Granular activated carbon(GAC) is used primarily for removing odors, tastes, organic constituents and residual disinfectants in water supplies. GAC is made mainly from raw materials such as coconut shell and bituminous coal in the reverse osmosis home drinking water treatment systems. The objective of this study is to compare and contrast bituminous GAC with coconut GAC in terms of their abilities to remove organic substances, residual chlorine and heterotrophic bacterial growth. Tap water passed through filtration system using micro-filter and carbon column and performances were compared during 16 days. The Effluent concentration ratio of TOC for bituminous GAC was lower than that of coconut GAC. Also, the TOC breakthrough of bituminous GAC was longer than that of coconut GAC. The total residual chlorine adsorption of bituminous GAC was 75.0∼90.6%, coconut GAC 75.0∼90.0% respectively. The carbon type did not appear to make a significant difference of this property. Heterotrophic bacterial growth of bituminous GAC was faster than that of coconut GAC in early stage. The bacterial population of bituminous GAC and coconut GAC peaked to 3.4 ×10 exp(5) cfu/㎖ and 4.2 ×10 exp(5) cfu/㎖, respectively after 5 days. The number of bacteria in coconut GAC has been kept up with 10^4∼10^5 cfu/㎖, bituminous GAC 10^3∼10^4 cfu/㎖ respectively since then. For the pre-treatment of reverse osmosis home drinking water treatment system, bituminous GAC is more suitable than coconut GAC because of the high adsorption capacity of TOC and low development of heterotrophic bacteria of bituminous GAC.
II. 실험재료 및 방법
III. 결과 및 고찰