(57e) Predictive and Real-Time Heat Flux Monitoring for Burners in Ethylene Furnaces

Heat flux in ethylene furnaces is a complex function of three main factor types: burner-related factors such as burner type and location; operating factors such as fuel composition and bridgewall temperature; and, furnace-related factors such as height and width. Theoretical heat-flux relations were developed for floor-fired and floor+wall fired configurations. The analysis identified several parameters, some of which could be determined a priori; those remaining were fit a posteriori using a large data set (five furnaces, five burner types, and nearly 1000 heat flux measurements) in order to construct a semi-empirical model. The mathematical model was then coded into a design tool and validated with additional data. Based on the theory, a real-time heat flux measurement profile tool was developed and is in use at John Zink Co.'s test facility. This paper discusses the general development effort.