PREFACE :
A WORD TO OUR INDUSTRIAL COLLEAGUES AND PARTNERS
After 33 years of guiding CREL daily efforts Mike Dudukovic took a long overdue sabbatical during the 2007/2008 academic year while CREL affairs remained in capable hands of its co-director Professor Al Dahhan. During this one year sabbatical leave Mike visited numerous universities and companies in China, Hong Kong, Taiwan, Australia, India, Qatar, Serbia, Holland, Germany and Slovakia. He presented invited lectures and examined how chemical reaction engineering is taught and practiced around the world, especially in counties like India and China that are experiencing rapid growth in process industries. The prevailing pattern in the world seems to be to copy the American system, often without sufficient thought whether it truly matches best local needs. While undeniably reaction engineering has contributed greatly to the implementation of many technologies, the level of science used in its implementation is still entirely governed by the profit motive. Hence, when profitable routes can be found with less development effort, they are chosen over the more environmentally benign ones which require more development capital. Thus, in production of fuels and commodity chemicals as well as minerals innovations are slow to come as spruced up old technologies are being licensed in the developing world. More stringent environmental rules and tax incentives for implementation of sustainable more efficient technologies are needed to change this around and offer positive global changes for the environment. The global challenge facing our profession is the need to increase the efficiency and reduce the environmental impact of transferring molecular scale discoveries to the commercial scale. It is also clear that rapid and safe transfer of molecular discoveries to commercial practice with proper considerations of sustainability requires personnel with deep reaction engineering expertise. Thus the body of knowledge that we try to impart to our students at CREL is invaluable world-wide.
Our Chemical Reaction Engineering Laboratory (CREL) has a 33 year tradition in research cooperation with our industrial partners on various aspects of multiphase reaction engineering (MRE). This emphasizes the fact that multiphase reaction engineering (MRE) is the key enabling discipline for transferring of molecular scale discoveries to commercial practice. By advancing the multi-scale reaction engineering methodology we ensure the needed breadth and depth of new generations of reaction engineers. After graduating from CREL-WUSTL our students are well equipped to handle many challenges that relate to clean sustainable technologies, energy or fuels production, environmental and human health concerns. We continue engaging these young people in exciting research and provide them with the depth and breadth needed to handle modern technological advances.
We thank our past CREL sponsors for continuing their support via the MRE program and encourage others to join our unique organization with global reach that facilitates networking between industry and academia. We look forward to seeing you all at CREL on October 8 and 9, 2008 at our annual meeting.
M.P. Dudukovic
Director, CREL
INTRODUCTION
The Chemical Reaction Engineering Laboratory (CREL) at WashingtonUniversity in St. Louis (WUSTL) has a long tradition (over 30 years) as a premier academic research laboratory. CREL advances multiphase reaction engineering methodology, facilitates transfer of new findings to industrial practice, and educates and trains new generations of versatile reaction engineering experts with strong grasp of fundamentals.
The grand challenge facing our profession is the need to provide reliable energy sources and increase the production of manufactured goods in order to improve the living standards throughout the world while reducing the global damage to the environment and increasing the sustainability of our processing practices. This can only be accomplished through education with increased reliance on scientific fundamentals and by a partnership between academia, industry and policy forming bodies.
CREL’s focus on reaction engineering of multiphase systems addresses the transformation of nonrenewable and renewable resources into clean fuels, chemicals, food, feed, pharmaceuticals, and new materials. It is the transformations through reactions (which include chemical, biochemical, electrochemical, biological reactions), that change the structure and property of molecules generating desired products and sometimes producing by side reactions undesirable side products. The choice of reaction chemistry, catalyst, operating conditions and the selection of reactor type and contacting pattern determine the volumetric productivity, yield and selectivity of the process. An overwhelming percentage of reaction systems (over 95%) in practice are heterogeneous in nature, i.e. involve more than one phase. Quantifying reactor performance demands understanding of: 1) molecular scale events, to arrive at mechanistic description of kinetic rates, 2) micro scale (single eddy, single catalyst particle scale) transport-kinetic interactions, and 3) reactor scale flow patterns and phase contacting. Reactor type selection and its performance dictate the number of separation units needed in the process and their load and thus affect profoundly the overall economics of the process. The reactor is also the key to environmentally friendly processing in preventing pollution at the source.
We at the Chemical Reaction Engineering Laboratory (CREL) define reaction engineering as a powerful general methodology that quantifies the interactions between reaction kinetics (chemical, photochemical, electrochemical, biochemical, biological, etc.) and transport phenomena (momentum, mass and heat transfer) at molecular, local and global scales in various reactor types. Such quantification leads to proper understanding of the system and process and to predictive models for reactor design and operation, scale-up/scale-down, troubleshooting and control. We also firmly believe that reaction engineering can only flourish if addressing real industrial problems and to do this effectively a university –industry partnership is needed. For the last 3 decades we have nourished such partnerships.
