What is the recommended safe distance from an oil fired heater and a storage vessel of volatile hydrocarbons mixture (2000 m3 of Dripolene with a floating roof) or where can I find such recommendations.
You need a Quantitative Risk Analysis in order to know all credible scenaries in your plant.
The Quantitative Risk Analysis consists in a systematical evaluation of the facilities, in order to identify any potentially dangerous event and to estimate the damages to exisiting facilities and third as consequences of escapes of toxic, inflammable and combustible substances, for like that to be able to quantify the level of implied risk by means of the estimation of the frequency of occurrence and of the magnitude of his consequences.
We have subcontracted specializing companies in risk analysis when we have needed locate new equipments or facilities for our oil production plant. According with our standard is mandatory to do a risk analys in this situations.
There are some safety standards avialble such as the oil industry safety directorate ( OISD) which say that the safe distance between heatetr and class A storage tank ( flash point below 23 deg centigrade) should be atlest 90 meters.
"Heaters are always located at a safe distance 15 meters away from other hydrocarbon bearing equipment and preferably upwind; however, on some process it is permitted for reactors to be within this distance to prevent light volatile vapors from begin blown towards an open flame.
Space must be allowed for tube replacement for both horizontal and vertical heaters and this, together with ample access for mobile equipment, should be considered on piping layouts and drawings. Ample access is always needed for firefighting equipment with areas under or around heaters usually paved and curbed.
No low points in the paving or grading are permitted as these provide excellent sports for trapping hydrocarbon liquids which could be ignited by the open flames of the burners."
As I recall, the insurance people also may have a requirement for spacing on fired heaters.
With regard to storage tanks with Class I flamable liquids, NFPA-30 contains spacing requirements to other tanks, occupied buildings, property lines etc...
Please complete this thread and let us know what you decide ....
Usually 15meter is provided between tanks' shell to boundary wall for Class I flammable liquid.
For fire heaters, usually lay down area for replacement of internal coils are usually provided for maintenance activities and crane accessibility & movement.
If we have other pressure vessels in the radius of 15 m from fired heater, what should we do? Should we consider to insulate the adjacent vessels for increasing the flame resistance during fire case? Please comment.
Either providing fire resistance material for the vessels or provide deluge system to cool down the exposed vessel(s) by fire water with spray nozzles in around piping.