Inferential estimation and control of chemical processes using partial least squares based model

The use of inferential estimation model as a strategy to overcome the lack of efficient on-line measurement for product qualities is proposed. This strategy makes use of easy to measure secondary variables, such as temperature and pressure to infer the value of non-measurable primary variables such...

Full description

Bibliographic Details
Main Author: Lim, Wan Piang
Format: Thesis
Language:English
Published: 2005
Subjects:
Online Access:http://eprints.utm.my/4216/
http://eprints.utm.my/4216/1/LimWanPiangMFKK2005.pdf
_version_ 1848890747960426496
author Lim, Wan Piang
author_facet Lim, Wan Piang
author_sort Lim, Wan Piang
building UTeM Institutional Repository
collection Online Access
description The use of inferential estimation model as a strategy to overcome the lack of efficient on-line measurement for product qualities is proposed. This strategy makes use of easy to measure secondary variables, such as temperature and pressure to infer the value of non-measurable primary variables such as chemical composition. As a case study, a fatty acid fractionation column from a local company was considered. The plant that was simulated using HYSYSTM simulator provided all the required process data throughout the study. To provide the necessary process insights, analyses of dynamic behaviour were carried out. Appropriate secondary measurements with significant relationships with the product composition were then identified for the construction of the inferential estimator within MATLAB® environment. A number of models were considered but nested neural network partial least squares (NNPLS) model was found most proficient. The model was tested online and reasonable performances were obtained. Further refinements were proposed to improve the accuracy and robustness of the estimator. In particular, the issue of data scaling was elaborately addressed. Following the success implementation of the estimator, inferential control of the product quality was examined. In both regulatory and servo controls, better performances were obtained compared to the indirect strategy of controlling product composition using selected tray temperature. This was further improved by employing cascade control. The results obtained throughout this work have illustrated the potential of inferential control strategy and the capability of the hybrid neural network-PLS model as the process estimator. This should therefore serve as an alternative solution to the lack of measurement in chemical process industry. The model developed from the simulation stage is specified to a particular case and it should be verified against the actual process before practical implementation.
first_indexed 2025-11-15T20:47:00Z
format Thesis
id utm-4216
institution Universiti Teknologi Malaysia
institution_category Local University
language English
last_indexed 2025-11-15T20:47:00Z
publishDate 2005
recordtype eprints
repository_type Digital Repository
spelling utm-42162018-01-16T04:32:48Z http://eprints.utm.my/4216/ Inferential estimation and control of chemical processes using partial least squares based model Lim, Wan Piang TP Chemical technology The use of inferential estimation model as a strategy to overcome the lack of efficient on-line measurement for product qualities is proposed. This strategy makes use of easy to measure secondary variables, such as temperature and pressure to infer the value of non-measurable primary variables such as chemical composition. As a case study, a fatty acid fractionation column from a local company was considered. The plant that was simulated using HYSYSTM simulator provided all the required process data throughout the study. To provide the necessary process insights, analyses of dynamic behaviour were carried out. Appropriate secondary measurements with significant relationships with the product composition were then identified for the construction of the inferential estimator within MATLAB® environment. A number of models were considered but nested neural network partial least squares (NNPLS) model was found most proficient. The model was tested online and reasonable performances were obtained. Further refinements were proposed to improve the accuracy and robustness of the estimator. In particular, the issue of data scaling was elaborately addressed. Following the success implementation of the estimator, inferential control of the product quality was examined. In both regulatory and servo controls, better performances were obtained compared to the indirect strategy of controlling product composition using selected tray temperature. This was further improved by employing cascade control. The results obtained throughout this work have illustrated the potential of inferential control strategy and the capability of the hybrid neural network-PLS model as the process estimator. This should therefore serve as an alternative solution to the lack of measurement in chemical process industry. The model developed from the simulation stage is specified to a particular case and it should be verified against the actual process before practical implementation. 2005-06 Thesis NonPeerReviewed application/pdf en http://eprints.utm.my/4216/1/LimWanPiangMFKK2005.pdf Lim, Wan Piang (2005) Inferential estimation and control of chemical processes using partial least squares based model. Masters thesis, Universiti Teknologi Malaysia, Faculty of Chemical and Natural Resources Engineering.
spellingShingle TP Chemical technology
Lim, Wan Piang
Inferential estimation and control of chemical processes using partial least squares based model
title Inferential estimation and control of chemical processes using partial least squares based model
title_full Inferential estimation and control of chemical processes using partial least squares based model
title_fullStr Inferential estimation and control of chemical processes using partial least squares based model
title_full_unstemmed Inferential estimation and control of chemical processes using partial least squares based model
title_short Inferential estimation and control of chemical processes using partial least squares based model
title_sort inferential estimation and control of chemical processes using partial least squares based model
topic TP Chemical technology
url http://eprints.utm.my/4216/
http://eprints.utm.my/4216/1/LimWanPiangMFKK2005.pdf