Continuous and forced asphalt mixing production method

Abstract

Disclosed is a continuous and forced asphalt mixing production method, which relates to the technical field of concrete processing and includes the following steps of: heating a cold aggregate to obtain a hot aggregate, hot mixing and/or cold mixing the milled materials to obtain recycled materials; blending the hot aggregate, the recycled materials, the powder materials and the asphalt to obtain a premix; temporarily storing the premix in a pre-stirring storage bin and then stirring the premix in a forced stirring cylinder, temporarily storing the obtained finished product materials in a finished product storage bin; in the finished product material loading area, unloading into a storage tank of a finished product material conveying vehicle.

Claims

1. A continuous and forced asphalt mixing production method, comprising the following operating steps: Step 1, pre-treating a cold aggregate and milled materials; Step 2, heating the cold aggregate in a drying cylinder to obtain a hot aggregate, treating the milled materials in a heat transfer manner using hot mixing and/or cold mixing to obtain a recycled material; Step 3, weighing and storing the hot aggregate, the recycled material, powder materials and asphalt; Step 4, blending the hot aggregate, the recycled material, the powder materials and the asphalt to obtain a premix; Step 5, temporarily storing the premix in a pre-stirring storage bin, opening the pre-stirring storage bin to unload the premix when the premix achieves more than 90% of a total capacity of the pre-stirring storage bin, then stirring the premix for 15 to 30 seconds in a forced stirring cylinder, to obtain a finished product material; Step 6, temporarily storing the finished product material in a finished product storage bin; Step 7, in a finished product material loading area, unloading the finished product material in the finished product storage bin into a storage tank of a finished product material conveying vehicle; and Step 8, introducing both asphalt flue gas and water vapor generated in Step 4 and Step 5 into the drying cylinder for a secondary incineration; discharging dust collected in Step 6 into a tail gas absorption and purification device for a tail gas purification and absorption; and introducing a mixed gas of a flue gas and air collected in Step 6 into a burner part of the drying cylinder to be used as a combustion-supporting gas.

2. The continuous and forced asphalt mixing production method according to claim 1, wherein Step 1 comprises: A1, formulating the cold aggregate according to grading requirements; A2, heating the cold aggregate in an inner cylinder of a double-layered split-flow drying cylinder at a temperature of 200° C. to 240° C. to obtain a second hot aggregate; and A3, thermal insulating and temporarily storing the second hot aggregate in a hot aggregate bin at a temperature of 180° C. to 200° C.; Step 2 comprises: B1, conducting primary proportioning on the milled materials according to grading requirements; B2, hot mixing the milled materials at a temperature of 150° C. to 180° C. in an interlayer cavity of the double-layered split-flow drying cylinder in a heat transfer manner, raising the temperature of hot-mixed and recycled materials from 0° C-20° C. to 50° C-120° C. to obtain the hot-mixed and recycled materials; and B3, thermal insulating and temporarily storing the hot-mixed and recycled materials in a hot-mixed and recycled material bin at a temperature of 80° C. to 120° C.; Step 3 comprises: C1, weighing the hot aggregate and the hot-mixed and recycled materials according to requirement of the mixture on gradation and temperature; C2, temporarily storing the weighed hot aggregate in a first storage bin; and meanwhile, temporarily storing the hot-mixed and recycled materials in a second storage bin; C3, recovering the dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin: and C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, and subsequently conveying the petroleum asphalt into a continuous stirring cylinder for blending; Step 4 comprises pre-stirring the hot aggregate in the first storage bin, the hot-mixed and recycled materials in the second storage bin, the powder materials in the third storage bin and the petroleum asphalt in the asphalt storage bin to obtain the premix; and Step 5 comprises temporarily storing the premix in a pre-stirring storage bin, opening the pre-stirring storage bin to unload the premix when the premix achieves more than 90% of the total capacity of the pre-stirring storage bin, then stirring the premix for 15 to 30 seconds in the-a forced stirring cylinder, to obtain the finished product material.

3. The continuous and forced asphalt mixing production method according to claim 1, wherein Step 1 comprises: A1, conducting primary proportioning on fresh materials to grading requirements to obtain the cold aggregate; A2, discharging the cold aggregate into a cold aggregate drying cylinder, heating and drying at a temperature of 200° C. to 300° C. to obtain a second hot aggregate; A3, thermal insulating and temporarily storing the second hot aggregate in a hot aggregate bin at a temperature of 180° C. to 240° C.; Step 2 comprises: B1, conducting primary proportioning on the milled materials according to grading requirements, to obtain cold-mixed and recycled materials; Step 3 comprises: C1, weighing the hot aggregate and the cold-mixed and recycled materials according to requirements of the mixture on gradation and temperature; C2, temporarily storing the weighed hot aggregate in a first storage bin; and meanwhile, temporarily storing the cold-mixed and recycled materials in a second storage bin; C3, recovering the dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin; C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, and subsequently conveying the petroleum asphalt into a continuous stirring cylinder for blending; Step 4 comprises pre-stirring the hot aggregate in the first storage bin, the cold-mixed and recycled materials in the second storage bin, the powder materials in the third storage bin and the petroleum asphalt in the asphalt storage bin to obtain the premix; and Step 5 comprises temporarily storing the premix in the pre-stirring storage bin, opening the pre-stirring storage bin to unload the premix when the premix achieves 90% to 100% of the total capacity of the pre-stirring storage bin, then stirring the premix for 15 to 30 seconds in the forced stirring cylinder, to obtain the finished product material.

4. The continuous and forced asphalt mixing production method according to claim 2, wherein when the hot-mixed and recycled materials are prepared according to grading requirements, in Step 3, a gradation weight ratio of the hot-mixed and recycled materials to the hot aggregate is 1: (1-2).

5. The continuous and forced asphalt mixing production method according to claim 2, wherein when the hot-mixed and recycled materials are prepared, in Step 4, the asphalt flue gas and the water vapor, which are generated when the hot aggregate, the hot-mixed and recycled materials, the powder materials and the petroleum asphalt are pre-stirred, firstly enter the interlayer cavity of the double-layered split-flow drying cylinder for preheating, and subsequently discharged into the inner cylinder of the double-layered split-flow drying cylinder from a discharge port of the inner cylinder for a secondary combustion, and finally the flue gas in the double-layered split-flow drying cylinder is discharged into the tail gas absorption and purification device again for a purification.

