The flow fields of gas and simulating droplet are investigated with the DANTEC 55X laser doppler anemometer on 300mm rotating stream tray (RST). The clarified flow features include: (1)Axisymmetrical flow. (2)The tangential velocity ut distribution is composed of an inner forced vortex and an outer quasi-free vortex. (3) The upflow (axial velocity uz >0) is mainly in the annular cross-sectional area greater than 1 / 2 radius, and a downflow occurs in the area over the liquid receiving-distributing disk. (4)In the main two-phase contacting area, ut and uz are found to be well correlated as equations 1 and 2 respectively. (5)The radial velocity is about one-tenth of ut or uz. The respective purposes of the internally and externally-oriented trays in design can be established from the two-phase flow feadtures. Using a two-equation k-ε. model and a finite-difference procedure, a numerical model for calculating the turbulence flow on RST is also given in this paper. The computed velocities and pressures are compared with the experimental data, and satisfactory agreement is obtained.

A mathematical model of secondary current distribution for the gas-evolving electrode is presented on the basis of mass balance and voltage balance. A modified Bruggman equation and the degree of electrode screening are used in the theoretical analysis. The current distribution and the factors affecting the distribution are determined experimentally with the segmented electrode method and a computer controlled voltage measurement system. The curves computed with the model show good agreement with experimental results.

A generalzed dynamic equation based on aerosol dynamics and reaction kinetics for a CVD reactor was derived, and a calculation method for particle size distribution and film growth rate in the CVD reactor was developed. The effects of operation parameters on particle formation and film growth process were simulated with this method. By means of a dimensionless parameter H, the optimal condition for particle formation and film growth in the CVD reactor could be determined quantatively.

Crystal packed-bed crystallizer is designed and used to separate and purify para-dichlorobenzene from a mixture of para- and ortho- dichlorobenzene. The effect of operation parameters such as the height of crystal packed-bed, reflux ratio, feed concentration and agitation rate on the separation performance of the crystallizer are investigated, and the operation process of crystallization is analyzed.

A new method for the estimation of chemical potential in molecular simulation, the Reference Test Particle method, is proposed. This method is more efficient than the particle-insertion method and overcomes the drawback of underestimate obtained with the particle-removal method. Application of the new method to hard sphere fluids at ρσ3 = 0.50 and o.65 and Lennard-Jones fluids at ρσ3 = 0.65, 0.70, 0.80 and o.90 along the isotherm kT/ ε= 1.2 shows that the RTP method has the advantages of fast convergence, high efficiency and good accuracy.

The pre-saturation technique is used to extend the validity of the gas stripping method to the determination of infinite dilution activity coefficients in multicomponent solvent systems. A ternary mixture of methanol-acetone-benzene was studied at 298.15K with this method. The values measured were well correlated by the UNIQUAC equation.

From the Gibbs-Duhem equation, there exists a one-to-one correspondence of variables between pure fluid and binary fluid mixture under constant pressure. By analogy, gE models similar in form to equations of state (EOS) are obtained. The gE model corresponding to the Martin-Hou EOS is selected for detailed study. Three dif ferent temperature functions are considered. Calculations show that the gE model can be used successfully to correlate liquid-liquid equilibrium and vapor-liquid equilibrium data.

A correlation for predicting liquid diffusion coefficients at infinite dilution was developed based on theoretical models. In the correlation, a concept of pseudoviscosity was used, which could be determined from the viscosity of mixtures, or estimated from the viscosity of pure components. The average absolute deviation for 50 diffusion coefficient data was 10.6% by using the pseudoviscosities calculated from the pure component viscosities, while those calculated by the Wilke-Chang equation and Tyn-Calus equation were 22.9% and 14.2% respectively.

Crystal size distribution (CSD) transients and internal instability of continuous crystallization processes were studied systematically. The dynamic models describing continuous crystallization were solved by using some new mathematical techniques. And a software was developed which can simulate the sustained limit-cycle behavior of crystallization and the transients in CSD caused by outside disturbances. By means of this software, the influence of various system parameters on CSD stability and the causes of cycling were studied. Simultaneously, transient responses of CSD for a step change in outside operating condition, such as feed flow rate and concentration, product removal rate, fines destruction rate, classifier flow rate, etc., were investigated in detail. The results observed experimentally in a 200L KCl complex crystallizer and a 10L NH4Cl complex crystallizer in this study and the experimental data presented by previous researchers verified that our softwares are suceessful.