Being an educational research laboratory, we strive to provide a unique and stimulating environment for our students. We expect them to gain a broad knowledge of reaction engineering principles so that they can effectively use the state-of-the-art reaction engineering in a variety of diverse applications. We also require them to advance the state-of-the-art in their chosen specialty. CREL is a unique organization that strives to provide rapid transfer of academic research to industrial practice and that has developed and maintained close ties with industry. The current industrial participants sponsor CREL research activities under the umbrella of multiphase reaction engineering (MRE) project which encompasses a number of active CREL research projects. The industrial participation in the MRE project remains similar to the previous CREL industrial membership. Hence, the industrial sponsors benefit in many ways: (i) by being informed of the latest advances in reaction engineering, (ii) by jointly establishing research projects and having rapid access to their results (iii) by having access to unique experimental facilities and the best available multiphase flow models, (iv) by being able to use CREL consulting services and fund research contracts at CREL, (v) by accepting qualified students to work on company premises on projects of common interest, (vi) by getting training for industrial personnel and short courses from CREL, (vii) by doing joint research, (viii) by providing input for MRE project long-term research and in selection of MRE future thesis projects and annual statement of work.
Clearly there are many opportunities to leverage resources and work out partnerships with other sponsors and CREL. CREL has always provided means for networking and close interactions with universities, national laboratories and companies from around the world.
The current trends in industry on increasing the efficiency and company profit margins have had many side effects. For example, even the largest companies cannot afford any more to have teams of scientists and engineers maintaining their expertise in general areas, they are forced to specialize. Nor can the companies afford to maintain the facilities and equipment for cold flow modeling, pilot plant scale investigations or rigorous kinetic studies. Yet, the diversity of the business that they pursue and the constant pressure to scale-up new production more rapidly, or improve existing plants; require general expertise and tools for modern scale-up. Moreover, the current changes in the trend of chemical engineering education and the graduate research levels funding allocation affects the industrial needs for well trained and educated students in reaction engineering in an adverse way. CREL offers a unique opportunity to our industrial sponsors for leveraging their resources effectively and produces qualified and well trained engineers. Therefore, we at CREL can be a valuable partner for improved troubleshooting of existing processes and in scale-up of new ones. We also offer breadth and depth in the general methodology of reaction engineering plus unique facilities. In this new business climate association with CREL has become an even more valuable asset to our industrial partners.
KEY RESEARCH AREAS
The following are the key areas in which we offer unique multiphase reaction engineering research projects to our industrial sponsors. Our long-term objective is to establish a unique facility for noninvasive monitoring of multiphase systems and to develop the best possible simulations for reactor modeling based on firm hydrodynamic principles. At the same time, we invent and investigate novel measurement techniques and reactor types for application to energy, environmental, biochemical, chemical, petroleum and materials processing problems.
i)Quantification of flow fields, in gas-liquid, liquid-solid, gas-solid, gas-liquid-solid systems in various reactor types via our unique computer automated radioactive particle tracking (CARPT) and gamma ray computer tomography for measurement of instantaneous velocities, turbulence and back mixing parameters, time averaged circulation patterns voidage (holdup) distribution and other parameters. These data are not available by other means and can be used for scale up, design and model validation. This includes further development of our novel experimental techniques (CARPT-CT) and other tools (optical probes, gas and liquid tracer techniques, heat transfer probes, mass transfer techniques, pressure fluctuation and pressure drop via differential pressure transducers, CCD camera, etc.) for measurement of flow, mixing, density profiles and transport in multiphase systems. No other laboratory in the world has this CARPT-CT combination that provides the capabilities for studying systems with large volume fraction of the dispersed phase i.e. systems that we call opaque. Recently, progress has been made under DOE funding for anaerobic digester (Professor M. Al-Dahhan) to advance CARPT technique from single particle tracking to multi-particle tracking (MP-CARPT) (Vesvikar, 2006) and CT from single γ-ray source to dual γ-ray source (DSCT) (Varma, 2007) where the density distribution of three moving phases can be measured simultaneously.
ii)Quantification of the reaction rate and kinetics, and evaluation and characterization of the existing, new or novel catalysts that are either in use in the existing processes and technologies or are developed for new and/or improved processes and technologies.
iii)Quantification of the impact of integrating the transport (hydrodynamics/momentum, mass and heat) and kinetics (chemistry/biology/electrochemistry) on the processes performance (i.e., conversion, selectivity, efficiency, safety, pollution generation, energy efficiency, etc.). Mini-reactor facilities made from Hastalloy C and titanium for oxidation and aklylation and other reaction processes equipped with IR probe (300 ml and 25 ml autoclave stirred reactors, 5 ml and 50 ml packed beds) have been developed and implemented.
iv)Development of advanced models for various multiphase reactor types (e.g., bubble and slurry columns, trickle beds, packed beds, stirred tanks, risers, fluidized beds, etc.) that can be coupled with client’s proprietary kinetics for improved design, scale up, operation or troubleshooting of commercial and pilot plant reactors. This includes using first principles in the development of hydrodynamic and reactor models, integrating transport, hydrodynamics and kinetics and verifying such models with carefully planned experiments.
v)Validation of CFD codes by CARPT-CT and optical probe measurements in various multiphase reactor types.
vi)Development of environmentally benign process technologies (e.g. clean alternative/renewable fuels and chemicals, hydrocarbon oxidation, solid acid alkylations, hydrogenations, hydroformylation and others).
vii) Development of new concepts and reactor technology for biomass conversion to fuels and chemicals, bio-processing, wastes treatment, carbon dioxide capture, etc. viii) Providing access to our new process concepts and ideas, facilities and expertise for potential joint projects. ix) Inventing and investigating novel reactor types for application to energy, environmental, chemical, fuel, biochemical and material processes.