6. The continuous and forced asphalt mixing production method according to claim 3, wherein when the cold-mixed and recycled materials are prepared according to grading requirements, in Step 3, a gradation weight ratio of the cold-mixed and recycled materials to the hot aggregate is 1: (1.5-3).

7. The continuous and forced asphalt mixing production method according to claim 2, wherein in C4, Step 2 comprises, weighing the petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in the asphalt storage bin, mixing with water to form a foamed asphalt, and subsequently conveying the foamed asphalt into the continuous stirring cylinder for blending; and, Step 5 comprises, stirring the premix for 15 to 30 seconds in the forced stirring cylinder, to obtain the finished product material controlled at a temperature of 130° C. to 140° C.

8. The continuous and forced asphalt mixing production method according to claim 7, wherein in Step 4, a pre-stirring speed is 20-300 r/min, a stirring time is 0.2-20 min, and a temperature is 160° C-180° C.

9. The continuous and forced asphalt mixing production method according to claim 7, wherein in Step 4, a gradation weight ratio of the hot aggregate to the powder materials to the asphalt is (2-3): (0.2-0.3): (0.5-1).

10. The continuous and forced asphalt mixing production method according to claim 1, wherein, the powder materials are one or more selected from the group consisting of a mineral powder, a stone or a sand; and the asphalt is a petroleum asphalt.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a flowchart of a continuous and forced asphalt mixing production method according to Example 1-1 of the present application;

(2) FIG. 2 is a flowchart of a continuous and forced asphalt mixing production method according to Example 2-1 of the present application; and

(3) FIG. 3 is a flowchart of a continuous and forced asphalt mixing production method according to Comparative example 2-2 of the present application.

DESCRIPTION OF THE EMBODIMENTS

(4) The present application will be further illustrated in detail in combination with the accompanying drawings below.

(5) In one embodiment, a double-layered split-flow drying cylinder is used. The double-layered split-flow drying cylinder is cylindrical in shape and includes a bracket, an inner cylinder rotatably arranged on the bracket, and a housing fixed onto the bracket. A burner is arranged on the bracket, one end of which extends into the inner cylinder in the central axis direction of the double-layered split-flow drying cylinder from one end thereof, for heating and burning the materials in the inner cylinder. An interlayer cavity is formed between the inner cylinder and the housing, a first discharge pipe and a second discharge pipe are arranged at the bottom of the housing, and a partition plate is arranged between the first discharge pipe and the second discharge pipe, so as to achieve the effect of separating materials in the inner cylinder from materials in the outer cylinder without hindering air circulation. Meanwhile, a discharge port is formed on the cylindrical sidewall of the inner cylinder close to the burner. In this case, when the discharge port of the inner cylinder rotates with the inner cylinder to correspond to the second discharge pipe up and down, materials in the inner cylinder can be discharged out of the inner cylinder along the second discharge pipe, while the materials in the interlayer cavity can be discharged out of the interlayer cavity along the first discharge pipe after sufficiently absorbing the high temperature obtained by the burner, so that the heat energy in the double-layered split-flow drying cylinder is fully utilized, the heat loss is reduced, and it is more energy-saving and environmentally friendly. In one embodiment, the double-layered split-flow drying cylinder described above may adopt the drying cylinder provided in Chinese Patent No. CN02102101.5.

(6) In another embodiment, a tail gas absorption and purification device is used. The tail gas absorption and purification device includes successively arranged bag filter, waste gas treatment tower and purified gas discharge chimney, and can be used to absorb and purify tail gas (also referred to as asphalt flue gas). In one embodiment, the tail gas absorption and purification device described above can adopt the structure shown in FIG. 2 of Chinese Patent Application No. CN201010532075.6 entitled “the asphalt flue gas absorption method and device”. That is, an outer cylinder is fixedly connected outside a single-layered drying cylinder, in which one end of the outer cylinder is closed while the other end thereof is opened. A chute and a channel are arranged at the closed end in the outer cylinder to communicate the outer cylinder with the inner cylinder. Thrust plates are arranged on the inner wall of the outer cylinder, and the inner wall/outer wall of the inner cylinder, to enable directional movement of materials. Materials move against the fuel gas stroke in the drying cylinder, get preheated in an interlayer between the outer cylinder and the inner cylinder by the hot inner cylinder and tail gas and then enter the inner cylinder to be continuously heated.

I. Examples: Using Hot Mixing Process

(7) Example 1-1: A continuous and forced asphalt mixing production method, as shown in FIG. 1, including the following operating steps.

(8) Step 1

(9) A1, conducting primary proportioning on fresh materials at a normal temperature according to grading requirements to obtain a cold aggregate, in which the cold aggregate included 18-31.5 mm crushed stone, 10-20 mm crushed stone and 5-10 mm crushed stone at a weight ratio of 21:18:18;

(10) A2, discharging the cold aggregate into an inner cylinder of a double-layered split-flow drying cylinder for combustion, raising the temperature of the double-layered split-flow drying cylinder to 100° C. to dry the cold aggregate first, and then continuing to raise the temperature of the double-layered split-flow drying cylinder to 200° C. to heat the cold aggregate to 180° C. to provide a hot aggregate; and

(11) A3, thermal insulating and temporarily storing the hot aggregate in a hot aggregate bin at a temperature of 180° C.

(12) Step 2

(13) B1, conducting primary proportioning on milled materials at a normal temperature according to grading requirements, in particular, firstly, milling and smashing waste asphalt materials, then screening out the milled materials with a particle size ranging from 10 mm to 30 mm for blending, smashing again the milled materials with a particle size of greater than 30 mm and then sieving, and collecting the milled materials with a particle size of smaller than 10 mm as waste materials in a centralized manner;

(14) B2, hot mixing the milled materials at a temperature of 180° C. in an interlayer cavity of the double-layered split-flow drying cylinder in a heat transfer manner, so as to raise the temperature of the milled materials from 10° C. to 100° C. to obtain a hot-mixed and recycled materials; and

(15) B3, thermal insulating and temporarily storing the hot-mixed and recycled materials in a hot-mixed and recycled material bin at a temperature of 90° C.

