Designing and manufacturing a big heater to fit a small space was challenge enough. But there were other challenges too. That’s what Heatec faced recently when producing a heater for a gas processing facility in Long Beach, California.
The gas processing facility is owned and operated by the Thums Long Beach Company (Thumsco), a private company. The heater is to be used to remove CO2 in treatment of natural gas.
The heater needed a very small footprint to fit available space (14 x 15 feet). However, it could be as tall as needed. This called for an up-fired vertical heater with a careful arrangement of access platforms, pumps, piping, expansion tank, controls, etc.
Other challenges had to do with limits on emissions, safe operation in an explosive atmosphere, ability to withstand an earthquake, need for high thermal efficiency, and ability to resist corrosion.
Emissions within allowable limits was achieved by use of a Bloom Series 1530 ultra low NOX burner. Its NOX emissions are no more than 20 ppm throughout a required 4 to1 turn-down.
Safe operation is assured by strict quality control and use of components that meet the requirements of Class I, Div 2, Group C & D as defined by NFPA 496. A major concern is the welded joints of the helical coil inside the heater. Thermal fluid (Therminol 55) is heated to 450 degrees F as it flows through the coil. So all weld-joints of the helical coil were X-rayed to make sure there are no flaws that might allow leaks and cause a fire. The heater is also designed structurally to meet requirements of a Seismic 4 earthquake zone.
High thermal efficiency is achieved by a convection section built into its exhaust stack. It recovers heat from the flue gases and uses it to preheat the thermal fluid. It boosts thermal efficiency of the heater to 90 percent. (To read more about boosting themal efficiency with a stack heat exchanger, read this article published by Process Heating.)
Corrosion resistance on external surfaces was achieved by seal welding and use of special paints: high-durability Carbozinc 11 primer, Carboguard 890 mid-coat and Carbothane 134HG top-coat. Ladders and platforms are galvanized. The inside of the heater shell is coated with a special asphaltic material that resists highly corrosive condensate.
Heatec, located in Chattanooga, Tennessee, is a major manufacturer of industrial heaters.
