The Influence of Design and Operational Factors on the Removal of Personal Care Products by Constructed Wetlands

Abstract

This research presents the correlation analysis of selected design and operational factors (depth, area, hydraulic and organic loading rate, and hydraulic retention time), and physicochemical parameters (pH, temperature, and dissolved oxygen) of constructed wetlands (CWs) with the removal efficiency of personal care products (PCPs). The results demonstrated that the removal efficiencies of the studied PCPs exhibit a significant correlation with two or more of these factors. The role of plants in the removal of PCPs is demonstrated by the higher performance of planted compared with unplanted CWs due to direct uptake of PCPs and their aerobic biodegradation. The enhanced removal of PCPs was achieved with the use of substrate material of high adsorption capacity and with high surface area in CWs. The removal efficiency of almost all of the studied PCPs revealed seasonal differences, but significant difference was established in the case of galaxolide and methyl dihydrojasmonate. Most of the examined PCPs demonstrated adsorption and/or sorption as their most dominant removal mechanism followed by biodegradation and plant uptake. Therefore, the efficient removal of PCPs demands the integrated design ensuring suitable environment for the occurrence of these processes along with the optimal values of design and operational factors, and physicochemical parameters.