Page 23 - Microsoft Word - Sulfo and Sulfa 1.doc

followed by an SO water cooled heat exchanger. The inlet mist eliminator removes
3
traces of sulfuric acid or oleum from the cooled SO gas stream. Heat recovered from the
3
second to third pass converter interstage cooler and SO cooler regenerates the air dryers,
3
eliminating the need for an external heat source. Heat recovered from the SO and first to
2
second pass interstage cooler can be used to generate steam in the optional heat recovery
system. In state of the art sulfonation plants, computer aided hot gas piping design
eliminates troublesome hot gas expansion joints in the gas plant. The enhanced piping
design improves significantly plant reliability and eliminates a possible source of
inadvertent SO or SO discharge to the environment.
2
3
An inline double pipe ignition air heater warms the combustion air stream for sulfur
burner preheating and ignition. A gas-fired duct type start-up heater in the
regeneration/utility air line preheats the SO and first to second pass interstage cooler.
3
The start-up heater, used during a cold plant start-up, reduces to less than

Figure 22. SO 3 Gas Generator

ATOMIZING AIR

SULFUR SULFUR
BURNER

IGNITION AIR
HEATER
CONVERTER

REGENERATION/
CWS UTILITY AIR
INLET MIST
PROCESS ELIMINATOR
AIR

CWR
CASCADE COOLER

Page 22 of 36 © 1997 The Chemithon Corporation