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Distillation columns are primary equipment in petrochemical, gas plants and refineries. Distillation columns energy consumption is estimated to be 40% of the total plant energy consumption. Optimization of distillation columns has potential for saving large amount of energy and contributes to plant wide optimization. Currently rigorous tray to tray models are used to describe columns separation with high accuracy. Rigorous distillation models are being used as part of design, optimization and as a part of on-line real-time optimization applications. Due to large number of nonlinear equations, rigorous distillation models are not suitable for inclusion in optimization models of complex plants (e.g. refineries), since they would make the model too large. For this reason, current practice in plant-wide optimization for planning or for scheduling is to include simplified model. Accuracy of these simplified models is significantly lower than the accuracy of the rigorous models, thereby causing discrepancy between production planning and RTO decisions. This work describes reduced size hybrid model of distillation columns, suitable for use as stand-alone tool for individual column or as part of a complete plant model, either for RTO or for production planning. Hybrid models are comprised of first principles material and energy balances and empirical models describing separation in the column. Hybrid models can be used for production planning, scheduling and optimization. In addition this work describes inferential model development for estimating streams purity using real time data. Inferential model eliminates the need for Gas Chromatography GC analyzers and can be used for monitoring and control purposes. Predictions from the models are sufficiently accurate and small size of the models enable significant reduction in size of the total plant models. / Thesis / Master of Applied Science (MASc)

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The trematode Bolbophorus damnificus (Digenea: Bolbophoridae) has deleterious effects on production efficiency of farm-raised catfish. The effects of B. damnificus on channel and hybrid catfish, as well as the prevalence and longevity of the trematode stages impacting production, are not well understood. This study aimed to understand the prevalence of infected snails, determine the longevity and site specificity of B. damnificus cercaria in catfish, and compare mortality and physiological response between channel and hybrid catfish during infection. The infectivity and survival of B. damnificus cercariae declined significantly at 12h intervals from 12-36h, and subsequent trials were standardized using cercariae <12h old. Metacercariae persisted in both fish types for 13 months and were found commonly in the posterior midsection. Hybrid catfish exhibited lower mortality than channel catfish. Exposed catfish exhibited anemia corresponding to parasite encapsulation, however no difference was found between fish types in physiological response during infection and subsequent recovery.

This document describes the design of an axisymmetric aerospike nozzle to replace the conical converging-diverging nozzle of a commercially available hybrid rocket motor. The planar method of characteristics is used with isentropic flow assumptions to design the nozzle wall. Axisymmetric adjustments are made with quasi-one-dimensional flow approximations. Computational Fluid Dynamics (CFD) simulations verify these assumptions, and illustrate viscous effects within the flow. Nozzle truncations are also investigated. Development of a hybrid-rocket-specific data acquisition system is also detailed.

Stringent government mandates for the fuel economy and emissions of light-duty consumer vehicles have forced manufacturers to focus on improvements in these areas. Increased consumer pressure has also shifted the automobile market towards higher efficiency vehicles. This study investigates the use of intelligent engine peripheral control to improve fuel efficiency and reduce vehicle emissions. The conventional automotive alternator control strategy contributes to higher overall vehicle losses and increased fuel consumption through indiscriminate loading of the engine. The improved method focuses on the selective reduction of engine loading and the recapture of vehicle energy during braking using intelligent control of the alternator system. The concept was demonstrated on the Mississippi State University Challenge X hybrid vehicle. The fuel economy and NOx emissions of the vehicle were improved by 6.6% and 10.5% respectively over the drive cycle developed by the 2006 Mississippi State University Challenge X team to evaluate emissions.

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