Study of the Effect of Hydrocarbon Type Biodegradation on Fuel Specification Properties.

摘要

The USAF is promoting initiatives such as the AF Smart Operations for the 21st Century (AFSO21) to maximize value and minimize waste. At the same time, the 2014 Energy Action Plan (2014 EAP) describes that the majority of the energy requirements for USAF operation is aviation fuel and that we need to assure its supply, reduce risks and improve resiliency by being prepared for multiple disruption scenarios; fuel biodeterioration may be one of those scenarios. In accordance to AFSO21, the AF Petroleum Agency and the Defense Logistics Agency have approved the reduction of fuel icing inhibitor (FSII) diethylene glycol monomethyl ether (DiEGME) in JP-8 fuel from 0.10 0.15% to 0.07 0.10% and they are in the process of moving to commercial Jet A (with additives). In the past, the transition from more toxic fuels and additives (JP-4 and ethylene glycol monomethyl ether - EGME) to less toxic ones (JP-8 and DiEGME) contributed to increased biodeterioration incidents. Reduction of FSII could further exacerbate fuel biodeterioration. More importantly, FSII doesn t protect against microbial growth happening at the fuel phase and headspace of the tank where fuel probes are typically placed. Tests performed in our laboratory showed that biodeterioration of materials in the fuel phase can occur even when the fuel itself appeared clean. Multiple field cases have indicated the occurrence of biodegradation of jet fuel filters and jet fuel bladder materials. Some costly problems associated with microbial growth include tank corrosion, fuel pump failures, filter plugging, injector fouling, topcoat peeling, and engine damage. Additionally, military ground vehicles, ships and power generators that use diesel fuel are very susceptible to biodegradation and biocorrosion issues due to the lack of FSII and the higher level of impurities in diesel which may enhance microbial growth.