(316f) Application of Multistate Analytics to CO2 Capture Processes

Multi-way PCA [1][2] and multi-block multi-way PLS [3][4] have significantly enhanced process monitoring of batch processes by providing expected trajectory profiles for process variables along the duration of a batch. However, continuous processes lack of an equivalent technology because of their flexible operations and undefined time duration. This work presents a novel methodology to define operating regions where continuous processes operate. Such operating regions are determined by special variables, named state variables. Transition trajectories between regions or states of operation are calculated to determine the most likely profile in terms of state variable changes. This methodology can be implemented in the context of empirical monitoring methods, named Multistate PCA.

This work applies Multistate PCA to a CO₂ recovery pilot plant [5]. The CO₂ capture process with amine solvent based absorption and stripping is the most significant industrial method for the removal of carbon dioxide from coal and natural gas-fired power plants. The use of CO₂ capture process data shows how Multistate PCA could enhance fault diagnostics and statistical monitoring for continuous processes.

References

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[2] S. Qin, Statistical process monitoring: basics and beyond, JOURNAL OF CHEMOMETRICS 17 (8-9) (2003) 480–502, 3rd International Chemomtrics Research Meeting (ICRM2002), VELDHOVEN, NETHERLANDS, MAY 26-30, 2002.

[3] J. Flores-Cerrillo, J. MacGregor, Multivariate monitoring of batch processes using batch-to-batch information, AICHE JOURNAL 50 (6) (2004) 1219–1228.

[4] J. C. Gunther, J. S. Conner, D. E. Seborg, Process monitoring and quality variable prediction utilizing PLS in industrial fed-batch cell culture, JOURNAL OF PROCESS CONTROL 19 (5) (2009) 914–921.

[5] G. T. Rochelle, Amine Scrubbing for CO₂ Capture, SCIENCE, 325 (5948) (2009) 1652 -1654