27 February 2019

Let’s talk about sustainable aviation fuel safety

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Published in under Aviation

As I travel around talking about Neste MY Renewable Jet Fuel (RJF) in customer meetings and various conferences, one discussion theme always comes up: Safety of RJF.

 How are safety and certification taken care of when it comes to renewable jet fuel?

 Is it as safe as conventional jet fuel?

 Can it cause any operational issues with turbine engines when used?

 Can it be handled and transported in the existing infrastructure for conventional jet fuel?

These are all really valid questions especially when it comes to fuel safety and handling in aviation. Let’s dig a little deeper!

Handling conventional jet fuel quality and certification

Safety is of the utmost priority in aviation, and jet fuel safety plays a large part in this. The American Society for Testing and Materials (ASTM International), is an international standards organization that develops and publishes technical standards for a wide range of products, materials, systems and services. With over 12,500 ASTM standards available globally, the specifications are developed in consensus with the collaboration of industry experts on a voluntary basis.

The globally available commercial jet fuel is certified with an ASTM standard designated as ASTM D1655. There is a committee specifically dedicated that has the responsibility over this standard to ensure fuel quality and safety. This committee is comprised of experts from all over the aviation industry, such as major engine and aircraft OEMs, university researchers, governmental organizations (e.g. FAA), fuel producers, and fuel suppliers.

This committee does not have any mandate to enforce compliance with their standard. The standard has long been seen as a benchmark to ensure quality and mandated in external contracts for fuel procurement worldwide. In fact, a lot of the other fuel standards currently available, such as UK DEFSTAN 91-91, are based on this ASTM standard with minor exceptions.

In order to be used as fuel for commercial aviation, conventional Jet A and A1 have to be certified to ASTM D1655 to meet specific properties, such as density, freezing point and flash point. All jet fuel that is manufactured needs to be sampled many times along the supply chain to ensure that these properties are met. These sample points are at the points of manufacture, transportation, storage and delivery into the aircraft.

All jet fuel that is shipped carries a Certificate of Quality showing compliance to ASTM D1655. Without this certificate the fuel is either rejected or requires recertification. The certification process is generally conducted by in-house or third party laboratories that are certified to use ASTM test methods.

Similarly to conventional jet fuel, all manufactured RJF also has to follow strict sampling and handling procedures. It is important to note that ASTM D1655 does not define quality assurance and handling procedures. Instead, all of these procedures are defined elsewhere; e.g. in ICAO 9977, EI/JIG Standard 1530, JIG 1, JIG 2, API 1543, API 1595, and ATA-103.

What is the case for renewable jet fuel then?

Renewable Jet Fuel has a similar quality specification, designated as ASTM D7566 for the manufacturing of fuel containing synthetic hydrocarbons. This specification governs the properties of RJF and SAF similar to ASTM D1655 for Jet A and A1. The ASTM D7566 specification has been developed over many years following a strict testing regime and approval process deemed to be safe for use in commercial aviation. The specification currently contains five (5) approved pathways to produce a jet fuel containing synthetic hydrocarbons.

Neste MY Renewable Jet Fuel falls under one of these five pathways in the ASTM D7566 Annex A2 production of synthetic hydrocarbon using Hydroprocessed Esters and Fatty Acids, Synthetic Paraffinic Kerosene or the HEFA-SPK process. In this process, triglycerides generally found in waste fats, oils and greases are hydrotreated, isomerized and distilled to produce jet fuel.

Isomerization is a key process when producing RJF as it ensures that a low freezing point can be achieved. Neste MY RJF meets all the properties of the ASTM D7566 Annex A2 when produced. This ensures that the fuel is safe for use as a blending component for fossil jet fuel with up to 50% concentration depending on properties.

In conclusion, Neste MY Renewable Jet Fuel is an ASTM D7566 certified fuel and is safe to be used in flights when blended with conventional jet fuel. All aspects of jet fuel production, certification, blending, handling, and distribution are managed by experienced Neste team along with our respected partners.

Neste’s sustainable aviation fuel meets all the strict safety standards and guidelines for commercial aviation use. Welcome to take off with flights powered by Neste MY Renewable Jet Fuel!