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Development of high temperature catalytic membrane reactors. Final report

Description: Early efforts in 1992 were focused on relocating the membrane reactor system from Alcoa Separation Technology, Inc.`s Warrendale, PA facility to laboratory space at the University of Pittsburgh Applied Research Center (UPARC) in Harmarville, PA following the divestiture of Alcoa Separations to US Filter, Inc. Reconstruction was completed in March, 1992, at which time the reactor was returned to ethylbenzene dehydrogenation service. Efforts on ethylbenzene dehydrogenation to styrene focused on optimizing hybrid reactor performance relative to packed bed operation. Following this, the reactor system was converted to isobutane dehydrogenation. Experimentation on isobutane dehydrogenation focused on design of an inert reactor, evaluation of commercial light alkane dehydrogenation catalysts, and modeling of membrane reactor performance relative to the performance of a packed bed reactor. This report summarizes the effort in 1992 on the development of ceramic membranes as dehydrogenation reactors. In addition, outside interactions on behalf of this investigation are discussed.
Date: February 28, 1992
Creator: Gallaher, G.; Gerdes, T. & Gregg, R.
Partner: UNT Libraries Government Documents Department

Pressure effects on bubble-column flow characteristics

Description: Bubble-column reactors are used in the chemical processing industry for two-phase and three-phase chemical reactions. Hydrodynamic effects must be considered when attempting to scale these reactors to sizes of industrial interest, and diagnostics are needed to acquire data for the validation of multiphase scaling predictions. This paper discusses the use of differential pressure (DP) and gamma- densitometry tomography (GDT) measurements to ascertain the gas distribution in a two-phase bubble column reactor. Tests were performed on an industrial scale reactor (3-m tall, 0.48-m inside diameter) using a 5-Curie cesium-137 source with a sodium-iodide scintillation detector. GDT results provide information on the time- averaged cross-sectional distribution of gas in the liquid, and DP measurements provide information on the time and volume averaged axial distribution of gas. Close agreement was observed between the two methods of measuring the gas distribution in the bubble column. The results clearly show that, for a fixed volumetric flowrate through the reactor, increasing the system pressure leads to an increase in the gas volume fraction or ``gas holdup`` in the liquid. It is also shown from this work that GDT can provide useful diagnostic information on industrial scale bubble-column reactors.
Date: March 1, 1996
Creator: Adkins, D.R.; Shollenberger, K.A.; O`Hern, T.J. & Torczynski, J.R.
Partner: UNT Libraries Government Documents Department

Proceedings of the Workshop on Hydrocarbon Processing Mixing and Scale-Up Problems

Description: A workshop was convened by the Division of Fossil Fuel Utilization of the US Department of Energy in cooperation with the Particulate and Multiphase Process Program of the National Science Foundation to identify needs for fundamental engineering support for the design of chemical reactors for processing heavy hydrocarbon liquids. The problems associated with dispersing liquid hydrocarbons in a reacting gas and mixing within the gas phase are of primary concern. The transactions of the workshop begin with an introduction to the immediate goals of the Department of Energy. Fuel cell systems and current research and development are reviewed. Modeling of combustion and the problems of soot formation and deposits in hydrocarbon fuels are next considered. The fluid mechanics of turbulent mixing and its effect on chemical reactions are then presented. Current experimental work and process development provide an update on the present state-of-the-art.
Date: December 1978
Creator: Gabor, J. D.
Partner: UNT Libraries Government Documents Department

Enhancement of Equilibriumshift in Dehydrogenation Reactions Using a Novel Membrane Reactor

Description: Electroless deposition of palladium thin-films on a surface of microporous ceramic substrate has been used to develop a new class of perm-selective inorganic membrane. In the last report, we presented a numerical method to analyze the stability in single-stage gas permeation. In this reporting period, we present our modeling work on dehydrogenation of cyclohexane in Pd-Ceramic membrane reactor. A model for studying dehydrogenation of cyclohexane in a membrane reactor is developed. Radial diffusion is considered to account for the concentration gradient in radial direction due permeation through the membrane. The model equations are derived for systems with reaction and without reaction. In the non-reaction case, a mixture of argon, benzene, cyclohexane, and hydrogen is used in the reaction side and argon is used as sweep gas in the separation side. Currently, we are working on the details of numerical solution of the model equations.
Date: September 29, 1998
Creator: Ilias, Shamsuddin & King, Franklin G.
Partner: UNT Libraries Government Documents Department

