TRANSPORT PARAMETERS OF POTASSIUM FROM DIFFERENT SOURCES IN SOIL COLUMNS

Abstract

ABSTRACT This study aimed to determine some transport parameters of potassium in soil columns by miscible displacement of effluent from a Sewage Treatment Plant (STP). This effluent was collected at different stages of treatment, and potassium chloride solutions were prepared with the same K pulse concentration as the effluent. They were used to conduct a miscible displacement experiment of potassium in soil columns of dystrophic Red Latosol. Both types of solutions contained concentrations of 30 and 32 mg L-1 of potassium. STANMOD software was used to obtain the retardation factor (R) and the Peclet number (Pe) from pore volume and relative concentration. Both retardation factor and solid-water partition coefficient of the soil showed significant results by ANOVA. When assessing KCl solutions, retardation factor was higher than that observed for the effluent, resulting in higher soil-solute interaction. The presence of other competitor cations in the effluent caused less potassium adsorption by the soil. Based on the results, potassium provided a greater groundwater pollutant potential when applied via effluent than solutions of potassium chloride with the same ion concentrations.

Keywords

• breakthrough curves
• environmental contamination
• miscible displacement