(16) Step 3

(17) C1, weighing the hot aggregate and the hot-mixed and recycled materials according to requirements of the mixture on gradation and temperature, so that the gradation weight ratio of the hot-mixed and recycled materials to the hot aggregate was 1:2;

(18) C2, temporarily storing the weighed a hot aggregate in a first storage bin; and meanwhile, temporarily storing the hot-mixed and recycled materials in a second storage bin;

(19) C3, recovering dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin; and

(20) C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, and subsequently conveying the petroleum asphalt into a continuous stirring cylinder for blending.

(21) Step 4

(22) weighing the hot aggregate, the hot-mixed and recycled materials, powder materials and the petroleum asphalt by a weight ratio of 2:1:0.25:0.85, pre-treating the hot aggregate the hot-mixed and recycled materials, powder materials and the petroleum asphalt under stirring in a continuous stirring cylinder at a stirring speed of 100 r/min, to obtain pre-stirred materials at a temperature of about 170° C.

(23) When the hot-mixed and recycled materials in Step 4 were prepared, asphalt flue gas and water vapor generated when the hot aggregate, the hot-mixed and recycled materials, powder materials and the petroleum asphalt were pre-treated firstly enter the interlayer cavity of the double-layered split-flow drying cylinder for preheating, and subsequently discharged into the inner cylinder of the double-layered split-flow drying cylinder from the discharge port of the inner cylinder for secondary combustion, and finally the flue gas in the double-layered split-flow drying cylinder was discharged into the tail gas absorption and purification device again for purification.

(24) Step 5

(25) pre-stirring the mixture obtained in Step 4 for 20 seconds, then storing the mixture in a pre-stirring storage bin, and subsequently, stirring the mixture for 20 seconds in a forced stirring cylinder at the stirring speed of 200 r/min, to obtain finished product materials at a temperature of about 170° C.

(26) In particular, the continuous stirring cylinder as used was Model 800*3500 Concrete Continuous Spiral Stirrer available from Henan Huajin Mechanical Equipment Co., Ltd. The forced stirring cylinder as used was Model JS750 Forced Stirrer Horizontal Biaxial Concrete Stirrer available from Shandong Zeyu Heavy Industry Science and Technology Co., Ltd.

(27) Step 6

(28) temporarily storing the finished product materials in a finished product storage bin.

(29) Step 7

(30) in the finished product material loading area, unloading the finished product materials in the finished product storage bin into a storage tank of a finished product material conveying vehicle.

(31) Step 8

(32) introducing both the asphalt flue gas and the water vapor generated in Step 4 and Step 5 into a double-layered split-flow drying cylinder for secondary incineration; discharging the dust collected in Step 6 into a tail gas absorption and purification device for tail gas purification and absorption; and introducing the mixed gas of the flue gas and the air collected in Step 6 into a burner part of the double-layered split-flow drying cylinder to be used as a combustion-supporting gas.

(33) Example 2-1: A continuous and forced asphalt mixing production method, including the following operating steps.

(34) Step 1

(35) A1, conducting primary proportioning on fresh materials at a normal temperature according to grading requirements to obtain a cold aggregate, in which the cold aggregate included 18-31.5 mm crushed stone, 10-20 mm crushed stone and 5-10 mm crushed stone at a weight ratio of 22:20:19;

(36) A2, discharging the cold aggregate into an inner cylinder of a double-layered split-flow drying cylinder for combustion, raising the temperature of the double-layered split-flow drying cylinder to 110° C. to dry the cold aggregate first, and then continuing to raise the temperature of the double-layered split-flow drying cylinder to 210° C. to heat the cold aggregate to 190° C. to provide a hot aggregate; and

(37) A3, thermal insulating and temporarily storing the hot aggregate in a hot aggregate bin at a temperature of 190° C.

(38) Step 2

(39) B1, conducting primary proportioning on milled materials at a normal temperature according to grading requirements, in particular, firstly, milling and smashing waste asphalt materials, then screening out the milled materials with a particle size ranging from 10 mm to 30 mm for blending, smashing again the milled materials with a particle size of greater than 30 mm and then sieving, and collecting the milled materials with a particle size of smaller than 10 mm as waste materials in a centralized manner;

(40) B2, hot mixing the milled materials at a temperature of 180° C. in an interlayer cavity of the double-layered split-flow drying cylinder in a heat transfer manner so as to raise the temperature of the milled materials from 20° C. to 120° C. to obtain s hot-mixed and recycled materials; and

(41) B3, thermal insulating and temporarily storing the hot-mixed and recycled materials in a hot-mixed and recycled material bin at a temperature of 100° C.

(42) Step 3

(43) C1, weighing the hot aggregate and the hot-mixed and recycled materials according to requirements of the mixture on gradation and temperature, so that the gradation weight ratio of the hot-mixed and recycled materials to the hot aggregate was 1:1.5;

(44) C2, temporarily storing the weighed hot aggregate in a first storage bin; and meanwhile, temporarily storing the hot-mixed and recycled materials in a second storage bin;

(45) C3, recovering dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin; and

(46) C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, and subsequently conveying the petroleum asphalt into a continuous stirring cylinder for blending.

(47) Step 4

(48) weighing the hot-mixed and recycled materials, the hot aggregate, powder materials and the petroleum asphalt by a weight ratio of 1.6:2.4:0.2:0.8, pre-treating the hot aggregate, the hot-mixed and recycled materials, powder materials and the petroleum asphalt under stirring in a continuous stirring cylinder at a stirring speed of 20 r/min, to obtain pre-stirred materials at a temperature of about 180° C.

(49) Step 5

(50) pre-stirring the mixture obtained in Step 4 for 12 seconds, then storing the mixture in a pre-stirring storage bin, and subsequently, stirring the mixture for 20 seconds in a forced stirring cylinder at the stirring speed of 250 r/min, to obtain finished product materials at a temperature of about 165° C.

