A generalized mathematical model used in complex distillation processes, which takes into account interlinks, is presented in this paper. The Petlyuk systems for separating benzene, toluene and o -xylene are simulated by using the homotopy continuation method. Multiple steady state solutions under many different specifications are discovered. The optimal design conditions for the compler distillation process have been found from the simulation results.

From the viewpoint of force balance and fluxes, a general model of diffusion - reaction processes over a catalyst pellet for a non - ideal reaction system is developed. The thermodynamic characteristics of a non - ideal gaseous mixture and the interaction among the fluxes of different species are considered in the model. In addition, this model can be simplified to the conventional Ficks Model, Extended Stefan - Maxwell Model or Dusty - Gas Model. As the foundation for developing general software simulating the diffusion - reaction processes involved over a pellet of catalyst, this model has obvious advantage over others used usually.

Based on the non - ideal Dusty - Gas Model (NDGM) and non - ideal Extended Stefan -Maxwell Model developed in the first part of this paper, and other models used widely for modeling the diffusion - reaction processes over a catalyst pellet, the effect of non - ideal characteristics of the reaction mixture on the predicted effectiveness factors of the catalyst is numerically studied for ammonia and methanol synthesis reactions. Parameter analysis of this effect has also been completed. The computation results and the comparison between the model prediction results and those observed show that non - ideal characteristics should be taken into account for those two reaction systems. NFICK is acceptable for ammonia synthesis reaction, but NESM or NDGM should be adopted for methanol synthesis from CO/CO2/ H2 gas mixture.

In a carbonator tower, the change of CO2 concentration can be reflected by the alteration of some other parameters, such as temperature, pressure, and gas flow in the tower. Based on this consideration , an estimator of CO2 concentration in the tower was formed, which gives the CO2 concentration by calculating the values of temperature, pressure, and gas flow with an algorithm. Considering the time varying environment of the tower, the estimator was designed with self- adaptive attribute, so that it can work effectively under varying environment. By using the estimator, the value of CO2 concentration in the tower can be predicted online. It not only provides useful information for control, but also saves the cost for measuring CO2 concentration.

Simulation computation shows that the performance of a flow reversal reactor depends weakly on the heat transfer parameters but strongly on the global kinetic parameters involved in its transient model. Based on fitting the model prediction of operation performance with the results obtained in bench - scale test, the global kinetic parameters in observed reaction rate equation are modified.Performance prediction and parameter analysis of one - stage flow reversal reactor for SO2 oxidation reaction are completed by using the transient heterogeneous model developed and the parameters modified. Recommendations for designing, operating and optimizing this reactor configuration are given.

A two - dimensional model of water transport is developed to investigate the distribution of water in the membrane, the distribution of the rate of water transport, the distribution of current density in the proton- exchange membrane fuel cell(PEMFC) . The effects of cell temperature, pressure difference between cathode and anode, humidification and thickness of membrane on water transport and distribution of water in the membrane are studied systematically. The conclusions from the model are as follows: ① If the anode is humidified, the water content on the anode side membrane in the reactant gas entrance can be increased; ② The thinner the membrane used, the higher the water content in the membrane;③ The higher the anode is humidified, the more water will migrate from anode to cathode.

A model based multivariable coordinated control algorithm is presented in this paper to meet the complex requirements of industrial process. The control algorithm takes both the control performance of controlled variables and the Ideal Resting Values(IRV) of manipulated variables into consideration. In a system with more inputs than outputs the controller first makes every effort to drive the controlled variables to their setpoints, then if it is possible, makes some of the manipulated variables approach their IRV in economic consideration. For a system with less inputs than outputs, the controller enforcesdiffer-ent control efforts to the controlled variables according to their economic importance. The condition for a unique solution, steady state property and stability of the controller are given in this paper, providing a theoretical guideline for the controller parameter tuning. A FCCU fractionator is introduced here as a case study , for which an multivariable control strategy is developed by using the coordinated algorithm. Simulated results demonstrated that the control algorithm presented in this paper possesses good control performances and practical significance.

A three - dimension gas - particle two - phase flow - reaction model for RFCC riser reactors was developed by using turbulent flow model and lumping kinetics model and integrating flow, heat transfer and reaction. Numerical simulation of four commercial riser reactors was carried out, and the velocity, temperature and concentration profiles in the axial and radial sections were revealed. The calculated parameter values at the outlet of reactor are consistent with the commercial data, which verified the reliability of the flow - reaction model.

The kinetics of alkylation of benzene with propylene over FX - 01 catalyst (a modified H β zeolite) was investigated in a slurry reactor, with internal and extenal diffusion resistance eliminated. The parameters of the model were evaluated and the model was justified by variance and residual analysis.

