Engineering Commons^™

Degradation Of Dichloromethane, Trichloromethane & Carbon Tetrachloride In A Photoreactor, Sanjay Wadhwa

Theses

A SS 304 photoreactor has been designed to study the degradation of EPA priority pollutants. This newly designed system was used to study the kinetics of degradation of dichloromethane, trichloromethane and carbon tetrachloride under O₂/UV, O₃/O₂/UV and H₂O₂/UV schemes. These compounds have been found to exhibit similar kinetics. The experimental data obtained was. analyzed for pollutant concentration using gas chromatography. The rate constants and mass transfer coefficients were found using a mathematical model to fit the experimental data. A computer program based on the Rosenbrock Hillclimb method in conjunction with …

Energy Considerations In Stock Preparation Refining Modified By Recycling, Rajendra D. Deshpande

Masters Theses

Experiments were conducted to study the effect of refining on virgin fibers as well as on recycled fibers. Interaction effects of recycling and type of treatment of virgin fibers on characteristics of secondary fiber were studied. A significant reduction in drainage properties of the furnish for both hardwood and softwood pulps were observed. This reduction in properties was found proportional to the amount of refining. It is necessary to achieve required strength properties at higher freeness values, if fibers are to be recycled. This can be done by improvement in uniformity or homogeneity of refining and by gentler and less …

Gas-Phase Reactions Of Methylene Chloride And Methylene Chloride-Trichloroethylene Mixture With Methane In Tubular Flow Reactor And Atmospheric Pressure, Javad Tavakoli-Attar

Dissertations

Reactions of methylene chloride diluted in methane and Argon and a mixture of methylene chloride + trichloroethylene diluted in methane and argon are studied in three flow reactors of different surface to volume ratios 4, 10.5, and 16 mm ID , atmospheric pressure and over a temperature range of 750-1000 °C. Experiments were conducted isothermally, ±5 °C over central 80% of oven length using a three zone oven. Argon was added as a diluent in order to limit carbon (s) formation. The concentration ratios of methylene chloride/methane/argon and methylene chloride/trichloroethylene/methane/argon was held constant at 1:4:10 and 1:1:40:40 respectively, throughout the …

Formation Of Light Hydrocarbons And Soot In The Pyrolysis Reactions Of Chloro, Dichlorobenzene, Acetylene And Benzene In An Atmosphere Of Hydrogen, Larry Jiyuan Zhu

Theses

The kinetics of thermal decomposition of chlorobenzene and dichlorobenzene in a hydrogen and helium atmosphere were further studied to investigate formation of soot and light hydrocarbons. The experiments were performed at atmosphere pressure with residence times rangeing from 0.2 to 1.2 seconds, and the temperature ranges of 850°C to 925°C for chlorobenzene and 870°C to 910°C for dichlorobenzene. Flame ionization detectors, which were connected to GC columns, were utilized for the qualitative and quantitative analysis of the reaction products. A methyl silicone capillary column was used analyzing of heavy aromatics and a Carbosive G was used to analyze light hydrocarbons. …

High-Energy, Curable Polycyclopentadiene Binder For Solid Rocket Propellants, Jian Guo Ning

Theses

Diels Alder polymerization of cyclopentadiene ( CPD ) has been carried out at 170°C under inert atmosphere. The resulted polymer has a low bulk viscosity, 7.4 cps, and a number average molecular weight M_n up to 3000. This liquid Prepolymer is curable with maleic anhydride. With ammonium perchlorate, aluminum, and maleic anhydride, a high energy solid propellant has been formulated with this polymer. Via bomb calorimeter, Instron, and density measurement, it was found that this propellant has a better heat of combustion, tensile strength, and solid loading than that of the commercial rocket propellant based on hydroxyl terminated polybutadiene.

A Study On The Poly(Ethylene Terephthalate)/Flouropolymer Blends, Chyan-Nin Chiu

Theses

The rate of crystallization of Polyethylene terephthalate) (PET) can be improved by blending it with polyethylene co chlorotrifluoroethylene) (ECTFE; tradename Halar) so that it can be suitable for injection molding. The special advantage of this method is that molecular weight of the blend will not decrease so much as by adding nucleating agents. That is to say, the mechanical strength of the blend will not decrease very much compared with that of virgin PET.

