The problem

Equipment manufacturers (OEM's) are under pressure to reduce emissions and fuel consumption. To achieve this they have built into new diesel engines many technical innovations. The most significant of these been increased injection pressure. This has resulted in far smaller tolerances less than (1 micron) during manufacture and assembly.

Environmental pressure is also forcing refineries to produce fuels with lower sulphur levels and the great misconception that has arisen is that this diesel fuel is referred to commonly as clean diesel.

Most Governments rely on existing diesel fuel specifications in their local markets but few if any of these specifications take into account other contaminants such as particulate matter. To quote from a Technical Bulleting from Polaris Laboratories "How Clean is Your Fuel?"

Engine manufacturers are realizing that diesel fuel cleanliness can have great impact on overall engine performance. In fact many are now recommending that diesel fuel that does not meet an ISO Cleanliness Code of 18/16/13 should be filtered before introduction to the fuel system.

In the Paper by Phillip Johnson of the Donaldson Company "Fuel Filtration Reality Check" Paper No IFC09-018, he states that

Current cleanliness recommendations by some manufacturers of high pressure fuel injection systems have already indicted they need significantly cleaner fuels. They already require fuel in an ISO 4406 cleanliness range of 12/9/6 or better for on-vehicle filtration.

He further goes on to say that

While this is relatively difficult to achieve, it's not an unrealistic objective even using current filtration technology. To get to these cleanliness levels will most likely require high efficiency filtration and possibly multiple filtration cycles.

In essence the problem we face is to voluntarily meet the requirements of the OEM's thus satisfying the customer in terms of equipment reliability and performance.

So what is the Solution?

Fuel marketing companies are required to deliver fuel meeting the customer's requirements in terms of their OEM specification demands. End users need to develop the capacity to maintain this fuel in bulk storage up to the point of discharge into the equipment. Customer need to ensure that the necessary on board filtration is adequate to meet the OEM demands of the fuel injection system.

Good fuel management will also require the necessary control and testing equipment and implementation of procedures to ensure compliance to these standards.

This is probably easier said than done when one looks at the varied operating environments in and around Africa, but in my humble opinion achievable.

Andrew Kirk