Numerical Simulation of Gas/Oil Co-Combustion Process and Thermal NO_x Formation in a Retrofitted Oil-Burning Boiler

The purpose of this paper is to realize oil/gas co-combustion in an oil-burning boiler and to examine the effect of co-combustion of heavy fuel oil and refinery gas on the thermal NOx formation. The analysis was carried out by means of 3-D numerical simulation. Comprehensive mathematical model of the furnace was setup to include all relevant aerodynamic and thermo-chemical processes in the furnace. Heat transferred to the furnace walls and temperature field in the furnace were also examined in order to establish regions of safe and efficient boiler operation for different operational conditions. Realization of oil/gas co-firing safely, efficiently and with lower NOx emission in many old oil-burning boilers by retrofitting does not only deal with combustible waste gas, but also take advantage of thermal energy from the refinery gas.