본 연구에서는 삼상역유동층의 수력학적 특성에 대한 연구를 하였다. 실험에 사용한 삼상역유동층반응기는 내부 직경이 11.5 cm이고 높이가 2 m인 투명한 아크릴 컬럼으로 제작되었다. 기체, 액체, 고체로는 각각 공기, 물, 폴리에틸렌 입자를 사용하였다. 고상으로 친유성 입자와 친수성 입자를 모두 사용하였고, 액상으로는 증류수, 기상으로는 공기를 사용하였다. 우리는 고체입자 표면의 성질을 친유성에서 친수성으로 변화시키기 위하여 chlorosulfonic acid를 이용하여 화학적 처리를 하였다. 그 결과 친유성입자의 표면 성질이 친수성으로 변화되었고, 밀도의 증가가 발생하였다. 그리고 친유성/친수성 입자의 수력학적 특성을 분석하기 위하여 정압을 측정하였으며, 임계 유동화 속도도 관찰하였다. 이번 연구의 결과로서, 친유성/친수성 입자를 적당한 비율로 혼합하여 사용할 경우 임계유동화 속도는 감소하는 것을 발견하였다. 이때 밀도의 증가와 표면처리의 영향이 원인이 되었다. 그러나 고체입자의 표면 처리의 영향보다는 밀도 증가의 원인이 유동화에 더욱 큰 기여를 하였다.

We have studied hydrodynamic characteristics of three-phase inverse fluidized bed. Three-phase inverse fluidized bed of this experiment is made of a transparent acrylic column of 11.5 cm inner diameter and 2 m height. Air, water and polyethylene particles were used as the gas, liquid and solid phase, respectively. We used both hydrophobic LDPE(low density polyethylene) and hydrophilic LDPE as solid phase, and distilled water as liquid phase, and air as gas phase. LDPE was chemically treated by chlorosulfonic acid to change the surface from hydrophobic to hydrophilic and then LDPE density was increased. We measured the static pressure and critical fluidization velocity, to analyze the hydrodynamics characteristics of hydrophobic/hydrophilic particles. As a result of this study, we observed that the density increased when the surface of LDPE particles was treated hydrophilically using chlorosufonic acid. As observed, the critical fluidization velocity of hydrophilic particles was decreased. But, this result is more due to density increase rather than surface modification. When we used two kinds of particles(hydrophobic/hydrophilic) together, the efficiency of the inverse fluidization was improved. This comes from the mutual aid between two factors such as density and surface property. Thus, critical fluidization velocity decreased with increasing hydrophilic particle content.

Surface Modification Inverse Fluidized Bed

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