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(1 - 7 of 7)
Statistical monitoring of multistage, multiphase batch processes
Title
Statistical monitoring of multistage, multiphase batch processes
Creator
Undey, C., Cinar, A.
Date
2002-10
Publisher
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Description
The monitoring of intermediate phases of production is as important as monitoring and control of the final stage. Here a framework is proposed...
Show moreThe monitoring of intermediate phases of production is as important as monitoring and control of the final stage. Here a framework is proposed for monitoring overall process performance at the end of each batch.
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A modular simulation package for fed-batch fermentation: penicillin production
Title
A modular simulation package for fed-batch fermentation: penicillin production
Creator
Birol, G., Undey, C., Cinar, A.
Date
2002-11-15
Publisher
PERGAMON-ELSEVIER SCIENCE LTD
Description
Simulation software based on a detailed unstructured model for penicillin production in a fed-batch fermentor has been developed. The model...
Show moreSimulation software based on a detailed unstructured model for penicillin production in a fed-batch fermentor has been developed. The model extends the mechanistic model of Bajpai and Reuss by adding input variables such as pH, temperature, aeration rate, agitation power, and feed flow rate of substrate and introducing the CO2 evolution term. The simulation package was then used for monitoring and fault diagnosis of a typical penicillin fermentation process. The simulator developed may be used for both research and educational purposes and is available at the web site: http://www.chee.iit.edu/ similar to control/software.html.
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Online batch/fed-batch process performance monitoring, quality prediction, and variable-contribution analysis for diagnosis
Title
Online batch/fed-batch process performance monitoring, quality prediction, and variable-contribution analysis for diagnosis
Creator
Undey, C., Ertunc, S., Cinar, A.
Date
2003-10-01
Publisher
AMER CHEMICAL SOC
Description
An integrated online multivariate statistical process monitoring (MSPM), quality prediction, and fault diagnosis framework is developed for...
Show moreAn integrated online multivariate statistical process monitoring (MSPM), quality prediction, and fault diagnosis framework is developed for batch processes. Batch data from I batches, with J process variables measured at K time points generate a three-way array of size I x K x J. Unfolding this three-way array into a two-way matrix of size IK x J by preserving the variable direction is advantageous for developing online MSPM methods because it does not require estimation of future portions of new batches. Two different multiway partial least squares (MPLS) models are developed. The first model (MPLSV) is developed between the data matrix (IK x J) and the local batch time (or an indicator variable) for online MSPM. The second model (MPLSB) is developed between the rearranged data matrix in the batch direction (I x KJ) and the final quality matrix for online prediction of end-of-batch quality. The problem of discontinuity in process variable measurements due to operation switching (or moving to a different phase) that causes problems in alignment and modeling is addressed. Control limits on variable contribution plots are used to improve fault diagnosis capabilities of the MSPM framework. Case studies from a simulated fed-batch penicillin fermentation illustrate the implementation of the methodology.
Endnote format citation for DOI:10.1021/ie0208218
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Intelligent real-time performance monitoring and quality prediction for batch/fed-batch cultivations
Title
Intelligent real-time performance monitoring and quality prediction for batch/fed-batch cultivations
Creator
Undey, C., Tatara, E., Cinar, A.
Date
2004-02-19
Publisher
ELSEVIER SCIENCE BV
Description
Supervision of batch bioprocess operations in real-time during the progress of a batch run offers many advantages over end-of-batch quality...
Show moreSupervision of batch bioprocess operations in real-time during the progress of a batch run offers many advantages over end-of-batch quality control. Multivariate statistical techniques such as multiway partial least squares (MPLS) provide an efficient modeling and supervision framework. A new type of MPLS modeling technique that is especially suitable for online real-time process monitoring and the multivariate monitoring charts are presented. This online process monitoring technique is also extended to include predictions of end-of-batch quality measurements during the progress of a batch run. Process monitoring, quality estimation and fault diagnosis activities are automated and supervised by embedding them into a real-time knowledge-based system (RTKBS). Interpretation of multivariate charts is also automated through a generic rule-base for efficient alarm handling. The integrated RTKBS and the implementation of MPLS-based process monitoring and quality control are illustrated using a fed-batch penicillin production benchmark process simulator.
