by Dennis A. Teefy
Maintaining tactical vehicles is an essential
part of ensuring the overall readiness of the military. Tactical
vehicles are unique among Army equipment in that they are periodically
stored for extended periods of time with full fuel cells. In many
instances, the fuel in the stored vehicles becomes contaminated
with biota, dirt, and water. The costs associated with handling
contaminated fuel, along with the Army's move toward a "single
fuel on the battlefield" concept, prompted Army users to
ask the U.S. Army Environmental Center (USAEC) at Aberdeen Proving
Ground, Maryland, to develop a way to reduce, recycle, or reuse
certain fluids used in Army vehicles.
In response to this request, the USAEC, in cooperation
with the Fuels and Lubricants Technology Team (FLTT) at Fort Belvoir,
Virginia, developed a fluid recycling program. The program is
divided into two projects that concentrate on reducing the used
fluid waste-recycling and decontamination.
The first project deals with recycling of fire-resistant hydraulic fluid (FRH). FRH is used in a wide variety of military vehicles. Like all other vehicular fluids, it must be replaced periodically. The FRH drained from vehicles is contaminated with particulates and water. Currently, this fluid is disposed of as a hazardous waste. Numerous mandates to reduce hazardous waste, ensure proper vehicle maintenance, and reduce high procurement costs make recycling of FRH highly desirable.
The Army Tank-automotive and Armaments Command Mobility Technology Center at Fort Belvoir conducted a 2-year evaluation of the viability of recycling military-specification FRH. The results of the study showed that FRH may be reused if it is mixed with at least 25 percent new fluid.
Armed with those results, the FLTT kicked off 6-month field demonstrations at Fort Carson, Colorado; Anniston Army Depot, Alabama; and Fort Hood, Texas. Seven commercial recycling units were tested to evaluate their ability to meet specification cleanliness requirements. Four of the units proved capable of removing water and particulates to a level below the military specification.
The field demonstrations of the FRH recyclers revealed
a need to make the recyclers more user-friendly and cost-efficient.
As a result, in-line moisture and particulate monitors will be
added to provide real-time data on contaminant concentration.
The USAEC and FLTT are working to reach agreements with the manufacturers
of the FRH recyclers to provide the technology for in-line monitoring.
USAEC, FLTT, and U.S. Army Aberdeen Test Center (USATC) are seeking
opportunities to implement and expand the recycling of FRH.
The other promising project coming from the fluid recycling program is the fuel filtration/additive unit (FAU). The need for this unit emerged because vehicle fuel cells become contaminated by free water, dirt, and biota. The contaminants rapidly plug the fuel filters and disable the vehicle, decreasing the vehicle's combat readiness. The current method of decontaminating the vehicle fuel cell is difficult, extremely labor intensive, and removes the vehicle from service for a period of time.
The FAU is a system of off-the-shelf technologies that decontaminate fuels and inject chemical additives. The Belvoir Fuels and Lubricants Research Facility at the Southwest Research Institute in San Antonio, Texas, developed, designed, and built the FAU. The fuel decontamination rate is a rapid 60 gallons per minute. The unit is mounted on a 5-ton trailer for maximum mobility and easy shipment. There is no need for external power, so the unit can operate independently in most environments. The FAU removes the fuel from the fuel cells and storage tanks of ground vehicles, separates the water and particles from the fuel, and then refuels the vehicle with the cleaned product.
An added feature of the FAU is its ability to inject up to four additives into fuel simultaneously. These additives can be used to convert jet A-1 fuel to JP-8 fuel, combat microbial growth, prevent free water accumulation, and stabilize the fuel.
By recycling the contaminated fuel, the FAU eliminates the need to dispose of it as a hazardous waste. The quick decontamination of fuel in vehicle fuel cells increases combat readiness and decreases valuable labor hours. The injection of additives makes it easy to adapt the fuel to any environment.
The FAU has proven effective in a variety of field situations. At Fort Stewart, Georgia, the FAU was set up to remove a heavy concentration of water and particulate contamination from 243 vehicles. At Twenty-Nine Palms and Camp Pendleton Marine Corps Bases, California, the particulate matter found in fuel was finer than that at Fort Stewart because the fuel oil additive portion of MIL-S-53021 had been added to vehicle engines. The FAU was used to remove the minute particles, which corrected the fuel filter plugging problem. Additional tests were conducted at Blount Island, Florida. All of the users at the test sites were enthusiastic about the performance of the FAU.
The FAU can provide significant economic savings
while preventing pollution. Its design is flexible and can be
altered easily to adapt to individual installation needs. The
prototype FAU has been shipped to Fort Knox, Kentucky, for a cost
and operation field demonstration. USAEC and USATC are working
in conjunction with Fort Knox to determine the cost effectiveness
of the FAU and design a decision tree that will help users gauge
the FAU's applicability to their own installations.
The recycling of FRH will be a great aid in the maintenance of military vehicles. The recyclers will help extend the life span of the FRH, which will decrease procurement costs and keep the vehicles running at optimum performance. The time previously devoted to hazardous waste disposal and handling can be spent on maintenance efforts. Reducing particulates and water in FRH will allow it to function as it was designed.
The FAU will have a dramatic impact on the readiness of our mechanized troops as well. Because the FAU will mitigate the fuel filter plugging problem, vehicles can be held at a higher state of readiness. In the case of fuel contamination emergencies, the FAU can decontaminate large quantities of fuel quickly and safely. The additive system will allow fuels to be converted rapidly to different grades.
Fewer man-hours will be spent in the motor pool removing vehicle fuel cells, changing filters, and disposing of contaminated fuel. When fuel is decontaminated, it no longer has to be disposed of as a hazardous waste but can be reused instead. In addition, the procurement cost of the fuel is recovered.
The USATC and USAEC are soliciting Army users who
are interested in procuring the FAU or FRH recycling units. Potential
users are being queried through the Defense Environmental Network
Information Exchange (DENIX). For more information, contact Dennis
Teefy of the USAEC Environmental Technology Division at (410)
612-6860. His e-mail address is t2hotline@aec2.apgea.army.mil.
ALOG
Dennis A. Teefy is an environmental scientist at USAEC. He has a bachelor's degree in agriculture from West Virginia University. His fluid recycling research was supported in part by an appointment to the Postgraduate Environmental Management Participation Program at USAEC, which is administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and USAEC.