PTQ Q2 2024 Issue

SAF production via co-processing in the kerosene hydrotreater

Guide to co-processing for SAF production, covering relevant regulations, why kerosene hydrotreaters are preferred, and addressing challenges with solutions

Maria J L Perez, Gitte Thomsen Nygaard and Sylvain Verdier Topsoe

S ustainable aviation fuels (SAF) have been at the fore- front of the fuel industry’s agenda for several years, with increasing attention driven largely by regulatory pressures. Across the globe, from the European Union and the UK to Japan, Brazil, India, and Singapore, SAF man- dates are being implemented, sometimes accompanied by significant penalties for non-compliance, as exemplified by the ReFuelEU aviation initiatives. These mandates are set to significantly accelerate the deployment of SAF produc - tion, and projections indicate that bolstered by such meas- ures, SAF production could reach approximately 13 million tons by 2030 and potentially soar to around 120 million tons by 2050. 1 Simultaneously, regulators are incentivising SAF supply through attractive credit schemes. In the US, SAF suppliers can benefit from Renewable Identification Number (RIN) credits, Low Carbon Fuel Standard (LCFS) credits, Inflation Reduction Act (IRA) production tax credits, and state-based credits from states like Washington, Minnesota, and Illinois. However, there are significant challenges to over - come to increase the supply of SAF. Production of SAF in standalone plants is capital intensive, and the process of revamping an existing unit or constructing a new one can span several years. This is where co-processing in a ker- osene hydrotreater presents a compelling alternative. Not only is it a low-capital expenditure (Capex) approach, but it also allows for the rapid deployment of SAF production within a few months (given the right conditions). With more than 50 cycles of units co-processing renewa- ble feedstocks in various hydroprocessing units worldwide and with a wide range of renewable feedstocks, Topsoe has accumulated extensive experience in this field. This article is intended to offer a starting guide to anyone considering going down the co-processing path by comprehensively covering the regulations to be aware of, why co-processing in the kerosene hydrotreater is the preferred choice for SAF production, and the challenges and solutions. What is co-processing? In co-processing, even small amounts of fossil feedstock, such as crude oil, can be replaced with renewable feed- stock, such as vegetable oil, animal fat, and used cooking oil (UCO). These are processed together in the hydrotreater

or hydrocracker (for example) to produce renewable fuel. Co-processing of renewable feedstocks, such as virgin oils or waste oils and fats, in hydroprocessing units has been common practice for over a decade, primarily to produce renewable diesel. The amount of renewable feedstock added is typically at relatively low levels of less than 5%. Such a low ratio gen- erally only necessitates a catalyst change, which makes the process relatively straightforward and makes co-process- ing a simpler alternative to major revamps. In cases where the co-processing ratio is increased to 10% or higher, revamps are typically required to address common challenges, such as managing high exotherms or mitigating corrosion issues. 2 As written in the first quarter of 2024, most refineries in the EU have become familiar with co-processing, and few consider it a significant obstacle. Coupled with the numerous benefits of co-processing for both producers and off-takers, this is becoming an increasingly attractive option for renewable fuel production. Regulations on co-processing As mentioned in the introduction, regulatory initiatives supporting the supply or demand of SAF are being imple- mented globally. This section outlines the key regulatory initiatives introduced across various regions, as well as the regulatory fuel compliance standards for co-processing. In the EU, the ReFuelEU initiative targets a 70% SAF share by 2050, split evenly between biogenic jet fuel and eSAF. Non-compliance penalties enforce this obligation on fuel suppliers. The UK is developing a similar SAF regula- tory framework, potentially including a revenue certainty scheme. In the US, the SAF Grand Challenge promotes SAF production, bolstered by incentives like RIN credits from the Renewable Fuel Standard (RFS), LCFS credits from California, Federal production tax credits (IRA), and addi - tional credits from specific states. British Columbia, Canada, has also issued SAF mandates, targeting 1% SAF by 2028 and 3% by 2030. Other countries are also embarking on the SAF journey. Japan aims for 10% SAF by 2030, India targets 1% SAF by 2027 initially for international flights, Brazil seeks a 1%

PTQ Q2 2024