In this work, a process plant flow sheet that co-produces acetic acid and hydrogen/power from natural gas with zero carbon dioxide emissions is developed. Two cases are explored: the production of acetic acid and hydrogen (case 1) and the production of acetic acid and power (case 2). This is realized by the selection of an appropriate reaction cluster whose sum results in the overall reaction that co-produces acetic acid and hydrogen/power. The concept of energetic self-sufficiency is introduced and it imposes constraints on the system defined in terms of the ratio of oxygen feed to acetic acid produced. Heat and power integration of the converged flowsheet reveals an operating range for each case that guarantees energetic self-sufficiency. Operating points are chosen to conduct a preliminary economic analysis and a carbon dioxide cost and performance metric calculation to quantify profitability and carbon capture potential of the overall process.

This work identifies the global optimum for an infinite number of instances of the Total Annualized Cost (TAC) problem for compressor-intercooler sequences of constant compressibility factor gases with variable heat capacity. The prior state of the art involved the identification of the global optimum for an infinite number of instances of the TAC problem for compressor-intercooler sequences of constant compressibility factor gases with constant heat capacity. The resulting mathematical formulation of the TAC problem involves functions whose evaluation requires integral calculations. The necessary conditions of optimality for the TAC problem are then used to establish a number of mathematical properties, which are then used to establish the foundation of the proposed global optimization procedure. An illustrative case study on methane compression is then presented. Its results suggest that the use of an average (constant) heat capacity over the allowable operating temperature range is a reasonable approximation that yields a global TAC minimum that is within 1% of the true global TAC minimum.

In recent decades, the world has been concerned about the environmental impact of CO2 emissions into the atmosphere. Thus,

researchers have been focusing on enhancing current technologies, such as the Reverse Water Gas Shift (RWGS) reaction, to convert CO2 to synthetic fuels. The goal of this research was to develop a catalyst that has a high CO2 conversion and CO selectivity. To achieve this goal, different experiments were conducted at the same conditions to study the effect of different supports, metal loadings and different metals. All the experimental results were compared to equilibrium data obtained from Aspen Plus. Each tested catalyst was analyzed by BET and XRD to understand its physical and chemical structure as well as its behavior. Best catalyst was identified to be 5 wt% Cu supported on MgO, which achieved 20% CO2 conversion, 84% of Equilibrium CO2 conversion, and 75% CO selectivity.

A zero carbon dioxide emission process is developed, in which electrical power and formic acid are coproduced from coal. The overall reaction for the proposed process uses coal, oxygen, and water as reactants. A reaction cluster is proposed which consists of feasible chemical reactions. These are: gasification of coal to syngas; CO2 hydrogenation to formic acid; hydrogen combustion; and CO combustion. By adjusting the oxygen delivery ratio, the coal gasification is designed to be energetically self-sufficient, so that the whole process produces the largest amount of power. Temperature and heat load information for each process stream is obtained from the software simulation and used in carrying out a heat and power integration study. Through the use of heat engine and heat pump subnetworks, a feasible operating envelope for the considered process is identified. A preliminary technicoeconomic analysis is carried out, which establishes the superiority of the proposed process to current coal power plant technology.

The prevalent common approach among sustainability analysis tools is to examine if some preconceived notions of what is acceptable, i.e., “sustainable”, hold true over a specific period of time. For example, within the commercial context, Life Cycle Analysis (LCA) inspects whether the environmental impacts associated with all stages of a commercial product or process are within an acceptable range. Expanding on this idea, this thesis aims to put forward a new mathematical viewpoint towards sustainability analysis of cases involving dynamical systems. Additionally, the idea of sustainability synthesis of such cases is presented for the first time. To this end, the Sustainability over Sets (SOS) and Sustainizability over Sets (SIZOS) concepts have been introduced as sustainable system analysis and synthesis tools, respectively. These concepts provide rigorous definitions of sustainability with a wide range of applications, and bring forward associated mathematical machinery enabling sustainability analysis of complex multidimensional systems and a methodology for sustainable system synthesis.By defining a system as an assemblage of interrelated components, SOS utilizes the concept of dynamical system theory and the mathematical idea of invariant sets to construct a conceptual framework within which the time evolution of a system can be analyzed and to provide an answer to its sustainability status independent of the examiner. This framework first formalizes the acceptable levels of sustainable behavior as sets in the system’s state space. It then translates the satisfaction of these sustainability criteria over an infinite time to the requirement that the system state trajectories initiated within the set remain within that set forever. To enable this analysis, necessary and sufficient mathematical criteria are first introduced for lumped systems described by autonomous ordinary differential equations (ODEs). Furthermore, these mathematical criteria are expanded to sustainability analysis of systems described by parabolic partial differential equations (PDEs) defined on a bounded and connected domain. Having established the methodology for sustainability analysis, Sustainizability Over Sets (SIZOS) refers to the existence of allowable external actions and/or design changes that can render sustainable over a defined set an unsustainable system. This novel concept provides necessary and sufficient criteria for sustainability synthesis of time variant forced systems. SOS and SIZOS concepts' wide range of applications is demonstrated through various lumped and spatially distributed cases with two to eleven dimensions. These systems exhibit complex behaviors such as oscillation or chaos. One such example is an isothermal biological CSTR, modeled through idealized cell and substrate balance equations and Monod kinetics. SOS analysis identified this system as unsustainable over rectangular sets regardless of its parameter values. Subsequently, this system has been made sustainable by manipulating the reactor's Damkohler number through the allowable change in feed flow rate and concentration. Next, sustainability of a chaotic, tri-trophic food chain, an oscillatory eleven-dimensional food network, and a fire-prone tree-grass system is assessed. Finally, by including the spatial heterogeneity within the tree-grass dynamics, its sustainability status under various wildfire frequencies, and tree grass growth rates has been analyzed. Ultimately, this body of work serves as the foundation for further developing SOS and SIZOS concepts as a whole and presents a guiding approach for their mathematical implementation through various examples.

