阅读说明：本技术 一种厂拌冷再生系统的控制方法 (Control method of plant-mixed cold regeneration system ) 是由 周敏 吴超凡 曾国东 李泉 常荣华 韩庆奎 李珏池 何禹忠 于 2020-03-25 设计创作，主要内容包括：本发明公开了一种厂拌冷再生系统的控制方法,其包括根据理论设计比例进行第一矿料级配合成,测定实际生产过程中的第二矿料级配；并对第一矿料级配和第二矿料级配比较,测定级配的准确度；并根据上述级配准确度对生产系统中的破碎单元、筛分单元、称量单元进行调节。本发明的控制方法,可根据级配准确度快速调控生产系统,提升了控制准确度,提升了厂拌冷再生乳化沥青混合料的均一性和综合性能。(The invention discloses a control method of a plant mixing cold regeneration system, which comprises the steps of carrying out first mineral aggregate gradation synthesis according to a theoretical design proportion, and measuring second mineral aggregate gradation in the actual production process; comparing the first mineral aggregate gradation with the second mineral aggregate gradation to determine the accuracy of the gradation; and adjusting the crushing unit, the screening unit and the weighing unit in the production system according to the grading accuracy. The control method can quickly regulate and control the production system according to the grading accuracy, improves the control accuracy, and improves the uniformity and the comprehensive performance of the plant-mixed cold-recycling emulsified asphalt mixture.)

1. The control method of the plant mixing cold regeneration system is characterized in that the plant mixing cold regeneration system comprises a crushing unit, a screening unit, a weighing unit and a mixing unit;

the crushing unit and the screening unit are used for treating the waste asphalt mixture;

the weighing unit comprises a first weighing unit for weighing the new aggregate; the second weighing unit is used for weighing the waste asphalt mixture and the third weighing unit is used for weighing the mineral powder;

the control method of the plant-mixed cold regeneration system comprises the following steps:

(1) determining the mixing proportion of the waste asphalt mixture, the new aggregate, the mineral powder and the emulsified asphalt in the plant-mixed cold-recycling emulsified asphalt mixture;

(2) carrying out gradation synthesis according to the mixing proportion, and determining the first mineral aggregate gradation of the plant-mixed cold-recycling emulsified asphalt mixture;

(3) taking the plant-mixed cold-recycling emulsified asphalt mixture produced actually, extracting and screening to determine the second mineral aggregate gradation of the recycling mixture;

(4) calculating the accuracy of the grading according to the following formula group; the accuracy includes A, A₁、A₂And A₃；

Wherein, X_iGrading the first mineral aggregate of the ith grade mineral aggregate; y is_iThe grade is the second mineral aggregate grade of the ith grade cold-recycling mixture, and N is the sample number;

(5) if A is larger than or equal to 2, correcting the crushing unit and the screening unit;

if A is not less than 1.5 and less than 2 and A₃Correcting the crushing unit and the screening unit if the number is more than or equal to 2.5;

if A is more than or equal to 1.5 and less than 2 and A is more than 1.5₃< 2.5, and A₂If the weight is less than or equal to 1.5, correcting the first weighing unit;

if A is more than or equal to 1.5 and less than 2 and A is more than 1.5₃< 2.5, and 1.5 < A₂If the number is less than 2, correcting the first weighing unit and the second weighing unit;

if A is more than or equal to 1.5 and less than 2, A₃Less than or equal to 1.5, and A₂Correcting the second weighing unit if the weighing capacity is more than or equal to 2;

if A is more than or equal to 0.8 and less than 1.5, A₁If the value is less than 1, correcting the second weighing unit;

if A is more than or equal to 0.8 and less than 1.5, A₁Not less than 1, and A₂If the value is less than 1.5, correcting the third weighing unit;

if A is less than 0.6, the system works normally.

2. The method of claim 1, wherein in step (1), the formulation is performed according to annex F of JTG 5521-2019.

3. The control method of the plant-mixed cold recycling system according to claim 1, wherein in the step (1), the first particle size distribution of the waste asphalt mixture is adopted for proportioning design;

the first particle composition is obtained by directly screening the waste asphalt mixture after drying and crushing.

4. The control method of the plant-mixed cold recycling system according to claim 3, wherein the first particle composition and the second particle composition of the waste asphalt mixture are adopted for proportioning design;

the second particle grading is the grading obtained after the extraction and screening of the waste asphalt mixture.

5. The method of controlling a plant cold regeneration system according to claim 1, wherein the step (2) comprises:

(2.1) extracting and screening the waste asphalt mixture to obtain a second particle size distribution;

and (2.2) carrying out grading synthesis according to the proportion in the step (1) to obtain a first mineral aggregate grading.

