Forecast of Polyethylene Properties in the Gas Phase Polymerization Aided by Neural Network
A major problem that affects the quality control of polymer in the industrial polymerization is the lack of suitable on-line measurement tools to evaluate the properties of the polymer such as melt and density indices. Controlling the polymerization in ordinary method is performed manually by taking samples, measuring the quality of polymer in the lab and registry of results. This method is highly time consuming and leads to producing large number of incompatible products. An online application for estimating melt index and density proposed in this study is a neural network based on the input-output data of the polyethylene production plant. Temperature, the level of reactors' bed, the intensity of ethylene mass flow, hydrogen and butene-1, the molar concentration of ethylene, hydrogen and butene-1 are used for the process to establish the neural model. The neural network is taught based on the actual operational data and back-propagation and Levenberg-Marquart techniques. The simulated results indicate that the neural network process model established with three layers (one hidden layer) for forecasting the density and the four layers for the melt index is able to successfully predict those quality properties.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.3455593Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 349
 Abedi, S. Vahdadi Asl, Fall 2007, publisher: Petrochemical Research & Technology Co. 1st Ed. Polyolefin.
 F. Rodriguez, "principles of polymer systems", Taylor & Francis, 1996, p2.
 Resin plastics (LDPE,HDPE,PP,PS,PVC,ABS,PMMA). Chem. Rep.2000, 120, 37.
 K.B. MCAuley, J.F. MacGregor, "on-line inference of polymer properties in an industrial polyethylene reactor”, ALCHE J. 37 (6) (1991) 825-835
 M. Ogawa, M. Ohshima, K. Morinaga and F. Watanabe; "Quality inferential control of an industrial High Density Polyethylene Process," J. Process Control, 9, 51-59 (1999)
 P. Thitiyasook, P. Kittisupakorn, S. Niamsuwan, K. Konakom; "on-line neural network estimator of polymerization plant".17th European Symposium on Computer Aided Process Engineering – ESCAPE17 (2007)
 M. Ohshima, M.Tanigaki, "Quality control of polymer production processes", J. of process control, 2000, pp.135-145
 M.Karthikeyan, J. Chem. Inf. Model. , 45, 581 (2005)
 A. Afantitis, G Melagraki, K. Makridima, A. Alexandridis , H.Sarimveis and O. Iglessi- Markopoulou, J. Molecular Structure, 716 , 193(2005)