SEDIMENT TESTS WATER AND SEDIMENT IN MIDDLE DISTILLATE FUELS: ASTM D2709
EXPLANATION
Appreciable amounts of water and sediment in a fuel oil tend to cause fouling of the fuel handling facilities and to give trouble in the fuel system of a burner or engine. An accumulation of sediment in storage tanks and on filter screens can obstruct the flow of oil from the tank to the combustor. Water in middle distillate fuels can cause corrosion of tanks and equipment, and if detergent is present, the water can cause emulsions or a hazy appearance. Water is necessary to support microbiological growth at fuel-water interfaces in fuel systems.
This test method is used as an indication of water and sediment in middle distillate fuels having viscosities at 40° C in the range of 1.0 to 4.1 cSt and densities in the range of 770 to 900 kg/m3.
TEST SUMMARY
A sample of fuel is centrifuged at an rcf of 800 for 10 min at 21 to 32° C in a centrifuge tube readable to 0.005 mL and measurable to 0.01 mL. After centrifugation, the volume of water and sediment that has settled into the tip of the centrifuge tube is read to the nearest 0.005 mL.
TEST PRECISION
Repeatability: 0.014 volume percent
Reproducibility: 0.041 volume percent
The bias of this test method is not known.