Oxidation Of Toluene, Benzene And P-Xylene In A Photoreactor, Shiey-Shiun Horng

Theses

A new photoreactor was designed with stainless steel to oxidize refractory chemicals found on the EPA priority list. This new system was investigated by conducting experiments with three three model compounds, namely, toluene benzene and p-xylene. While toluene and benzene reactions are similar, they are faster with UV/ozone than UV/H₂O₂ and p-xylene reacts even faster with UV/ozone than UV/H₂O₂. The experimental data obtained were analyzed by GC and used to interpret the reaction kinetics from proposed models. The rate constants and mass transfer coefficients were found by using the Rosenbsrock Hillclimb optimization algorithm. …

The Effects Of Low Doses (1 To 500 Kilograys) Of 100-Kev Electrons On Four Polymers, Cynthia Anne Bradbury

Physics Theses & Dissertations

Commercial films of polyetherimide (PEI), polyetheretherimide (PEEI), polyethylene terephthalate (PET), and polycarbonate (PC) were exposed in vacuum to l 00-keV electron radiation to total absorbed doses of l, l 0, l 00, 300, and 500 kilograys. The concentration of radiation-generated radicals, as measured by electron paramagnetic resonance (EPR), increased by over an order of magnitude in all four polymers. Correspondingly, the intensity of the infrared absorption peaks increased uniformly for all doses. Solubility tests resulted in decreased solubility in all polymers. IR, EPR, and solubility suggest dehydrogenation of the aliphatic C-H and phenyl C-H sites. The data indicated that cross …

Application Of Mechanical Vapour Recompression To Industrial Slides Drying, Allan Issangya

Tanzania Journal of Engineering and Technology (TJET)

A positive result of the oil crisis of the seventies is the realisation of energy’s value and the need to use it sparingly. Increasing attention has been focussed on all aspects of industry where fuel oil and gas had played a major role.

Industrial drying, one of the most widely applied unit operations in chemical and process engineering, is a highly energy intensive operation. Studies have identified a number of alternatives for lowering energy consumption in this process through various heat recovery techniques.

Due to the difference in their operating principles steam-heated dryers and air-heated dryers, in most aspects, require …

Computer Model For Baker’S Yeast Production, A. K. Temu

Tanzania Journal of Engineering and Technology (TJET)

This paper concerns modelling of fermentation for bakers’ yeast (Saccharomyces Cerevisiae) production using sugar cane blackstrap molasses as a feed. The problem constitutes of expressing physical phenomena, mathematically, as function of operating conditions.

The program developed is easy to run and does not cost much in terms of preparations. With this program different operating conditions were tested and results show that available equations are not exhaustive. Thus more research is recommended.

Reactor Design For Hazardous Waste Treatment Using A White Rot Fungus, Daewon Pak

Dissertations

Various nutrient media and reactor configurations have been explored in order to grow the white rot fungus Phanerochaete chrysosporium, induce its active enzyme, develop kinetic data for the degradation of 2-chlorophenol, and use chemical engineering analysis to design an efficient reactor.

Preliminary experiments indicated that the biodegradation rate was improved by two to three orders of magnitude when the fungus was immobilized. As a result, emphasis shifted to two types of reactor design: a packed-bed reactor employing a silica-based porous support, and a fluidized-bed reactor employing alginate beads. Both were very effective in degrading 2 chlorophenol at inlet concentrations up …

Wastewater Treatment : Phenol Extraction By Liquid Membrane, Jan-Ming Hou

Theses

Two models for the extraction of phenol by means of liquid surfactant membranes is presented in which external mass transfer around w/o emulsion drop, phase and chemical equilibria are taken into account.

The nonlinear coupled P.D.E.'s is solved under assumptions to get a close-formed analytical approximate solution. The experimental results on the batch extraction of phenol are found to be satisfactory simulated by one of the proposed models provided that phenol concentration is higher than 0.01N. The model requires no adjustable parameter thus it can predict the extraction behavior without doing experiments.

