The 2013 February/March edition of Ramp Equipment News (GHI’s sister publication) included an article entitled “Air Today and Tomorrow”, which focused on the use of forced air technology in deicing trucks. This new technology offered users the ability to remove contaminates in a more cost-efficient way.
In the last 10 years, the deicing industry has experienced a lot of change and innovation, which has greatly improved our ability to manage fluid more efficiently. In 2013, the EPA announced a requirement to reduce glycol on the ground at airports by 65%. This mandate was to become effective in 2015.
Deicing truck manufacturers developed technology for onboard fluid blending, allowing deicers to spray aircraft with the most efficient fluid blend for the conditions.
Two major US carriers, at Dallas-Fort Worth Airport, invested in blending cube systems to reduce glycol consumption by custom blending deicing fluid to meet the freeze point requirement of the outside air temperature. Custom blending is accomplished either onboard the deicing equipment or with the use of a blending cube and is a decision specific to each operation.
Jef Gaskill from Liquid Automation Systems is one of the leading manufacturers of blending cubes and fluid dispensing systems.
“LAS is focusing on the reliability of fluid management at locations with mixed fleets. Blending cubes reduce operational costs, mitigate risk of cancelled flights due to fluid supply, and significantly reduces the amount of glycol on the ground,” he said.
Global events have also had an impact. In early 2020, the pandemic dramatically disrupted the aviation industry, including an increase in demand for products made with propylene glycol (PG), a key component of deicing fluid. This demand began to put pressure on PG supply, making it a more valuable commodity. Stress on truck and rail delivery systems increased lead times for product delivery.
In 2021, the Texas and Louisiana Gulf Coast were impacted by an unprecedented freeze event which halted production of propylene oxide and propylene glycol, further impacting PG supply and pricing. Deicing fluid prices reached the highest seen in recent times at the start of the 2022–2023 deicing season.
Fluid management today
Events over the last decade have pushed to the forefront technology and systems that have been developed to collect, recycle, and reuse glycol for a more sustainable and environmentally-friendly system.
Many airlines and service providers use blend-to-temperature technology to spray the most efficient mix of fluid on aircraft. Integrated Deicing Services (IDS), a leader in aircraft deicing services, uses blending cube technology and trucks with onboard blending technology, along with its refined program management approach to deliver the most cost-efficient use of deicing fluid.
According to Dan Young, Vice President of Sales & Customer Relations at IDS, “IDS only uses forced air deicing trucks with enclosed baskets at all of our operations. Our precise methods for the application of fluid, along with the utilisation of the most current technology and blending, minimises the amount of fluid used per event. This entire process underscores our commitment to health, safety, and environmental stewardship.”
Many airports and centralised deicing facilities use passive collection, active collection, or a mix of both to collect spent aircraft deicing fluids.
A passive collection system includes catch basins, trench drains, vaults, pumps, and storage tanks. The spent fluid enters the tanks at a slower rate and with a lower glycol concentration, driven by ramp sloping funneling fluid to the drains.
Active collection utilises Glycol Recovery Units (GRUs) to recover the spent aircraft deicing fluid from the immediate deicing area. This action allows for the capture of spent fluid with a higher concentration of glycol. These units actively collect spent fluid, when it is safe to do so, in deicing areas after the fluid is applied to aircraft. Active collection requires coordination with deicing operations in order to collect fluid with minimal impact to airport operations.
Brian Leuck, Vice President of Operations at Inland Technologies International knows that each operation requires a unique solution. “Inland Technologies works with our customers to understand their specific needs, whether they are water-quality driven or part of an overall sustainability initiative, and tailors a system to achieve the customer’s goal. There are a variety of collection actions that could be taken: passive, active, or a combination of both. This decision is typically a collaborated effort between the airport, airline customers, operation partners and Inland Technologies.”
The type of collection selected is truly site specific and is based on your infrastructure, plus what you need or want to collect.
After fluid is collected and stored, in either in-ground or above-ground storage tanks, the recovered fluid can be discharged through publicly-owned treatment works or processed to remove glycol from the affluent. By recycling the glycol, it can be refined into a reusable glycol product that can be sold for industrial use, or further refined into SAE AMS 1424 Type I aircraft deicing fluid produced using 100 percent recycled glycol.
Inland Technologies started recovering SADF in mid-1990s and to date has collected and managed over 500 million gallons of stormwater for our customers. Inland Technologies leads the industry in collection and recycling of glycol using their patented mechanical vapour recompression system and distillation equipment.
Leuck is very familiar with the required technology and benefits of implementing an effective closed-loop system.
“At Inland Technologies, we utilise patented processes for separating glycol from water. The separated water is safely discharged to the sanitary sewer; the reclaimed glycol is further processed into industrial-grade glycol product or recycled through our closed-loop system to an approved SAE AMS Type I ADF.”
“We start the recycling process with glycol concentrations ranging from 2% to 3%. If we are on the lower end of the concentration spectrum, we will run the material through our glycol concentrator to produce a 50/50 mixture of glycol and water. This material is shipped to our processing facility in Portland, Maine, which in 2016, became the first on-airport facility in the US to capture, recycle, and remanufacture an AMS 1424 Type I ADF.”
Inland Fluids is the only company to provide Type I aircraft deicing fluid made with 100% recycled glycol at 14 locations in the US, three locations in Canada and five third-party customers. Inland Technologies’ recovery and recycling operations have grown to 22 airports world-wide.
Brandy Pace, Director of Inland Fluids, a division of Inland Technologies, manages planning, blending, supply, logistics, product technical support, coordination and customer service for all glycol products. She has 20 years of experience in both the chemical and logistics industry, and understands recycled glycol production and delivery end-to-end.
“Starting over 10 years ago, Inland Technologies recognised the opportunity of producing aircraft deicing fluid from a feedstock produced from the collected SADF. We began working with toll blenders to take our 99% pure glycol and produce an approved SAE AMS 1424 Type I Aircraft Deicing Fluid. In 2016, we began producing ADF in-house, and have now expanded operations to three facilities including Calgary International Airport and, our newest operation, Denver International Airport (September 2023). Inland Technologies produces both ethylene glycol-based and propylene glycol-based fluid products. We work with strategically located toll blenders to efficiently provide product to all our customers.”
Closed-loop system continues
A closed-loop system for the efficient and cost-effective recovery, recycling and manufacturing of aircraft deicing fluid provides significant benefits for airlines, service providers, airports, and the environment, and requires a proven provider. Airlines and service providers see a cost savings in deicing fluid and reduce strain on their glycol supply. Airports that collect and recycle spent deicing fluids release less glycol into the environment, reduce pressure on their glycol supply, and reduce wastewater discharge fees resulting in meaningful cost savings.
Aircraft deicing fluid manufacturers that use recycled glycol are taking a commodity that was previously discarded into the environment and turning it back into a valuable, sustainable and commercially viable product for reuse or resale.
I know we are all interested in seeing how technology evolves in the next decade.
