포말부선 기술을 이용한 중국 오염농경지내 비소화합물의 선택적 제거 |
이승우1, 전칠성1, 이은성1, 유경민1, 최준현2, 김현중2 |
1지우이앤이(주) 지반환경사업 2전북대학교 자원에너지공학과 |
Selective Removal of Arsenic Compounds from the Contaminated Paddy Soil in China Using Froth Flotation Technique |
Seungwoo Lee1, Chilsung Jeon1, Eunseong Lee1, Kyungmin Yoo1, Junhyun Choi2, Hyunjung Kim2 |
1Geo-environment Division, JIU Corporation 2Department of Mineral Resources and Energy Engineering, Chonbuk National University |
Corresponding author |
Seungwoo Lee ,Tel: 02-6968-5858, Fax: 02-6968-5853, Email: swlee@jiuene.com
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Received: November 6, 2015; Revised: December 21, 2015; Accepted: April 7, 2016. Published online: July 31, 2016. |
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ABSTRACT |
Effects of grinding time and chemicals dosage in arsenic removal from contaminated paddy soil in China were investigated using lab scale attrition and froth flotation combining process. Arsenic concentration in the field soil was 76.51 mg/kg, exceeding Korean and Chinese standards, and predominant arsenic compounds fraction in sequential extraction was “residual” (over 80%). After wet sieving, soil with >2 mm and < 0.038 mm showed concentration lower than ‘Warning Level’ in Korea. Soil with 0.038-0.075 mm, showing the highest concentration, was discarded since it occupied minor weight fraction (10.1%). Thus soil between 0.075 and 2 mm was only used in the combining process. The highest Arsenic concentration in progeny fragments smaller than 0.038 mm reached up to 981.66 mg/kg after 5 min of attrition. Optimal dosage of collector (C5H11OCS2K) and modifier (Na2S and CuSO4) in froth flotation process for the selective separation of the chipped progeny particles from the parent fragments were determined both as 200 g/ton. Arsenic removal efficiency in froth flotation process was 38.47% and it was increased to 72.74% in additional flotation process, scavenging. Average arsenic concentration after overall process - wet sieving, attrition and froth flotation - was estimated to 16.45 mg/kg. |
Key Words:
Arsenic Contaminated Soils, Attrition Grinding, Froth Flotation, Sequential Extraction, Soil Remediation |
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