Recycled Plastics As Fillers In Polymer Cement Concrete Composites, Shian-Jong Liu

Theses

How to handle the plastic waste is a big task for the modern society in environmental protection. People already focus on it, especially in PET soft drink bottles. Although PET bottle can be reclaimed, its usages are restricted due to the limitation in color and difficulty in purification.

On the other side, concrete is the most common material for human beings to used [sic] in construction. Concrete has good compressive strength, but poor [sic] in flexural and tensile strengths, which limits its applications. So, scientists try to improve its properties by adding the polymer into the conventional concrete, to enhance …

Use Of Recirculation Reactor To Study Biodegradation Of 2-Chlorophenol, Kai-Chung Yang

Theses

The performance of immobilized cells in the treatment of hazardous waste was investigated using a recirculation flow reactor run in a batch mode. A mixed microbial population from a municipal wastewater treatment plant was immobilized in calcium alginate gel. The bio-oxidation ability of these microbes towards a model toxin (2-chlorophenol) was studied. The process parameters studied were as follows:

1. Flow rate of the recycle stream;
2. Biomass loading;
3. Spiking concentration of 2-chlorophenol;
4. Use of buffered vs. non-buffered defined medium.

Dissolved oxygen concentration was monitored using a flow Clark-type dissolved oxygen probe. Oxygen consumption was correlated with the biodegradation of 2-chlorophenol. Physical …

Determination Of Polycyclic Aromatic Hydrocarbons From Incineration Emission Samples, Robert Cebula

Theses

Stack emissions from five sources (one pulverized coal combustion operation, three sewage sludge incineration operations and one gray tin refractory operation) were sampled by use of U.S. EPA Modified Method 5 isokinetic sampling unit for vapor and particulate effluent. The sampling unit provided XAD-2 resin samples, polytetrafluoroethylene and glass fiber filters and impinger washings of dichloromethane. The resins were soxhlet extracted using dichloromethane (DCM) and the filters were soxhlet extracted using DCM followed by acetone. Fractionation of extracts was accomplished by thin layer chromatography. The resulting fractions were analyzed for polycyclic aromatic hydrocarbons (PAH), nitro-PAH and quinone-PAH by high-performance liquid …

Bead Design For Biodegradation Of 2-Chlorophenol Using Microorganisms Entrapped In Alginate Gel, Fayaz Lakhwala

Theses

The performance of immobilized cell reactors varies with a number of parameters, one of which is proper bead design. A mixed microbial population from a waste water treatment plant was immobilized in calcium alginate gel. The viability of these organisms was studied in a microassay reactor by varying parameters such as concentration of calcium chloride, concentration of sodium alginate, temperature of operation, biomass concentration within the beads and concentration of a model compound (2-chlorophenol). The effect of storage on viability over a period of three months was also investigated. It was found possible to have access to active biomass by …

Synergistic Fillers In Polymer Concrete : New Composites, Syed Hassan Javed

Theses

The objective of this study was to examine the effects of synergistic fillers on underwater construction, burning and mechanical properties of polymer portland cement concrete(PPCC).

Fine grains of hydrous calcium sulfate, Trihydrated alumina, Calcium carbonate and fibrous unhydrous calcium sulfate were examined in PPCC. It has been observed that these synergistic filler improves the mechanical property (stress) and reduce the average time of burning of PPCC. With fixed quantity of polymer, the deterioration of PPCC in water increases by replacing the sand with above stated fillers.

A Dynamic Model Of A Fill-And-Draw Reactor And Its Implications For Hazardous Waste Treatment, Shing-Hwa Chang

Theses

A dynamic model of a fill-and-draw reactor has been developed, which includes a number of operational parameters such as the draw-down volume, the fraction of total cycle time devoted to fill, reaction, and draw, and the concentration of the toxic substance in the feed to the reactor. The model has been solved numerically for two cases, one assuming Monod kinetics, and one considering substrate inhibition (Andrews kinetics).

The conversions achieved with this type of reactor have been compared to that of a conventional activated sludge (CSTR) design. These results indicate that for most practical settings of the operating parameters, the …

Biosynthesis Of Amine Oxides Using Calcium-Alginate Immobilized Hog Liver Microsomes : An Evaluation Of Process And Reactor Design, Ioannis I. Valvis

Theses

An evaluation of the biocatalytic ability and the potential utilization of Calcium-alginate immobilized hepatic microsomes (beads) for the biosynthesis of amine oxides has been performed, To accomplish this task, the following three areas Were investigated: immobilization, catalytic biooxidation ability, and reactor configurations.

