Manual of Petroleum Measurement Standards Chapter 10.4

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

FIFTH EDITION, AUGUST 2020

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Foreword

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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 3

   1. Centrifuge 3

   2. Centrifuge Tubes 4

   3. Preheater 5

   4. Sample Thermometer 5

8. Sampling 5

9. Procedure 5

   1. General 5

   2. Determination of Sediment and Water 8

   3. Determination of Sediment Only 11

10. Calculation and Reporting of Results 13

    1. General 13

    2. 100 mL Tubes 13

    3. 200-part Tubes 13

11. Precision 14

12. Bias 14

Annex A (informative) Precautionary Information 15

Annex B (informative) Demulsifiers and Water Saturation of Solvents 18

Annex C (normative) Specifications for Centrifuge Tubes 19

Annex D (informative) Abbreviated Procedure & Calculations—Determination of Sediment & Water 23

Annex E (informative) Abbreviated Procedure & Calculations—Determination of Sediment Only 24

Bibliography 25

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Contents

Figures

Page

1. Reading a 100 mL Centrifuge Tube 7

2. Reading a 200-part Centrifuge Tube 8

1. 8 in. (203 mm) Cone-shaped Centrifuge Tube 20

2. 6 in. (167 mm) Cone-shaped Centrifuge Tube 21

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 7

3. Procedure for Reading a 200-part Cone-shaped Tube 8

4. Allowable Difference between Results from Two 100 mL Tubes 11

5. Allowable Difference between Results from Two 200-part Tubes 11

6. Calculation and Reporting of Test Results 13

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

   Cone-shaped Tubes 21

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

Cone-shaped Tubes 22

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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 sediment and water 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 sediment and water. 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 Chapter 10.2, Standard Test Method for Water in Crude Oil by Distillation (ASTM D4006); or API MPMS Chapter 10.9, Standard Test Method for Water in Crude Oils by Coulometric Karl Fischer Titration (ASTM D4928); and the procedure described in API MPMS Chapter 10.1, Standard Test Method for Sediment in Crude Oils and Fuel Oils by the Extraction Method (ASTM D473) or API MPMS Chapter 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 documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any addenda) 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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