Lubricity
Dosages pushing against the maximum limit for multi-product pipelines.
A refinery using the mono-acid chemistry to achieve the HFRR wear scar specification.
Cemeg Support
The refinery was observed to be using 250 plus ppm when other plants on apparently similar blends were running below 200ppm. Comparison of a number of split samples run on the refinery and other plants HFRR instruments indicated a small but significant delta with the refinery measuring higher on average. Round robin studies had all been considered acceptable and for the samples circulated, near to the average.
However, studying a number of samples, the statistics highlighted the dosage impact of being in mid-quartile 2 below, rather than 3 above the average. In certain blends, the response curve can be quite shallow above 200ppm and combined with the poor repeatability of the HFRR test, the higher dosages were needed to achieve acceptable first time pass rates.