The convergence of the tridiagonal matrix method for multicomponent distillation is discussed with the principle of numerical analysis. A modified method, bidiagonal matrix method, is put forward. The two methods are compared in their convergence and stability. The application of the tridiagonal and bidiagonal matrix methods to the calculations of many non-ideal multicomponent distillations demonstrates that the latter is more stable than the former.

Systematic studies of heat transfer on the shell - side of a horizontal TEMA - F heat exchanger were carried out using glycerine - water solution and air mixtures. The effects of gas flux, liquid flux as well as flow pattern on heat transfer were studied in detail. The experimental data on stratified flow, intermittent flow and annular flow were correlared by using an enhancement model. The obtained heat transfer correlation can be recommened for design purpose.

In this paper, the method of linear stability analysis is used to study the onset of slugging for oil - gas two - phase flow in a horizontal tube. The relation between the appearance of wavy stratified flow, the formation of slugs and the transition to stable slug flow is quantitatively investigated. A criterion for the transition to stable slug flow is derived from an initial condition of slug growth. The results analysed by the theoretical method compare well with the experimental results.

According to the structure of Mellapak type packing, liquid flow and mixing mechanisms were analyzed in gas - liquid counter - contacting packed column. A new liquid flow distribution mathematical model , specific for Mellapak type packing columns, was presented. Experimental data of the liquid flow distribution measurements agreed quite well with the theoretical prediction. Furthermore, the effects of gas initial maldistribution and gas load on liquid flow distribution were discussed, and the wall zone liquid flow was preliminarily studied.

Manufacturing fuel gases by pyrolyzing municipal refuse is an attractive technology. A laboratory - scale externally heated rotary kiln was designed and developed, and a series of the pyrolysis experiments were done with paper, paper board, waste plastic(including PVC plastic and PE plastic) , rubber, vegetable, wood cloth and orange husk were selected as the sample species of the main organic groups of municipal refuse. The yield and the heating value of the fuel gas were measured; The effects of moisture and size of raw materials on pyrolysis were studied by taking wood chips as an example and the effects of the heating methods on pyrolysis gas yield and the variations of gas composition and heating value during pyrolysis were discussed. At last, the efficiency of pyrolysis, the conversion fraction of fuel gas and gas yield were defined and the results of the experiments were analyzed in terms of such definitions.

The process condition of dephenolization of bisphenol A - phenol adduct is studied, by using the solid decomposition reaction on the basis of thermodynamic property of bisphenol A - phenol and the kinetics of solid decomposition reaction. The process condition is proposed with high quality bisphenol A product. A new method of dephenolization in the production of bisphenol A is developed.

Based on the capacity characteristics of electrical double layer, a new separation method--charge concentration is proposed, and a preliminary experimental study is made. The separation unit is a column packed with powdered activated carbon. Two disc electrodes with some well - distributed apertures are placed separately on the top and under the bottom of the activated carbon. Hard water is fed continuously from the top of the column and the conductivity of the effluent from the bottom is measured with a conductometer. The measured results indicate that ions in water can be removed by applying direct current to the electrodes and then a concentrated solution can be obtained by turning off the current.

The purpose of this paper is to find a new way of fin design to minimize the irreversibilities due to heat transfer and fluid friction and maximize the available work of the working fluid. The general entropy generation formulas for fins are derived at first according to the first and second law of thermodynamics, then a theoretical analysis on cylindrical pin fins and rectangular straight fins is made by using the above formulas. The minimum entropy generation formulas for these two types of fins are obtained and a principle for fin optimization is proposed, where the minimum entropy generation is chosen to be the objective function to be studied. The effect of different parameters on fin entropy generation is discussed in detail in forced convection heat transfer.

In this paper, the basic idea and the structure of Iterative Dynamic Programming algorithm are studied. This method is applied to practical examples of chemical engineering production, and the performance of IDP is tested.

The calculating formula of flow resistance of heat exchanger with longitudinal fluid flow on shell side is derived by the method of regarding zero shear stress line as separate boundary of tube unit. The parameters are derived by experiment , and the variations of flow resistance correspond with experiment data . The maximum deviation with experimental data is less than 6% .

The molecular model of viscous flow of liquid proposed by Eyring is modified from tworespects, namely, the activated energy of viscous flow and the frequency with which activated molecule falls into the hole. A viscosity equation with a single adjustable parameter is obtained, which can be satisfactorily used to correlate and predict the viscosity of various liquid mixtures except aqueous systems. The calculated results show that the agreement with experimental values prevails over Grunberg - Nissan and Wei - Rowley equations etc.