Manual of Petroleum Measurement Standards Chapter 10.4

Determination of Water and/or Sediment in Crude Oil by the Centrifuge Method

(Field Procedure)

FOURTH EDITION, OCTOBER 2013 ERRATA, MARCH, 2015

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms and Definitions 2

4. Significance and Use 2

5. Test Solvents 3

   1. General 3

   2. Use of Solvents 3

6. Demulsifier 3

7. Apparatus 4

   1. Centrifuge 4

   2. Centrifuge Tubes 5

   3. Preheater 5

   4. Sample Thermometer 5

8. Sampling 5

9. Procedure—Determination of Water and Sediment 5

   1. General 5

   2. Procedure 8

10. Calculation and Reporting—Water and Sediment 9

    1. General 9

    2. 100-mL Tubes 9

    3. 200-part Tubes 9

11. Procedure—Determination of Sediment Only 10

    1. General 10

    2. Procedure 10

12. Calculation and Reporting—Sediment Only 11

    1. General 11

    2. 100-mL Tubes 11

    3. 200-part Tubes 11

13. Precision 11

14. Bias 11

Annex A (informative) Precautionary Information 12

Annex B (informative) Demulsifiers and Water Saturation of Solvents 15

Annex C (normative) Specifications for Centrifuge Tubes 16

Annex D (informative) Procedure Outline—Determination of Water and Sediment 21

Annex E (informative) Procedure Outline—Determination of Sediment Only 22

Bibliography 23

Contents

Figures

Page

1. Reading a 100-mL Centrifuge Tube 6

2. Reading a 200-Part Centrifuge Tube 7

1. 8-in. (203-mm) Cone-Shaped Centrifuge Tube 17

2. 6-in. (167-mm) Cone-Shaped Centrifuge Tube 19

Tables

1. Rotation Speeds Necessary to Produce a Relative Centrifugal Force of 500 g for Centrifuges

   of Various Diameters of Swing. 4

2. Procedure for Reading a 100-mL Cone-Shaped Tube 6

3. Procedure for Reading a 200-Part Cone-Shaped Tube 7

4. Expression of Results for 100-mL Tubes and 200-Part Tubes 9

1. Minimum Graduation Requirements and Maximum Calibration Tolerances for 8-in. (203-mm)

   Cone-Shaped Tubes 18

2. Minimum Graduation Requirements and Maximum Calibration Tolerances for 6-in. (167-mm)

Cone-Shaped Tubes 20

Determination of Water and/or Sediment in Crude Oil by the Centrifuge Method (Field Procedure)

1. Scope

   1. This section describes the field centrifuge method for determining both water and sediment or sediment only in crude oil. This method may not always produce the most accurate results, but it is considered the most practical method for field determination of water and sediment. This method may also be used for field determination of sediment. When a higher degree of accuracy is required, the laboratory procedure described in API MPMS Ch. 10.3, Standard Test Method for Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure) (ASTM D4007); API MPMS Ch. 10.2, Standard Test Method for Water in Crude Oil by Distillation (ASTM D4006); or API MPMS Ch. 10.9, Standard Test Method for Water in Crude Oils by Coulometric Karl Fischer Titration (ASTM D4928); and the procedure described in API MPMS Ch. 10.1, Standard Test Method for Sediment in Crude Oils and Fuel Oils by the Extraction Method (ASTM D473) or API MPMS Ch. 10.8, Standard Test Method for Sediment in Crude Oil by Membrane Filtration (ASTM D4807) should be used.

      
      

   2. The requirements of this standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. The user of this standard has the responsibility for establishing appropriate safety and health practices and determining the applicability of regulatory limitations prior to use.

      
      

2. Normative References

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

API MPMS Chapter 8.1, Manual Sampling of Petroleum and Petroleum Products

API MPMS Chapter 8.2, Automatic Sampling of Petroleum and Petroleum Products

API MPMS Chapter 8.3, Standard Practice for Mixing and Handling of Liquid Samples of Petroleum and Petroleum Products (includes Errata 1 dated March 1996)

API MPMS Chapter 10.1, Standard Test Method for Sediment in Crude Oils and Fuel Oils by the Extraction Method

API MPMS Chapter 10.2, Standard Test Method for Water in Crude Oil by Distillation

API MPMS Chapter 10.3, Standard Test Method for Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure)

API MPMS Chapter 10.8, Standard Test Method for Sediment in Crude Oil by Membrane Filtration

API MPMS Chapter 10.9, Standard Test Method for Water in Crude Oils by Coulometric Karl Fischer Titration ASTM D473 1, Standard Test Method for Sediment in Crude Oils and Fuel Oils by the Extraction Method ASTM D3699, Standard Specification for Kerosine

ASTM D4006, Standard Test Method for Water in Crude Oil by Distillation

1 ASTM International, 100 Barr Harbor Drive, West Conshohocken, Pennsylvania 19428, www.astm.org.

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