Why We Need Bundpourers for Storage Tank Farms?
Dyke fires are often caused by leaking flanges or valves at the base of tanks, damaged or cracked pipework, and sometimes because of spills as a result of maintenance work. Fighting fires due to dyke area hydrocarbon spill fires in a conventional manner using fire fighting branches and fixed monitors have the following distinct disadvantages
- Fire-fighters may have to enter the dyke to apply foam to the fire thereby putting themselves at risk
- Monitor application can be too forceful, plunging the foam into the burning fuel causing fuel/foam mixing, or splashing the fire over other areas
- Low expansion foam is slow to cover large areas to a sufficient depth compared with a medium expansion foam blanket
What are Bund Pourers?
Bund Pourers are Fixed Type Medium Expansion Foam generators installed permanently above the dyke wall of Storage tanks for fire fighting during Dyke fires.
Bund pourers come in different flow rates ranging from 400 lpm up to 1800 lpm at an inlet pressure of 2-7 bar. It is usually installed above the dyke walls by anchor bolts. Foam solution can be fed to bund pourer from foam tenders through delivery hose using 63 mm instantaneous male coupling fitted in the equipment.
It is mandatory to have bundpourers installed for Class A product tank areas for fire fighting as per Oil Industry Safety Directorate (OISD) standards.
What is Class A Product?
Petroleum Class A means petroleum having a flashpoint below 23 degrees Celsius. Eg: Naphtha, Gasoline, Toluene, Benzene, Hexane. Methanol, Ethanol (Ethyl Alcohol), Ethyl Acetate, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, Acetone…etc
Is it a requirement by standard?
As per the latest revision (Oct 2017) of OISD-STD-117 Fire Protection Facilities for Petroleum deports, terminals, Pipeline installations, and Lube Oil installations (Clause No.4.4.7), fixed type Medium expansion foam generators shall be provided for fire fighting in dyke area in case of Class A products to arrest vapour cloud formation from spilled volatile hydrocarbons.
2 nos. Fixed-type foam generators for each tank dyke need to be installed. OISD 117 mandates that Medium expansion foam generators shall be provided for fire fighting in existing facilities also whereas for new/upcoming locations it shall be implemented along with commissioning of the facilities.
Similarly OISD 116: Fire Protection Facilities for Petroleum Refineries & Oil/Gas Processing plants (Oct 2017 edition) narrates the same requirement too….