IMPACT OF VARIABLE HYDRAULIC GRADIENT ON FILTERING PROCESS IN POROUS COLUMN

The effect of temporal variation in hydraulic gradient on the impurity pulse transport in a porous column has been investigated experimentally. Temporal variations in the hydraulic gradient, and hence flow intensity, were organized by periodic changes in the pressure gradient at the ends of the column. The measurements were carried out for the case of horizontal column position as well as for the cases of inclination of the porous column relative to the horizontal axis. An analysis of the effect of time-varying flow on the efficiency of the filtration process was carried out. It has been shown that the effect of pulsation is only noticeable when filtering highly concentrated contaminants, when concentration convection develops against the background of the main advective flow. At the same time, the presence of pulsations only changes the rate of impurity transport, not the amount of impurity leached. The inclination of the porous layer significantly accelerates contaminant transport, but the additional introduction of flow pulsations in the inclined porous layer has a weak effect on filtration efficiency.