacity range data sets were numbered respectively.

[0037] First, the intersection of the data set numbered range 1 and the data set numbered range 2 is taken as set A, and the intersection of the data set numbered range 3 and the data set numbered range 4 is taken as set B. The steps for obtaining the average adsorption capacity range of solid waste powder particles include:

[0038] If both Set A and Set B are empty, the datasets in range 1 and range 4 are discarded, the datasets in range 2 and range 3 are retained, and the calculation basic data contained in the datasets in range 2 and range 3 are merged to obtain a new dataset;

[0039] If set A is empty and set B is not empty, the dataset in range 1 is discarded, the dataset in range 2 and set B are retained, and the calculation basic data contained in the dataset in range 2 and set B are merged to obtain a new dataset;

[0040] If set B is empty and set A is not empty, then the range 4 dataset is discarded, and set A and the range 3 dataset are retained. The range 3 dataset and the calculation basic data contained in set B are merged to obtain a new dataset.

[0041] 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;

[0042] For the new data set, the minimum adsorption capacity is set equal to the minimum adsorption capacity in the calculation base data in the retained data set, and the maximum adsorption capacity is set equal to the maximum adsorption capacity in the calculation base data in the retained data set to obtain the average adsorption capacity range and median of solid waste powdery particles.

[0043] The beneficial effects of the present invention are: more accurate and scientific quantitative evaluation and analysis of the asphalt adsorption performance of solid waste powder materials at the powder 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, taking into account the influencing factors of various indicators, and providing 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

[0044] 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. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0045] Figure 1 Flowchart of the method for evaluating the asphalt adsorption performance of solid waste powdery materials.

[0046] Figure 2 This is a structural diagram of a centrifugal separation device.

[0047] 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.

[0048] Figure 4 Schematic diagram of asphalt adsorption quality of characterizing specimens for the evaluation method of asphalt adsorption performance of solid waste powdery materials.

[0049] 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.

[0050] 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

[0051] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0052] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. 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.

[0053] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0054] The present invention is described in detail with reference to schematic diagrams. For ease of illustration, cross-sectional views of device structures may be partially enlarged and not to scale when describing embodiments of the present invention. Furthermore, the schematic diagrams are merely illustrative and should not limit the scope of the present invention. Furthermore, in actual production, the three-dimensional dimensions of length, width, and depth should be included.

[0055] In the description of the present invention, it should be noted that the terms "upper, lower, inner, and outer" and other references to orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first, second, or third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0056] In this disclosure, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they may refer to fixed, removable, or integral connections. They may also refer to mechanical, electrical, or direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this disclosure.

[0057] Example 1

[0058] First of all, it should be noted that the powder sample used in this example comes from the fly ash incinerated by the grate furnace of a waste incineration plant in Zhongshan. The main incineration material is municipal solid waste. Its particle size range is 4-45 μm, and the density range is 1.0-3.0 g / cm 3 .

[0059] Reference Figures 1 to 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:

[0060] S1. Process 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 quantitatively characterize the asphalt adsorption performance of the powdery materials.

[0061] The method for treating solid waste powdery materials includes: weighing 100-150 g of solid waste powdery materials, adding distilled water to the solid waste powdery materials for multiple washing, placing the solid waste powdery materials in an oven at 160° C. for drying for 40-60 minutes after washing, taking out the powdery materials after drying, and spreading them evenly on a cleaned sieve plate with a sieve hole size of 325 mesh (45 μm), using a vibrating sieve machine to vibrate and screen the powdery materials, and taking out the sieved solid waste powdery materials after screening.

[0062] The centrifugal separation device includes a rotary power device 1, a container 11 arranged on the top of the rotary power device 1, and a collection bin 6 arranged at the bottom of the container 11;

[0063] A group of stirring rods 2 are circumferentially fixed to the top of the collecting bin 6, an asphalt height scale line 3 is provided on the inner wall of the material container 11, collectors 4 are provided on both sides of the outside of the material container 11, and each connection part 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. The connecting ends of the storage bins 7 are connected to air ducts 10, which are used to introduce compressed air. A compressed air control air pressure valve 8 is installed on 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.

[0064] 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 adsorbing the asphalt binder by the solid waste powdery material and centrifugally classifying and adsorbing 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 in Highway Engineering", the demulsification time is 6-8 minutes.

