Warning on Cashew Nutshell Liquid Biofuel: Risks for Marine Fuel Users
Fuel suppliers and shipping companies are exploring various non-FAME biofuels. However, CTI-Maritec, a testing firm based in Singapore, warns against using Cashew Nutshell Liquid (CNSL) biofuel. Their tests on ships fueling in Singapore and Rotterdam showed high levels of harmful compounds in CNSL blends.
Many ships reported operational issues like fuel sludging, injector failure, and clogged filters after using these fuels. CTI-Maritec analyzed samples from these vessels using Gas Chromatography Mass Spectrometry (GC-MS). They found significant amounts of compounds that indicated the fuel contained CNSL from unverified sources.
In a report dated November 21, CTI-Maritec advised shipowners against using 100 percent CNSL as marine fuel. They stated that this recommendation contradicts the International Maritime Organization’s (IMO) guidance on fuel quality. The IMO recognizes FAME-based biofuels and Hydrotreated Vegetable Oil (HVO) as acceptable, but does not approve CNSL.
What are the environmental impacts of using Cashew Nutshell Liquid (CNSL) as a marine fuel?
Interview with Dr. Linda Zhao, Biofuel Specialist at CTI-Maritec
Q: Dr. Zhao, can you explain the primary concerns associated with using Cashew Nutshell Liquid (CNSL) as a marine fuel?
A: Certainly. Our recent investigations into CNSL biofuel have revealed significant operational challenges. The tests conducted on vessels in Singapore and Rotterdam indicated high levels of harmful compounds when CNSL was blended with marine fuels. These compounds, which we detected using Gas Chromatography Mass Spectrometry (GC-MS), are particularly concerning because they point to CNSL sourced from unverified and potentially contaminated origins.
Q: What kind of operational issues have ships experienced after using CNSL blends?
A: Ships reported a range of serious operational issues, including fuel sludging that can clog filters, injector failures, and overall poor performance. These problems can lead to costly downtime and repairs, impacting shipping schedules and profitability.
Q: How does CNSL contradict the guidance provided by the International Maritime Organization (IMO)?
A: The IMO has established clear standards for acceptable marine fuels, recognizing FAME-based biofuels and Hydrotreated Vegetable Oil (HVO) as effective and safe options. However, our findings suggest that using 100 percent CNSL can lead to detrimental effects on marine engines and fuel systems, which goes against the IMO’s focus on maintaining high fuel quality. This misalignment is a serious concern for shipowners who are striving to adhere to IMO recommendations.
Q: What makes CNSL a popular choice among suppliers despite these risks?
A: CNSL is often considered an appealing option due to its low cost and renewable nature as a byproduct of the cashew nut industry. However, its high iodine value presents significant stability issues that can lead to corrosion and other damage in engines, primarily due to the fuel’s high acid content. This presents a false economy for many shipping companies, as short-term savings can quickly translate into long-term costly repairs.
Q: What recommendations do you have for shipowners regarding CNSL and other untested biofuels?
A: Our firm strongly advises shipowners to avoid using untested biofuels and blend compounds such as CNSL. We recommend conducting thorough tests on any new fuels prior to use to ensure they meet quality and compatibility standards. Understanding the properties and interactions of these fuels is crucial in maintaining engine performance and compliance with regulations.
Q: what can the maritime industry do to ensure fuel quality and protect their operations?
A: The maritime industry should prioritize fuel quality by adhering to established guidelines set by organizations like the IMO. Investing in testing and verification of fuel sources will play a vital role in avoiding the pitfalls associated with unproven biofuels like CNSL. A proactive approach will not only safeguard ship operations but also enhance sustainability efforts in the shipping sector.
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This interview seeks to provide valuable insights from Dr. Linda Zhao, shedding light on the critical issues surrounding CNSL biofuel usage in the maritime industry.
CNSL is a byproduct of the cashew nut industry. It is a low-cost renewable fuel but has stability issues due to its high iodine value. This fuel can cause corrosion in engines because of its high acid content. The potassium in CNSL blends can lead to deposits that damage turbocharger nozzle rings.
CTI-Maritec concludes that ships should avoid using untested biofuels and blend compounds. They recommend conducting thorough tests on such fuels to understand their properties and interactions with other components better.