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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Dynamic modeling, optimization, and control of monoethanolamine scrubbing for CO2 capture

Ziaii Fashami, Sepideh 13 November 2012 (has links)
This work seeks to develop optimal dynamic and control strategies to operate post combustion CO2 capture in response to various dynamic operational scenarios. For this purpose, a rigorous dynamic model of absorption/stripping process using monothanolamine was created and then combined with a simplified steady state model of power cycle steam turbines and a multi-stage variable speed compressor in Aspen Custom Modeler. The dynamic characteristics and interactions were investigated for the plant using 30% wt monoethanolamine (MEA) to remove 90% of CO2 in the flue gas coming from a 100 MW coal-fired power plant. Two load reduction scenarios were simulated: power plant load reduction and reboiler load reduction. An ACM® optimization tool was implemented to minimize total lost work at the final steady state condition by adjusting compressor speed and solvent circulation rate. Stripper pressure was allowed to vary. Compressor surge limit, run off condition in rich and lean pumps, and maximum allowable compressor speed were found as constraints influencing the operation at reduced loads. A variable speed compressor is advantageous during partial load operations because of its flexibility for handling compressor surge and allowing the stripper and reboiler to run at optimal conditions. Optimization at low load levels demonstrated that the most energy efficient strategy to control compressor surge is gas recycling which is commonly applied by an anti-surge control system installed on compressors. Trade offs were found between initial capital cost and optimal operation with minimal energy use for large load reduction. The examples are, designing the stripper in a way that can tolerate the pressure two times larger than normal operating pressure, over sizing the pumps and over designing the compressor speed. A plant-wide control procedure was used to design an effective multi-loop control system. Five control configurations were simulated and compared in response to large load variations and foaming in the stripper and the absorber. The most successful control structure was controlling solvent rate, reboiler temperature, and stripper pressure by liquid valve, steam valve, and compressor speed respectively. With the investigated disturbances and employing this control scheme, development of an advanced multivariable control system is not required. This scheme is able to bring the plant to the targeted set points in about 6 minutes for such a system designed initially with 11 min total liquid holdup time.Frequency analysis used for evaluation of lean and rich tanks on the dynamic performances has shown that increasing the holdup time is not always helpful to damp the oscillations and rejecting the disturbances. It means there exists an optimum initial residence time in the tanks. Based on the results, a 5-minute holdup can be a reasonable number to fulfill the targets. / text
162

Innovative techniques for industrial process modeling and monitoring

He, Qinghua 28 August 2008 (has links)
Not available / text
163

Closed-loop subspace identification and fault diagnosis with optimal structured residuals

Lin, Weilu 28 August 2008 (has links)
Not available / text
164

Process instrumentation for laboratory instruction

Brinker, Fred Eugene, 1949- January 1973 (has links)
No description available.
165

Design and evaluation of a process plant simulator

Fath, Janet Louise 12 1900 (has links)
No description available.
166

Techniques in data acquisition and control

Le-Ngoc, Tho. January 1978 (has links)
No description available.
167

Analysis of users' procedural compliance in controlling a simulated process

Mann, Olga Teresa Lopez 12 1900 (has links)
No description available.
168

Effects of withholding information about implementation details on the design of a human-computer interface

Russell, C. Ray 05 1900 (has links)
No description available.
169

Nonlinear model predictive control of a semi-batch emulsion polymerization reactor

Agarwal, Naveen January 1993 (has links)
No description available.
170

Adaptive optimizing control of a semibatch polymerization reactor

Houston, William Edward 05 1900 (has links)
No description available.

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