Incident Report

Subject:                  RE: Crude Tank - Roof Problem      

Date of first enquiry:        Mon 06/01/2003 17:32                    

Initial enquiry / comment.

I have a crude oil floating roof tank problem. Pls pass on to others who might be able to help. Problem: Suspect one or more of severalp ontoons holding up the roof is leaking. This has led to crude oil surfacing to above the roof.

Immediate measures taken: We use an air-operated pump top eriodically pump off the oil from the roof via the roof drain outlet back into the tank. However the "leaking" oil keeps re-surfacing on to the roof.

Question: Does anyone know of any preventive measures that can be taken to prevent the oil on the roof to be ignited by lightning ? The oil on the< /SPAN>roof appears in patches but tend to move towards the roof centre. With our tropical thunderstorms, the threat of a lightning strike on the hydrocarbon vapour is always there. We are looking for temporary measures until we can decommission the tank to repair the leaky pontoon. Are there chemicals that can be sprayed on to the roof deck to prevent this ? Foam is a possibility but we all know that foam degrades and goes off after a while.

Regards,

Responses:

Date

Detail

Documents

 Mon 06/01/2003

I am not familiar of any quick fix but I will ask around. I would treat any potential fire in the tank and protect for fully involved. The below photo was a fire that I attended in Nigeria, 270 foot crude oil, which began as a seal fire but rapidly escalated to fully involvement due mainly to product on the roof. Another issue that we have witnessed when vapor in the pontoons are in the flammable range and explosions occur is the potential of the roof fragmenting and jeopardizing other tanks and remaining portions of the roof penetrating the floor of the tank causing uncontrollable product dump.