The problem of maintaining the exact ratio between the components in mixtures based on oxychloride cement is described. This problem is solved by the use of additives plasticizing or water-reducing action. The results of studying the effect of the type of additives on the mobility of mixtures and the strength of hardened oxychloride cement pastes are presented. The positive effect of the use of additives based on naphthalene and melamine sulfoformaldehyde was shown. The negative effect of additives based on lignosulfonates on the strength of oxychloride cement pastes has been established. Assumptions about the reasons for the low efficiency of additives based on polycarboxylate esters are indicated. The positive influence of the plasticizing effect of additives on the homogeneity of the microstructure of oxychloride cement pastes is shown. An assumption about the reasons for the increase in strength when using additives based on naphthalene and melamine sulfoformaldehyde is made.
Keywords: oxychloride cement, Sorel cement, plasticizer, water reduction, additive, modification, structure, strength
The granulation process of ammophos in a drum granulator-dryer (DGD) is considered. The main factors affecting the granulation process are considered. The inputs and outputs of the mathematical model of the granulation process are determined. A dynamic mathematical model has been developed for the formation of the equivalent diameter of ammophos granules depending on the flow rate and particle size distribution of the external recycle. Graphs of comparison of simulation results with actual data of normal operation are presented. A graph of the dependence of the equivalent diameter of the granules on the flow rate of external recycling is presented. The model is intended to create a system for stabilizing the granulation mode.
Keywords: ammophos, recycle, granulation, particle size distribution, drum granulator-dryer, modelling, mathematical model