[0065] 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. A baffle is used to cover the entrance of the collector 4 on the inner wall of the device. The 100~150g solid waste powdery material after screening is evenly divided and placed in the storage bins 7 at both ends respectively. 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 prompted to absorb the asphalt binder dispersed in the emulsified asphalt. The total adsorption time is set to 20~30min, and the non-agglomerated accumulation state of the powdery material asphalt adsorption performance characterization quantitative specimen is obtained;

[0066] 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 20-30 L / min, and the injection time is set to 5 minutes.

[0067] S2. Start the centrifugal separation device to centrifuge the non-agglomerated accumulated powdery material asphalt adsorption performance characterization and quantification test piece, and separate it into collectors 4 at different heights under the action of centrifugal force. At the same time, large particles of asphalt-powdery particles will settle into the collection bin 6 at the bottom of the centrifugal separation device under the action of gravity, and collect solid waste powdery particles with different asphalt adsorption amounts to prepare the separation state of the powdery material asphalt adsorption performance characterization and quantification test piece.

[0068] In step S2, the steps of preparing a test piece for characterizing the performance of asphalt adsorption include:

[0069] Start the centrifugal function of the centrifugal separation device, set the speed of the centrifugal separation device to 6000-8000 rpm, and the time to 10-15 minutes. In this embodiment, the speed is set to 6000 rpm and the time is set to 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 chamber 6 at the bottom of the instrument under the action of gravity;

[0070] After the centrifugation time is reached, the centrifugal separation device is stopped, and the asphalt-silt particles in the collection chamber 6 are placed in different clean containers respectively. The asphalt-silt particles obtained from different collectors 4 are poured into the oscillator respectively, and 50 ml of 0.1% by mass fraction of sodium octyl polyoxyethylene ether sulfate surfactant is evenly poured into it. The oscillator is started and the oscillation time is set to 3 to 5 minutes. In this embodiment, the time is 4 minutes to fully mix the surfactant with the particles.

[0071] After the shaking is completed, the mixture in the shaker is evenly poured onto the organic microfiltration membrane to filter and separate the active agent and the asphalt adsorption characterization particles, wherein 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.

[0072] S3. Based on the particle size composition of the separation state of the quantitative specimens of the asphalt adsorption performance characterization of powdery materials, the separation state of the quantitative specimens of the asphalt adsorption performance characterization of powdery materials with different particle size compositions is quantitatively calculated to screen the solid waste powdery particle specimens with good asphalt adsorption performance.

[0073] In step S3, the particle size composition analysis method of different solid waste powder particles includes:

[0074] 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, first, 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 to perform 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 outside this particle size range is defined as the extreme particle size;

[0075] The separation of the test piece of powdery material asphalt adsorption performance characterization and quantification was flattened and photographed with a camera. The image was imported into MATLAB software and the imbinarize function was used to perform image binarization processing. The image processing tool (Image Processing Toolbox) provided by MATLAB was used to count the particles in the binarized image to obtain the number of particles of different particle sizes. ;

[0076] After removing particles with extreme particle sizes, i.e. particles with a particle size range outside [μ-2σ, μ+2σ], each collector 4 and collection bin 6 can obtain an average adsorption performance characterization specimen, wherein the final removal results are shown in Table 1;

[0077] Table 1: Average adsorption performance characterization specimen calculation table

[0078]

[0079] After counting, the average adsorption performance characterization specimens were weighed one by one, and a high-precision electronic balance with a sensitivity of 0.01 mg was used to weigh the particles to obtain the mass of each average adsorption performance characterization specimen. ;

[0080] Here, i is the number corresponding to the multiple collectors 4 and one collection bin 6, and j is the number of the particle involved in the counting.

[0081] S4. Obtain the asphalt adsorption mass of a single particle through solid waste powdery particle specimens, calculate the effective adsorption area of ​​the solid waste powdery material using the BET specific surface area calculation method, and calculate the adsorption parameters to evaluate the adsorption performance of the solid waste powdery material on asphalt.

