• Improving Soil Washing/flushing Process using a Mixture of Organic/inorganic Extractant for Remediation of Cadmium (Cd) and Copper (Cu) Contaminated Soil
  • Lee, Hong-Kyun;Kim, Dong-Hyun;Jo, Young-Hoon;Do, Si-Hyun;Lee, Jong-Yeol;Kong, Sung-Ho;
  • Department of Chemical Engineering, Hanyang University;Department of Chemical Engineering, Hanyang University;Department of Chemical Engineering, Hanyang University;Department of Chemical Engineering, Hanyang University;Department of Chemical Engineering, Hanyang University;Department of Chemical Engineering, Hanyang University;
  • 유/무기산 혼합용출제를 이용한 중금속(카드뮴,구리)오염토양 처리공법(soil washing/flushing) 개선에 대한 연구
  • 이홍균;김동현;조영훈;도시현;이종열;공성호;
  • 한양대학교 화학공학과;한양대학교 화학공학과;한양대학교 화학공학과;한양대학교 화학공학과;한양대학교 화학공학과;한양대학교 화학공학과;
Abstract
The applicability of soil washing/flushing to treat a contaminated soil with cadmium (Cd) and copper (Cu) using a mixture of organic/inorganic extractant was evaluated in laboratory-scale batch and column tests. Citric acid was the effective extractant to remove Cd and Cu from the soil among various organic acids except EDTA. Carbonic acid was chosen as inorganic extractant which was not only low toxicity to environment, but also increasing soil permeability. Moreover, the optimum ratio of organic and inorganic extractant to remove Cd and Cu was 10 : 1, and this ratio of organic and inorganic extractant achieved removal efficiencies of Cd (46%) and Cu (39%), respectively. The increasing flow rate of extractant could explain the phenomena of soil packing when carbonic acid was used with organic extractant (i.e. EDTA and citric acid). Therefore, a mixture of organic extractant with inorganic extractant, especially carbonic acid, could resolve a problem of soil packing when this extractant was applied to a field application to remove Cd and Cu using in-situ soil flushing process.

토양 세척/세정(soil washing/flushing)기법을 적용하여 카드뮴과 구리로 오염된 토양을 처리하기 위해 최적의 유기산 및 무기산 용출제 선정 실험을 batch 및 column test를 통하여 수행하였다. 널리 알려진 EDTA와 비교한 Citric acid는 저분자 유기산 용출제로 구리와 카드뮴의 제거효율이 EDTA를 제외한 다른 유기산 용출제에 비해 처리효율이 높았으며, 탄산은 독성이 가장 낮으면서 토양공극효과를 동시에 수반할 수 있는 무기산 용출제로 확인되었다. 최적의 유/무기산 혼합용출제는 citric acid와 탄산의 혼합 용출제였으며, 최적 농도비는 citric aicd:탄산 = 10:1이었다. 이때의 카드뮴과 구리의 제거효율은 각각 46%와 39%이였다. 탄산은 공극 막힘 현상을 완화시키는 역할으 하는 것으로 확인되었으며, 이는 EDTA + 탄산과 citric acid+탄산에서 용출제의 유량이 점차 증가하는 것을 확인하였따. 따라서, 유/무기산 혼합 용출제는 카드뮴 및 구리로 오염된 토양 처리를 위한 세정 복원기법의 실제현상 적용 시 발생하는 토양공극 막힘 연상을 개선시켜 줄 수 있다.

Keywords: Cadmium;copper;soil washing/flushing;citric Acid;Carbonic acid;

Keywords: 카드뮴;구리;토양세척/세정기법;탄산;

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This Article

  • 2009; 14(2): 17-25

    Published on Apr 30, 2009