API MPMS 10.3 2013 pdf download.Manual of Petroleum Measurement Standards Chapter 10.3 Standard Test Method for Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure).
1. Scope* 1.1 This test method describes the laboratory determination of water and sediment in crude oils by means of the centrifuge procedure. This centrifuge method for determining water and sediment in crude oils is not entirely satisfactory. The amount of water detected is almost always lower than the actual water content. When a highly accurate value is required, the revised procedures for water by distillation, Test Method D4006 (API MPMS Chapter 10.2) (Note 1), and sediment by extraction, Test Method D473 (API MPMS Chapter 10.1), shall be used. N OTE 1—Test Method D4006 (API MPMS Chapter 10.2) has been determined to be the preferred and most accurate method for the determination of water. 1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety and health practices and determine the applica- bility of regulatory limitations prior to use. Specific warning statements appear in 6.1, 8.3, and A1.5.4. 2. Referenced Documents 2.1 ASTM Standards: 2 D95 Test Method for Water in Petroleum Products and Bituminous Materials by Distillation (API MPMS Chapter 10.5)
D473 Test Method for Sediment in Crude Oils and Fuel Oils by the Extraction Method (API MPMS Chapter 10.1) D665 Test Method for Rust-Preventing Characteristics of Inhibited Mineral Oil in the Presence of Water D1796 Test Method for Water and Sediment in Fuel Oils by the Centrifuge Method (Laboratory Procedure) (API MPMS Chapter 10.6) D4006 Test Method for Water in Crude Oil by Distillation (API MPMS Chapter 10.2) D4057 Practice for Manual Sampling of Petroleum and Petroleum Products (API MPMS Chapter 8.1) D4177 Practice for Automatic Sampling of Petroleum and Petroleum Products (API MPMS Chapter 8.2) D4928 Test Method for Water in Crude Oils by Coulometric Karl Fischer Titration (API MPMS Chapter 10.9) D5854 Practice for Mixing and Handling of Liquid Samples of Petroleum and Petroleum Products (API MPMS Chap- ter 8.3) E969 Specification for Glass Volumetric (Transfer) Pipets 2.2 API Standards: 3 MPMS Chapter 8.1 Manual Sampling of Petroleum and Petroleum Products (ASTM Practice D4057) MPMS Chapter 8.2 Automatic Sampling of Petroleum and Petroleum Products (ASTM Practice D4177) MPMS Chapter 8.3 Mixing and Handling of Liquid Samples of Petroleum and Petroleum Products (ASTM Practice D5854) MPMS Chapter 10.1 Determination of Sediment in Crude Oils and Fuel Oils by the Extraction Method (ASTM Test Method D473) MPMS Chapter 10.2 Determination ofWater in Crude Oil by Distillation (ASTM Test Method D4006)
3. Summary of Test Method 3.1 Equal volumes of crude oil and water-saturated toluene are placed into a cone-shaped centrifuge tube. After centrifugation, the volume of the higher density water and sediment layer at the bottom of the tube is read. 4. Significance and Use 4.1 The water and sediment content of crude oil is signifi- cant because it can cause corrosion ofequipment and problems in processing. Adetermination ofwater and sediment content is required to measure accurately net volumes of actual oil in sales, taxation, exchanges, and custody transfers. It is not anticipated that this test method, which is written with a dedicated laboratory facility in mind, is likely to be used in field test rooms or sample rooms due to safety concerns for proper ventilation and handling. 4.2 This test method may not be suitable for crude oils that contain alcohols that are soluble in water. In cases where the impact on the results may be significant, the user is advised to consider using another test method, such as Test Method D4928 (API MPMS Chapter 10.9). 5. Apparatus 5.1 Centrifuge: 5.1.1 A centrifuge capable of spinning two or more filled cone-shaped, 203-mm (8-in.) centrifuge tubes at a speed that can be controlled to give a relative centrifugal force (rcf) of a minimum of600 at the tip ofthe tubes shall be used (see 5.1.6). 5.1.2 The revolving head, trunnion rings, and trunnion cups, including the cushions, shall be soundly constructed to with- stand the maximum centrifugal force capable of being deliv- ered by the power source. The trunnion cups and cushions shall firmly support the tubes when the centrifuge is in motion. The centrifuge shall be enclosed by a metal shield or case strong enough to eliminate danger if any breakage occurs.