2 replies to this topic

[mido]

hello everyone,  I have some doubt about the normal LEL% (Low explosion limit) on crude oil tank roofs. is it normal to reach 100% LEL reading on the tank roof during production due to tank out breathing. What is the accepted limit for LEL reading? What the safeguards needed in increasing LEL reading. Thanks evey one

[breizh]

Hi mido,

You should review the definition of LEL . I've attached a document to support your work .

note 1: MSDS is the  document to check  to find LEL and UEL .

note 2 :make sure your equipment is regularly calibrated.

Good luck

Breizh 

Edited by breizh, 02 December 2019 - 10:10 PM.

[mido]

Thanks breizh for this valuable reference. I have now good reference for Tanks operation. But i still in debate with my team. The problem is we have a terminal station collect crude oil produced from other sites. the crude should be stabilized in the remote sites. The operators in the terminal say that they smell hydrocarbons above the tank that is in the receiving mode (production tank) and when we go to the roof of the tank with gas detector. the detector read 100% LEL on the tank roof (this means that the ratio of Hydrocarbons reach LEL limit in the tank roof). My opinion that this is normal as in the tank filling PVRV must open and hydrocarbons will release and LEL limit will reach on the tank roof. other personnel say that there is an upset in the upstream facility and this condition is abnormal.Noting that after the tank is closed and there is no movement on it the problem is disappear and hydrocarbons on tank not reached LEL limit.