The sludge flotation/thickening apparatus equipped a micro-bubble generating pump was used to investigate micro-bubble generating properties on operational parameters. We evaluated micro-bubble generating properties as results to be operated the apparatus by operational parameters which are pump discharge pressure, air/water ratio(A/W ratio), air flow rate, and water flow rate. Micro-bubble generating efficiencies in pumps without recycling flow and with 50% of recycling flow was found to be very efficient on optimum A/W ratio from 1.06 to 3.62% and optimum A/W ratio from 1.05 to 4.06%, respectively. In condition of 3.6% of A/W ratio, we showed that the apparatus could be generated 36,000 ppm of micro-bubble concentration to be optimum treatment efficiency in sludge thickening process.

Abstract
 1. 서 론
 2. 재료 및 방법
  2.1. 미세기포 발생장치
  2.2. 흡입공기량/미세기포 발생량 및 슬러지 부상농축효율측정
  2.3. 미세기포 발생펌프형 슬러지 부상농축장치
 3. 결과 및 고찰
  3.1. 공기 및 물 유량비(A/W ratio)에 따른 미세기포 발생효율 : 가압수 미반송
  3.2. 공기 유입량에 따른 미세기포 발생효율 : 가압수 반송
  3.3 공기 및 가압수 유량에 따른 미세기포 발생효율
  3.4. A/W ratio에 따른 미세기포 발생효율
 4. 결 론
 참 고 문 헌

• 이창한(부산가톨릭대학교 환경행정학과) | Chang-Han Lee (Department of Environmental Administration, Catholic University of Pusan)
• 안갑환(부산가톨릭대학교 환경행정학과) | Kab-Hwan Ahn (Department of Environmental Administration, Catholic University of Pusan) Corresponding author
• 박종원(일솜주식회사) | Jong-Won Park (ILSOM Co., Ltd. R&D CENTER)