Marine Fuels Analyser for Sulphur and Metals in Bunker Fuel and Marine Diesel

Regulations limiting the sulphur (S) content of fuel used in the marine industry continues to evolve. As of January 1, 2015 the revised Annex VI to Marpol 73/78 reduced the maximum sulfur content allowed when entering ECA’s (Emission Control Areas) to 0.1 wt%. After January 1, 2020 new International Maritime Organisation (IMO) regulations require the sulphur content of any fuel used on board ships not to exceed 0.5 wt%. This is a substantial reduction from the 3.5 wt% limit established January 1, 2012.

To meet the needs of the industry, Rigaku offers the NEX QC Marine Fuel Analyser, (MFA) a simple, versatile, and portable benchtop energy dispersive X-ray fluorescence (EDXRF) analyser for the analysis of sulphur in marine fuels. The Rigaku NEX QC analyser complies with international standards test methods for measuring sulphur in crude, bunker fuel, diesel and other petroleum oils. The MFA system is optimised for marine fuel analysis applications.

Specifically designed to meet IMO 2020 regulations for marine fuel sulfur content, the Rigaku NEX QC MFA features an intuitive "icon-driven" touch screen interface for ease of operation and a built-in printer for convenience. The 50 kV X-ray tube and Peltier cooled semiconductor detector coupled with multiple automated X-ray tube filters, allows for the sulphur content of marine fuels to be determined according to ASTM D4294 and ISO 8754.

In addition to sulphur, the unit can be set up to monitor the nickel (Ni), vanadium (V) and iron (Fe) content of residual oils or to ensure fuels have not been adulterated with used engine oil or other undesirable oils. Screening for zinc (Zn) will help ensure fuels are free of used engine oil.

Economical and easily transportable, the compact NEX QC MFA includes a rugged carrying case and two marine fuel Application Packages:

The Sulphur-Pak™ includes pre-installed calibrations and check standards for diesel and residual oil. 

The Marine Metal-Pak™ includes calibrations, and check standards for S, Fe, Ni and V in heavy fuel oil.

It is ideal for measuring diesel 0.05-1.0% targeting 0.1% sulphur and bunker fuels 0.1- 3.5% targeting 0.5% sulphur.

Sample Preparation

To measure a sample, gently shake the sample bottle, allow bubbles to settle and fill a 32mm XRF sample cup 3/4 full (approximately 5g)

Sulfur and Metals in Bunker Fuel

Empirical calibrations were built using a suite of 12 commercially available residual oil calibration standards (See Table 1).

To demonstrate repeatability, samples were measured in static position for ten repeat analyses using a total analysis time of 260 sec per measurement, with typical results shown in Table 2.

Conclusion

The performance shown demonstrates the ability of the NEX QC analyzer to yield excellent results for the measurement of sulfur and metals in bunker fuel and marine diesel. The system also has the capabilities to screen for elements such as Zn, Ni, and V in adulterated fuels.

Additional information about EDXRF / XRF resources for Petroleum & Petrochem applications is available here.