In this paper, a model is proposed for the prediction of the width of arching in hoppers
resulted from sudden changes in solid feed rates. Such changes in solid feed rate usually
come from the collision on the surface of the moving-bed in the standpipe. The model also
takes into account the effect of the powder height in the standpipe of the hopper. The
model proves to be adaptable for predicting operational conditions to avoid arching by
keeping constant powder height in the main standpipe with interstitial gas flow.

A comprehensive study on various internal energies for the dipolar hard sphere fluids,
including Stockmayer fluids, the mixtures of Lennard-Jones and Stockmayer and Stockmayer
fluids and the electrolyte solutions is reported based on the perturbation theory and mean
spherical approximation. Compared with the results of molecular simulations, it is shown
that the perturbation theory is better than the mean spherical approximation.

Based on the fundamental thermodynamic principle the relationships of the residual
properties, the property changes of mixing and the excess properties between the
hypothetical solution of unreacted independent species and the equilibrated solution of
actual species have been established. The hypothetical solution provides a way of reducing
the dimensionality of problem and simplifying the analysis.

A general equation is proposed for predicting the liquid viscosities of petroleum fractions
based on a generalized pseudocompound method in which pure hydrocarbons and undefined
hydrocarbon mixtures or petroleum fractions are treated as a hypothetical pure substance
called pseudocompound which is characterized only by a boiling point and a density. T he
equation is tested by using the liquid viscosities of the petroleum fractions of typical
American crude oils and crude oils from major oil producing areas. Good agreement between
the predicted and experimental viscosities for the petroleum fractions is obtained.

Membrane microfiltration fermentation (MMF) with cell recycling was successfully applied to
the production of glucose oxidase (GOD). A plate microfiltration module was found suitable
for such purpose. By feeding whole medium in MMF, the productivity of GOD was much higher
than that by feeding glucose alone. With increasing dilution rate the enzyme productivity
increased and average enzyme activity decreased. The enzyme productivity of MMF under D =
0.12 h-1 and 0.20 h-1 were 3871 and 3945 U.h-1 respectively, which was about 3 times as
that of batch fermentation (BF) and the average enzyme activity was still as high as 37
U.mL-1 under D = 0.12 h-1. The relative efficiency of MMF applied to low yield strain was
higher than that applied to high yield strain.

Demulsification of emulsified water-in-oil droplets was worked out with the employment of
wetting coalescence materials. Demulsification is carried out in conventional stirred-
column and packed-column. Among the four kinds of natural fibers and two kinds of inorganic
materials tested, natural fiber A, originated from wood shavings was found to give the best
performance of demulsification. The demulsification efficiency can exceed 96.5% when
demulsification conditions are optimized. The packed-column showed much better performance
both in terms of demulsification efficiency and repeated use of the recovered oil phase for
extracting cadmium in simulated wastewater. Operating variables governing the
demulsification efficiency were investigated.

In the established apparatus, the conversion ratios of cellulose sulfation (X) under
different sulfation conditions were measured. The range of temperature is from -5 ℃ to +5
℃, and the H2SO4 concentration is from 3.1 mol× L-1 to 4.5 molL-1. The experimental
results were used for the establishment of the kinetic model for cellulose sulfation. With
the model X values and yield of NaCS Y can be calculated, thus the reaction in accordence
with H2SO4 concentration was determined to be third order3.

In this paper, the standard k-ε two-equation model is adopted to numerically simulate
fully developed fluid flow and heat transfer in a spiral finned tube within a cracking
furnace for ethylene manufacturing. By variable transformation, the original 3-D problem is
converted into a 2-D problem in spiral coordinates. The algorithm of SIMPLEC is used to
study the fully developed fluid flow and heat transfer in the spiral finned tube at
constant periphery temperature and constant axial heat flux. The computed results agree
pretty well with the experimental data obtained from the industry. Further studies on the
fluid flows and temperature profiles at different Reynolds numbers within straight and
spiral finned tubes are conducted and the mechanisms involved are explored. It is found
that with the spiral finned tube, pressure drop increases to a great extent whereas heat
transfer tends to be decreased.

A generalized steady-state model is being developed for an internal heat integrated
distillation column (IHIDiC). A procedure incorporating the Newton-Raphson method is
devised for solving the model equations.Separation of an ethanol-water binary mixture is
simulated and analyzed with the model. Two pinch points are found within the process,
making the separation extremely difficult and expensive. Two sharp fronts in the
temperature and the composition profiles are being observed. With the introduction of heat
integration, satisfactory separation may be obtained in a limited number of stages with
lower reflux ratios. Increasing the pressure difference between the rectifying and the
stripping sections, however, would bring about a reduced relative volatility between the
two components involved, creating adverse separation performances. It is obvious that
optimization of the IHIDiC is of prime importance.