(51) In particular, the continuous stirring cylinder as used was Model 800*3500 Concrete Continuous Spiral Stirrer available from Henan Huajin Mechanical Equipment Co., Ltd. The forced stirring cylinder as used was Model JS750 Forced Stirrer Horizontal Biaxial Concrete Stirrer available from Shandong Zeyu Heavy Industry Science and Technology Co., Ltd.

(52) Step 6

(53) temporarily storing the finished product materials in a finished product storage bin.

(54) Step 7

(55) in the finished product material loading area, unloading the finished product materials in the finished product storage bin into a storage tank of a finished product material conveying vehicle.

(56) Step 8, introducing both the asphalt flue gas and the water vapor generated in Step 4 and Step 5 into a double-layered split-flow drying cylinder for secondary incineration; discharging the dust collected in Step 6 into a tail gas absorption and purification device for tail gas purification and absorption; and introducing the mixed gas of the flue gas and the air collected in Step 6 into a burner part of the double-layered split-flow drying cylinder to be used as a combustion-supporting gas.

(57) Example 3-1: A continuous and forced asphalt mixing production method, including the following operating steps.

(58) Step 1

(59) A1, conducting primary proportioning on fresh materials at a normal temperature according to grading requirements to obtain a cold aggregate, in which the cold aggregate include 18-31.5 mm crushed stone, 10-20 mm crushed stone and 5-10 mm crushed stone at a weight ratio of 23:25:20;

(60) A2, discharging the cold aggregate into an inner cylinder of a double-layered split-flow drying cylinder for combustion, raising the temperature of the double-layered split-flow drying cylinder to 120° C. to dry the cold aggregate first, and then continuing to raise the temperature of the double-layered split-flow drying cylinder to 220° C. to heating the cold aggregate to 200° C. to provide a hot aggregate; and

(61) A3, thermal insulating and temporarily storing the hot aggregate in a hot aggregate bin at a temperature of 200° C.

(62) Step 2

(63) B1, conducting primary proportioning on milled materials at a normal temperature according to grading requirements, in particular, firstly, milling and smashing waste asphalt materials, then screening out the milled materials with a particle size ranging from 10 mm to 30 mm for blending, smashing again the milled materials with a particle size of greater than 30 mm and then sieving, and collecting the milled materials with a particle size of smaller than 10 mm as waste materials in a centralized manner;

(64) B2, hot mixing the milled materials at a temperature of 180° C. in an interlayer cavity of the double-layered split-flow drying cylinder in a heat transfer manner, so as to raise the temperature of the milled materials from 0° C. to 110° C. to obtain a hot-mixed and recycled materials; and

(65) B3, thermal insulating and temporarily storing the hot-mixed and recycled materials in a hot-mixed and recycled material bin at a temperature of 110° C.

(66) Step 3

(67) C1, weighing the hot aggregate and the hot-mixed and recycled materials according to requirements of the mixture on gradation and temperature, so that the gradation weight ratio of the hot-mixed and recycled materials to the hot aggregate to be 1:1;

(68) C2, temporarily storing the weighed a hot aggregate in a first storage bin; and meanwhile, temporarily storing the hot-mixed and recycled materials in a second storage bin;

(69) C3, recovering dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin; and

(70) C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, and subsequently conveying the petroleum asphalt into a continuous stirring cylinder for blending.

(71) Step 4

(72) weighing the hot-mixed and recycled materials, the hot aggregate, powder materials and the petroleum asphalt by a weight ratio of 3:3:0.3:1, pre-treating the hot aggregate, the hot-mixed and recycled materials, powder materials and the petroleum asphalt under stirring in a continuous stirring cylinder at a stirring speed of 300 r/min, to obtain pre-stirred materials at a temperature of about 160° C.

(73) Step 5

(74) pre-stirring the mixture obtained in Step 4 for 20 seconds, then storing the mixture in a pre-stirring storage bin, and subsequently, stirring the mixture for 30 seconds in a forced stirring cylinder at the stirring speed of 200 r/min, to obtain finished product materials at a temperature of about 160° C.

(75) Step 6

(76) temporarily storing the finished product materials in a finished product storage bin.

(77) Step 7

(78) in the finished product material loading area, unloading the finished product materials in the finished product storage bin into a storage tank of a finished product material conveying vehicle.

(79) Step 8

(80) introducing both the asphalt flue gas and the water vapor generated in Step 4 and Step 5 into a double-layered split-flow drying cylinder for secondary incineration; discharging the dust collected in Step 6 into a tail gas absorption and purification device for tail gas purification and absorption. Meanwhile, introducing the mixed gas of the flue gas and the air collected in Step 6 into a burner part of the double-layered split-flow drying cylinder to be used as a combustion-supporting gas.

(81) Example 4-1:

(82) A continuous and forced asphalt mixing production method differs from Example 1-1 in that: after weighing the petroleum asphalt, the petroleum asphalt first was firstly warm mixed by heating the petroleum asphalt to 140° C. and then adding a surfactant of quaternary ammonium salts (QAS) thereto in an amount of six thousandths of the amount (by weight) of petroleum asphalt.

(83) Example 5-1:

(84) A continuous and forced asphalt mixing production method differs from Example 1-1 in that in C4, petroleum asphalt was weighed according to grading requirements, stored in an asphalt storage bin, mixed with water to form foamed asphalt, and subsequently conveyed into a continuous stirring cylinder for blending, in which the weight ratio of water to petroleum asphalt was optionally 1:80.

(85) Meanwhile, in Step 5, the mixture obtained in Step 4 after pre-stirring for 15 seconds was stored in a pre-stirring storage bin, and subsequently stirred for 20 seconds in a forced stirring cylinder at the stirring speed of 200 r/min, to obtain finished product materials at a temperature of about 140° C.

(86) Example 6-1:

(87) A continuous and forced asphalt mixing production method differs from Example 1-1 in that in C4, asphalt was weighed according to grading requirements, stored in an asphalt storage bin, mixed with water to form foamed asphalt, and subsequently conveyed into a continuous stirring cylinder for blending.

