Science and Education Publishing Chemical Engineering and Science 2328-7373 1 1 2013 07 15 Calculation of Radiant Section Temperatures in Fired Process Heaters 55 61 EN Hassan Al-Haj Ibrahim Department of Chemical Engineering, Al-Baath University, Homs, Syria M. Mourhaf Al-Qassimi CES2013142 10.12691/ces-1-4-2 2013 05 15 2013 06 15 2013 07 15 Flame and effective gas temperatures are key variables that need to be accurately determined before analysis of heat transfer in the radiant section of fired heaters can be meaningfully undertaken. To facilitate the calculation of these temperatures, appropriate equations were derived using two Computer Matlab programmes specially written for the purpose. A third programme was also written for the solution of the derived equations using the Newton-Raphson method. The whole calculation procedure was illustrated by an example worked out for an actual process heater used in a crude oil topping unit.