Part II. Deployment of Continuous Online Monitoring of Local Tube Metal Temperature of a Refinery Depropanizer Reboiler

Paper from the AFRC 2016 conference titled Part II. Deployment of Continuous Online Monitoring of Local Tube Metal Temperature of a Refinery Depropanizer Reboiler

Continuous monitoring of local tube metal temperatures of process tubes is a difficult but desired objective for the safe and efficient operation of many process heaters and boilers.; A new measurement technology has been developed (see Part I. paper by the same authors presented at the 2015 AFRC meeting, Salt Lake City) for providing local tube metal; temperatures in such furnaces. With this paper we present the deployment and validation of this technology on the refinery process heater serving as a reboiler for the bottoms of a; depropanizer tower at the HollyFrontier Refinery in Woods Cross, Utah.; The technology brings together the existing process data acquisition on the process heater with high performance computer simulations of the combustion system coupled to; the thermodynamic properties of the multiphase process fluid, and with Bayesian learning from the historical data. By using these technologies together, an instrument model is; constructed to provide the local tube metal temperature throughout the radiant section of the reboiler. The continuous measurement of tube metal temperature is updated as the; existing measurements of operating variables (the process fluid temperature at the inlet and outlet of each coil in the heater, the process composition, process flow rates, and the; combustion stack gas temperature) are updated. The instrument model is calibrated and updated as new data are acquired.; This measurement technology has been tested offline on four months of historical data collected during the fall and winter of 2015. Subsequently, the method has been; hardened for deployment online, calibrated with optical data collected at the refinery, continuously validated with online process data, and deployed at the refinery. This paper; reports on the experience of testing, calibrating, validating, and deploying this technology.