Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Korean Chemical Engineering Research
Journal Basic Information
Journal DOI :
The Korean Institute of Chemical Engineers
Editor in Chief :
Volume & Issues
Volume 23, Issue 6 - Dec 1985
Volume 23, Issue 5 - Oct 1985
Volume 23, Issue 4 - Aug 1985
Volume 23, Issue 3 - Jun 1985
Volume 23, Issue 2 - Apr 1985
Volume 23, Issue 1 - Feb 1985
Selecting the target year
A Mathematical Model for Predicting Slab Temperature in Reheating Furnace
Lee, Geun-Seong ; Yoo, Eun-Jae ; Song, Dong-Ik ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 137~137
A mathematical model based on two-dimensional heat transfer for predicting slab temperature in reheating furnace was derived. This model takes into account the radiation heat transfer between the slab and atmosphere gases and furnace walls, and the conduction heat transfer by temperature gradient in the length and the thickness direction within the slab. The slab temperature was calculated from the derived equation by using the difference method. To vertify this model, actual slab average extraction temperature which could be estimated by the temperature after No.4 roughing mill using a pyrometer was compared with the calculated value. Results from this model showed that the accuracy of predicting slab temperature enhanced about
Kinetics of Sodium Chloride- Ethanol- Water System in CMSMPR Crystallizer
Kim, Ho-Dong ; Park, Hyo-Sik ; Shin, Young-Jun ; Lee, Chul-Soo ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 145~145
The kinetic equations were experimentally studied for a salting out system of NaCl brine and ethanol using CMSMPR(Continuous Mixed Suspension Mixed Product Removal) crystallizer. Experiment was carried out in the steady state with varying agitator speed to establish the critical agitator speed and RPM dependence on the nucleation rate. While growth rate was found to be proportional to the supersaturation, beyond the critical agitator speed the nucleation rate was found to be proportional to 0.8 power of supersaturation and to suspension density and to 3.2 power of RPM.
Heat Transfer Characteristics of a Fluidized Bed Coal Combustor
Choe, Jong-Chan ; Kim, Yeong-Jae ; Mun, Sang-Heup ; Kim, Sang-Don ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 153~153
In a cylindrical fluidized bed combustor-pilot plant (
), combustion experiments were carried out with the domestic high ash content anthracite (3400 Kcal/Kg) coal. The effects of coal mean size (0.49, 0.62 mm), air velocity (23-76 cm/s) and bed temperature (
) on heat transfer coefficients between either fluidized bed, free-board and vertically immersed cooling tubes, temperature profiles along the bed height and combustion efficiency have been determined. The heat transfer coefficient exhibited a maximum value with air velocity. However, it increased with bed temperature and decreased with particle size. The temperature profiles along the bed height became flattened with increase of air velocity. Whereas, combustion efficiency decreased with air velocity but it increased with bed temperature.
Transient Behavior of Hollow-Fiber Beaker Fermenter
Park, Tai-Hyun ; Kim, In-Ho ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 161~161
A mathematical model for a hollow-fiber beaker fermenter was presented to investigate time-dependent behaviour of the fermenter. Tube side of the fermenter was modelled as n-mixed tanks and the shell side was segregated from the tube side by membrane. To compare numerical simulation with experimental data, Saccharomyces cerevisiae was cultured in the shell side. When the initial substrate concentration in the shell side was low, history of outlet tube-side substrate concentration has a complex pattern instead of monotonous profile. Membrane permeability was observed to decrease rapidly with the growth of cells.
Heat Transfer in Coal Slurry-Gas-Solid Fluidized Beds
Kim, Sang-Done ; Kang, Yong ; Lee, Ho-Kyung ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 167~167
Heat transfer characteristics of two (coal slurry-gas, coal slurry-solid) and three (coal slurry-gas-solid) phase fluidized beds have been determined in a
QVF glass column fitted with an axially mounted cylindrical heater. Effects of coal slurry velocity (4-12 cm/s), air velocity (0-14 cm/s), slurry viscosity (14-24 mPa.s) and particle size (1.7-8.0 mm) on heat transfer coefficient were examined. In three phase slurry fluidized beds, heat transfer coefficient generally increased with gas velocity and particle size but it decreased with slurry viscosity. However, the coefficient went through a maximum value with liquid or coal slurry flow rate. The bed porosity at which the maximum heat transfer coefficient occured in coal slurry-solid system coincide with the maximum energy dissipation rate. The heat transfer coefficients in three phase coal slurry fluidized beds can be estimated from the surface renewal and isotropic turbulence theories.
A Study on the Drift behind Single Air Bubble Using Two Liquids-Interfaces
Shin, Jeong-Ho ; Ju, Chang-Sik ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 179~179
For investigation of the drift behaviors behind single air bubble, interfaces between two insoluble liquids were introduced. In this system, the shape variation of the interface was clearly observed when a bubble was passing through the interface. A drift profile based on the major axis of the bubble in the upper phase of the solution is influenced by the bubble size. For each system whose viscosity of the lower phase is as large as or larger than that of the upper phase, the drift profile based on the major axis of the bubble in the lower phase is nearly independent of both the bubble size and the physical properties of the upper phase of the solution. The averaged drift in this experiment decreases with the decrease of the viscosity of the lower phase and ultimately approaches Darwin's total drift. To examine the coincidence between Darwin's total drift and data obtained in this work, the averaged drift area of each system was correlated to the viscosity of the lower phase. The correlation shows as follows.
The drift area extrapolated to that of zero viscosity was 1.11, and this value is nearly coincident with that of Darwin's total drift area, 0.95.
Liquid Mixing Characteristics in a Continuous Flow Stirred Tank Reactor
Kim, Tae-Ok ; Kang, Woong-Ki ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 189~189
The mixing characteristics of liquid was investigated in a continuous flow stirred tank reactor (CFSTR) with a 6-bladed turbine impeller. The inlet and the outlet were located at the bottom center and the top edge of the reactor, respectively. For the CFSTR, three zones (inlet zone, impeller zone and recirculation flow zone) with different mixing characteristics were assumed and the theoretical conversions based on the assumption were compared with the experimental results obtained from the irreversible second order reaction system. For the case of the lower inlet flow rate and the lower agitation speed, the experimental results showed that the mixing characteristics of the inlet and the recirculation flow zones were considered to be that of macrofluid. For the higher inlet flow rate as well as the higher agitation speed, however, the inlet zone showed the perfect mixing nature of microfluid with a considerable dilution of the macrofluid of recirculation. Also, the higher agitation speed, the larger was the volume of the impeller zone, in which the microfluid characteristics could be excellently assumed.
Sintering of the Supported Nickel Model Catalysts
Song, Heon-Sik ; Ihm, Son-Ki ;
Korean Chemical Engineering Research, volume 23, issue 3, 1985, Pages 199~199
The sintering behaviors of the nickel model catalysts supported on
were studied under wet hydrogen atmosphere as a function of sintering time and temperature. Two types of initial crystallite size distribution, i.e., the aggregated and the uniformly dispersed, could be obtained by controlling the sputtering conditions. The same region of a specimen was examined with a transmission electron microscope after each heat treatment to follow the change of each nickel crystallite. The surface of nickel crystallite was believed to be in the oxide state as observed by the electron spectroscope for chemical analysis. The various events which had occurred during the first one hour were identified, and they could be explained by applying all the possible sintering mechanisms, i.e., the crystallite migration, the atomic migration and the combination of the two.