Study on the relationship between slurry film thickness and rheology of fillers based on film theory

Abstract

The key problem of paste filling technology lies in whether paste can meet the requirements of stope structural parameters on cementing strength, pipe transportation and mining methods on filling performance. The separated paste will cause serious wear and even pipe blockage in the pipeline transportation process. If the paste is separated in the stope, the strength of the filling body will be uneven, and accidents such as delamination and stacking will occur. The occurrence of these situations is extremely unfavorable to the filling operation. Just as the material determines the performance, in order to ensure the paste has excellent filling performance, it is necessary to systematically study the internal relationship between paste filling materials and filling performance. Paste is a complex suspension system composed of aggregate, water, cementing materials and additives. Compared with traditional low-concentration classified tailings slurry, it has the characteristics of wide particle size distribution, high solid content, strong chemical action on particle surface, etc. Under the interaction of these factors, paste presents macroscopic characteristics such as plasticity and stability. These macroscopic characteristics are embodied in rheology, that is, rheological characteristics of paste. The research shows that the rheological properties of paste are affected by the gradation, concentration and cementing material of filling material, and the change of gradation of filling material has the most significant effect on the rheological properties of paste. The change of the micro-level composition causes the change of the rheological properties of the paste on the macro level, thus causing the change of the paste filling performance. In the final analysis, the gradation of the traceable filling material is an important factor that determines the paste filling performance.