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Full-Text Articles in Engineering

Constrained Control And Optimization Of Tubular Solid Oxide Fuel Cells For Extending Cell Lifetime, Ben Spivey, John Hedengren, Thomas F. Edgar Jul 2012

Constrained Control And Optimization Of Tubular Solid Oxide Fuel Cells For Extending Cell Lifetime, Ben Spivey, John Hedengren, Thomas F. Edgar

Faculty Publications

Extending fuel cell lifetime is a necessary objective for reducing fuel cell power generation cost of electricity. Capital costs comprise the most significant fraction of the cost of electricity. Reducing the frequency of fuel cell replacement can be achieved by implementing a control strategy that prevents excursions into operating regions causing failure. In this paper we implement a constrained MIMO model predictive controller (MPC) to avoid the failure modes relevant for a high-temperature tubular solid oxide fuel cell (SOFC) system while performing load-following. The primary causes of failure are catalyst poisoning, fuel or air starvation, carbon deposition, and microcracking. Prior …


Optimizing Fermentation Medium To Produce Cyclosporin A Using Response Surface Methodology, Rofiq Sunaryanto Apr 2012

Optimizing Fermentation Medium To Produce Cyclosporin A Using Response Surface Methodology, Rofiq Sunaryanto

Makara Journal of Technology

Response surface methodology (RSM) is a three factorial model which illustrates the relationship between one or more independent variables. RSM can be used to optimize the fermentation medium for the production of Cyclosporin A from the isolate Tolypocladium inflatum. The optimal point of the response surface area is predicted by using a seconddegree polynomial model and applying the statistic model obtained from the central composite design (CCD). The results of optimizing the fermentation medium for Cyclopsorin using the three independent variables of glucose, casein, and KH2PO4 show that all three of the independent variables affect the production of Cyclosporin A. …


Reactive Extraction Of Solid Coconut Waste To Produce Biodiesel, Abdul Aziz Abdul Raman Jan 2012

Reactive Extraction Of Solid Coconut Waste To Produce Biodiesel, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

Biodiesel is an alternative diesel fuel produced using transesterification method where edible or non edible oil and alcohol reacts in the presence of catalyst. Biodiesel is expensive than fossil fuels because of higher raw material and production costs. Solid coconut waste is an alternative raw material from waste and suitable for biodiesel production to lower the production cost. Solid coconut waste is produced after coconut milk extraction and may still contain 17–24 wt% extractable oil content. This study introduces reactive extraction of solid coconut waste for biodiesel production. Effects of catalyst amount, KOH (0.8–2.0%), temperature (55–65 °C) and mixing intensity …


Elucidation Of The Effect Of Ionic Liquid Pretreatment On Rice Husk Via Structural Analyses, Teck Nam Ang Dr., Gek Cheng Ngoh Dr, Adeline Seak May Chua Dr, Min Gyu Lee Prof Jan 2012

Elucidation Of The Effect Of Ionic Liquid Pretreatment On Rice Husk Via Structural Analyses, Teck Nam Ang Dr., Gek Cheng Ngoh Dr, Adeline Seak May Chua Dr, Min Gyu Lee Prof

Teck Nam Ang Dr.

Background: In the present study, three ionic liquids, namely 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc), and 1-ethyl-3-methylimidazolium diethyl phosphate ([EMIM]DEP), were used to partially dissolve rice husk, after which the cellulose were regenerated by the addition of water. The aim of the investigation is to examine the implications of the ionic liquid pretreatments on rice husk composition and structure. Results: From the attenuated total reflectance Fourier transform-infrared (ATR FT-IR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) results, the regenerated cellulose were more amorphous, less crystalline, and possessed higher structural disruption compared with untreated rice husk. The major component …


A Thermodynamic Framework For The Modeling And Optimization Of Crystallization Processes, David John Widenski Jan 2012

A Thermodynamic Framework For The Modeling And Optimization Of Crystallization Processes, David John Widenski

LSU Doctoral Dissertations

Crystallization is a widely used chemical engineering separation unit operation process. Since this technique can produce high purity products it is used for the industrial production of many chemical compounds, such as pharmaceuticals, agrochemicals, and fine chemicals. The production of these products is a multi-million dollar industry. Any methods to improve the production of these products would be highly valued. Thus, the main objective of this work is to target model-based optimal strategies for crystallization operations specifically targeting crystal size and crystal size distribution (CSD). In particular, take the knowledge gained and translate it into an economically and practically feasible …