ACKNOWLEDGEMENT
The continuity of our research on multiphase reaction engineering has been made possible by the Department of Energy (DOE), NSF, USDA and our industrial sponsors. In 2006/2007 they are: ADM, BP, Chevron, ConocoPhillips, DuPont, Eastman, Eni, Exxon-Mobil, IFP, Ineos Nitriles, Johnson Matthey, MEMC, Monsanto Envirochem, Sasol, Shell, Statoil, Syntroleum, Total, and UOP. To them goes our gratitude for having the foresight to support fundamental and applied research in the areas that are vital to their businesses.
MULTIPHASE REACTION ENGINEERING (MRE)
PROJECT PARTICIPATION PLAN
In 2007 the CREL membership has been changed to Multiphase Reaction Engineering project participation through the Chemical Reaction Engineering Laboratory (CREL) at WashingtonUniversity. The previous and the current industrial participation program remain similar. It is a unique entity for industry/academia interactions that pools industrial and governmental resources for needed long-term fundamental research in reaction engineering, conducts such fundamental research and transfers the results to industrial practice and enriches the literature. This provides broad and in depth reaction engineering education and training both to students and industrial practitioners. Also it makes it possible for industrial participants to take a long term view and participate in the development of new ideas, methods and techniques. By pooling industrial resources together with governmental funding for conducting fundamental research in reaction engineering CREL offers unique and attractive opportunities for leveraging of company and government resources. Both systematic long term studies via students' theses and research contracts for sponsors are pursued.
Therefore, the Project on Multiphase Reaction Engineering (MRE) represents an open ended multi-year research commitment to advancing the methodology for quantification, modeling, scale-up and design of multiphase reaction engineering systems. This research is pursued with faculty, research associates (post doctoral candidates), Ph.D. graduate students, and undergraduates when appropriate, with involvement of industrial members.
Key advantages of MRE membership that CREL offers:
●Involvement of world recognized faculty in reaction engineering on advancing the state of the art of multiphase reactor operation and design
●Unique facilities for quantification of phase distributions, flow and mixing in various multi-phase contactors and development of improved fundamentally based multi-phase reactor models
●Validation of CFD codes for multiphase opaque systems
●Multi-scale approach to transfer of molecular discoveries to novel process schemes
●Novel approaches to increased thermal and material efficiency
●Strong basis in gas to liquid fuels, renewable biomass to energy schemes, coal conversion technologies
●Strong basis in silicon manufacture
●General reaction engineering expertise
MRE PARTICIPATION OBJECTIVES
The overall objective for the research activities under the Project on Multiphase Reaction Engineering (MRE) is to advance the fundamental understanding and quantification of multi-scale-transport-kinetic interactions in various multiphase flow systems in order to ensure environmentally benign, energy efficiency and efficient transformation of renewable and non-renewable resources to fuels, chemicals and materials.
To advance this overall objective the CREL faculty identifies critical areas in multiphase reaction engineering related to specific reactor types (e.g. bubble columns, trickle beds, fluidized beds, risers, etc.), specific processes (e.g. alkylation, oxidation, hydrogenation, enzyme reactions, etc.) and/or novel reactors (e.g. catalytic distillation, micro/mini-reactors, etc.) in which methodical application of scientific principles, as advocated by CREL, can have a significant impact on the technology. In addition, industrial members may pass to CREL faculty ideas for needed long term research projects to be considered among the selected topics. These selected topics represent the basis for the sub-projects to be chosen with industrial participants inputs for study. Continuity of the chosen sub-projects is maintained via Ph.D. theses work of graduate students. For the selection of the future sub-projects, the proposals for the new sub-subprojects are circulated to sponsors in summer each year and their feedback is solicited and documented. At the annual CREL meeting (to be held in October each year) the final selection of new sub-projects are made as per budget permitting, from these proposals.
However, the continuity of subprojects in progress supporting Ph.D. students is given priority.
A specific sub-project is selected for direct support from the industrial funds committed to the MRE Project based on intellectual merit, aptitude and capabilities of the available graduate students and interest of the faculty, while accounting for the feedback from participating companies by the process described above. Opportunities for future funding by federal government and industry are also considered in the selection process.
The industrial funds contributed to the MRE Project are used to support the above overall objectives and the objectives below. This includes the support for the personnel working on the specific agreed upon sub-projects, support of viable CREL infrastructure related to the Project, and support of the work that complements studies done with other funding on related topics. Of course, topics of specific interest to a participating company are always funded by a separate research agreement between that company and WUSTL and the terms are negotiated separately from the agreement for the MRE project. All research products remain the intellectual property of CREL.