Integration of Product Quality Estimation and Operating Condition Monitoring for Efficient Operation of Industrial Ethylene Fractionator

Abstract In this industry-university collaboration, a soft sensor for measuring a key product quality and a monitoring system for testing the validity of the soft sensor were developed to realize highly efficient operation of the ethylene production plant. To estimate impurity concentrations in ethylene products from online measured process variables, dynamic partial least squares (PLS) models were developed. The developed soft sensor can estimate the product quality very well, but it does not function well when the process is operated under unexperienced conditions. Therefore, a monitoring system was developed to judge whether the soft sensor is reliable based on the dynamic PLS model. In addition, simple rules were established for checking the performance of a process gas chromatograph by combining the soft sensor and the monitoring system. The soft sensor and the monitoring system have functioned successfully.

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