SEDIMENT TESTS WATER AND SEDIMENT IN CRUDE OIL: ASTM D96
EXPLANATION
A determination of sediment and water content is required to determine accurately the net volume of crude oil involved in sales, taxation, exchanges, inventories, and custody transfers. An excessive amount of sediment and water in crude oil is significant because it can cause corrosion of equipment and problems in processing and transporting and may violate federal, state, or municipal regulations. This test method may not always provide the most accurate results, but it is considered the most practical method for field determination of sediment and water. For a higher degree of accuracy, Test Methods ASTM D4006, ASTM D4377, or ASTM D473 should be used.
TEST SUMMARY
Known volumes of crude oil and solvent are placed in a centrifuge tube and heated to 60° C. After centrifugation, the volume of the sediment-and-water layer at the bottom of the tube is read. For some waxy crude oils, temperatures of 71° C or higher may be required to completely melt the wax crystals so that they are not measured as sediment.
TEST PRECISION
The precision or bias of this test method has not yet been determined.
