With bio fuels being used more widely than ever and petrol now increasing to a mandatory 10% bio content, we are being asked if diesel fire pumps can be operated on 100% biodiesel or diesel fuel with any bio content.
Biodiesel fuel specifications vary dramatically, both in terms of blend concentration (% biodiesel compared to % petroleum diesel [B1 – B100]) and in terms of the chemical properties of the underlying esters used in their manufacture. For this reason, there is no simple yes or no answer to such requests.
For guidance we will always refer to the manufacturer fuel requirements who only recommend that their engines are operated using No. 2-D S15 Diesel Fuel conforming to ASTM International D-975 or British Standard BS2869 (fuel oils for agricultural, domestic and industrial engines and boilers specification). Therefore, 100% petroleum fuel shall be used whenever possible.
In addition to the requirements of the manufacturers we must also highlight the position taken within the “NFPA 20 Standard for the Installation of Stationary Pumps for Fire Protection”:
“A.126.96.36.199 Biodiesel and other alternative fuels are not recommended for diesel engines used for fire protection because of the unknown storage life issues. It is recommended that these engines use only petroleum fuels.”
Common industry concerns relating to the use of biodiesel within emergency standby service diesel fire pumps include, but are not limited to:
- Long-term storage stability issues of biodiesel fuels. (Anticipated low operation hours)
- Reduced engine power output potentially preventing the driver from operating the fire pump at the maximum duty design point. (Biodiesel often has a reduced cetane rating compared to 100% petroleum based diesel fuels)
- NFPA 25 and the engine manufacturers driver maintenance schedules may not be sufficient to prevent adverse product performance. (Biodiesel increases the incidence of fuel filter clogging, oil contamination and rubber hose degradation) If you have any additional questions in relation to application of biodiesel within diesel fire pump drivers please contact [email protected]