Fired heaters design

In the vei tical-tube single-row double-fired heater, a single row of vertical tubes is arrayed along the center plane of the radiant section that is fired from both sides. Usually this type of heater has an overhead horizontal convec tion bank. Although it is the most expensive of the fired heater designs, it provides the most uniform heat transfer to the tubes. Duties are 21 to 132 GJ/h (20 to 125 10 Btu/h) per cell (twin-cell designs are not unusual). 

Von Wiesenthal, P. and Cooper, H. W., Guide to Economics of Fired Heater Design, Chemical Engineering, April 6, 1970, pp. 104-112. 

In such cases, radiant heat transfer is used from the combustion of fuel in a fired heater ox furnace. Sometimes the function is to purely provide heat sometimes the fired heater is also a reactor and provides heat of reaction. The special case of steam generation in a fired heater (a steam boiler) will be dealt with in Chapter 23. Fired heater designs vary according to the function, heating duty, type of fuel and the method of introducing combustion air. However, process furnaces have a number of features in common. A simple design is illustrated in Figure 15.19. The chamber where combustion takes place, the radiant section... 

Process furnace or direct-fired heater Design type, absorbed heat duty, pressure, tube material, capacity... 

TABLE 8.16. Equations and Other Relations for Fired Heater Design... 

Draft should be monitored and maintained as required for the specific fired heater design. Fired heaters without draft control should be periodically checked. 

The fuel typically used in modern fired heater design is natural gas. Fuel heat values are important variables in economic operation of a furnace system. Heat value refers to the known differences in the heat energy released when different fuels burn. Natural gas has a heat value of 909 Btu/ft. ... 

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