Dissolution of Oxygen in Water by Nonporous Hollow Fiber Membrane Contactor

비다공성 분리막을 이용한 수용액 내 용존 산소 조절

  • Lee, Yong-Taek (Dept. of Chem. Eng., College of Eng., Chungnam National University) ;
  • Jeong, Heon-Kyu (Dept. of Chem. Eng., College of Eng., Chungnam National University) ;
  • Ahn, Hyo-Seong (Dept. of Chem. Eng., College of Eng., Chungnam National University) ;
  • Song, In-Ho (Dept. of Chem. Eng., College of Eng., Chungnam National University) ;
  • Jeon, Hyun-Soo (Dept. of Chem. Eng., College of Eng., Chungnam National University) ;
  • Jeong, Dong-Jae (Dept. of Chem. Eng., College of Eng., Chungnam National University)
  • Published : 2007.12.30

Abstract

A nonporous hollow fiber membrane contactor was used to control the concentration of oxygen dissolved in an aqueous solution, which was predicted along the hollow fiber membrane using a computer simulation. The governing ordinary differential equations were derived for the occurrent flows of the feed aqueous solution and the feed gas mixture in a membrane contactor and they were numerically solved using the 5th Runge-Kutta-Verner method with a personal computer, where the program was coded utilizing a software of the Compaq Visual Fortran 6.6. It is found that the concentration of oxygen dissolved in water increases from 30 to 64 ppm as the length of the hollow fiber increases from 0.4 to 1.2 m when the membrane of fibers are equal to be 16,000; the flow rate of the feed gas is kept to be 0.536 mol/sec; its pressure is maintained to be 486 kPa; the flow rate of the water is 16.69 mol/sec. As the flow rate of the water increases from 9.26 to 26.85 mol/sec, the concentration of oxygen decreases from 40 to 20 ppm with the constant fiber length of 0.4 m. Finally, it is observed that the concentration of oxygen increases from 33 to 69 ppm as the pressure of the feed gas increases from 298 to 847 kPa.

비다공성 중공사막 접촉기를 이용하여 수용액 내 용존 산소의 농도를 조절하고자 하였으며, 용존 산소의 농도를 전산모사를 통하여 예측하였다. 공급 기체와 공급 수용액이 같은 방향으로 흐르는 병류 흐름 시스템에 대한 분리막 접촉기 공정 지배 미분 방정식을 5차 Runge-Kutta-Verner 법으로 해석하였다. Compaq Visual Fortran 6.6 소프트웨어로 용존 산소농도 예측 프로그램을 개발하였다. 개발된 프로그램을 사용하여 수치해석을 수행한 결과, 분리막 수가 16,000개로 일정하며 공급기체의 유속이 0.536 mol/sec이고 압력이 486 kPa이며 공급 수용액의 유속이 16.69 mol/sec이고 산소의 몰분율이 0.995으로 유지된 상태에서, 분리막의 길이가 0.4에서 1.2m로 증가함에 따라 용존 산소는 30에서 64 ppm으로 증가하였음을 알 수 있었다. 분리막의 길이가 0.4 m일 때 공급수용액의 유속이 9.26에서 26.85 mol/sec로 증가함에 따라 용존 산소가 40에서 20 ppm으로 감소함을 알 수 있었다. 또한 공급 기체 압력이 298에서 847 kPa으로 증가함에 따라 용존 산소는 33에서 69 ppm으로 증가함을 알 수 있었다.

Keywords

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