Dear 6748,
I forgot one more area:
How about you sulfur gun / nozzle assembly?? Isn't is steam jacketted? you can have a leak there??
Please RUN to the plant & find the real culprit
All the Best
Dear 6748,
I presume it is a sulfuric acid plant.
How sure are you about the moisture content of air from dryer?
Is air supply through a drying tower, using 98 % sulfuric acid for drying the air???
If you are sure about moisture content.... >>> then ... is there acid mist carry over???
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