Memorandum on Chemical Reactors and Reactor Hazards

Description: Two important problems in the investigation of reactor hazards are the chemical reactivity of various materials employed in reactor construction and the chracteristics of heat transfer under transient conditions, specifically heat transfer when driven by an exponentially increasing heat source (exp t/T). Although these problems are independent of each other, when studied in relation to reactor hazards they may occur in a closely coupled sequence. For example the onset of a dangerous chemical reactor may be due to structural failure of various reactor components under an exponentially rising heat source originating with a runaway nuclear reactor. For this reason, these two problems should eventually be studied together after an exploratory experimental survey has been made in which they are considered separately.
Date: July 5, 1951
Creator: Mills, M.M.; Pearlman, H.; Ruebsamen, W. & Steele, G., Chrisney, J.
Partner: UNT Libraries Government Documents Department

Scale-Up and Demonstration of Fly Ash Ozonation Technology

Description: This is the fourth quarterly report under DOE Cooperative Agreement No.: DE-FC26-03NT41730. Due a number of circumstances, mostly associated with subcontractor agreements, the actual beginning of the project was delayed from its original award date of March 5, 2003. DOE's Project Manager was kept informed (verbally) by PPL's Project Manager throughout this period. Because of this delay, this is the fourth quarterly report and it refers to the time period from January to March 2004. The on-site deployment and testing of the ozonation system took place during this period. This report summarizes these activities including some preliminary results. No significant issues or concerns are identified.
Date: March 31, 2005
Creator: LaBuz, Larry & Afonso, Rui
Partner: UNT Libraries Government Documents Department

Development and Testing of a High Capacity Plasma Chemical Reactor in the Ukraine

Description: This project, Development and Testing of a High Capacity Plasma Chemical Reactor in the Ukraine was established at the Kharkiv Institute of Physics and Technology (KIPT). The associated CRADA was established with Campbell Applied Physics (CAP) located in El Dorado Hills, California. This project extends an earlier project involving both CAP and KIPT conducted under a separate CRADA. The initial project developed the basic Plasma Chemical Reactor (PCR) for generation of ozone gas. This project built upon the technology developed in the first project, greatly enhancing the output of the PCR while also improving reliability and system control.
Date: July 30, 2012
Creator: Reilly, Raymond W.
Partner: UNT Libraries Government Documents Department

Sandia support for PETC Fischer-Tropsch research: Experimental characterization of slurry-phase bubble-column reactor hydrodynamics

Description: Sandia`s program to develop, implement, and apply diagnostics for hydrodynamic characterization of slurry bubble-column reactors (SBCRs) at industrially relevant conditions is discussed. Gas-liquid flow experiments are performed in an industrial-scale 48 cm ID stainless steel vessel. Gamma-densitometry tomography (GDT) is applied to make spatially resolved gas holdup measurements. Both water and Drakeol 10 with air sparging are examined at ambient and elevated pressures. Gas holdup increases with gas superficial velocity and pressure, and the GDT values are in good agreement with values from differential pressure measurements. Other diagnostic techniques are also discussed.
Date: June 1, 1996
Creator: Jackson, N.B.; Torczynski, J.R.; Shollenberger, K.A.; O`Hern, T.J. & Adkins, D.R.
Partner: UNT Libraries Government Documents Department

Computational Chemistry and Reaction Engineering Workbench

Description: The chemical process industries are among the most energy intensive in the US. While much of the energy use cannot be avoided, (e.g., feedstock energy or separations costs), there are tremendous gains to be had through simulation-based optimizations. The heart of any chemical operation is the chemical reactor and it is here that gains can be made either directly (e.g., reduced heat flux) or indirectly (e.g., reduced downstream separations cost due to more efficient reactor design). The objective of this project was to develop an integrated suite of software to facilitate the simulation and optimization of chemical reactors. In the phase of the project supported by this grant, we focused specifically on gas-phase chemical processes such as combustion and pyrolysis.
Date: December 19, 2003
Creator: Mckinnon, J. Thomas
Partner: UNT Libraries Government Documents Department