[0082] In step S4, the calculation method for evaluating the adsorption performance of solid waste powdery materials to asphalt using adsorption parameters includes:

[0083] The average adsorption performance characterization specimens collected in different collectors 4 and collection bins 6 are placed into 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:

[0084] ;

[0085] Where, 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;

[0086] In this embodiment, refer to Figure 4 As shown, the black collector corresponds to the line segment 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 attached Figure 2 The collector 4 is located in the second layer; Figure 4 The line segment corresponding to the blue collector is the attached Figure 2 The collector 4 is located on the third layer.

[0087] Methods for determining the effective area of ​​solid waste powdery materials include:

[0088] The effective adsorption area of ​​the powdery material was determined using the Brenner-Emmert-Taylor method (BET specific surface area). Nitrogen was selected as the adsorption gas, and a nitrogen adsorption instrument was used. 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 cooled the sample cell to -196°C. Nitrogen was introduced into the sample cell, where it was adsorbed onto the sample surface. The nitrogen adsorption amount at different nitrogen partial pressures was recorded. The adsorption and desorption processes were performed at 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 data accuracy and calculate the specific surface area of ​​the sample.

[0089] Then, a linear fit is performed on the nitrogen volume of the monolayer and the BET constant, and the specific value is obtained through computer mapping to calculate the effective adsorption area of ​​a single solid waste powder material;

[0090] In this embodiment, refer to Figure 5 As shown, the black collector corresponds to the line segment 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 attached Figure 2 The collector 4 is located in the second layer; Figure 5 The line segment corresponding to the blue collector is the attached Figure 2 The collector 4 is located on the third layer.

[0091] Then calculate the asphalt adsorption capacity of solid waste powdery materials, the calculation formula is expressed as:

[0092] ;

[0093] Where, Asphalt adsorption capacity of single particle solid waste powder material, unit is mg / mm 2 .

[0094] The steps for calculating adsorption parameters to evaluate the adsorption performance of solid waste powder materials to asphalt include:

[0095] Rearrange the particles of different sizes in descending order of asphalt adsorption capacity;

[0096] Define the particle number in each collector 4 and collection bin 6 as x i , where x is the rearranged particle number;

[0097] Define the number as x i The asphalt adsorption amount corresponding to the particle is y i , where y is the asphalt adsorption amount;

[0098] Substitute the data into the coordinate system to obtain the scatter plot of the adsorption amount of granular asphalt of different collectors 4 and collection bins 6;

[0099] Perform a linear fit on each scatter plot and calculate R 2 , when the fitting result R 2 ≥0.95, the fitting degree is good. 2 When the value is less than 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 to calculate R 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 , the y values ​​that are not in this range are defined as the extreme points on the scatter plot. The basic data results table for the calculation of asphalt adsorption capacity are shown in Table 2;

[0100] Table 2: Detailed data for calculating asphalt adsorption capacity

[0101]

[0102] Obtaining the asphalt adsorption capacity range of solid waste powder particles in different collectors 4 and collection bins 6, specifically comprising the following steps: for the same collector 4 or collection bin 6, setting the minimum adsorption capacity equal to the minimum adsorption capacity in the basic data calculated for the collector 4 or collection bin 6, and setting the maximum adsorption capacity equal to the maximum adsorption capacity in the basic data calculated for the collector 4 or collection bin 6, thereby obtaining the asphalt adsorption capacity range of solid waste powder particles in the collector 4 or collection bin 6;

[0103] 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, among which 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;

[0104] First, the intersection of the data set numbered range 1 and the data set numbered range 2 is taken as set A, and the intersection of the data set numbered range 3 and the data set numbered range 4 is taken as set B. The steps for obtaining the average adsorption capacity range of solid waste powder particles include:

[0105] If both Set A and Set B are empty, the datasets in range 1 and range 4 are discarded, the datasets in range 2 and range 3 are retained, and the calculation basic data contained in the datasets in range 2 and range 3 are merged to obtain a new dataset;

[0106] If set A is empty and set B is not empty, the dataset in range 1 is discarded, the dataset in range 2 and set B are retained, and the calculation basic data contained in the dataset in range 2 and set B are merged to obtain a new dataset;

[0107] If set B is empty and set A is not empty, then the range 4 dataset is discarded, and set A and the range 3 dataset are retained. The range 3 dataset and the calculation basic data contained in set B are merged to obtain a new dataset.