(88) Meanwhile, in Step 5, the mixture obtained in Step 4 after pre-stirring for 15 seconds was stored in a pre-stirring storage bin, and subsequently stirred for 20 seconds in a forced stirring cylinder at the stirring speed of 200 r/min, to obtain finished product materials at a temperature of about 130° C.

(89) Example 7-1:

(90) A continuous and forced asphalt mixing production method differs from Example 1-1 in that in Step 4, the hot aggregate, the hot-mixed and recycled materials, powder materials and the petroleum asphalt were pre-stirred at a stirring speed of 30 r/min for 30 seconds to obtain a premix at a temperature of about 180° C.

(91) In Step 4, the premix, powder materials and the petroleum asphalt were weighed according to asphalt configuration requirements at a weight ratio of 2.5:0.2:0.9. In Step 5, the premix obtained in Step 4 was uniformly mixed under stirring at a stirring speed of 250 r/min for 16 seconds to obtain a finished product material at a temperature of about 169° C.

II. Comparative Examples: Using Hot Mixing Process

(92) Comparative Example 1-1:

(93) An asphalt mixing production method differs from Example 1-1 in that, when preparing the hot-mixed and recycled materials, the milled materials were directly ignited by an open flame and heated to 150° C.

(94) Comparative Example 2-1:

(95) An asphalt mixing production method differs from Example 1-1 in: Step 2, B1, conducting primary proportioning on milled materials at a normal temperature according to grading requirements; B2, mixing the milled materials at 20° C. to obtain cold-mixed and recycled materials, and maintaining the gradation weight ratio of the cold-mixed and recycled materials to the hot aggregate to be 1:9.

III. Test Data Detection

(96) Test 1: Performance of Solidified Asphalt Mixtures

(97) Test Object: the solidified asphalt mixtures prepared in Examples 1-1 to 7-1 were used as test sample 1-1 to test sample 7-1, and the solidified asphalt mixtures prepared in Comparative Examples 1-1 to 2-1 were used as control sample 1-1 to control sample 2-1.

(98) (i) Immersion Marshall Test

(99) 1. The solidified asphalt mixtures prepared in Examples 1-1 to 7-1 and the solidified asphalt mixtures prepared in Comparative Examples 1-1 to 2-1 were immersed in a thermostatic water tank at 60° C. and incubated for 0.5 h;

(100) 2. Test samples or control samples were placed on a Digital Marshall Stability Tester;

(101) 3. The upper and lower press heads of the Marshall tester were put into a thermostatic water tank to arrive at the same temperature;

(102) 4. A loading device was started to enable a test piece to bear the load at a loading speed of 50+/−5 mm/min; and

(103) 5. The stability and the flow value of the test piece were recorded or printed.

(104) According to the highway engineering asphalt and asphalt mixture test procedure (JTGE20-2011), when the nominal maximum particle size of aggregate is larger than 26.5 mm, it is necessary to adopt a large-scale Marshall test piece with the size of 152.4 mm*95.3 mm, the maximum load of the tester is not smaller than 50 kN, and the reading is accurate to 0.1 kN. The curvature inner diameters φ of the upper and lower press heads are 152.4 mm+/−0.2 mm, and the pitch between the upper and lower press heads is 19.05 mm+/−0.1 mm.

(105) TABLE-US-00001 TABLE 1-1 Detected Performance Data of Solidified Asphalt Mixtures Marshall Stability Flow Value Detection Test Object (KN) (0.1 mm) Standard Test sample 1-1 25.5 42.6 JTGE20-2011 Test sample 2-1 26.4 43.5 JTGE20-2011 Test sample 3-1 24.9. 44.8 JTGE20-2011 Test sample 4-1 23.8. 41.5 JTGE20-2011 Test sample 5-1 25.5. 42.1 JTGE20-2011 Test sample 6-1 26.2. 43.3 JTGE20-2011 Test sample 7-1 25.9. 43.8 JTGE20-2011 Control sample 1-1 27.5. 46.8 JTGE20-2011 Control sample 2-1 28.3. 46.5 JTGE20-2011

(106) (ii) Tail Gas (Asphalt Flue Gas) Inspection

(107) Test method: tail gases generated in the Examples 1-1 to 7-1 and the Comparative Examples 1-1 to 2-1 were collected in transparent glass bottles, 5 bottles of tail gases in each group were intercepted for 10-15 seconds, the tail gases were sealed and stored by using rubber caps, labeled respectively, and then recorded with odors respectively in the Table 2-1.

(108) All the transparent glass bottles were sequentially taken out and placed in a laboratory, meanwhile, clean air in a corridor of the laboratory was collected in the transparent glass bottles, and the transparent glass bottles were sealed and stored through rubber caps to serve as blank control samples.

(109) A piece of white paper was then taken as the substrate and the colors inside the transparent glass bottles were observed sequentially and recorded in Table 2-1.

(110) It is understood that asphalt flue gas containing asphalt (asphalt flue gas) is generally mixed with a certain concentration of flue dust, which is brown or black, and has a strong stimulation effect.

(111) TABLE-US-00002 TABLE 2-1 Test object Color and Odor Inspection Test sample 1-1 No apparent colors, no strong offensive odors Test sample 2-1 No apparent colors, no strong offensive odors Test sample 3-1 No apparent colors, no strong offensive odors Test sample 4-1 No apparent colors, no strong offensive odors Test sample 5-1 No apparent colors, no strong offensive odors Test sample 6-1 No apparent colors, no strong offensive odors Test sample 7-1 No apparent colors, no strong offensive odors Control sample 1-1 Gas was brown with offensive odors Control sample 2-1 No apparent colors, no strong offensive odors Blank control samples No colors, no offensive odors (air)

(112) Test results: As can be seen from Tables 1-1 and 2-1, the Marshall stability of the test samples 1-1 to 7-1 were not less than 8 KN, and flow values thereof were also between 15-45 mm, which complies with the general requirements of performance inspection, and the Marshall stability of the control samples 1-1 to 2-1 were not less than 8 KN, but flow values thereof exceeded 45 mm; therefore, performance stability of the control samples 1-1 to 2-1 was much less than that of the test samples 1-1 to test samples 7-1.

(113) Meanwhile, the detection results of the test sample 1-1 to the test sample 7-1 showed that no apparent colors and no strong offensive odors; the blank control sample showed no colors, no offensive odors; the detection result of the control sample 1-1 showed that the gas was brown with offensive odors; the detection result of the control sample 2-1 showed no apparent colors, no strong offensive odors. As can be seen, the above manufacturing method by directly burning milled materials by an open flame will generate asphalt flue gas containing asphalt, which greatly pollutes the environment.

IV. Examples: Using Cold Mixing Process

(114) Example 1-2: A continuous and forced asphalt mixing production method, as shown in FIG. 2, including the following operating steps.

(115) Step 1

(116) A1, conducting primary proportioning on fresh materials at a normal temperature according to grading requirements to obtain a cold aggregate, in which the cold aggregate include 18-31.5 mm crushed stone, 10-20 mm crushed stone and 5-10 mm crushed stone at a weight ratio of 21:18:18;

(117) A2, discharging only the cold aggregate in A1 into the inner cylinder of the cold aggregate drying cylinder, and burning the cold aggregate in a burner at a temperature of 200° C. to obtain a hot aggregate, in which the cold aggregate drying cylinder was Model HG-1001 Horizontal Boiling Dryer avaible from Zhengzhou Huiguan Mechanical Equipment Co., Ltd; and

(118) A3, thermal insulating and temporarily storing the hot aggregate in a hot aggregate bin at a temperature of 180° C.

(119) Step 2

(120) B1, conducting primary proportioning on milled materials at a temperature of 15° C. according to grading requirements, in particular, firstly, milling and smashing waste asphalt materials, then screening out the milled materials with a particle size ranging from 0 mm to 30 mm (which is divided into three ranges of 0-10 mm, 10-16 mm, and 16-30 mm) for blending (i.e., primary proportioning), smashing again the milled materials with a particle size of greater than 30 mm and then sieving, to obtain cold-mixed and recycled materials.

(121) Step 3,

(122) C1, weighing the hot aggregate and the cold-mixed and recycled materials according to requirements of the mixture on gradation and temperature, so that the gradation weight ratio of the cold-mixed and recycled materials to the hot aggregate was 1:2.3;

(123) C2, temporarily storing the weighed a hot aggregate in a first storage bin; and meanwhile, temporarily storing the cold-mixed and recycled materials in a second storage bin;

(124) C3, recovering dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin; and

(125) C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, mixing with water to form foamed asphalt, and subsequently conveying the foamed asphalt into a continuous stirring cylinder for blending.

(126) Step 4

(127) pre-stirring the hot aggregate in the first storage bin, the cold-mixed and recycled materials in the second storage bin, powder materials in the third storage bin and the petroleum asphalt in the asphalt storage bin in a continuous stirring cylinder at a stirring speed of 200 r/min for 15 seconds, to obtain a premix at a temperature of about 180° C., in which the weight ratio of the hot aggregate to the powder materials to the asphalt was 2:0.3:0.5.

(128) Step 5

(129) temporarily storing the premix in a pre-stirring storage bin, opening the bin to unload the premix when the premix achieves more than 90% of the total capacity of the pre-stirring storage bin, then stirring the premix for 15 seconds in a forced stirring cylinder, to obtain finished product materials controlled at a temperature of about 130° C.

(130) In particular, the continuous stirring cylinder as used was Model 800*3500 Concrete Continuous Spiral Stirrer available from Henan Huajin Mechanical Equipment Co., Ltd. The forced stirring cylinder as used was Model JS750 Forced Stirrer Horizontal Biaxial Concrete Stirrer available from Shandong Zeyu Heavy Industry Science and Technology Co., Ltd.

(131) Water vapor generated when the hot aggregate and the cold-mixed and recycled materials (the cold-mixed and recycled materials contains moisture) were pre-stirred firstly enters via ducts from an air intake duct to an interlayer cavity of a cold aggregate drying cylinder for preheating, and subsequently discharged into the cold aggregate drying cylinder from the discharge port for secondary combustion, the flue gas in the cold aggregate drying cylinder was discharged into a bag filter and a waste gas treatment tower of the tail gas absorption and purification device again for purification, and finally the purified tail gas was discharged via a chimney.

(132) Example 2-2: A continuous and forced asphalt mixing production method, including the following operating steps.

(133) Step 1,

(134) A1, conducting primary proportioning on fresh materials at a normal temperature according to grading requirements to obtain cold aggregate, in which the cold aggregate included 18-31.5 mm crushed stone, 10-20 mm crushed stone and 5-10 mm crushed stone at a weight ratio of 22.5:20:19;

(135) A2, discharging only the cold aggregate in A1 into the inner cylinder of the double-layered split-flow drying cylinder, and burning the cold aggregate in a burner at a temperature of 210° C. to obtain hot aggregate; and

(136) A3, thermal insulating and temporarily storing the hot aggregate in a hot aggregate bin at a temperature of 190° C.

(137) Step 2

(138) B1, conducting primary proportioning on milled materials at a temperature of 30° C. according to grading requirements, in particular, firstly, milling and smashing waste asphalt materials, then screening out the milled materials with a particle size ranging from 0 mm to 30 mm for blending, smashing again the milled materials with a particle size of greater than 30 mm and then sieving, to obtain cold-mixed and recycled materials.

(139) Step 3,

(140) C1, weighing the hot aggregate and the cold-mixed and recycled materials according to requirements of the mixture on gradation and temperature, so that the gradation weight ratio of the cold-mixed and recycled materials to the hot aggregate was 1:1.5;

(141) C2, temporarily storing the weighed a hot aggregate in a first storage bin; and meanwhile, temporarily storing the cold-mixed and recycled materials in a second storage bin;

(142) C3, recovering dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin; and

(143) C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, mixing with water to form foamed asphalt, and subsequently conveying the foamed asphalt into a continuous stirring cylinder for blending.

(144) Step 4

(145) pre-stirring the hot aggregate in the first storage bin, the cold-mixed and recycled materials in the second storage bin, powder materials in the third storage bin and the petroleum asphalt in the asphalt storage bin in a continuous stirring cylinder at a stirring speed of 200 r/min for 15 seconds, to obtain a premix at a temperature of about 163° C., in which the weight ratio of the hot aggregate to the powder materials to the asphalt was 2:0.2:1.

(146) Step 5

(147) temporarily storing the premix in a pre-stirring storage bin, opening the bin to unload the premix when the premix achieves more than 90% of the total capacity of the pre-stirring storage bin, then stirring the premix for 15 seconds in a forced stirring cylinder, to obtain finished product materials at a temperature of about 135° C.

(148) Water vapor generated when the hot aggregate and the cold-mixed and recycled materials (the cold-mixed and recycled materials contains moisture) were pre-stirred firstly enters via ducts from an air intake duct to an interlayer cavity of a cold aggregate drying cylinder for preheating, and subsequently discharged into the cold aggregate drying cylinder from the discharge port for secondary combustion, the flue gas in the cold aggregate drying cylinder was discharged into a bag filter and a waste gas treatment tower of the tail gas absorption and purification device again for purification, and finally the purified tail gas was discharged via a chimney.

(149) Example 3-2: A continuous, forced asphalt mixing production method, including the following operating steps.

(150) Step 1

(151) A1, conducting primary proportioning on fresh materials at a normal temperature according to grading requirements to obtain cold aggregate, in which the cold aggregate include 18-31.5 mm crushed stone, 10-20 mm crushed stone and 5-10 mm crushed stone at a weight ratio of 23:25:20;

(152) A2, discharging only the cold aggregate in A1 into the inner cylinder of the double-layered split-flow drying cylinder, and burning the cold aggregate in a burner at a temperature of 220° C. to obtain hot aggregate; and

(153) A3, thermal insulating and temporarily storing the hot aggregate in a hot aggregate bin at a temperature of 200° C.

(154) Step 2

(155) B1, conducting primary proportioning on milled materials at a temperature of 40° C. according to grading requirements, in particular, firstly, milling and smashing waste asphalt materials, then screening out the milled materials with a particle size ranging from 0 mm to 30 mm for blending, smashing again the milled materials with a particle size of greater than 30 mm and then sieving, to obtain cold-mixed and recycled materials.

(156) Step 3

(157) C1, weighing the hot aggregate and the cold-mixed and recycled materials according to requirements of the mixture on gradation and temperature, so that the gradation weight ratio of the cold-mixed and recycled materials to the hot aggregate was 1:3;

(158) C2, temporarily storing the weighed a hot aggregate in a first storage bin; and meanwhile, temporarily storing the cold-mixed and recycled materials in a second storage bin;

(159) C3, recovering dust in the tail gas absorption and purification device, weighing according to grading requirements, and then temporarily storing in a third storage bin; and

(160) C4, weighing petroleum asphalt according to grading requirements, storing the weighed petroleum asphalt in an asphalt storage bin, and subsequently conveying the petroleum asphalt into a continuous stirring cylinder for blending.

(161) Step 4

(162) at a temperature of 200° C., pre-stirring the hot aggregate in the first storage bin, the cold-mixed and recycled materials in the second storage bin, powder materials in the third storage bin and the petroleum asphalt in the asphalt storage bin in a continuous stirring cylinder at a stirring speed of 300 r/min for 15 seconds, to obtain a premix at a temperature of about 170° C., in which the weight ratio of the hot aggregate to the powder materials to the asphalt was 3:0.3:0.6.

(163) Step 5

(164) temporarily storing the premix in a pre-stirring storage bin, opening the bin to unload the premix when the premix achieves more than 90% of the total capacity of the pre-stirring storage bin, then stirring the premix for 15 seconds in a forced stirring cylinder, to obtain finished product materials controlled at a temperature of about 170° C.

(165) Water vapor generated when the hot aggregate and the cold-mixed and recycled materials (the cold-mixed and recycled materials contains moisture) were pre-stirred firstly enters via ducts from an air intake duct to an interlayer cavity of a cold aggregate drying cylinder for preheating, and subsequently discharged into the cold aggregate drying cylinder from the discharge port for secondary combustion, the flue gas in the cold aggregate drying cylinder was discharged into a bag filter and a waste gas treatment tower of the tail gas absorption and purification device again for purification, and finally the purified tail gas was discharged via a chimney.

(166) Example 4-2: A continuous and forced asphalt mixing production method differs from Example 1-2 in: Step 4, weighing the hot aggregate, the cold-mixed and recycled materials, powder materials and the petroleum asphalt according to asphalt configuration requirements, so that the gradation weight ratio of the hot aggregate to the powder materials to the petroleum asphalt was 2.2:0.25:0.8; then, pre-stirring the hot aggregate, the cold-mixed and recycled materials and powder materials in a continuous stirring cylinder at a stirring speed of 200 r/min, to obtain premix at a temperature of about 160° C.; and after 15 seconds, storing the premix in a storage bin, then uniformly stirring the mixture obtained in the previous step and petroleum asphalt in a forced stirring cylinder at a stirring speed of 200 r/min, and then storing the mixture in a finished product storage bin.

(167) Example 5-2: A continuous and forced asphalt mixing production method differs from Example 1-2 in: Step 4, weighing the hot aggregate, the cold-mixed and recycled materials, powder materials and the petroleum asphalt according to asphalt configuration requirements, so that the gradation weight ratio of the hot aggregate to the powder materials to the petroleum asphalt was 2:0.29:0.54.

(168) Example 6-2: A continuous and forced asphalt mixing production method differs from Example 1-2 in: Step 4, weighing the hot aggregate, the cold-mixed and recycled materials, powder materials and the petroleum asphalt according to asphalt configuration requirements; requiring the gradation weight ratio of the hot aggregate to the powder materials to the petroleum asphalt to be 2.9:0.3:0.6.

