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371	Control of transmission system power flows Kreikebaum, Frank Karl 13 January 2014 (has links) Power flow (PF) control can increase the utilization of the transmission system and connect lower cost generation with load. While PF controllers have demonstrated the ability to realize dynamic PF control for more than 25 years, PF control has been sparsely implemented. This research re-examines PF control in light of the recent development of fractionally-rated PF controllers and the incremental power flow (IPF) control concept. IPF control is the transfer of an incremental quantity of power from a specified source bus to specified destination bus along a specified path without influencing power flows on circuits outside of the path. The objectives of the research are to develop power system operation and planning methods compatible with IPF control, test the technical viability of IPF control, develop transmission planning frameworks leveraging PF and IPF control, develop power system operation and planning tools compatible with PF control, and quantify the impacts of PF and IPF control on multi-decade transmission planning. The results suggest that planning and operation of the power system are feasible with PF controllers and may lead to cost savings. The proposed planning frameworks may incent transmission investment and be compatible with the existing transmission planning process. If the results of the planning tool demonstration scale to the national level, the annual savings in electricity expenditures would be $13 billion per year (2010$). The proposed incremental packetized energy concept may facilitate a reduction in the environmental impact of energy consumption and lead to additional cost savings. Power flow control Transmission planning Power flow controller Controllable network transformer Distributed series reactance Fractionally-rated back-to-back Genetic algorithm Incremental power flow Merchant electrical pipeline Power purchase option Phase-shifting transformer Renewable portfolio standard Security-constrained optimal power flow Static synchronous series compensator Thyristor controlled series capacitor Optimal power flow CNT DSR CSCOPF FR-BTB GA IPF MEP PPO PSCOPF PST RPS SCOPF SSSC TCSC OPF Electric power distribution
372	Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications / Development of High-throughput Membrane Filtration Techniques Kazemi, Amir Sadegh 11 1900 (has links) Membrane filtration processes are widely utilized across different industrial sectors for biological and environmental separations. Examples of the former are sterile filtration and protein fractionation via microfiltration (MF) and ultrafiltration (UF) while drinking water treatment, tertiary treatment of wastewater, water reuse and desalination via MF, UF, nanofiltration (NF) and reverse-osmosis (RO) are examples of the latter. A common misconception is that the performance of membrane separation is solely dependent on the membrane pore size, whereas a multitude of parameters including solution conditions, solute concentration, presence of specific ions, hydrodynamic conditions, membrane structure and surface properties can significantly influence the separation performance and the membrane’s fouling propensity. The conventional approach for studying filtration performance is to use a single lab- or pilot-scale module and perform numerous experiments in a sequential manner which is both time-consuming and requires large amounts of material. Alternatively, high-throughput (HT) techniques, defined as the miniaturized version of conventional unit operations which allow for multiple experiments to be run in parallel and require a small amount of sample, can be employed. There is a growing interest in the use of HT techniques to speed up the testing and optimization of membrane-based separations. In this work, different HT screening approaches are developed and utilized for the evaluation and optimization of filtration performance using flat-sheet and hollow-fiber (HF) membranes used in biological and environmental separations. The effects of various process factors were evaluated on the separation of different biomolecules by combining a HT filtration method using flat-sheet UF membranes and design-of-experiments methods. Additionally, a novel HT platform was introduced for multi-modal (constant transmembrane pressure vs. constant flux) testing of flat-sheet membranes used in bio-separations. Furthermore, the first-ever HT modules for parallel testing of HF membranes were developed for rapid fouling tests as well as extended filtration evaluation experiments. The usefulness of the modules was demonstrated by evaluating the filtration performance of different foulants under various operating conditions as well as running surface modification experiments. The techniques described herein can be employed for rapid determination of the optimal combination of conditions that result in the best filtration performance for different membrane separation applications and thus eliminate the need to perform numerous conventional lab-scale tests. Overall, more than 250 filtration tests and 350 hydraulic permeability measurements were performed and analyzed using the HT platforms developed in this thesis. / Thesis / Doctor of Philosophy (PhD) / Membrane filtration is widely used as a key separation process in different industries. For example, microfiltration (MF) and ultrafiltration (UF) are used for sterilization and purification of bio-products. Furthermore, MF, UF and reverse-osmosis (RO) are used for drinking water and wastewater treatment. A common misconception is that membrane filtration is a process solely based on the pore size of the membrane whereas numerous factors can significantly affect the performance. Conventionally, a large number of lab- or full-scale experiments are performed to find the optimum operating conditions for each filtration process. High-throughput (HT) techniques are powerful methods to accelerate the pace of process optimization—they allow for multiple experiments to be run in parallel and require smaller amounts of sample. This thesis focuses on the development of different HT techniques that require a minimal amount of sample for parallel testing and optimization of membrane filtration processes with applications in environmental and biological separations. The introduced techniques can reduce the amount of sample used in each test between 10-50 times and accelerate process development and optimization by running parallel tests. Membrane filtration Ultrafiltration Downstream bio-processing High-throughput (HT) testing Wastewater treatment Hollow-fiber membranes Humic acids High-throughput filtration Design-of-experiments (DOE) Process optimization Microscale filtration Microfluidic flow control system Stirred well filtration SWF High-throughput hollow-fiber module HT-HF Constant TMP Constant flux Multi-modal filtration Bioseparation MMFC MS-PS-CFF PEG Dextran FITC-Dextran BSA DNA IgG α-lactalbumin Biomolecule separation Module hydrodynamics Concentration polarization Membrane fouling Micromixing Omega™ membrane Microscale processing Fouling test PVDF membrane Surface modification Polydopamine Membrane cleaning Membrane backwashing Sodium alginate Polyethersulfone PES Hydraulic permeability Membrane permeability ZeeWeed® membrane Filtration ionic strength Filtration pH Solution conditions Water treatment Environmental separations Biological separations

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Control of transmission system power flows

Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications / Development of High-throughput Membrane Filtration Techniques