3 replies to this topic

[Renier]

We have had some complaints regarding the odors emanating from our Fuel Oil tanks. The oil is a 180 cSt product stored in a cone roof heated tank (dia=31m height=14m) at 60°C with approximately 16 tank turnovers per year. The options I am considering is to use Sulfatreat (iron oxide) or Activated carbon to treat the vent. I was also asked a question about the feasibility of installing an internal floating roof in the tank.

A few questions I have:

- My understanding is that floating roofs are not normally used on fuel oil tanks as the vapor pressure is very low and there would be some risk of wax build up on the roof seal. I however could not found any literature references with actual operational experience to confirm this. Is there anyone out there who has tried to store a residual fuel oil in an internal floating roof tank. My perception is that the retrofit cost would be prohibitively high.
- Sulfatreat seems to assume all odors are due to the sulfur components in the fuel oil and I am not sure that it would be capable of dealing with the heavier sulfurcontaining compounds. Does anyone have some operational experience in treating odours from asphalt or fuel oil tanks using sulfatreat/iron oxide. If so how effective is it in dealing with odors?
- I have used a portable PID detector to measure the VOC content in the vent and I found readings in excess of 1000 ppm. My calculations show that I should be able to size a vessel with satisfactory change-out frequency even though I have a weight limitation for installing it on the roof. I have however assumed a absorption capacity of around 15% w/w but I understand the higher temperature will have a negative impact on that capacity. Does anyone have an idea to what extent the capacity would be reduced? If anyone has some experience in using Activated Carbon in this service I would appreciate it if they could share their operational experience.

Thank You.

[JMW]

You might try contacting CBI Engineering Denmark.
They are experienced with Bunker fuels and produce an activated charcoal vent filter.
http://www.cbi.dk/environment.html

[Renier]

You might try contacting CBI Engineering Denmark.
They are experienced with Bunker fuels and produce an activated charcoal vent filter.
http://www.cbi.dk/environment.html

Thanks, I will do that.

[kkala]

We have had some complaints regarding the odors emanating from our Fuel Oil tanks. The oil is a 180 cSt product stored in a cone roof heated tank (dia=31m height=14m) at 60°C with approximately 16 tank turnovers per year. The options I am considering is to use Sulfatreat (iron oxide) or Activated carbon to treat the vent. I was also asked a question about the feasibility of installing an internal floating roof in the tank.
A few questions I have:

- My understanding is that floating roofs are not normally used on fuel oil tanks as the vapor pressure is very low and there would be some risk of wax build up on the roof seal. I however could not find any literature references with actual operational experience to confirm this.
Same experience for me, when dealing with heavy (black)slop storage in 2007. I had the impression that the liquid could even get like gum in the roof seal, due to poor heating.
However the Refinery said they had successfully stored black petroleum products in floating roof tanks. Compared to light product FR (floating roof) tanks, they asked for a scraper in addition, understood to be located beneath the FR (attached to it). Project was then interrupted, so we could not see details of the implemented installation.
Is there anyone out there who has tried to store a residual fuel oil in an internal floating roof tank. My perception is that the retrofit cost would be prohibitively high.
No experience. Concerning mentioned tank of 2007, there was a thought for internal floating roof, soon rejected without detailed investigation.
- Sulfatreat seems to assume all odors are due to the sulfur components in the fuel oil and I am not sure that it would be capable of dealing with the heavier sulfur containing compounds. Does anyone have some operational experience in treating odours from asphalt or fuel oil tanks using sulfatreat/iron oxide. If so how effective is it in dealing with odors?
No experience.
- I have used a portable PID detector to measure the VOC content in the vent and I found readings in excess of 1000 ppm. My calculations show that I should be able to size a vessel with satisfactory change-out frequency even though I have a weight limitation for installing it on the roof. I have however assumed an absorption capacity of around 15% w/w but I understand the higher temperature will have a negative impact on that capacity. Does anyone have an idea to what extent the capacity would be reduced? If anyone has some experience in using Activated Carbon in this service I would appreciate it if they could share their operational experience.
No personal experience, but about 10 years ago I had followed a presentation of an American company (Calgon??) dealing with retention of VOCs before escaping to Atmosphere. They supplied the whole installation, not only the activated carbon, and could clarify your query, if contacted. See http://www.vaporreco...p?page=ilta951'> http://www.vaporrecovery.com/index.php?page=ilta951 and http://www.eptq.com/...25-d913d07650b9 for some general info.
CBI (mentioned by JMW)is also known here for their catalysts in Refinery Sulphur recovery units (Claus unit gases upstream incinerator).
(Note: Last query is believed to be applicable for cone roof tanks only.)

Edited by kkala, 05 June 2011 - 12:35 AM.