Activity of MeO/NMD Catalysts for CO Oxidation

( Dong Sup Doh ) 고려대학교 공학기술연구소 1997 공학기술연구소보 Vol.4 No.-

압력요동특성치를 이용한 유동층연소로에서 다입자계 유 , 무연탄 혼합연소특성 해석

도동섭,박태성,장현태 한국화학공학회 1999 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.37 No.6

내경 0.155 m, 높이 2.2 m의 유동층연소로에서 다입자계 유연탄과 무연탄의 혼합연소특성실험을 수행하였다. 다양한 실험조건에서 압력전달기를 이용하여 압력요동특성치를 측정하여 계산하였다. 압력요동특성치의 통계적 처리과정을 거쳐 압력요동의 표준편차, 정압력, 주진동수, cross-correlation function, power spectral density function을 계산하였다. 다입자계 유연탄과 유연탄올 대상으로 무연탄 혼합비, 석탄분포에 대하여 압력요동특성치와 배출회분입도분포, 배가스조성 등을 측정하여 연소특성을 해석하였다. 유동층연소로에서 혼합석탄의 연소특성 해석은 압력요동특성치중의 압력요동의 표준편차, 평균압력, power spectrum density function을 이용하여 층내의 연소영역 및 연소현상을 외부에서 관측할 수 있음을 알았으며, 주연소영역을 제시할 수 있었으며 연소입자의 분급현상을 측정할 수 있었다. The combustion characteristics of mixture of anthracite and bituminous coal were studied in a fluidized bed (0.155 m-I.D., 2.2 m-height). The pressure fluctuations were measured by a pressure transducer under the various operating conditions. The properties of the pressure fluctuations, such as the standard deviation of pressure fluctuations, static pressure, cross-correlation function, dominant frequency and the power spectral density function, were obtained from the statistical analysis. The pressure fluctuation properties, particle size distribution of ash and composition of flue gas were measured to interpret the combustion characteristics in a fluidized bed combustor of uniform or multi-sized particles of mixed anthracite and bituminous coal have been compared with the particle size distribution, anthracite mixing fraction. From this study, the combustion characteristics of mixed fuels in a fluidized bed combustor could be interpreted by using standard deviation of pressure fluctuation and power spectrum distribution.

현탁 이중기포탑에서 현탄액의 순환특성 및 열전달

도동섭,박찬진,이근후 고려대학교 공학기술연구소 1988 고려대학교 생산기술연구소 생기연논문집 Vol.24 No.1

The mean circulation time and the heat transfer coefficient were investigated in a solid suspended bubble column with draft tube which is installed to form the stabilized flow stream. The effects of gas velocity in the range of 0.016-0.052㎧, particle size in the range of 44-105㎛ and solid concentration in the range of 2-6 vol% on the gas hold-up, circulation time and heat transfer coefficient were studied with gas continuous liquid-solid batch operation. The average gas hold-up increased and the circulation time decreased with increasing gas velocity decreasing particle size and particle concentration. The heat transfer coefficient increased with increasing gas velocity, particle size and particle concentration.

충전유동층(充塡流動層)에서의 입자의 비산(飛散) 및 비출(飛出)

도동섭 고려대학교 공학기술연구소 1975 고려대학교 생산기술연구소 연구보고 Vol.6 No.2

The entrainment and elutriation of calcium carbonate particles were examined in a packed fluidized bed; a stainless steel column of 5cm. inner diameter, 70cm height, and filled with ceramic Raschig rings of 0.8 cm diameter. The increase in an entrainment of homogeneous particles was found to be a logarithmic function, and the elutriation velocity constant of fine particles in the mixed particles was proportional to the 4th power of the fluidization gas velocity, regardless of the ratio of fine particles to coarse one in the bed.

연초제조창의 폐수처리

도동섭,강웅기,서영갑,손명환 고려대학교 공학기술연구소 1970 고려대학교 생산기술연구소 연구보고 Vol.1 No.1

The treatment of waste water containing nicotine was studied by the methods of air oxidation, exposure to sun-light, UV decomposition, precipitation, adsorption with active carbon, and adsorption with activated clay. Of these, only the last three methods appeared to separate the nicotine to a satisfactory level. These methods were compared from an economic point of view and the method of adsorption with activated clay appeared the most feasible. The equipments for a continuous treatment system were also designed.