6. The method of claim 4, wherein the first mineral composition, the second mineral composition, the first particle composition, and the second particle composition are screened using a standard set of screens having a pore size of 31.5mm, 26.5mm, 19mm, 16mm, 13.2mm, 9.5mm, 4.75mm, 2.36mm, 1.18mm, 0.6mm, 0.3mm, 0.15mm, 0.075 mm.

7. The control method of the plant-mixed cold recycling system of claim 1, wherein the first grain composition of the waste asphalt mixture is 85-90% of a 19mm pass rate.

Technical Field

The invention relates to the technical field of plant-mixed cold regeneration, in particular to a control method of a plant-mixed cold regeneration system.

Background

The cold-recycling emulsified asphalt mixture is prepared by mixing waste asphalt pavement material (RAP) with new aggregate, mineral powder (such as cement, limestone powder and the like) and emulsified asphalt; then mixing the mixture at normal temperature to obtain a mixture. After the proportioning design is finished, the continuous production is directly carried out. In the production process, the quality control is carried out through a cleavage test (JTG E20-2011), however, the cleavage test can be completed in 2-3 days. When a problem occurs in a production system, it is often difficult to quickly and accurately obtain a reflection. For example, when a weighing system of some raw materials fails (weighing is inaccurate), the mixture formula is changed, the mineral aggregate gradation is changed, and the performance of the cold-recycling emulsified asphalt mixture is changed, but the existing detection means cannot reflect the problem in time, so that the control of the production system is delayed.

In order to maintain the performance of the cold-recycling emulsified asphalt mixture as much as possible, the conventional method is to design a wider proportioning range and a grading range as much as possible. However, this approach often results in large and difficult to control fluctuations in the properties of the same batch at the same design scale. Therefore, it is an urgent technical problem in the art to find a system capable of rapidly detecting the related properties of the mixture to achieve rapid feedback and control of cold recycling of the plant mix.

On the other hand, in the existing specifications (JTG5521-2019 and the like), the proportion and gradation synthesis experiment is generally carried out by directly adopting RAP gradation (namely, gradation when the waste asphalt mixture is not subjected to asphalt removal); after the experiment is completed and the production stage is started, due to the existence of old asphalt, emulsified asphalt, water and the like in the emulsified asphalt plant-mixed cold-recycling asphalt mixture, the grading condition of the mixture cannot be detected, and the good detection of the quality of the mixture cannot be realized through grading comparison. Thus, in the general knowledge of those skilled in the art, the quality of the mix is not controlled by gradation comparison.

Disclosure of Invention

The technical problem to be solved by the invention is that the invention provides a plant-mixed cold regeneration system control method, which can realize the quick detection of the plant-mixed cold regeneration system and further realize the quick feedback control of a production system; the homogeneity of the same batch is ensured, and the overall performance of the cold-mix plant mixture is improved.

In order to solve the technical problem, the invention provides a control method of a plant mixing cold regeneration system, wherein the plant mixing cold regeneration system comprises a crushing unit, a screening unit, a weighing unit and a mixing unit;

the crushing unit and the screening unit are used for treating the waste asphalt mixture;

the weighing unit comprises a first weighing unit for weighing the new aggregate; the second weighing unit is used for weighing the waste asphalt mixture and the third weighing unit is used for weighing the mineral powder;

the control method of the plant-mixed cold regeneration system comprises the following steps:

(1) determining the mixing proportion of the waste asphalt mixture, the new aggregate, the mineral powder and the emulsified asphalt in the plant-mixed cold-recycling emulsified asphalt mixture;

(2) carrying out gradation synthesis according to the mixing proportion, and determining the first mineral aggregate gradation of the plant-mixed cold-recycling emulsified asphalt mixture;

(3) taking the plant-mixed cold-recycling emulsified asphalt mixture produced actually, extracting and screening to determine the second mineral aggregate gradation of the recycling mixture;

(4) calculating the accuracy of the grading according to the following formula group; the accuracy packageScraper A, A₁、A₂And A₃；

Wherein, X_iGrading the first mineral aggregate of the ith grade mineral aggregate; y is_iGrading a second mineral aggregate of the ith grade cold-recycling mixture; n is the number of samples.

(5) If A is larger than or equal to 2, correcting the crushing unit and the screening unit;

if A is not less than 1.5 and less than 2 and A₃Correcting the crushing unit and the screening unit if the number is more than or equal to 2.5;

if A is more than or equal to 1.5 and less than 2 and A is more than 1.5₃< 2.5, and A₂If the weight is less than or equal to 1.5, correcting the first weighing unit;

if A is more than or equal to 1.5 and less than 2 and A is more than 1.5₃< 2.5, and 1.5 < A₂If the number is less than 2, correcting the first weighing unit and the second weighing unit;

if A is more than or equal to 1.5 and less than 2, A₃Less than or equal to 1.5, and A₂Correcting the second weighing unit if the weighing capacity is more than or equal to 2;

if A is more than or equal to 0.8 and less than 1.5, A₁If the value is less than 1, correcting the second weighing unit;

if A is more than or equal to 0.8 and less than 1.5, A₁Not less than 1, and A₂If the value is less than 1.5, correcting the third weighing unit;

if A is less than 0.6, the system works normally.

