Engineering Commons^™

Process Optimization By Flow Sheet Simulation, Larry Dale Gaines

Doctoral Dissertations

"PROPS, (Process Optimization System), has been used to simulate and optimize the Universal Oil Products solid phosphoric acid catalyst process for producing gasoline. PROPS, a modified version of CHESS (Chemical Engineering Simulation System), performs a complete design and economic evaluation of the process for each set of independent variables. The computational time during optimization was reduced by the use of a regression equation to determine K-values as a function of temperature and pressure. K-value data used for the regression was generated from the Chao-Seader correlation using mixtures of the gasoline components to be encountered during optimization. The regression equation produces …

Transition Boiling Of Normal Pentane From A Horizontal Flat Gold Surface, Ronald M. Canon

Doctoral Dissertations

"The characteristic boiling curve for Normal Pentane was determined at 1 atmosphere pressure with particular attention devoted to the transition boiling region. The heat transfer surface was a horizontal, gold-plated, copper disc.

Stability analysis was employed to demonstrate why previous investigators have had only limited success in collecting data in the transition region and to provide a valid basis for equipment designed to operate in this region.

A method of predicting the transition region boiling curve from the nucleate curve and the Liedenfrost point is presented. The method was found to predict the transition boiling of Normal Pentane, Freon 12, …

A Study Of Exothermic Chemical Reaction In A Porous Catalyst Wedge, Joseph Michael Schardl Jr.

Doctoral Dissertations

"Temperature and composition were measured at various locations in a system where ethylene is hydrogenated to ethane on a 1/4 inch porous catalyst wedge made of nickel supported on alumina. 'When the wedge of catalyst was bathed in hydrogen, experimental results indicated a high temperature rise from the feed temperature to the catalyst which is implied by the diffusion controlled regime for solid catalyzed, highly exothermic reactions. This high activity was reversibly reduced by bathing the catalyst wedge in nitrogen for extended time periods (greater than 24 hours). This nitrogen soaking changed the experimental conditions from those of diffusion controlled …

Nucleate Boiling Of N-Pentane, N-Hexane And Several Mixtures Of The Two From Various Tube Arrays, Kenneth Wayne Wall

Doctoral Dissertations

"An investigation of nucleate boiling heat transfer in saturated pools of Normal Pentane, Normal Hexane and several mixtures of the two was conducted. The fluids were boiled from gold-plated, copper, cylindrical heat transfer surfaces, 4.96 inches long, and 1.048 inch in diameter. The heat transfer elements were boiled in varying vertical tube arrays at a pressure of 14.70 psia.

It was found that the mixtures boiled with a lower heat transfer coefficient than that for either pure component when boiled alone. When boiling in any of the tube bundle arrangements, the heat transfer coefficients for the upper tubes in the …

In Vitro Studies Of Lipid Uptake By Medical Grade Silicone Rubbers Used For Heart Valve Balls, Shu Hua Wu

Doctoral Dissertations

"Various chemical and physical aspects of high lipid absorption by medical grade silicone rubber and the dynamic mechanical properties of lipid-rubber systems were studied in order to provide an insight into the problem of 'variance' of these materials when subjected to 'in vitro' and 'in vivo' environments. Wide variations of post cure procedures of the silicone rubber were studied. Different post cures did not appreciably affect the mechanical properties of the silicone rubber. Mass transfer studies demonstrated that the diffusion of linolenic acid into a silicone rubber slab is a purely physical diffusion process (D = 3.2 x 10^{-3 …}

Anionic Polymerization Of A Series Of Cyclocarbosiloxanes, William W. Knickmeyer

Doctoral Dissertations

"A study has been made on the anionic polymerization of a series of cyclocarbosiloxanes of the type: [IMAGE] where n was varied from 2 to 8. The polymerization reaction in benzene, was initiated using cesium trihexyl silanolate, a unique organic soluble liquid catalysts. Benzene served as both a solvent and to shift the position of the NMR SiCH₃ polymer peak away from the monomer peak making it feasible to follow the kinetics on a Varian EM-360 Nuclear Magnetic Resonance Spectrometer. Hexamethylphosphoramide (HMPA) was used as a promoter to solvate the initiator ions and thus increasing the polymerization rate. It …

Mathematical Simulation Of Gas And Water Coning In Petroleum Reservoirs By The Dynamic Material Balance Technique, Visheshwar Nath Simlote

Doctoral Dissertations

"The prediction of coning behavior at a producing oil well is one of the most difficult numerical simulation problems. Because of the convergent flow patterns and small sizes of the inner grid blocks, the radial coordinate models used to study the problem have a tendency to become unstable. Since several hundred pore volumes may flow through the inner grid blocks during a rather small time interval, instabilities are likely to occur in the saturation calculations for these grid blocks. The dynamic approach to saturation calculations is a method which first computes the correct material balance and then calculates the saturation …

Hydrodynamic Mixing Model Applied To A Continuous Stirred-Tank Reactor With And Without Second-Order Reaction, Leon L. Otte

Doctoral Dissertations

Paper 1: "A hydrodynamic mixing (HDM) model, used to calculate the steady-state spatial distribution of conversion for a second-order reaction in a continuous stirred-tank reactor (CSTR) for non-premixed reactants was developed and contrasted with other methods. The HDM model is based on a segmental description of the reactor and includes turbulent mixing effects in each segment. As a test of the model, the experimental results obtained from a tubular reactor were found to be very well represented for a range of reactant ratios. Spatial distributions of concentration and segregation intensity (degree of mixing) within the CSTR were determined for a …