PurdueGuy,
I'm sorry, I should have been more clear, the storage tanks are both open to atmosphere. They do not have PV vents. And the tanks are 4,050 long tons (608,000USGAL), not 40,050 long tons.
Additional information - Our sulfur has H2S. We figure that we may have a buildup of pyrophoric...
We are a Refinery/Upgrader in Regina, Saskatchewan, Canada. We currently have 2 - 608,000USGAL (40050 long tons) liquid sulfur storage tanks that are 95' diameter by 14' high. Each tank is vented to atmosphere through two 10" steam jacketed roof vents spaced 5' apart on the outer perimeter...