As an improvement of the technical scheme, in the step (1), the proportioning design is carried out by adopting a method in annex F of JTG 5521-2019.

As an improvement of the technical scheme, in the step (1), the first particle size distribution of the waste asphalt mixture is adopted for proportioning design;

the first particle composition is obtained by directly screening the waste asphalt mixture after drying and crushing.

As an improvement of the technical scheme, the first particle composition and the second particle composition of the waste asphalt mixture are adopted for carrying out proportioning design;

the second particle grading is the grading obtained after the extraction and screening of the waste asphalt mixture.

As an improvement of the technical scheme, the step (2) comprises the following steps:

(2.1) extracting and screening the waste asphalt mixture to obtain a second particle size distribution;

and (2.2) carrying out grading synthesis according to the proportion in the step (1) to obtain a first mineral aggregate grading.

As an improvement of the technical scheme, when the first mineral aggregate gradation, the second mineral aggregate gradation, the first particle gradation and the second particle gradation are measured, standard set sieves with the pore diameter of 31.5mm, 26.5mm, 19mm, 16mm, 13.2mm, 9.5mm, 4.75mm, 2.36mm, 1.18mm, 0.6mm, 0.3mm, 0.15mm and 0.075mm are adopted for sieving.

As an improvement of the technical scheme, the first particle size distribution of the waste asphalt mixture is that the 19mm passing rate is 85-90%.

The implementation of the invention has the following beneficial effects:

the invention provides a control method of a plant-mixed cold regeneration system, which comprises the steps of carrying out first mineral aggregate gradation synthesis according to a theoretical design proportion, and measuring second mineral aggregate gradation in the actual production process; comparing the first mineral aggregate gradation with the second mineral aggregate gradation to determine the accuracy of the gradation; and adjusting the crushing unit, the screening unit and the weighing unit in the production system according to the grading accuracy. The control method can quickly regulate and control the production system according to the grading accuracy, improves the control accuracy, and improves the uniformity and the comprehensive performance of the plant-mixed cold-recycling emulsified asphalt mixture.

Drawings

FIG. 1 is a schematic diagram of a cold plant recycling system of the present invention;

FIG. 2 is a flow chart of a method for controlling a cold plant recycling system according to the present invention;

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, the invention discloses a plant mixing cold recycling system, which comprises a crushing unit 1, a screening unit 2, a weighing unit 3 and a mixing unit 4; the crushing unit 1 and the screening unit 2 are used for treating waste asphalt mixture (RAP material); the weighing unit 3 includes a first weighing unit 31 (not shown in the drawings) for weighing the new aggregate, a second weighing unit 32 (not shown in the drawings) for weighing the used asphalt material, and a third weighing unit 33 (not shown in the drawings) for weighing the ore powder.

Correspondingly, referring to fig. 2, the invention also discloses a control method of the plant mixing cold regeneration system, which comprises the following steps:

s1: determining the mixing proportion of the waste asphalt mixture, the new aggregate, the mineral powder and the emulsified asphalt in the plant-mixed cold-recycling emulsified asphalt mixture;

specifically, the proportioning design can be carried out according to the method in annex F in JTG/T5521-2019, and can also be carried out according to the method in annex D in JTGF 41-2008; the compounding synthesis can also be carried out according to the method in the applicant patent CN 201910369872.8. The difference of the above proportioning synthesis method is that: in the corresponding specification of the field, the proportion design is carried out only by adopting the first particle size distribution of the waste asphalt mixture; in yet another invention of the applicant, the first and second particle compositions of the mix are used as a common standard for formulation. Wherein, the first particle grading is the grading obtained by directly screening (without removing asphalt) the waste asphalt mixture after drying and crushing; the second-level composition is the composition obtained by extracting and screening the waste asphalt mixture (after asphalt is removed).

Preferably, the method in CN201910369872.8 is adopted for proportioning synthesis; the mixture obtained by the proportioning synthesis method has high comprehensive performance. In addition, the mixture obtained by the method has stronger correlation between theoretical mineral aggregate gradation and actual mineral aggregate gradation, can more accurately reflect the gradation accuracy, and improves the control accuracy of a plant mixing cold regeneration system.

