This study explains how The Nashville International Airport (BNA) removed black powder contamination particulates from jet fuel delivered by a large refined-products pipeline, resulting in improved product quality and reduced filter consumption.
The problem: Off-spec jet fuel delivered from the pipeline required a variety of expensive single-use filters to meet the high-grade cleanliness standard for jet fuel. So, when we stated that our magnetic separator systems would reduce filter consumption and improve fuel quality, the airport fuel facility team decided to put magnetic separation to the test.
The solution: Our team designed a magnetic separator to remove contamination, down to sub-micron sizes, out of ~4,400-barrel batches of jet fuel. The batches of jet fuel are delivered from the pipeline over 3.5-hour periods.
The results: Fluid analysis tests done both upstream and downstream of the magnetic separator showed that it significantly improved the fuel product quality. The airport fuel facility team has noted a significant reduction in the consumption of 5-micron, 3-micron and 0.5-micron filters, with extended use of their clay filters.
We have already noticed a significant reduction in traditional filter use compared to last year based on 2 months of operation.
- Darrel Johnson, GM, Menzies Aviation
The pipeline delivers ~80% of the fuel supply for the Nashville airport. Unfortunately, the pipeline has significant amounts of water in it which degrades the product quality, but more over causes pipe corrosion. This means that pipeline corrosion by-product, black powder contamination, enters the product as it flows to the airport storage tanks. This off-spec product would have to go through extensive filtration to meet the cleanliness requirements of aircraft engines.
When working with clients on fuel applications, we start by discussing their immediate cost challenges associated with filtration. Almost every discussion begins with how to remove sub-micron contamination and water from large volumes of fuel. Most feel stuck with 2 options:
- Accept the costs of going through significant amounts of filters and water separators; and in doing so, accept the associated ongoing exposure and maintenance costs.
- Use higher micron filters that flow the fuel more efficiently, but filter less effectively.
Unfortunately, when dealing with jet fuel, the second option is not an option because finer contaminants can cause premature wear of aircraft engine components. Further, Boeing recently discussed their research into 1-micron sized particulate build up in onboard fuel reservoirs. The article discusses how this particulate could cause poor burn efficiency and impact weight distribution of planes.
After discussion with the airport’s fuel facility team, our team was confident a magnetic separator system would solve their issues.
- Our systems employ our patented design that uses magnetic fields to capture contaminants down to sub-micron sizes.
- They are specifically designed to meet application flow volume and pressure.
- They are cleanable which means minimal consumable costs.
A unique benefit of magnetic separator elements is that they catch non-magnetic particulate via the principals of static adhesion and cross contamination. Read this article for an explanation. In this application however, the majority of the contamination in the fuel coming from the pipeline is black powder consisting of iron sulfides and iron oxides. Given that iron is extremely magnetic, we could comfortably guarantee that our magnetic separator system would catch 95+% of the contaminants in the fuel. Check out our technical specifications for an explanation on how we can make that guarantee.
We initially ran a test using one of our sample stations on a jet-fuel slip stream, and with successful results, the Nashville airport operators were ready to deploy a full-size system. This system is the first line of defensive for removing particulate contamination. It is installed before the storage tanks which are upstream of the various other filter systems: the 5-, 3- and 0.5-micron filters, water separators and clay filters that are deployed before and on filter carts used to load fuel onto the aircrafts.
- This magnetic separator system processes on average 4,400-barrel batches that are delivered from the pipeline over 3.5-hour periods.
- This unit has a magnetic element array capable of holding up to 450 lbs of contamination before cleaning is required - think of the cost savings on maintenance alone.
The magnetic separator was installed early December 2019. The success of this deployment would be determined by a decrease in filter consumption. As such, the system was cleaned shortly after installation so we could run some tests on captured contamination. Tests indicated that the system was ideal for this fuel application.
- 20% of the contamination was at or under 1 micron in size.
- The median particle size was 37 microns (around the size of a hair follicle).
- The 0.8 micron Millipore patch tests* done both upstream and downstream of the magnetic separator indicated a significant improvement in product quality and cleanliness.
We determined that based on the size of the unit and the volume of fuel, 4-month cleaning cycles would be ideal. Given that our systems have such high holding capacities, we usually use slight changes in the pressure differential to determine cleaning cycles. Since installation, our system has not registered a change in pressure differential.
Expertise in reducing maintenance
Our world has been flipped upside down with no clear indication that our industry will be operating regularly anytime soon. Our systems offer a solution to minimized human exposure through reduced filter changeouts across midstream facilities, refineries and other end users like the Nashville International Airport.
If you’re curious but not sure where the best magnetic separator deployment would be in your facility, take a read through this presentation on how a 200,000 bbd+ refinery tested one of our magnetic separator sample stations throughout their facility. They tested the system on a hydrodesulfurization (HDS) unit amine system, the vacuum gasoil feed into the HDS unit, 2 separate furnace fuel gas systems, and a turbo compressor lube system in the fuel complex. Since the testing, the refinery is proceeding with permanent installations on 3 separate crude streams, a VGO feed stream, a combined VGO/LGO/MGO/HGO feed stream, the amine system in the HDS unit, and a fuel gas system in the hydrocracker and other fuel gas streams.