Immobilization was found to result in higher yields over free microsomes at the expense of higher cofactor requirements. Refrigerated drying of immobilized micro-somes appears to be a better storage technique than wet storage in buffer. Smaller beads resulted in higher rates than larger beads, but size did not affect the overall yield.

Chlorpromazine (CPZ), diphenylamine (DPA) and 4-hydroxy-2,2,6,6-tetramethylpiperidine …

A Field Perspective On Groundwater Contamination, John A. Cherry

Maine Collection

A Field Perspective on Groundwater Contamination

Geological Society of Maine Distinguished Lecturer John Cherry, University of Waterloo, Ontario, sponsored by the Department of Geosciences, University of Southern Maine, 19th May 1988.

Contents: Lecture 1 : Contaminant Migration Processes Illustrated by Field Experiments / Lecture 2 : Behavior of Dense Non-Aqueous Phase Liquids, Illustrated by Lab Experiments and Conceptual Examples / Lecture 3 : Field Case Histories on Groundwater Contamination / Lecture 4 : Hydrogeological Concepts and Criteria for Waste Disposal / Waterloo Center for Groundwater Research Publications List

Synthesis And Characterization Of A Novel Blocked Isocyanate Dental Adhesive Based On Diphenylmethane - 4, 4' - Diisocyanate, Yangming Lin

Theses

The dental adhesive monomers based on diphenylmethane - 4,4 - diisocyanate (MDI) were prepared and studied in this research. The diisocyanate, MDI, was first reacted with hydroxyethyl methacrylate (HEMA) to form an intermediate adduct. This adduct had an active isocyanate end group. It was then bonded with o-chlorophenol (OCP), a blocking agent, to produce a blocked isocyanate monomer.

The new blocked isocyanate (HEMA-MDI-OCP) was found to have an average value of more than 1200 psi in tensile tests measuring its adhesion to dentin slices.

Programming For The Prediction Of Thermodynamic Phenomena, One Kwon Rim

Theses

A Thermodynamic Calculation Program was developed. The program contains the calculation procedure for VAPOR/LIQUID EQUILIBRIUM(Isothermal P-X data and T-X data), HEAT-OF-MIXING(liquid mixture data) and LIQUID/LIQUID EQUILIBRIUM SEPARATION data. The program may optionally use the Knox Molecular(GAM), UNIQUAC, NRTL, Wilson and Redlich-Kister equations, and is prepared to accept any kind of model which will be developed in the future. This program also performs parameter file creation, parameter input, updating of parameters, and is structured to allow implementation of data regression when program is updated. Comparison and analysis of each function were executed using this program. It was revealed that VLE(Vapor-Liquid Equilibrium) …

Hydrodechlorination Reactions Of Trichloroethylene And 1,1 1, Trichloroethane Over Alumina Supported Palladium Catalysts, And, Trichloroethylene Over Nickel Catalyst, Atul R. Shah

Theses

The primary objective of this study was to evaluate the viability for conversion of chlorocarbon wastes solvents into useful hydrocarbons and HCl by catalytic reduction. The second objective was to investigate the pathways for these hydrodechlorination reactions over the chosen alumina supported Palladium and nickel catalysts as well as determine selectivities, product distribution, and deactivation mechanism.

Reactions of trichloroethylene with hydrogen over alumina supported palladium catalyst was studied in temperature range 40°C to 57°C at one atmosphere total pressure. The major products observed were ethane and (cis) 1,2 dichloroethylene with trace products chloroethylene, chloroethane and (trans) 1,2 dichloroethylene. At the …

Periodic Solutions For Three Sedimenting Spheres, Ashok S. Sangani, Russel E. Caflisch, Chjan Lim, Jonathan H. C. Luke

Biomedical and Chemical Engineering - All Scholarship

Exact periodic solutions are found for the relative motion of three spheres sedimenting in a Stokes fluid. Nearby solutions are found to be nearly periodic for a long time. Existence of the exact periodic solutions is proved using the point-particle approximation and symmetry properties of Stokes equations. Numerical simulations for finitie-sized particles are performed using a method of multipole expansions.

