A new liquid-diffusion cell with metallic diaphragm has been applied to investigate the diffusion coefficients of five binary systems containing longchain molecules at various concentrations. The parameter values of the empirical poly-nominal correlating diffusion coefficient with concentration have been obtained by data fitting. A new equation correlating diffusion coefficient with concentration has been derived (22) This equation and other six equations used for comparison have been applied for prediction to 23 systems(207 points)with grand % deviations shown below: * With one empirical parameter It shows that, among the equations without empirical parameter, Eq. (22) of this paper has the lowest value.

The Martin-Hou equation of state is applied to liquid-liquid equilibrium. Excellent results are obtained for binary systems by using two binary Interaction parameters, which are temperature-dependent over a wide temperature range, but can be taken as constant over the narrow temperature range of 30 to 40 degrees. The prediction of VLE for binary systems at low pressures based on LLE data of binary systems are demonstrated. The results thus calculated agree with those determined experimentally.

A method in proposed for correlating heat transfer coefficient in spiral-fluted tubes upon analysis of the distribution of heat transfer resistance. A correlation for turbulent single-phase flow is thus obtained, Valid for both single-and multiple-start spiral-fluted tubles, are a wide range of Prandtl number (Pr = 0.7 to 35).

By modifying a mathematical model for distillation with two liquid phases so as to accommodate thermally coupled distillation with two liquid phases, this paper proposes an algorithm based upon the modified Naphtali-Sandholm method. The structures of the Jacobian matrix and its submatrices of all types, and formulae for computation of their nonzero elements are given. The multiple phase flash method, combined with a comparison of free energies for determination of the liquid phase split in stage, is employed. Separation of the butanol-water-propanol ternary system is used to corroborate the method mentioned above. Satisfactory results are obtained.

A numerical method for calculating the rheological behavior of polymeric liquids from their molecular models is presented, and several dumbbell models of polymer molecules are then calculated in terms of this method. Answers are given to some problems which could not be solved theoretically. The calculated results indicate that the dumbbell models can be used to simulate the rheological behavior reasonably well once the finite extension of molecules and non-linearity of intramolecular forces arc included in the models, and that the configuration-dependent coefficient of friction included in the FENE dumbbells can only change the flexibility of molecules when elongated, but cannot result in the "S"-shaped curves of elongation viscosity, and that inclusion of the hydrodynamic interaction in the Hookean dumbbells does improve its capability of simulating the rheological behavior of polymer liquids. The numerical method has showed new light on the molecular theory of polymer rhe-ology, and will possibly be used in the numerical simulation of complex flow to replace the constitutive equations of continuum mechanics by molecular models.

Stress corrosion crack ing (SCC) was seriously imperilling the safety of a Japanese Industrial Standard JIS-SPV36 steel ammonia sphere of volume 5200 m3 and diameter 21.5m. Chemical composition of the corrosion products has been analyzed, a survey of the stress corrosion cracks propagation characteristics at welded joints has been made, and statistical analysis of the results based on the record of internal inspection of the sphere in open status and of experimantal studies have been worked out. Then the reliability of the sphere wasevaluated. An approach Spray metal coating to prevent the ammonia sphere from SCC has been proposed. Spray coating on the internal surface of the sphere during the period of annual regularmaintenance in December 1986 has proven to be effective on practical trial.

A two-dimensional mixing pool stochastic model is proposed for simulating liquid flow and mass transfer in a packed column, by which the concetra-tion profiles of the liquid and gas phases can be computed. The main features of this model are: (a) any complicated liquid flow pattern can be closely simulated by adjusting the flow and the mixing among mixing pools in both the radial and the axial directions, (b)the stochastic nature of liquid distribution is fully considered in the model computation. Both theoretical and experimental investigations show that the drop of mass transfer efficiency with increasing column diameter or column height is mainly attributed to non-uniform liquid flow, intensified axial mixing, and imperfect radial mixing.

It is found that the jet-pump has four types of flow a, b, c, d, of which b is the only desirable in operation. So it is essential to find the criteria tor flow regime transitions. On the basis of momentum, energy and mass balance principles, the following theoretical criteria were obtained: These criteria were found to agree well with experimental results. If ΔPB falls between cril and cri2, the flow regime b would be obtained.