S2: carrying out gradation synthesis according to a matching proportion, and determining the first mineral aggregate gradation of the plant-mixed cold-recycling emulsified asphalt mixture;

specifically, S2 includes:

s21: extracting and screening the waste asphalt mixture to obtain a second particle grading;

the waste asphalt mixture contains waste asphalt, and the waste asphalt is combined with part of mineral aggregates. When the asphalt is not removed, the whole asphalt is thicker; after the asphalt is removed, the whole is thin. Thus, the first particle size distribution is different from the second particle size distribution.

S22: carrying out grading synthesis according to the proportion obtained in the step S1 to obtain a first mineral aggregate grading;

specifically, the second particle grading of the waste asphalt mixture, the grading of the new aggregate, the grading of the mineral aggregate and the proportion of the three are graded and synthesized to obtain the first mineral aggregate grading.

S3: taking the plant-mixed cold-recycling emulsified asphalt mixture produced actually, extracting and screening to determine the second mineral aggregate gradation of the recycling mixture;

specifically, the plant-mixed cold-recycling emulsified asphalt mixture is extracted to remove emulsified asphalt and old asphalt; and then screening to obtain a second mineral aggregate gradation.

S4: calculating the accuracy of grading;

specifically, the first mineral aggregate gradation and the second mineral aggregate gradation are compared to obtain the gradation accuracy, and the formula accuracy and the gradation accuracy are effectively fed back, so that the relationship between the performance of the plant-mixed cold-recycled emulsified asphalt mixture and the gradation accuracy is established. Provides a foundation for regulating and controlling a plant-mixed cold regeneration system.

(4) The accuracy of the grading is calculated according to the following set of equations:

wherein, X_iGrading the first mineral aggregate of the ith grade mineral aggregate; y is_iGrading a second mineral aggregate of the ith grade cold-recycling mixture; n is the number of samples. Wherein A measures the gradation accuracy of the mineral aggregate, and A₁Measuring the grading accuracy of the ore materials from the 11 th grade to the 13 th grade; a. the₂Measuring the grading accuracy of the mineral aggregates from the 4 th grade to the 10 th grade; a. the₃The grade accuracy of the ore material from the 1 st to the 3 rd grades is measured.

S5: correcting the plant-mixed cold regeneration system according to the grading accuracy;

specifically, if A is more than or equal to 2, the crushing unit and the screening unit are corrected;

if A is not less than 1.5 and less than 2 and A₃Correcting the crushing unit and the screening unit if the number is more than or equal to 2.5;

if A is more than or equal to 1.5 and less than 2 and A is more than 1.5₃< 2.5, and A₂If the weight is less than or equal to 1.5, correcting the first weighing unit;

if A is more than or equal to 1.5 and less than 2 and A is more than 1.5₃< 2.5, and 1.5 < A₂If the number is less than 2, correcting the first weighing unit and the second weighing unit;

if A is more than or equal to 1.5 and less than 2, A₃Less than or equal to 1.5, and A₂Correcting the second weighing unit if the weighing capacity is more than or equal to 2;

if A is more than or equal to 0.8 and less than 1.5, A₁If the value is less than 1, correcting the second weighing unit;

if A is more than or equal to 0.8 and less than 1.5, A₁Not less than 1, and A₂Less than 1.5, thenCorrecting the third weighing unit;

if A is less than 0.6, the system works normally.

It should be noted that, through analysis of a large amount of actual data, the applicant found that the gradation of screens with different pore sizes can reflect the problems in the production process. If A is more than or equal to 2, the crushing unit and the screening unit of the waste asphalt mixture have problems. It needs to be corrected, and the specific correction means may include: for the crushing unit, the rolling of the crusher, the distance between the jaw plate and the crushing roller, etc. are checked; and for the screening unit, whether the screen is damaged or not, whether the rotating speed of the screen meets the standard or not is checked.

As another example, when A is 1.5. ltoreq.A < 2, the problems of the first weighing cell and the second weighing cell are more reflected. Therefore, when A is more than 1.5₃< 2.5, and A₂If the weight is less than or equal to 1.5, correcting the first weighing unit; when A is more than or equal to 1.5 and less than 2, A₃Less than or equal to 1.5, and A₂Correcting the second weighing unit if the weighing capacity is more than or equal to 2; when A is more than or equal to 1.5 and less than 2 and A is more than 1.5₃< 2.5, and 1.5 < A₂If < 2, the first weighing unit and the second weighing unit are corrected.

It should be noted that the various grades in the present invention can be screened by using standard screens with a pore size of 31.5mm, 26.5mm, 19mm, 16mm, 13.2mm, 9.5mm, 4.75mm, 2.36mm, 1.18mm, 0.6mm, 0.3mm, 0.15mm, 0.075 mm.

The invention is further illustrated by the following specific examples: