Device for producing modified asphalt and method for producing modified asphalt by using device

Abstract

The invention discloses a device and a synthetic method for producing modified asphalt. The device comprises a mixing device provided with a raw material inlet, wherein the mixing device is communicated with a heat insulation tower; the heat insulation tower is provided with a mixture inlet and a discharge hole, the mixture inlet is formed on the lower part of the heat insulation tower, and the discharge hole is formed on the upper part of the heat insulation tower; and matrix asphalt and modifier are fully mixed and delivered to the heat insulation tower for synthesizing, fluid flows through gaps of shell and tube heat exchangers from bottom to top to exchange heat in a large area, and the mixture follows rise of the fluid level and relative motion of the shell and tube heat exchangers, so that the flowability of the mixture is ensured, and the mixture is heated more uniformly and fully.

Description

technical field [0001] The invention relates to a mixing and heating device, in particular to a device for producing modified asphalt using base asphalt and a modifier as raw materials and a synthesis method for producing modified asphalt using the device. Background technique [0002] The sediment produced in the oil refining process is collectively referred to as petroleum base asphalt or base asphalt. Base asphalt is a binder for flexible pavement construction. It has good cohesiveness, impermeability, insulation and chemical stability. It is Commonly used road construction materials. Due to the temperature sensitivity of the base asphalt, its rigidity and strength decrease at high temperatures, and the pavement softens, while at low temperatures, it is easy to produce shrinkage cracks and other pavement cracking phenomena. It is necessary to add modifiers to the base asphalt to modify it to improve its performance. Mechanical properties at high and low temperatures. Th...

AI Technical Summary

Problems solved by technology

[0005] 1. Since the melting and swelling reaction tank with agitator in the tank can only ensure the partial fluidity of the mixture, the modifier is easy to float above the melting and swelling tank due to its small specific gravity, and most of the mixture in the tank has low fluidity. Poor, when the mixture is heated and swollen in the swell reaction tank, it is heated unevenly, and during the mixing process, modifiers such as rubber powder will release a large amount of heat when they swell and swell in the asphalt, which is difficult to control, resulting in Some of the modified asphalt is aging, some of the modified asphalt is not fully swollen, and the modifier is agglomerated;

[0006] With the increase in the amount of modifiers such as rubber powder, the viscosity of the modified asphalt will increase, and the above-mentioned modified asphalt is partially aging and partially incompletely swollen. At the same time, the viscosity of the modified asphalt increases and the fluidity Therefore, the quality of modifiers such as rubber powder in the existing modified asphalt is strictly controlled within 20% of the total mass of the mixture, and the road performance of the modified asphalt mixture is due to the improvement On the other hand, due to the limitation of the amount of modifier, the amount of asphalt is relatively large, resulting in high cost of rubber asphalt mixture, which is very uneconomical

[0007] 2. Since there is less air in the swelling reaction tank, the swelling reaction between rubber powder and other modifiers and asphalt in the swelling reaction tank is mild, and it takes 2-4 hours to complete, and the reaction can only be done in one pot. Continuous production cannot be realized

[0008] 3. Due to the small heat exchange area of ​​the expansion reaction tank, the reaction is relatively mild. It is necessary to store heat by pre-heating the base asphalt to meet the heat required in the initial stage of the reaction. However, pre-heating the base asphalt will easily lead to the aging of the base asphalt; preheating The base asphalt makes the base asphalt and the modifier partially swell during the mixing process, which increases the viscosity of the material and causes uneven mixing.

[0009] 4. There is no waste gas recovery device in the device, and the high-temperature wastewater and toxic waste gas generated during the mixing process are discharged into the atmosphere, which is not conducive to environmental protection and endangers the health of people around the equipment

[0011] 1. The material located near the edge and inner wall of the horizontal mixing tank is difficult to mix evenly; and the paddle agitator and rubber powder agitator usually need to be rotated at high speed to fully mix the material. However, due to the high viscosity of the modified asphalt, the flow Poor performance makes it difficult to achieve high-speed rotation and stirring; and the continuous heat release during the swelling reaction process will further increase the viscosity of the modified asphalt with the increase of the temperature in the tank, thereby deepening the influence on the rotation speed of the agitator. The materials are difficult to mix, and it is still inevitable that some rubber asphalts will age and some rubber asphalts will not fully swell

In the modified asphalt produced, most of the modifiers exist in the modified asphalt in its original physical state, which makes the appearance of this type of modified asphalt rough and hard. The cost of road construction increases, which is uneconomical

[0012] Especially with the increase of modifier content, the viscosity of modified asphalt will also increase. In the process of using this device to produce modified asphalt, the amount of modifier will be strictly limited, making it difficult for this device to be used in production At present, the development prospect is promising, and the production of high-volume modified asphalt with renewable resources such as waste tire powder and phenolic resin powder recovered from electronic waste as modifiers

[0013] 2. The device has not fundamentally solved the problem of small heat transfer area and long reaction time

[0014] 3. The device is still not equipped with an exhaust gas recovery device, and the exhaust gas generated by the melting and swelling reaction is discharged directly, polluting the atmosphere, and the gaseous rubber asphalt in it is not fully recycled

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