[0108] 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;

[0109] For example, refer to Figure 3 and Figure 6 As shown, Figure 3 Schematic 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 asphalt adsorption capacity of solid waste powdery materials in the whole device, Figure 6 It can be seen that set A is an empty set, excluding the range [1.48, 2.51]. The data set of range 3 ∩ the data set of range 4 = set B, that is, set B = [64.96, 71.73]. If the rule that set A is empty and B is not empty is met, then 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].

[0110] For the new data set, the minimum adsorption capacity is set to be equal to the minimum adsorption capacity in the calculation base data in the retained data set, and the maximum adsorption capacity is set to be equal to the maximum adsorption capacity in the calculation base data in the retained data set, and the average adsorption capacity range and median of solid waste powder particles are obtained;

[0111] In this example, the median value is calculated as (23.47 + 71.73) / 2 = 47.6, that is, the median value = 47.6 mg / mm 2 .

[0112] In summary, the performance of solid waste powder materials in adsorbing asphalt is more accurately and scientifically evaluated and analyzed quantitatively at the powder 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 taken into account to evaluate the adsorption performance of solid waste materials on asphalt materials and provide a scientific basis for the practicality, economy and accuracy of the selection of asphalt mixture fillers in actual production.

[0113] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. 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 may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, and all of these should 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. Processing solid waste powdery materials, using a centrifugal separation device to allow the solid waste powdery materials to absorb the asphalt binder dispersed in the emulsified asphalt, and obtaining a non-agglomerated accumulation state of a test piece for characterizing the asphalt adsorption performance of the powdery materials; S2. Start the centrifugal separation device to centrifuge the non-agglomerated powdery material asphalt adsorption performance characterization and quantification test piece, and separate it into collectors (4) 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 (6) at the bottom of the centrifugal separation device under the action of gravity, and collect solid waste powdery particles with different asphalt adsorption amounts to prepare the separation state of the powdery material asphalt adsorption performance characterization and quantification test piece; S3. Based on the particle size composition of the separated powdery material asphalt adsorption performance characterization and quantification test pieces, the number and quality of the separated powdery material asphalt adsorption performance characterization and quantification test pieces with different particle size compositions are calculated to screen solid waste powdery particle test pieces with good asphalt adsorption performance; S4. Eliminate the extreme particle size of the solid waste powder particle specimen to obtain an average adsorption performance characterization specimen, and calculate the asphalt adsorption mass of a single particle by burning the average adsorption performance characterization specimen. ; Then the effective adsorption area of ​​a single solid waste powder material after incineration is calculated by the BET specific surface area calculation method , and then the asphalt adsorption mass of the single particle and the effective adsorption area of ​​the single solid waste powder material Calculate the asphalt adsorption capacity of single particle solid waste powder material Finally, the adsorption parameters are obtained by the asphalt adsorption amount of single-particle solid waste powdery materials, and the adsorption performance of solid waste powdery materials on asphalt is evaluated by the adsorption parameters, wherein the adsorption parameters are the average adsorption capacity range and median value of solid waste powdery materials; The calculation formula for the asphalt adsorption capacity of single-particle solid waste powdery material is expressed as follows: ； Where, is the asphalt adsorption capacity of a single particle of solid waste powdery material, is the asphalt adsorption mass, It is the effective adsorption area of ​​a single solid waste powder material.

2. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 1, wherein: In step S1, the centrifugal separation device includes a rotary power device (1), a container (11) arranged on 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 an asphalt height scale line (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 to air guide pipes (10). The air guide pipes (10) are used to introduce compressed air. A compressed air control air pressure valve (8) is installed at the end of the air guide pipe (10) away from the container (11). A group of pressure relief holes (9) are opened 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, wherein: In step S1, the method for processing solid waste powdery material includes: weighing 100-150g of solid waste powdery material, adding distilled water to the solid waste powdery material for multiple washing, placing the solid waste powdery material in an oven at 160°C for drying for 40-60 minutes after washing, taking out the powdery material after drying, and evenly spreading it on a cleaned sieve plate with a sieve hole size of 325 mesh, using a vibrating sieve shaker to vibrate and screen the powdery material, and taking out the sieved solid waste powdery material after screening.

