Fuel viscosity tracked an upwards curve in 2023 across very low sulphur fuel oil (VLSFO) and DMA 0.1% grades, according to new statistics published by Bureau Veritas VeriFuel.
For high sulphur fuel oil (HSFO), average viscosity in Q4 2023 was 312 cSt, density was 979.3 and the percentage of off-spec fuels in relation to ISO 8217 parameters was 1.8%.
The primary causes of off-spec HSFO in Q4 were viscosity and water content.
An increase in catfines (≥ 30 mg/kg) was notable in Zhoushan across the last three quarters of 2023, rising from 0% in Q2, to 22% in Q3, and 69% in Q4. Conversely, in Gothenburg catfines fell from 73% in Q2 to 47% in Q3 and 0% in Q4.
In terms of off-spec fuels on a port-by-port basis, Piraeus ‘scored highly’ in Q4 with 11% of fuels being out of specification.
Average viscosity was also on the rise for the DMA 0.1% grade, finishing the last quarter of 2023 at 3.96 cSt, which is the highest since Q1 2022.
The main causes of off-spec DMA in Q4 were water content and appearance (not clear and bright).
Average viscosity was notably high in the ARA region last year, sitting at over 5 cSt for each of the quarters and reaching 5.36 in Q4, the highest of the year in this market and also the highest of all the ports reviewed by VeriFuel for its quarterly snapshot.
Turning to VLSFO, global average viscosity has been on the march, rising from 115 cSt in Q1 2021 to reach 167 cSt in Q4 2023. There was a notable sharp rise in viscosity in Piraeus last year, rising from 95 cSt in Q1 2023 to 229 cSt in Q4.
The global average density of VLSFO has shown an overall increase since Q1 2021, although on a much flatter trajectory than viscosity. From 938.9 in Q1 2021, density ended Q4 2023 at 947.1.