This paper deals mainly with the regeneration of coked B-02 catalyst which has been run in the two stage industrial adiabatic beds for nearly 4000 hours. Experiments were carried out in an internal recycle gradientless reactor. The intrinsic kinetic model for burning regeneration of the coked catalyst was obtained by using non-linear least-square method. The kinetic model can be expressed simply in terms of the oxidation of carbon and hydrogen because the coke, in fact, is polynuclear aromatics composed of carbon and hydrogen. The kinetic equations for carbon oxidation For the first adiabatic bed catalyst For the second adiabatic bed catalyst The kinetic equations for hydrogen oxidation For the first adiabatic bed catalyst For the second adiabatic bed catalyst

The mechanism of compression of filter cake when the pressing pressure is greater than the filtering pressure is analysed in this paper. The equations of compression and hydraulic pressure distribution are derived in which the creep effect of cake is taken into consideration . The hydraulic pressure distribution in cake during filtration and compression is detected. The experiments were carried out under different pressing and filtering pressures, and the experiment data show good agreement with the equations developed.

In this paper a new tray efficiency definition for not only ideal or non-ideal binary multicomponent but also reactive systems is presented. The bizarre behaviour(Eoyi≈ 0, Eoyi<0, Eoyi≥0, Eoyi→∞) of Murphree efficiency in multicomponent or reactive systems can be avoided by using the new tray effieiency definition. The epuations for calculating the tray efficiencies are defined and derived theoretically. A comparison of the tray efficiencies from experimental data of reactive distillation process with those calculated theoretically is also made.

This paper deals with the experimental research of heat tranafer to liquid sodium with low Pe and high temperature and its incipient boiling wall superheat under a positive pressure in an annulus. The experimental research and theoretical analysis show the semi-empirical correlations obtained coincide with the experimental data very well. In the experiments the inner diameter of the annulus is 6mm and the outer diameter is 10mm The inner wall is heated by electrically heating element, and the outer wall is heat-insulated.

The mass transfer models for hemodialysis(HD), hemofiltration(HF) and hemodiafiltration(HDF) in hollow fiber modules have been established as a generalized duct convective mass transfer model, in which the dialysis-filtration number is taken as the model parameter. A numerical solution of the model is obtained by using the orthogonal collocation method. The influence of some variables on mass transfer characteristics is discussed. The results obtained by orthogonal collocation are compared with those obtained by the finite-difference method and exact analytical solution. With regard to computing-time, the orthogonal collocation has an advantage over the finite-difference method.

Specimens stressed at yieiding point in acidic occluded solutions were tested to simulate the mechanical and environmental states within stress corrosion cracks for "1Cr13 steel /0.5mol/L Cl-" system, and to determine the corrosion rates as well as the electrochemical behaviour of crack tips at different propagating stages. The experimental potential / pH diagrams depicting kinetic and thermodynamic behaviours inside cracks as well as mechanical and environmental effects on occluded cell corrosion were constructed. A critical pH value (about 4.1 at 90℃) was found from the "corrosion rate/pH" curve, "potential / time" curves, and potential / pH diagrams, below which passive-active transition occurred at crack tips and corrosion rate increased rapidly. Both stress and acidification caused a higher corrosion rate and a greater critical pH value.

A physical model called parallel-tube model based on the analogy between fluid flow in a packed bed and in an empty pipe is established and a method for the velocity prediction is pressented. It is found that the prediction is close to the experimental study and is better than those methods developed previously.

The solubility of CO2 in a mixed solvent of propylene carbonate (P.C.) with methyldiethanolamine (MDEA) and water was measured at CO2 partial pressure of one atm within the temperature range of 10- 35℃ and at 25℃ over a wide range of CO2 partial pressures. The effect of the miscibihty of P.C. and water in the mixed solvent on the solubility of CO2 was investigated. As a result, immiscible mixed solvent shows significant improvement in absorption of CO2,which can be explained by the chemical equilibrium theory. Appropriate compounding of mixed solvents was determind.