A numerical method is propose for studing the condensation mechanism of specially shaped fin tubes, which include the radially ridged fin tube(R. tube) and the saw-tooth shaped fin tube(S. T. Tube). The results show that the effects of surface tension and fin roughness differ with peripheral position, and can be related to the structural parameters of the tube, the properties of the condensate and the magnitude of the heat flux. In general, both surface tension and fin roughness play important roles in condensation heat transfer for the S. T. tube, while two-dimensional surface tension play a leading role for the R. tube.

Peng-Robinson equation of state was modified to represent vapor-liquid equilibria tor hydrogen-hydrocarbon binary systems. A new expression of the temperature dependent parameter for the supercritical gas hydrogen, and binary interaction parameters were introduced to improve description of vapor-liquid equilibria for 19 binary systems. Results show that this work is superior to previous researches, and to Mathias RKS and CCOR equation of state for heavy hydrocarbons, C6 to C16, in particular. Moreover, estimations of p-V-T relation and second virial coefficients of hydrogen from our modification are in good agreement with the experimental data.

The secondary nucleation kinetics of potassium chloride crystallization from brine at 40℃ is investigated in the suspension density MT range from 51 to 146 g/1 and at agitation speed N 820 r/min and 650 r/min in a 2.5 IMSMPR crystallizer with clear liquor overflow. The power index i in the kinetic equation is independent of both Mr and N, and is 2.9. The power index j is 1. 1 at 820r/min. The coefficient of the kinetics equation is highly sensitive to agitation speed. Too high agitation speed should not be used in crystalli-zers not only for energy saving but also for coarse product. High suspension density and long retention time should be used in industrial crystallizers for high productivity and coarse product size respectively.

The flow behaviours of three extraction systems were studied. Experiments on 30%TBP (OK)-water system showed the obvious effect of wettability of dispersed phase on perforated plate upon holdup. When amplitude was lower than 0.6cm, axial dispersion was not serious, and the reciprocating plate extraction column was found to possess good performance for the 30% TBP(OK)-water system. The flooding characteristics of isopropyl acetate-water (10% acetic acid, 7% sodium sulfate)system and heavy benzene-ammonia water(0.2% phenol) system were investigated. The sizes of two plant-scale columns for the recovery of acetic acid and phenol were estimated.

According to Danckwerts surface-renewal model, an approximate expression for calculating CO2 absorption and desorption rate by hot potash solution and a criterion of the pseudo-first order reaction were derived (see Eq. 19, 15a). These were in close agreement with experimental data. A new method in which a promoter can be appreciated was proposed. By using a stirred reactor, the absorption and desorption rates of CO2 by hot potash promoted by hexanediamine(HDA) were measured. It was dem-onstrsted that HDA had similar catalytic effect as diethanolamine(DEA).

Isohyrores on the phase diagrams of multicoponent salt-water systems are often necessary in technological design. We obtained 650 points on isohy-drores at 25℃ for Na+, K+, Mg2+/Cl--H2O, 2Na+, Mg2+/2Cl-, SO42--H2O systems by using Pitzers theory of electrolyte solution. These data are useful in estimating saturation point of salt of brine, and mixing process of brines.

Isobaric vapor-liquid equilibrium data of three binary systems (dichlorodi-fluoromethane- octafluorocyclobutane, chlorodifluoromethane -octafluorocyclobutane. and hexafluoropropylene-octafluorocyclobutane) at 0.986 MPa were determined with an isobaric vapor-liquid equilibrium apparatus. The equilibrium data are satisfactorily correlated by the Martin-Hou Equation of state(81)and can be used for process design successfully.

By using the trapping microphotographical technique, the drop size distribution of the aviation kerosene and carbon tetrachloride mixture-deionized water system has been measured in three stirred tanks of 184, 287 and 494 mm in diameter with impellers of the frame-plate type. Based upon the mechanism of dispersion, model relations have been proposed and the model parameters determined by experiments. So a relation of the variation of drop size distribution with equipment geometry, operation parameters and phase ratio has been given. According to this relation, some relevant scale-up criteria have been obtained.

On the basis of analysis of weeping distribution phenomena and data on valve trays, a unified semiempirical model is proposed. The new correlation gives satisfactory results for F-1, V-4, Hy-contact and A-type valve trays.