Nykyforova N. Substantiation of parameters of hydrotransportation process of minerals with using of drag reducing agents

The method of calculation of critical velocity and hydraulic gradient when slurry flowing in the presence of drag reducing agents, which are flocculants for several components of transporting material is elaborated. The model of process of flocculas formation out of polydisperse solid phase particles and drag reducing agent polymer ions during the enforced flow is elaborated, which takes into account material and polymer characteristics. The criterion of flocculas deliberation by liquid flow in the pipeline is formulated. The dependence of complementary hydraulic gradient on drag coefficient is established that allowed receiving of dependence for calculation of slurry hydraulic gradient with empirical constant independent on transporting material particles size distribution. The dependence for calculation of critical velocity during hydrotransportation of solid materials with the size less than 2 mm in the presence of drag reducing agents is obtained.