Description: The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large diameter reactors.
Date: January 1, 2002
Creator: Toseland, Bernard A.
Partner: UNT Libraries Government Documents Department

Effect of reactor design on the plasma treatment of NO<sub>x</sub>

Description: This paper presents the results of experiments in which various parameters were varied systematically in an attempt to understand how the reactor design affects the energy efficiency for plasma processing of NO <sub>x</sub> . These parameters include the packing material, electrode diameter, and voltage frequency. It is shown that the applied voltage is not the relevant parameter when comparing the performance of different plasma reactors. The important control parameter is the input energy density. In accordance with the observations reported by Penetrante et al. [<i>Applied Physics Letters</i> <b>68</b>, 3719-3721 (1996)], we have found that reactor design has little influence on the basic energy consumption of the plasma. Consequently, different reactor designs should yield basically the same plasma chemistry if the experiments are performed under identical gas composition and temperature conditions.
Date: August 24, 1998
Creator: McLarnon, C R & Penetrante, B M
Partner: UNT Libraries Government Documents Department

Photochemical coal dissolution. Final technical progress report, September 30, 1993--September 29, 1996

Description: A flowing solvent photochemical reactor was designed, built and tested. A modified ACE photochemical reactor, lamp and power supply were employed. They were modified to accommodate a silica column-constrained dispersed coal sample and a solvent flowing through the silica/coal column to sweep away coal extract. Before each experiment the column was packed with the mixture of silica and coal in the annular space around the lamp. A reflective aluminum surface (foil) reflected any light-transmitted through the column for multiple passes back through the sample. A variable speed Rainin Rabbit Plus peristaltic pump was interfaced to an IBM XT computer via a Gilson RS232/RS422 converter. The purpose of the computer control was to vary the speed of the pump so as to control the absorbance of the solution of coal extract in the solvent. Absorbances at a chosen wavelength were measured by a Spec 21 spectrophotometer with a flow cell connected to the column effluent port. A signal proportional to transmittance from the Spec 21 was delivered to the computer through a Keithley DAS 801 A/D plug-in the computer. The analysis of the Spec 21 signal and control of the pump speed was based on a QuickBasic computer program written by us.
Date: May 1, 1997
Creator: Doetschman, D.C.
Partner: UNT Libraries Government Documents Department

Technology development for iron fisher-tropsch catalysis

Description: The goal of the proposed work is the development of iron-based Fischer-Tropsch catalysts that combined high activity, selectivity and life with physical robustness for slurry phase reactors that will produce either low-alpha or high-alpha products. the catalyst that is developed will be suitable for testing at the Advanced Fuels Development Facility at LaPorte, Texas or similar sized plant. Previous work by the offeror has produced a catalyst formulation that is 1.5 times as active as the standard-catalyst developed by German workers for slurry phase synthesis, The proposed work will optimize the catalyst composition and pretreatment operation for this low-alpha catalyst. In parallel, work will be conducted to design a high-alpha iron catalyst that is suitable for slurry phase synthesis. Studies will be conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. the oxidation/reduction cycles that are anticipated to occur in large, commercial reactors will be studies at the laboratory scale. Catalyst performance will be determined for catalysts synthesized in this program for activity, selectivity, and aging characteristics.
Date: July 15, 1997
Creator: Davis, B.H.
Partner: UNT Libraries Government Documents Department

Determination of the Forms of Nitrogen Released in Coal Tar During Rapid Devolatilization. Semi-annual report, May 1-October 31, 1997

