In the asphalt processing, the agglomeration problem of asphalt high viscosity agent will affect the effective performance of its performance. Solving this problem is crucial to improving the quality of asphalt.
First, optimizing the addition method of the thickener is the key first step. When adding the thickener, appropriate dispersing equipment and slow addition methods should be used. For example, using a high-speed shear disperser, the asphalt high viscosity agent is slowly added to the asphalt system during the asphalt mixing process. Through high-speed shear force, the thickener can be quickly dispersed in the asphalt to avoid agglomeration caused by excessive local concentration. At the same time, the selection of the addition point is also very important. Try to choose an area where the asphalt is more vigorously stirred, such as the middle or bottom of the mixing tank, so that the thickener can be fully mixed with the asphalt as soon as it enters the asphalt system to prevent it from agglomerating on the surface.
Secondly, pre-treatment of the thickener can effectively reduce agglomeration. The thickener can be pre-dispersed before addition, for example, the thickener is mixed with a small amount of diluent or surfactant. The diluent can reduce the viscosity of the thickener and make it easier to disperse. Surfactants can change the surface properties of the thickener, making it more lipophilic or hydrophilic, thereby enhancing its compatibility with asphalt. For example, using an appropriate amount of non-ionic surfactants can form an adsorption layer on the surface of the thickener, reduce its surface energy, prevent the mutual attraction between the thickener particles, and reduce the occurrence of agglomeration.
Furthermore, it is also very important to control the process parameters during the processing. Temperature and stirring speed are two key parameters. The appropriate temperature can reduce the viscosity of asphalt and is conducive to the dispersion of the thickener. Generally speaking, it is more appropriate to process within a temperature range above the softening point of asphalt but not causing excessive flow of asphalt. For example, for ordinary road asphalt, the processing temperature can be controlled between 140-160℃. At the same time, the stirring speed should be moderate. Too slow will not allow the thickener to be fully dispersed, and too fast may introduce too much air, generate bubbles, and affect the quality of asphalt. The optimal stirring speed is determined through experiments so that the thickener can be evenly dispersed in the asphalt to avoid agglomeration caused by insufficient or excessive stirring.
Finally, start with the quality and formula of the thickener itself. Choose a thickener with a smaller particle size and uniform distribution. The smaller particle size can increase the contact area between the thickener and the asphalt, which is beneficial to its dispersion in the asphalt. At the same time, optimize the formula of the thickener, reduce the ingredients that easily cause agglomeration, or add anti-agglomeration additives. For example, add some ingredients with steric hindrance effects to the formula of the thickener. When the thickener particles are close, these ingredients can prevent the particles from further agglomerating, thereby fundamentally solving the agglomeration problem and improving the dispersibility and stability of the asphalt high viscosity agent during processing.
