For more than seven decades, Lummus Technology has been designing and supplying furnaces for delayed coking projects. These projects have ranged from small single heaters to the current multi-heater installations with air preheat systems. Early heater designs were the single-fired type, but since 1998 they have been changed to Lummus double-fired designs for shorter residence time and longer run-length. The heaters have been both gas and combination gas/oil fired. CB&I’s delayed coking heaters have handled a wide range of feedstocks in refineries and upgraders for both fuel and specialty coke production mode of operations.
All Lummus Technology fired heater designs come with the capability for on-line spalling. This feature allows spalling of the heater coil that has reached its limits of tube metal temperature while the other coils remain in hydrocarbon service. The current designs, working in cooperation with Chevron Lummus Global’s delayed coking technology team, incorporate multiple cabins with single coils allowing superior individual firing and temperature control.
Lummus Technology also designs delayed coking heaters with a unique configuration that allows isolation of individual coils or cabins for mechanical decoking (pigging) of the heater tubes while the unit is kept on-line. This provides for maximum on-stream time. The heaters are designed with air preheat to provide the highest possible thermal efficiencies while still meeting the plant’s emission requirements. Best available control technologies are utilized to comply with the most stringent air quality standards.