Description: The primary objective of this work is to determine the forms of nitrogen in coal that lead to nitrogen release during devolatilization. Experiments are to be performed in two existing laminar flow reactors available at Brigham Young University, which are both capable of temperatures (up to 2000 K), particle heating rates (104 to 105 K/s), and residence times (up to 500 ms) relevant to conditions commonly encountered in industrial pulverized coal combustors. The forms of nitrogen in coal, char, and tar samples are analyzed using state-of-the-art techniques, including nuclear magnetic resonance (NMR), X-Ray photoelectron spectroscopy (XPS), and high resolution nitrogen-specific chromatography. These sophisticated analysis techniques are being performed in collaboration with other researchers at BYU, the University of Utah, and industrial organizations. Coals have been obtained as a function of rank, including eight coals from the University of Utah that are to be used in pilot scale tests in support of the DOE Coal-2000 HIPPS (High Performance Power Systems) and LEBS (Low- Emission Boiler Systems) programs. Anticipated results from the proposed research are (a) nitrogen release parameters during devolatilization for specific coals pertinent to the HIPPS and LEBS projects, (b) better fundamental understanding of the chemistry of nitrogen release, and (c) a nitrogen release submodel based on fundamental chemistry that may be more widely applicable than existing empirical relationships.
Date: October 31, 1997
Creator: Fletcher, T.H., Goldberg, P.
Partner: UNT Libraries Government Documents Department

Long life catalytic membrane reactors for spontaneous conversion of natural gas to synthesis gas

Description: This program is focusing on the development of mixed ionic and electronic conducting materials based on the brown millerite structure for use in catalytic membrane reactors (CMRs). These CMRs are being evaluated for promoting the spontaneous and highly selective oxidative reforming of carbon dioxide / natural gas mixtures to synthesis gas.
Date: October 1, 1997
Creator: Schwartz, M., White, J., Deych, S., Millard, J., Myers, M., Sammells, A.
Partner: UNT Libraries Government Documents Department

Methyl chloride via oxhydrochlorination of methane

Description: Dow Corning is developing a route from methane to methyl chloride via oxyhydrochlorination (OHC) chemistry with joint support from the Gas Research Institute and the Department of Energy Federal Energy Technology Center. Dow Corning is the world`s largest producer of methyl chloride and uses it as an intermediate in the production of silicone materials. Other uses include production of higher hydrocarbons, methyl cellulose, quaternary ammonium salts and herbicides. The objective of this project is to demonstrate and develop a route to methyl chloride with reduced variable cost by using methane instead of methanol raw materials. Methyl chloride is currently produced from methanol, but U.S. demand is typically higher than available domestic supply, resulting in fluctuating prices. OHC technology utilizes domestic natural gas as a feedstock, which allows a lower-cost source of methyl chloride which is independent of methanol. In addition to other uses of methyl chloride, OHC could be a key step in a gas-to-liquid fuels process. These uses could divert significant methanol demand to methane. A stable and selective catalyst has been developed in the laboratory and evaluated in a purpose-built demonstration unit. Materials of construction issues have been resolved and the unit has been run under a range of conditions to evaluate catalyst performance and stability. Many technological advances have been made, especially in the areas of catalyst development, online FTIR analysis of the product stream, and recovery of methyl chloride product via an absorber/stripper system. Significant technological hurdles still remain including heat transfer, catalysts scaleup, orthogonality in modeling, and scaleable absorption data. Economics of the oxyhydrochlorination process have been evaluated an found to be unfavorable due to high capital and utility costs. Future efforts will focus on improved methane conversion at high methyl chloride selectivity.
Date: December 31, 1997
Creator: Jarvis, R.F. Jr.
Partner: UNT Libraries Government Documents Department

Methane coupling by membrane reactor. Quarterly technical progress report, September 25, 1995--December 24, 1995

Description: The performance of the third type of catalytic membrane reactor configuration, with catalyst deposited in the membrane and no catalyst or inert materials in the tube side, was evaluated. The C{sub 2} selectivity obtained was about 10% due to the gas phase reaction in the empty tube side of the reactor. The membrane reactor with an oxygen-permeable dense membrane has been built. The use of a dense membrane will eliminate the loss of hydrocarbon from the tube side to the shell side, as observed in the Vycor glass membrane reactor. Also, air can be used as the oxygen source without contaminating the product. La/MgO was synthesized and will be used as the catalyst for the dense membrane reactor. This catalyst was reported in the literature to show significant improvement of C{sub 2} selectivity and yield for oxidative coupling of methane in a packed-bed reactor by using the operation mode of staged-feed of oxygen. A reactor mode for methane oxidative coupling in reactors with both distributed oxygen feed and C{sub 2} product removal was developed based on the general model of cross-flow reactors reported in the last quarterly report. A distributed oxygen feed could give rise to much higher C{sub 2} yield than the co-feed reactor as long as the space time is long enough. In the case of a two-membrane reactor, where oxygen is supplied by one membrane and products are removed through the other membrane, a high separation factor of C{sub 2} product to methane for the product-removal membrane is critical to achieve high C{sub 2} yield.
Date: March 15, 1996
Partner: UNT Libraries Government Documents Department