수직관내를 흐르는 유체의 현탁입자에 의한 열전달속도 증진에 관한 실험적 및 이론적 연구

도동섭,박찬진,최근오 한국화학공학회 1989 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.27 No.5

수직관의 내부를 통하여 흐르는 슬러리와 관벽간의 열전달특성을 연구하기 위하여 수직의 이중관 열교환기에서 슬러리속도와 고체입자의 크기 및 농도를 변화시켜가며 각각의 조건에 따른 열전달계수를 산출하였다. 그 결과 슬러리흐름에서의 열전달속도는 슬러리의 속도 및 입자의 농도가 증가할수록 그리고 입자의 크기가 감소할수록 증가하였으며 실험범위 전반에 걸쳐서 순수한 물의 경우보다 크게 나타났다. 이러한 현상을 설명하기 위하여 액체막으로 둘러 쌓여 있는 고체입자가 관벽과 충돌하면서 발생하는 입자표면의 액체막을 통한 열전달현상을 고려한 모델을 제시하였으며 이에 의해 현탁입자의 유동이 열전달속도에 미치는 영향을 정량적으로 설명할 수 있었다. The study on the heat transfer characteristics between tube wall and slurry flowing through the vertical tube was investigated. To calculate heat transfer coefficient, experiments were conducted by varying slurry flow rate, particle size and concentration of particles and it was found that the rate of heat transfer in the slurry flow was larger than that in the simple water flow and it increased as the slurry flow rate and concentration of particles increased and particle size decreased. A heat transfer model considering the effect of the collision of suspended solid particles with its clinging film with the surface of copper tube was proposed and from which the heat transfer characteristics could be explained very well.

Ca - alginate 겔 입자가 첨가된 Airlift 반응기에서 산소의 물질전달에 관한 연구

도동섭,이근후 한국화학공학회 1993 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.31 No.4

Ca-alginate 겔 입자가 첨가된 외부순환식 airlift 반응기에서 실험적으로 기체 체류량과 물질전달 계수를 측정하였다. 총괄 기체 체류량과 액상 물질전달 계수는 기체유속이 증가함에 따라 증가하였으며, 입자농도가 증가함에 따라 조금 감소하였다. 기체 체류량과 물질전달 계수는 고체입자 크기에는 별 다른 영향을 받지 않았다. Higbie의 침투이론과 Kolmogoroff의 등방난류이론으로부터 물질전달에 대한 모델을 제안하였으며, 실험결과에 비교적 잘 맞았다. To investigate the performance of external-loop airlift reactors, the gas holdup and the volumatric mass transfer coefficient were determined experimentally in an airlift reactor with Ca-alginate gel beads. The results show that the overall gas holdup and liquid-phase mass transfer coefficient increased with increasing gas velocity but slightly decreased with increasing particle concentration. The particle size had no clear effect on the variation of gas holdup or oxygen transfer. A mass transfer model was proposed based on Higbie's penetration theory and Kolmogoroffs isotropic turbulence theory, and it compared fairly with experimental data.

현탁기포탑에서 고체입자가 기체 체류량과 물질전달에 미치는 영향에 관한 연구

도동섭,박찬진,정병훈,홍성범 고려대학교 공학기술연구소 1987 고려대학교 생산기술연구소 생기연논문집 Vol.23 No.1

The influence of suspended inert solid particles on the gas holdup and mass transfer was investigated by measuring expansion of height and CO₂ concentration at a solid suspended bubble column in the presence of 0-6% by volume of particles and 47.50-135.48 ㎛ by particle diameters. It was found that at a given superficial gas velocity the gas hold up and mass transfer was smaller than those without solid particles and this decrease was greater at high solid concentration and large particle size. An energy balance method and eddy cell model was proposed to explain this behavior.

유동층내의 입자의 운동상태 및 열전달

도동섭 한국화학공학회 1970 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.8 No.1

The movements of silica-alumina particles in a gas fluidized bed of 28 cm I. D. were studied with a modified thermistor probe. The probe developed in this study was found to be able to measure the mass velocity and direction of particle flow in a fluidized bed. Pasticles moved upwards near the center of the bed and downwards near the wall. The magnitude of the mass velocity and the cross-sectional area through which the particles move upwards increased with increasing air velocity and position from the bed support. The profiles of heat transfer coefficient between the surface of a small heating element and the bed were found to be very similar to those of particle velocity, which explains that the heat is transfered mainly by the movements of solid particles and the effect of fluid is minor.

" 현탁입자가 물질전달속도증진에 미치는 영향의 차원해석적 연구 "

도동섭,박찬진 고려대학교 공학기술연구소 1986 고려대학교 생산기술연구소 생기연논문집 Vol.22 No.1

In order to investigate the influence of suspended inert solid on the enhancement of mass transfer rate, multiple regression analysis was done for correlative equation derived from dimensional analysis of variables using limiting current density for the reduction of ferric cyanide obtained from a rotating disk electrode system. Multiple regression analysis was conducted with eight different particle surface to disk surface ratios, with Reynolds numbers in the range of 17,800-89,200 and with volume fraction of particles in the range of 0.05-0.25. It was found that the limiting current density increased with rise of Reynolds numbers and with that of volume fraction of particles, but it decreased with rise of particle surface to disk surface ratio in the range of large particle size and increased with rise of particle surface to disk surface ratio in the range of small particle size.