The ability to produce potable water economically is the primary purpose of seawater desalination research. Reverse osmosis (RO) and multi-stage flash (MSF) cost more than potable water produced from fresh water resources. As an alternative to RO and MSF, this research investigates a high-efficiency mechanical vapor-compression distillation system that employs an improved water flow arrangement. The incoming salt concentration was 0.15% salt for brackish water and 3.5% salt for seawater, whereas the outgoing salt concentration was 1.5% and 7%, respectively. Distillation was performed at 439 K (331oF) and 722 kPa (105 psia) for both brackish water feed and seawater feed. Water costs of the various conditions were calculated for brackish water and seawater feeds using optimum conditions considered as 25 and 20 stages, respectively. For brackish water at a temperature difference of 0.96 K (1.73oF), the energy requirement is 2.0 kWh/m3 (7.53 kWh/kgal). At this condition, the estimated water cost is $0.39/m3 ($1.48/kgal) achieved with 10,000,000 gal/day distillate, 30-year bond, 5% interest rate, and $0.05/kWh electricity. For seawater at a temperature difference of 0.44 K (0.80oF), the energy requirement is 3.97 kWh/m3 (15.0 kWh/kgal) and the estimated water cost is $0.61/m3 ($2.31/kgal). Greater efficiency of the vapor compression system is achieved by connecting multiple evaporators in series, rather than the traditional parallel arrangement. The efficiency results from the gradual increase of salinity in each stage of the series arrangement in comparison to parallel. Calculations using various temperature differences between boiling brine and condensing steam show the series arrangement has the greatest improvement at lower temperature differences. The following table shows the improvement of a series flow arrangement compared to parallel: ?T (K) Improvement (%)*1.111 2.222 3.333 15.21 10.80 8.37 * Incoming salt concentration: 3.5% Outgoing salt concentration: 7% Temperature: 450 K (350oF) Pressure: 928 kPa (120 psig) Stages: 4

Tunable diode laser spectroscopy and the Beer-Lambert relation has been used to measure the absorption of water vapor both in an absorption cell and in a shock tube. The purpose of this thesis is to develop a laser diagnostic capable of determining species concentration. The correlation between species concentration and absorption is known, and if one is known the other can be calculated. A diode laser was obtained which has a tunable range of 1325.7 - 1400.8 nm and is centered at 1384 nm. An experimental setup was created in which the laser was used to obtain absorption spectroscopy data for water vapor within two separate scenarios- in an absorption cell and in a shock tube. A model was constructed which enabled the calculation of the Voigt profile which in turn was used to determine the absorption coefficient and ultimately enable the utilization of absorption spectroscopy principles to determine species concentration and/or absorption percentage. The experiments for the absorption cell were performed at room temperature. Twenty runs were performed and the average error for all runs was less than one percent. Three runs were performed for the shock-tube experiments. The absorption was calculated at three times- prior to the arrival of the shock, after the incident shock passed, and after the reflected shock passed. The temperatures for these conditions were 296K, 1060K, and 2000K respectively. These experiments showed reasonable agreement with theoretical calculations.

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Abstract The development and advancement of microelectronics technology has been very dramatic. However the cost of creating new process technology by using experiment has been very high. By using computer simulation to evaluate the performance of these equipment, we are able to achieve the same goal at a much lower cost. The reactor of chemical vapor deposition (CVD) is very important to semiconductor production process. This research use numerical method (simulation) to study the process parameters of Low-Pressure Chemical Vapor Deposition (LPCVD) of silicon (Si). In this simulation, the CVD reactor modelings are constructed and discredited by using implicit finite volume method. The grids are arranged in a staggered manner for the discretization of the governing equations. Then the SIMPLE-type algorithm is used to solve all of the discretized algebra equations. Many people in the field are beginning to realize that these challenges can no longer be tackled with the traditional trial-and-error method which have dominated the CVD technology since its beginning, and that modeling may lead to better process and equipment design, reduced costs, and improved IC manufacturing. It is also to be expected that in the future, detailed CVD simulation models will not only be used in design and optimization, but also in real-time process control. Key word: chemical vapor deposition, flow simulation, natural convection.

El presente trabajo muestra la forma de desarrollar la validación de uno de los pilares dentro del sistema de apoyo crítico en la industria farmacéutica: la Validación Prospectiva del Sistema Generador de Vapor Limpio, de tal manera que se establezca una evidencia documentada de que el proceso es capaz de cumplir en forma consistente y repetitiva las especificaciones establecidas. Se procedió a elaborar los protocolos en donde se definen los objetivos específicos de las evaluaciones a efectuar, las responsabilidades de cada una de las áreas involucradas; se establecieron variables de interés a monitorear, incluyendo el plan de monitoreo respectivo, además de incluir los criterios de aceptación que luego se compararon con los resultados esperados. Posteriormente se desarrollo el proceso de validación propiamente dicho, en el cuál se realizó una evaluación del proceso y se hicieron pruebas de que todos los componentes del sistema funcionan según lo especificado. Se sometió a prueba todos los controles de operación normal, verificación: del sistema generador, del sistema de control, de alarmas, de bomba, y de niveles de agua. Se hizo la calificación de desempeño, para la cuál se analizaron el perfil de pureza: control físico-químico (pH, conductividad, sustancias oxidables y sólidos totales) y control microbiológico (prueba de endotoxinas y carga microbiana) del condensado de vapor en el punto de uso por 30 días. Con los resultados obtenidos se concluye que el vapor producido por el generador de vapor limpio en una industria farmacéutica local es apto para su uso. Palabras Claves: Validación, Sistema, Generador, Vapor, Pureza. / The present work shows the form to develop the validation of one of the pillars within the system of critical support in the pharmaceutical industry: the Prospective Validation of the Generating Clean Steam System, in order to establish documentary evidence that the process is able to fulfill in consistent and repetitive form the established specifications. The protocols were elaborated in which the specific objectives of the evaluations, the responsibilities of each of the involved areas are defined to carry out; interest variables to monitor were established including the respective plan of monitoring; besides to sit includes the acceptance criterias which will be compared with the expected results afterwards. Then, the validation process itself was developed, in which an evaluation of the process was made and all the components of the system were tested to check whether they work according to the specifications or not. All the controls of normal operation were checked, verification: of the generating system, of the control system, alarms, pump, and water levels. The qualification of performance was made, for which analyzed the purity profile was analyzed: physical-chemistry control (pH, conductivity, rusty substances and total solid) and microbiological control (test of endotoxins and microbial load) of the condensed steam in the point of use by 30 days. With the obtained results we conclude that the steam produced by the clean steam generator in a local pharmaceutical industry is suitable for its use. Key Words: Validation, System, Generator, Steam, Purity.

Thesis (Ph. D.)--University of Michigan, 1929. / Cover title. "By Marvin C. Rogers and Geo. Granger Brown."

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references (leaves 163-173). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

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