4. The method for evaluating the asphalt adsorption performance of solid waste powdery materials according to claim 3, wherein: In the step S1, a centrifugal separation device is used to allow the powdery material to absorb the asphalt binder dispersed in the emulsified asphalt. The specific steps include: weighing the emulsified asphalt and placing it in a beaker, 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 300-500 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 screened solid The solid waste powdery materials are evenly divided and placed in the storage bins (7) at both ends respectively. Compressed air is sprayed into the storage bins (7). The compressed air drives the solid waste powdery materials into the container (11) filled with emulsified asphalt, and the rotary power device (1) at the bottom of the device is simultaneously turned on to rotate the stirring rod (2). The powdery materials are then prompted to absorb the asphalt binder dispersed in the emulsified asphalt. The total adsorption time is set to 20 to 30 minutes to obtain the non-agglomerated accumulation state of the asphalt adsorption performance characterization quantitative specimen of the powdery materials. The rotational power device (1) is turned on for 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, wherein: In step S2, the step of preparing the separation state of the powdery material asphalt adsorption performance characterization quantitative test piece includes: Start the centrifugal function of the centrifugal separation device, set the speed of the centrifugal separation device to 6000-8000 rpm, set the time to 10-15 minutes, and measure the difference in the quality of the powdery material particles with different asphalt adsorption amounts; After the centrifugation time is reached, the centrifugal separation device is stopped, and the asphalt-silt particles in the collection chamber (6) are placed in different clean containers, and the asphalt-silt particles obtained from different collectors (4) are poured into the shaker, and 50 ml of 0.1% by mass octyl polyoxyethylene ether sodium sulfate surfactant is evenly poured into it, and the shaker is started, and the shaking time is set to 3 to 5 minutes to fully mix the surfactant with the particles; After the shaking is completed, the mixture in the shaker is evenly poured onto the organic microfiltration membrane to filter and separate the active agent and the asphalt adsorption characterization particles, wherein 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, wherein: In step S3, the particle size composition analysis method for characterizing the quantification of the adsorption performance of asphalt of different powdery materials includes: The solid waste powder particles with extreme particle size are eliminated, and the separation state of the powder material asphalt adsorption performance characterization and quantification test piece is analyzed by using a laser particle size analyzer, 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 outside this particle size range is defined as the extreme particle size; The separation of the powdery material asphalt adsorption performance characterization quantification test piece was 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, wherein: In step S4, the calculation method for evaluating the adsorption performance of solid waste powdery materials to asphalt using adsorption parameters includes: The average adsorption performance characterization test pieces collected from different collectors (4) and collection bins (6) were placed into a furnace one by one and incinerated at 700°C for 60 to 90 minutes, and then cooled. After that, they were 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: ； Where, is the asphalt adsorption mass of a single particle, The average adsorption performance characterizes the quality of the specimen, It is the mass of a 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, wherein: In step S4, the step of calculating the adsorption parameters to evaluate the adsorption performance of the solid waste powdery material on asphalt includes: Rearrange the particles of different sizes in descending order of 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 adsorption amount of granular asphalt of different collectors (4) and collection bins (6); Perform a linear fit on each scatter plot and calculate R 2 , when the fitting result R 2 ≥0.95, the fitting degree is good. 2 When the value is less than 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 to calculate R 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 in different collectors (4) and collection bins (6); Four asphalt adsorption capacity range data sets were obtained by calculation, and they were arranged from small to large according to the minimum value of each data set. The four arranged asphalt adsorption capacity range data sets were numbered respectively. First, the intersection of the data set numbered range 1 and the data set numbered range 2 is taken as set A, and the intersection of the data set numbered range 3 and the data set numbered 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 datasets in range 1 and range 4 are discarded, the datasets in range 2 and range 3 are retained, and the calculation basic data contained in the datasets in range 2 and range 3 are merged to obtain a new dataset; If set A is empty and set B is not empty, the dataset in range 1 is discarded, the dataset in range 2 and set B are retained, and the calculation basic data contained in the dataset in range 2 and set B are merged to obtain a new dataset; If set B is empty and set A is not empty, then the range 4 dataset is discarded, and set A and the range 3 dataset are retained. The range 3 dataset and the calculation basic data contained in set B are merged to obtain a new dataset. 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 capacity is set equal to the minimum adsorption capacity in the calculation base data in the retained data set, and the maximum adsorption capacity is set equal to the maximum adsorption capacity in the calculation base data in the retained data set to obtain the average adsorption capacity range and median of solid waste powdery materials.

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