하절기 오염 소하천 정화를 위한 생물여과조와 식생대의 Pilot Test

Abstract

The objective of this study is to recover the contaminated ditch by using a biofilter filled up with waste-concrete media and vegetation bed. Two systems were tested for elimination of organic compounds, turbidity, nitrogen and phosphate. System 1 is three-stage system which consisted of one biofilter and two vegetation bed, system 2 has three-stage system consisted of one biofilter. one vegetation bed (four bed) and one media trench operated in series. In system 1, HRT of biofilter was 4 hour, and Oenanthe javanica was planted in two vegetation bed. In system 2, HRT of biofilter was varied 2 hours and Persicaria chinensis was planted on the top of the biofilter. And Oenanthe javanica, Hydrocharis asiatica, Salvinia natans were planted in four bed of a vegetation bed and the second vegetation bed of system 1 was rebuilt to a media trench bed. The elimination rate of BOD and turbidity was over 90% m both systems The mean elimination rates 40 - 50 % (system 1). 30-40%(system 2) for T-N and 40-50% (system 1), 30-40% (system 2) for T-P. T-N and T-P elimination performance of system I was a little higher(10%) than that of system 2. Results showed that vegetation bed are not efficient in reducing T-N and T-P. It was considered that HRT of vegetation bed of both systems was much lower (l -2hr) than that of conventional system(5 -20days).