Stability of aqueous suspensions of metal oxides and minerals based on aluminosilicates with various particle sizes distribution was measured by the rate of sedimentation, sedimentation volume and zeta potential for various concentrations of solid phase and different pH. Two kinds of TiO2 and one Bentonite were chosen as solid dispersed particles in distilled water. Rheological properties of such materials were monitored. pH was modified by adding of NaOH and HCl aqueous solutions and was measured as complementary parameters. Rheology was measured by rotational viscometer equipped by sensor of coaxial cylinders. Dynamic light scattering method was used for evidence of zeta potential. Isoelectric point was detected from course of function of zeta potential on pH. Range of pH when zeta potential is out of range (-30 30mV) was detected. Outside this region the suspension stability should be higher than inside, which was confirmed by sedimentation and viscometric experiments. With increasing pH both zeta potential and sedimentation velocity decreases

Effect of geometrical parameters on two phase hydrodynamics of airlift reactor is the main topic of present paper. Laboratory scale apparatus with internal circulation loop consists of concentric draft tube, in which a gas bubbles rising. Setup of draft tube inside of reactor is important geometry parameter and has big influence on two phase hydrodynamics. In experiment was studied influence of changes diameter of draft tube to hydrodynamics in airlift reactor. Results of experiments (liquid velocity and gas hold-up) were compared with the simple CFD simulations performed in COMSOL Multiphysics 3.5a. For each point of gas volumetric flow in simulation, were determined conditions of bubble diameter and bubble drag coefficient. Although bubble break-up and coalescence were neglected, the results of numerical simulation are in pretty good agreement with experimental data.Peer reviewe