Conventional wastewater treatment plants (WWTPs) do not fully remove micropollutants. Enhanced treatment of sewage effluents is being considered or implemented in some countries to minimize the discharge of problematic micropollutants from WWTPs. Representative enhanced sewage treatment technologies for micropollutant removal were reviewed, including their current status of research and development. Advanced oxidation processes (AOPs) such as ozonation and UV/H2O2 and adsorption processes using powdered (PAC) and granular activated carbon (GAC) were mainly discussed with focusing on process principles for the micropollutant removal, effect of process operation and water matrix factors, and technical and economic feasibility. Pilot- and full-scale studies have shown that ozonation, PAC, and GAC can achieve significant elimination of various micropollutants at economically feasible costs(0.16-0.29 €/m3). Considering the current status of domestic WWTPs, ozonation and PAC were found to be the most feasible options for the enhanced sewage effluent treatment. Although ozonation and PAC are all mature technologies, a range of technical aspects should be considered for their successful application, such as energy consumption, CO2 emission, byproduct or waste generation, and ease of system construction/operation/maintenance. More feasibility studies considering domestic wastewater characteristics and WWTP conditions are required to apply ozonation or PAC/GAC adsorption process to enhance sewage effluent treatment in Korea.

도시 하수는 미량오염물질의 수환경 배출 주요 점오염원이며 인구증가 및 도시화로 향후 도시인근 수자원 수질에 미치는 영향이 증가할 것으로 예상된다. 규제측면에서는 그 위해성이 명확하고 대표성이 있으며 현실적 제거 목표 달성이 가능한 오염물질에 대하여 수질기준정립이 예상된다. 하수 유출수에서 미량오염물질 제거를 위한 산화 (오존, UV/H2O2), 흡착 (분말활성탄), 막분리 (NF, RO)) 세가지 공정에 대한 연구가 활발한데, 본 발표에서는 위와 같이 도시 수환경 미량오염물질 이슈와 초고도 하수 처리공정에 대해 살펴보겠다.

Water samples from several wastewater treatment plants and two industry drains in Gyeongsangbukdo were investigated for concentration levels of micropollutants. Samples were taken totally four times from May to November of 2008 and tested for seven factors including pesticide, 1,4-Dioxane and Perchlorate which had been big issues for Nakdong river because of their contaminations. As results, 2,4-D, Alachlor, and BEHA were not detected while BEHP was detected at some sampling sites. 1,4-Dioxane and Perchlorate were also detected in wide ranges from several sampling sites. Therefore, continuous supervising and monitoring systems needed to be invested for proper management for micropollutants since those micropollutants could affect human health and aquatic system with low concentration levels.