Endnote format citation for DOI:10.1016/j.jbiotec.2003.10.004
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Real-time batch process supervision by integrated knowledge-based systems and multivariate statistical methods
Title
Real-time batch process supervision by integrated knowledge-based systems and multivariate statistical methods
Creator
Undey, C., Tatara, E., Cinar, A.
Date
2003-08
Publisher
PERGAMON-ELSEVIER SCIENCE LTD
Description
Real-time supervision of batch operations during the progress of a batch run offers many advantages over end-of-batch quality control. Process...
Show moreReal-time supervision of batch operations during the progress of a batch run offers many advantages over end-of-batch quality control. Process monitoring, quality estimation, and fault diagnosis activities are automated and supervised by embedding them into a real-time knowledge-based system (RTKBS). Interpretation of multivariate charts is also automated through a generic rule-base for efficient alarm handling and fault diagnosis. Multivariate statistical techniques such as multiway partial least squares (MPLS) provide a powerful modeling, monitoring, and supervision framework. Online process monitoring techniques are developed and extended to include predictions of end-of-batch quality measurements during the progress of a batch run. The integrated RTKBS and the implementation of MPLS-based process monitoring and quality control are illustrated using a fed-batch penicillin production benchmark process simulator.
Endnote format citation for DOI:10.1016/j.engappai.2003.09.003
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A morphologically structured model for penicillin production
Title
A morphologically structured model for penicillin production
Creator
Birol, G., Undey, C., Parulekar, S. J., Cinar, A.
Date
2002-03-05
Publisher
JOHN WILEY & SONS INC
Description
A morphologically structured model is proposed to describe penicillin production in fed-batch cultivations. The model accounts for the effects...
Show moreA morphologically structured model is proposed to describe penicillin production in fed-batch cultivations. The model accounts for the effects of dissolved oxygen on cell growth and penicillin production and variations in volume fractions of abiotic and biotic phases due to biomass formation. Penicillin production is considered to occur in the subapical hyphal cell compartment and to be affected by availability of glucose and oxygen. As it stands, the model provides a wide range of applicability in terms of operating conditions. The model has been tested for various conditions and has given satisfactory results. A series of glucose feeding profiles have been considered to demonstrate the capabilities of the proposed model. It is concluded that the model may be valuable for the interpretation of experimental data collected specifically for metabolic flux analysis during fed-batch cultivation because the elements of measured specific production rates are determined from measurements of the concentrations of the components and their mass balances. The proposed model may be further used for developing control strategies and model order reduction algorithms
Endnote format citation for DOI:10.1002/bit.10115
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Batch process monitoring and its application to polymerization systems
Title
Batch process monitoring and its application to polymerization systems
Creator
Undey, C., Ertunc, S., Tatara, E., Teymour, F., Cinar, A.
Date
2004-01
Publisher
WILEY-V C H VERLAG GMBH
Description
Slight changes in raw material properties or operating conditions during critical periods of operation of batch and semi-batch polymerization...
Show moreSlight changes in raw material properties or operating conditions during critical periods of operation of batch and semi-batch polymerization reactors may have a strong influence on reaction mechanism and impact final product quality. Online process monitoring, fault detection, fault diagnosis, and product quality prediction in real-time ensure safe reactor operation and warn operators about excursions from normal operation that may lead to deterioration in product properties. Multivariate statistical process monitoring and quality prediction using multiway principal components analysis and multiway partial least squares have been successful in detecting abnormalities in process operation and product quality. When abnormal process operation is detected, fault diagnosis tools are used to determine the source cause of the deviation. Illustrative case studies are presented via simulated polyvinyl acetate polymerization.
Endnote format citation for DOI:10.1002/masy.200450210
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