Transport Processes In Random Arrays Of Cylinders. Ii. Viscous Flow, Ashok S. Sangani, C. Yao

Biomedical and Chemical Engineering - All Scholarship

A numerical method is developed that takes into account the many-particle interactions in a rigorous manner to determine the effective thermal conductivity Km of a composite medium consisting of parallel circular cylinders of thermal conductivity ak suspended in a matrix of conductivity k. Numerical results for Km are presented for a wide range of a and o, the area fraction of the cylinders, after averaging over several computer-generated random arrays of cylinders. The results obtained via this exact method are compared with those of various approximate analytical methods to assess their utility in predicting Km.

Transport Processes In Random Arrays Of Cylinders. I. Thermal Conduction, Ashok S. Sangani, C. Yao

Biomedical and Chemical Engineering - All Scholarship

A numerical method is developed that takes into account the many particle interactions in a rigorous manner to determine the effective thermal conductivity of Km of a composite medium consisting of parallel circular cylinders of thermal conductivity ak suspended in a matrix of conductivity k. Numerical results for Km are presented for a wide rane of a and o, the area fraction of the cylinders, after averaging over several computer-generated random arrays of cylinders. The results obtained via this exact method are compared with those of various approximate analystical methods to assess their utility in predicting Km.

Improved Streamline-Generating Technique That Uses The Boundary (Integral) Element Method, Daopu Thompson Numbere, D. Tiab

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The boundary element method (BEM) has been used to generate streamlines for homogeneous and sectionally homogeneous reservoirs having irregular boundaries. This technique is superior to earlier methods that use 'image wells' to simulate the reservoir boundary, especially for cases where the reservoir boundary is irregularly shaped. It has wider applicability to different kinds of reservoirs and eliminates the need for trial-and-error solutions. The errors caused by discretization and numerical approximation arise on and adjacent to the boundaries only, therefore the pressures and pressure gradients on which the streamlines are derived can be calculated with very high accuracy in the interior …

Paraffin Deposition Property Measurement Using Differential Scanning Calorimetry, Kevin Lynn Thornsberry

Masters Theses

Differential Scanning Calorimetry (DSC) has been used in past studies to identify the cloud points of diesel fuels, lube oils, jet fuels etc. and it has been assumed that its application extends to all paraffinic hydrocarbons. To verify this and to investigate the possible application of Differential Scanning Calorimetry to the production phase of the petroleum industry, the onset of wax crystallization is compared with ASTM cloud point for a number of paraffinic mixtures including a variety of crude oils. Results show cloud point can be determined for crudes using DSC. Additionally, wax content can be found on a known …

Vle For 1,3-Butadiene With 1,2-Butadiene And Propyne, Patrick J. Gripka

Masters Theses

"Vapor pressures for pure 1,3-butadiene, 1,2-butadiene and propyne and 10 binary mixtures are reported at 5, 20, 35, 50, and 65°C. An equation of state utilizing saturated vapor and liquid densities is used to correlate the experimental data. Calculated relative volatilities and saturated densities are reported for the systems 1,3-butadiene - 1,2-butadiene and 1,3-butadiene - propyne. The thermodynamic excess functions Helmholtz free energy, Gibbs free energy, entropy, enthalpy, internal energy, volume, and heat capacity are derived for the equation of state and the excess properties are reported for the two systems"--Abstract, p. iv.

An Experimental Study Of Adsorption And Variable Temperature Desorption Of Ethanol-Water, Propane-Propylene And Hydrogen Sulfide-Carbon Dioxide-Propane, Suvit Kulvaranon

Masters Theses

"An ideal adsorption only removes the desired components. Many times one or more other components are also adsorbed. If two or more components are adsorbed, an adsorption separation may not be satisfactory or may require additional separation procedures, even though one is highly preferentially adsorbed. In such cases it may be possible to get additional separation during the desorption stage by using variable temperature desorption.

To study such problems, two experimental apparatus were set up, one for adsorption for ethanol and water mixtures on activated carbon and silicalite, the other for propane-propylene mixtures, and hydrogen sulfide-carbon dioxide-propane mixtures both on …