A numerical investigation of scale-up effects on coke yields of a thermal cracking Riser reactor

Description: A validated computational fluid dynamics (CFD) computer code, ICRKFLO, was used to investigate the scale-up effects on the coke yields of thermal cracking riser factors. Comparisons were made for calculated coke yields of pilot- and commercial-scales riser units. Computational results show that the riser aspect ratio, reaction temperature, particle residence time, and particle/oil ratio have major impacts on the coke yield. A computational experiment was conducted to determine optimal operating conditions for a conceptual design of a commercial-scale riser unit. This experiment showed that the performance loss in scale-up from pilot to commercial scale may be almost completely recovered through optimizing the operating conditions after scale-up using the CFD simulations as a guide.
Date: May 1, 1995
Creator: Chang, S.L.; Lottes, S.A. & Petrick, M.
Partner: UNT Libraries Government Documents Department

Design Strategies for Optically-Accessible, High-Temperature, High-Pressure Reactor

Description: The authors have developed two optical cell designs for high-pressure and high-temperature fluid research: one for flow systems, and the other for larger batch systems. The flow system design uses spring washers to balance the unequal thermal expansions of the reactor and the window materials. A typical design calculation is presented showing the relationship between system pressure, operating temperature, and torque applied to the window-retaining nut. The second design employs a different strategy more appropriate for larger windows. This design uses two seals: one for the window that benefits from system pressure, and a second one that relies on knife-edge, metal-to-metal contact.
Date: February 1, 2000
Creator: Rice, S. F.; Steeper, R. R.; LaJeunesse, C. A.; Hanush, R. G. & Aiken, J. D.
Partner: UNT Libraries Government Documents Department

Hydrodynamic models for slurry bubble column reactor

Description: The objective of this investigation is to convert learning gas-solid-liquid fluidization model into a predictive design model. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid and particulate phases. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. A paper ``Liquid-Solid Fluidization Using Kinetic Theory'' by D.Gidaspow and L.Huilin was presented at the Chicago ANNUAL AIChE meeting in November 1996. It will be published in the Symposium Series on Fluidization and Fluid Particle Systems. The authors have also computed the particle Reynolds stress for three-phase fluidization. Using an IIT Reflected Light Microscope they have determined the particle size distribution of the Air Products catalyst. The catalyst disintegrated during fluidization. They believe it is necessary to design a better catalyst . This can be done by finding an optimum particle size by considering difision and reaction in the catalyst and mixing resistance to mass transfer in the fluids. Their theory permits them to determine such an optimum particle size and best operating particle concentration.
Date: January 31, 1997
Creator: Gidaspow, Dimitri
Partner: UNT Libraries Government Documents Department

Engineering development of slurry bubble column recactor(SBCR) technology

Description: The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large diameter reactors.
Date: December 1, 1998
Creator: Bernard A. Toseland, Ph.D.
Partner: UNT Libraries Government Documents Department

A numerical investigation of gasoline production from multi-stage FCC systems

Description: Staged, fluid catalytic cracking (FCC) processes are deemed to have the potential to enhance FCC performance in the areas of product selectivity, operating flexibility, throughput, reliability, operating costs, and emissions. Computational fluid dynamic (CFD) codes are used to analyze various staged FCC concepts to help accelerate their development into commercial products. Three conceptual multi-stage FCC systems were evaluated using a validated CFD code. The results indicated potential increases of gasoline production from these conceptual designs.
Date: May 9, 2000
Creator: Chang, S. L.; Zhou, C. Q. & Petrick, M.
Partner: UNT Libraries Government Documents Department