Manual of Petroleum Measurement Standards Chapter 10.3

Standard Test Method for Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure)

FOURTH EDITION, AUGUST 2013

REAFFIRMED, MAY 2016

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Foreword

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Contents

1. Scope 1

2. Referenced Documents 1

3. Summary of Test Method 2

4. Significance and Use 2

5. Apparatus 2

6. Solvent 3

7. Sampling 3

8. Procedure 3

9. Calculation 5

10. Precision and Bias 5

11. Keywords 6

Annex A1 (Mandatory Information) Procedure to Water-saturate Toluene 6

Appendix X1 (Nonmandatory Information) Precision and Accuracy of Methods for Determining

Water in Crude Oils 7

Figures

1. Eight-Inch (203 mm) Centrifuge Tube 3

2. Procedure for Reading Water and Sediment When Using an ASTM 100-mm

   Cone-Shaped Centrifuge Tube 4

3. Basic Sediment and Water Precision 5

A1.1 Solubility of Water in Toluene 6

X1.1 Basic Sediment and Water Precision for ASTM Test Method D95 (API MPMS Chapter 10.5)

Distillation (Based on Seven Laboratories) 11

X1.2 Basic Sediment and Water Precision for ASTM Test Method D1796 (API MPMS Chapter 10.6)

Centrifuge (Based on Five Laboratories) 11

X1.3 Basic Sediment and Water Precision for ASTM Test Method D1796 (API MPMS Chapter 10.6)

Centrifuge (Based on Six Laboratories) 12

Tables

1. Centrifuge Tube Calibration Tolerances for 203 mm (8 in.) Tube 3

2. Expression of Results, mL 5

X1.2 Base Case—Water Content of Crudes 8

X1.3 Water Content of Crude Oil Samples 8

X1.5 Determination of Water in Crude Oils, % H2O 8

X1.6 Corrections to be Applied to Measured Values to Obtain “True’’ Water Content 9

X1.7 Bias of Methods Estimated from Spiked Samples 9

X1.8 Round-Robin Results of Water in Crude Oils by ASTM D95 (API MPMS Chapter 10.5)

and ASTM D1796 (API MPMS Chapter 10.6) 10

X1.11 Constants (see Eq X1.1) 10

X1.12 ASTM Precision Intervals: ASTM D95 (API MPMS Chapter 10.5) (7 Laboratories) 11

X1.13 Limiting Repeatabilities and Reproducibilities 12

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Designation: D4007 − 11 (Reapproved 2016)´1

Manual of Petroleum Measurement Standards (MPMS), Chapter 10.3

Standard Test Method for

Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure)1

This standard is issued under the fixed designation D4007; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.

ε1 NOTE—Subsection X1.3.3.2 was revised editorially in November 2016.

1. Scope

   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.

      NOTE 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.

   2. The values stated in SI units are to be regarded as standard.

      1.2.1 Exception—The values given in parentheses are for information only.

   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.

      
      

      1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and the API Committee on Petroleum Measurement and is the direct responsibility of Subcommittee D02.02

      /COMQ the joint ASTM-API Committee on Hydrocarbon Measurement for Custody Transfer (Joint ASTM-API). This test method has been approved by the sponsoring committees and accepted by the Cooperating Societies in accordance with established procedures.

      Current edition approved June 1, 2016. Published July 2016. Originally approved in 1981. Last previous edition approved in 2011 as D4007 – 11ɛ1. DOI: 10.1520/ D4007-16E01.

      
      

2. Referenced Documents

   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. 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)

2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website.

3 Available from American Petroleum Institute (API), 1220 L. St., NW, Washington, DC 20005-4070, www.api.org.

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