In this work, a flowsheet to produce urea and hydrogen/power from natural gas has been developed, that generates no carbon dioxide emissions through process integration and appropriate selection of reaction conditions, and stream compositions. Two cases are discussed here: the production of urea and hydrogen (case 1) and the production of urea and power (case 2). The energetic self-sufficiency of the overall reaction is first examined, to determine applicable constraints to the overall process. The realization of this overall reaction through a cluster of technologically feasible reactions is then proposed, and an associated process flowsheet is simulated in UNISIM, consisting of four subsystems, including Steam Methane Reforming (SMR), Gaseous Separation (GS), Ammonia Synthesis (AS), and Urea Synthesis (US). Last, economical analysis of the two considered cases is conducted.

Carbon and NOx emissions have been a major drawback in the industry of air pollution control. Monolith reactors have thrived from their effective use in reducing those air pollutants from both automotive and industrial power plants. This work focuses on the optimization of monolith reactor design by first developing a 3-D mathematical model for an isothermal, rectangular monolith reactor featuring first order irreversible volumetric and surface reactions. Then solving the species mass, continuity, momentum and heat balance equations necessary for each plug flow, fully developed laminar flow and developing fluid flow models, with a known inlet reactant mass fraction/concentration and volumetric flowrate. Finally, a systematic optimization algorithm technique is used depending on the fluid flow considered to optimize the non-convex optimization problem that aims for a maximum conversion subject to capital cost to production ratio and pumping/compression cost to production ratio that determines an upper bound on the fluid velocity. Comparison of results between each fluid flow model developed is discussed in each series.

This dissertation examines input output approaches, including analytical and CFD models, aimed at reactor performance assessment for optimal process design. While analytical models can rapidly provide reactor output metrics by forgoing levels of complexity, they are often limited by many underlying assumptions. Conversely, slow-to-solve CFD models are more versatile in their application due to a reduced number of necessary simplifications. To demonstrate the applicability of both approaches in this work, first, an analytical method has been used to accurately calculate outlet concentrations for laminar flow reactors undergoing a steady-state process. Subsequently, detailed CFD modeling approaches are employed to optimize complex adsorption and membrane enhanced reactive processes. Chapter one introduces an analytical model capable of calculating the reactor effluent concentrations for steady-state, non-isothermal Segregated Laminar Flow Reactors (SLFRs) regardless of the reactor geometry. The only requirement is knowledge of the SLFRs residence time density function. The existing analytical model for isothermal SLFRs is extended to also be applicable non-isothermal SLFRs for incompressible fluids. The accuracy of both the existing isothermal and the developed non-isothermal SLFR models are demonstrated in four case studies with two different reactor geometries by comparing the analytical results with results obtained from equivalent CFD simulations. The analytical results are shown to be within 2 % of the CFD generated values, rendering a CFD approach superfluous for SLFRs. Chapter two introduces a novel model of a Partial Pressure Temperature Swing Adsorptive Reactor (PPTSAR) process with application to the water gas shift reaction. In this Sorption Enhanced Water Gas Shift (SEWGS) process, a set of two PPTSARs, filled with both catalyst and adsorbent, are used. Alternating between two PPTSARs, a continuous syngas feed is converted to a stream of hydrogen and steam, free of carbon dioxide, in one reactor, while concurrently, steam is fed to the other PPTSAR to regenerate the adsorbent and capture the released carbon dioxide. This is realized by coupling a temperature and partial pressure swing between the reaction/adsorption and regeneration steps. These intensified PPTSARs can replace conventional water gas shift packed bed reactors in Integrated Gasification Combined Cycle (IGCC) power plants. The PPTASRs achieve carbon monoxide conversions greater than 98 % with simultaneous carbon dioxide capture. Chapter three presents the detailed derivation of the multidomain PPTSAR model including all employed assumptions used in Chapter two. Chapter four presents a significant performance improvement on the PPTSAR process in Chapter two, by demonstrating the effect of performing the regeneration step counter-currently to the reaction/adsorption step, as opposed to co-currently. As a result, an analogous process using Partial Pressure Swing Adsorptive Reactors (PPSARs) without the need for an additional temperature swing is presented. Finally, Chapters five and six present transient and steady-state multiscale membrane reactor models, respectively.

