Format:
Online-Ressource
ISSN:
1521-4125
Content:
Abstract: A hybrid neural network model based on‐line reoptimization control strategy is developed for a batch polymerization reactor. To address the difficulties in batch polymerization reactor modeling, the hybrid neural network model contains a simplified mechanistic model covering material balance assuming perfect temperature control, and recurrent neural networks modeling the residuals of the simplified mechanistic model due to imperfect temperature control. This hybrid neural network model is used to calculate the optimal control policy. A difficulty in the optimal control of batch polymerization reactors is that the optimization effort can be seriously hampered by unknown disturbances such as reactive impurities and reactor fouling. With the presence of an unknown amount of reactive impurities, the off‐line calculated optimal control profile will be no longer optimal. To address this issue, a strategy combining on‐line reactive impurity estimation and on‐line reoptimization is proposed in this paper. The amount of reactive impurities is estimated on‐line during the early stage of a batch by using a neural network based inverse model. Based on the estimated amount of reactive impurities, on‐line reoptimization is then applied to calculate the optimal reactor temperature profile for the remaining time period of the batch reactor operation. This approach is illustrated on the optimization control of a simulated batch methyl methacrylate polymerization process.
Content:
A hybrid neural network modeling scheme is presented and demonstrated to be superior to the basic mechanistic model. A novel strategy combining on‐line estimation of reactive impurities and reoptimization is proposed and applied to a simulated batch MMA polymerization reactor. The amount of reactive impurities is estimated on‐line during the early stage of a batch and on‐line reoptimization, based on the hybrid neural network model, is then carried out. Application results demonstrate that the proposed technique is very effective in overcoming the detrimental effects of reactive impurities on the desired final product quality.
In:
volume:27
In:
number:9
In:
year:2004
In:
pages:1030-1038
In:
extent:9
In:
Chemical engineering & technology, Weinheim : Wiley-VCH Verl.-Ges., 1987-, 27, Heft 9 (2004), 1030-1038 (gesamt 9), 1521-4125
Language:
English
DOI:
10.1002/ceat.200402068
URN:
urn:nbn:de:101:1-2023100207185748064764
URL:
https://doi.org/10.1002/ceat.200402068
URL:
https://nbn-resolving.org/urn:nbn:de:101:1-2023100207185748064764
URL:
https://d-nb.info/130469433X/34
URL:
https://doi.org/10.1002/ceat.200402068