V. Comparative Example: Using Cold Mixing Process

(169) Comparative Example 1-2: An asphalt mixing production method, which differs from Example 1-2 in that: when the cold-mixed and recycled materials are prepared, the milled materials are directly ignited by open flame and heated to 150° C.

(170) Comparative Example 2-2: An asphalt mixing production method, as shown in FIG. 3, which differs from Example 1-2 in that: there is no pre-blending step, and finally, in Step 5, the weight ratio of the cold-mixed and recycled materials to the hot aggregate is 1:9.

VI. Test Data Detection

(171) Test Two: Performance of Solidified Asphalt Mixtures

(172) Test Object: the solidified asphalt mixtures prepared in Examples 1-2 to 6-2 were used as test sample 1-2 to test sample 6-2, and the solidified asphalt mixtures prepared in Comparative Examples 1-2 to 2-2 were used as control sample 1-2 to control sample 2-2.

(173) (i) Immersion Marshall Test

(174) 6. The solidified asphalt mixtures prepared in Examples to 1-6 and the solidified asphalt mixtures prepared in Comparative Examples to 1-2 were immersed in a thermostatic water tank at 60° C. and incubated for 0.5 h;

(175) 7. Test samples or control samples were placed on a Digital Marshall Stability Tester;

(176) 8. The upper and lower press heads of the Marshall tester were put into a thermostatic water tank to arrive at the same temperature;

(177) 9. A loading device was started to enable a test piece to bear the load at a loading speed of 50+/−5 mm/min;

(178) 10. The stability and the flow value of the test piece were recorded or printed.

(179) According to the highway engineering asphalt and asphalt mixture test procedure (JTGE20-2011), when the nominal maximum particle size of aggregate is larger than 26.5 mm, it is necessary to adopt a large-scale Marshall test piece with the size of 152.4 mm*95.3 mm, the maximum load of the tester is not smaller than 50 kN, and the reading is accurate to 0.1 kN. The curvature inner diameters φ of the upper and lower press heads are 152.4 mm+/−0.2 mm, and the pitch between the upper and lower press heads is 19.05 mm+/−0.1 mm.

(180) TABLE-US-00003 TABLE 1-2 Performance Detection Data of Solidified Asphalt Mixtures Marshall Stability Flow Value Detection (KN) (0.1 mm) Standard Test sample 1-2 20.5 44.1 JTGE20-2011 Test sample 2-2 22.6 40.9 JTGE20-2011 Test sample 3-2 24.1 43.5 JTGE20-2011 Test sample 4-2 22.1 42.2 JTGE20-2011 Test sample 5-2 23.5 40.5 JTGE20-2011 Test sample 6-2 21.8 43.2 JTGE20-2011 Control sample 1-2 27.5 46.8 JTGE20-2011 Control sample 2-2 28.3 46.5 JTGE20-2011

(181) (ii) Tail Gas (Asphalt Flue Gas) Inspection

(182) Test method: tail gases generated in the Examples 1-2 to 6-2 and the Comparative Examples 1-2 to 2-2 were collected by using transparent glass bottles, 5 bottles of tail gases in each group were intercepted for 10-15 seconds, the tail gases were sealed and stored by using rubber caps, labelled respectively, and then recorded with odors respectively in the Table 2-2.

(183) All the transparent glass bottles were sequentially taken out and placed in a laboratory, meanwhile, clean air in a corridor of the laboratory was taken and placed in the transparent glass bottles, and the transparent glass bottles were sealed and stored through rubber caps to serve as blank control samples.

(184) A piece of white paper was then taken as the substrate and the colors inside the transparent glass bottles were observed sequentially and recorded in Table 2-2.

(185) It is understood that asphalt flue gas containing asphalt (asphalt flue gas) is generally mixed with a certain concentration of flue dust, which is brown or black, and has a strong stimulation effect.

(186) TABLE-US-00004 TABLE 2-2 Color and Odor Inspection Test sample 1-2 No apparent colors, no strong offensive odors Test sample 2-2 No apparent colors, no strong offensive odors Test sample 3-2 No apparent colors, no strong offensive odors Test sample 4-2 No colors, no offensive odors Test sample 5-2 No colors, no offensive odors Test sample 6-2 No colors, no offensive odors Control sample 1-2 Gas was brown with offensive odors Control sample 2-2 No apparent colors, no strong offensive odors Blank control samples No colors, no offensive odors (air)

(187) Test results: As can be seen from Tables 1-2 and 2-2, the Marshall stability of the test samples 1-2 to 6-2 were not less than 8 KN, and flow values thereof were also between 15-45 mm, which complies with the general requirements of performance inspection, and the Marshall stability of the control samples 1-2 to 2-2 were not less than 8 KN, but flow values thereof exceeded 45 mm; therefore, performance stability of the control samples 1-2 to 2-2 was much less than that of the test samples 1-2 to the control samples 6-2.

(188) Meanwhile, the detection results of the test sample 1-2 to the test sample 3-2 showed that no apparent colors and no strong offensive odors; the detection results of the test sample 4-2 to the test sample 6-2 showed that no colors; the blank control sample showed no colors, no offensive odors; the detection result of the control sample 1-2 showed that the gas was brown with offensive odors; the detection result of the control sample 2-2 showed no apparent colors, no strong offensive odors. As can be seen, the above manufacturing method by directly burning milled materials by an open flame will generate asphalt flue gas containing asphalt, which greatly pollutes the environment. In addition, only when the weight ratio of the cold-mixed and recycled materials to the hot aggregate in Comparative Example 2-2 is 1:9, and the gradation weight ratio of the cold-mixed and recycled materials to the hot aggregate in Example 1 is 1:2.3, the detected Marshall stability, flow values, colors and odors of the two can be close. As can be seen, the improved production process according to the present application can improve the addition amount of the cold-mixed and recycled materials to the maximum extent, and thus improve the utilization rate of waste asphalt (i.e., milled materials).

(189) These embodiments are merely explanatory and are not restrictive of the application. After reading this specification, those skilled in the art can make various modifications to the embodiments as needed without creative work, which falls within the protection scope defined by the appended patent claims.