Process Intensification (PI) was borne out of a desire to meet ever stringent demands placed on the chemical process industry. These demands, expressed in terms of process objectives, include but are not limited to, reductions in waste generation, carbon emissions, utility consumption and capital and operating costs. PI also encompasses increases in energy efficiency and transition to green and sustainable chemical production. Meeting these objectives requires the application of unique techniques to identify and incorporate possible PI improvements in process design.

This dissertation features the application of several PI tools to various processes in the chemical process industry. In Chapter 1, the Energetic Self Sufficiency (ESS) tool is applied to the coproduction of Acetic acid and Hydrogen with no CO2 emissions. This PI tool is employed to other coproduction targets: Formic acid and Hydrogen (Chapter 2) and Dimethyl Ether and Hydrogen (Chapter 3). Next, the Atom Species Attainable Region (ASAR) concept is formally defined and applied to an equilibrium mixture of carbon monoxide, CO, carbon dioxide, CO2, hydrogen, H2, methanol, CH3OH, dimethyl ether, DME and water, H2O. In this chapter (Chapter 4), the atom-mol fraction space is explored for regions that maximize DME production while minimizing CH3OH formation. In Chapter 5, an updated technoeconomic analysis (TEA) of a commercial scale Integrated Gasification Combined Cycle (IGCC) power plant featuring intensified equipment, in the form of Membrane Reactors (MRs) and Adsorptive Reactors (ARs), is presented showing the benefits of the technology. In Chapter 6, the Infinite Dimensional State Space (IDEAS) conceptual framework is applied to an isobaric reactive distillation network featuring Vapor-Liquid Equilibrium (VLE), Vapor-Liquid-Liquid Equilibrium (VLLE), and Liquid-Liquid Equilibrium (LLE) flashes for the synthesis of Isopropyl Acetate.

This dissertation presents novel realizations in balancing the economical and environmental constraints in an energy intense world using: process network synthesis, energetic process enhancement concepts, carbon dioxide utilization and the deployment of renewable energy resources. Such balance is achieved through effective control and planning over resources and conditions. The mathematical optimization framework developed in this body of work can be found in chapters 1 and 2 while their applications are developed in chapters 3 and 4.

Chapter 1, introduce for the first time the Infinite Dimensional State-Space (IDEAS) based synthesis of reactor networks featuring multiple residence time distribution (MRTD) models in chapter 1. IDEAS is shown to be applicable to the MRTD synthesis problem containing a combination of Plug Flow reactor (PFR), Continuous Stirred-Tank Reactor (CSTR) and Segregated Laminar Flow Reactor (SLFR). The formulation which synthesis reactor networks featuring multiple residence time distribution (MRTD) guarantees global optimality through IDEAS based properties. Case studies featuring the Trambouze reaction scheme are carried out using the different reactor combinations and multiple selectivity and economical constraints.

Chapter 2, presents for the first time a design and synthesize framework for the minimum number of units reactor networks with multiple Residence time density functions of diffrent reactor types using the Infinite Dimensional State-Space (IDEAS) method. The works combines the usage of Plug Flow Reactor (PFR) and Continuous Stirred-Tank Reactor (CSTR) in constructing the reactor networks using an IDEAS based Mixed Integer Linear Programing (MILP) formulation. Case studies featuring the Trambouze reaction scheme are carried out based on multiple process specification. This work expands the real life application potential of the work presented in chapter 1.

In chapter 3, the newly developed concept of process energetics is applied to Steam Methane Reforming (SMR) to overcome the highly endothermic load challenge. The resulting process termed Energetically Enhanced Steam Methane Reforming (EESMR) is a non combustion process which means that the process related GHG emissions will receive favorable treatment in national carbon pricing programs.

Chapter 4 presents an energetically self-sufficient process with zero carbon dioxide emissions for the production of electricity and chemicals from natural gas. The choice of product can be made based on environmental and economical constraints explained within the chapter. Natural Gas Chemical Power System (NGCPS) provides flexibility of choice when it comes to producing electricity, formic acid and hydrogen. The work further covers the environmental impact of thermochemical cycles in power production.