Recently FOBAS tested a number of samples from Chennai, India that exceeded the 60 mg/kg limit for Aluminium + Silicon as stipulated in the ISO 8217:2017 specification. The fuels tested had values of these catfines ranging between 79 to 110 mg/kg.
Al+Si content at these concentrations may not readily reduce to acceptable levels (< 15 mg/kg at the engine inlet) by means of normal onboard treatment. Carry over of abrasive Al+Si material may lead to damage to fuel pumps/injectors and cylinder components.
Reduction of this abrasive material to satisfactorily low levels will largely depend on the capability, effectiveness and management of the on-board fuel treatment plant. Careful monitoring and operation of fuel treatment plant is needed to reduce the risk of carryover of these abrasive elements to engine rail which can cause increase in wear of fuel pumps/injectors and cylinder components. This may include operating two separators inline under optimum conditions of flow and temperature.
If your ships are planning to bunker in this port then we suggest that the supplier is asked to provide a certificate of quality of the particular stem to ensure that the Aluminium + Silicon concentration is known at the time of bunkering and within the limits of stipulated grade. Particular attention should be given to the collection of a fully representative drip samples ensuring all supporting documentation and samples drawn are witnessed and signed for by all parties present.
Furthermore, it is recommended that during on-board treatment, system samples should be drawn and analysed in order to verify system performance is as required.