Improvement in Diesel Fuel Quality in Thailand 2009-01-1851

Diesel fuel is a major grade in the Thai market used in transportation of goods and in most light duty vehicles. Over the last fifteen years the quality of this fuel has continuously increased. This is one of the major factors that have allowed a substantial improvement in air quality.

The improvement in diesel fuel quality has been achieved by using a mix of measures, some well known like reduction in sulphur content, whilst others are unique to this market.

Since 1993, in Thailand it has been mandatory to use a diesel detergent. This has ensured best driveability and lowest emissions due to the control of injector deposits. This measure was unique in the world and although not mandatory any longer, this market has a large proportion of automotive diesel treated with this type of additive. Another action has been the evaluation of Palm Oil Methyl Ester (PME) and its potential impact in the market. However, experience with PME is limited. Therefore, a complex evaluation program was undertaken to confirm the suitability of this grade. The testing ranged from field testing to bench engine testing using current and advanced Fuel Injection Equipment (FIE). The field testing was run for 100,000 km with eight common-rail light duty cars using B0 and B5 (PME) fuel containing a diesel detergent.

PME at the level tested showed no harms for emissions and for any engine part that were fully inspected at the end of the mileage accumulation test.

All these activities have been tailored to match the local market requirements. A measure of their success is the fact that the introduction of PME containing diesel has been done without any field complaint.