NB/SH/T 0908-2015 Determination of Stability and Compatibility of Heavy Fuel Oils and Crude Oils Optical Detection Method

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Card type: Test method

1. Method number / full name / English name / replacement relationship

• Standard number: NB/SH/T 0908—2015
• Chinese name: Determination of Stability and Compatibility of Heavy Fuel Oils and Crude Oils Optical Detection Method
• English name: Standard test method for determining stabillity and compatilbility of heavy fuel oils and crude oils by heavy fuel oil stability analyzer (optical detection) (in the English name, the spellings of stabillity and compatilbility are suspected to be caused by the original text/source-text extraction, requires confirmation against the source standard (source-text extraction))
• Replacement relationship: This standard is first published (original text: This standard is first published)
• Adoption relationship: Modified adoption using the redrafting method of ASTM D7112-12 "Determination of Stability and Compatibility of Heavy Fuel Oils and Crude Oils by Heavy Fuel Oil Stability Analyzer (Optical Detection Method)"
• Main differences from ASTM D7112-12: Chapter 2 "Normative References" adopts corresponding national standards and industry standards
• Publication/implementation: published on 2015-10-27, implemented on 2016-03-01
• Issuing authority: National Energy Administration
• Secretariat: Subcommittee on Petroleum Fuels and Lubricants of the National Technical Committee for Standardization of Petroleum Products and Lubricants (SAC/TC280/SC1)
• Drafting organization: Sinopec Research Institute of Petroleum Processing
• Main drafters: Wang Xiaowei, Wang Jing

2. Scope of application and non-applicability

• Applicable: specifies an automatic titration and optical detection method for asphaltene flocculation, used to determine stability and compatibility parameters of petroleum refining residuum materials, residual fuel oils, and crude oils.
• Applicable samples: residues from atmospheric and vacuum distillation, thermal processing, catalytic and hydrocracking processes, such as samples conforming to grades F-R1, F-R2, F-R3 and F-R4 in the GB 25989—2010 product classification (the original text writes "F-RI, F-R2, F-R3 and F-R4", suspected to be source-text extraction, requires confirmation against the source standard (source-text extraction)); petroleum fuel samples containing heavy components from petroleum refining in the GB/T 29114—2012 product classification; and crude oils.
• Not applicable: samples with asphaltene mass fraction less than 0.05%; for unstable samples in which asphaltene flocculation has already occurred, no titration endpoint can be obtained.

3. Method principle

The stability and compatibility parameters are determined by optically detecting the initial asphaltene flocculation point during titration. First, prepare three stock solutions of xylene-sample in different proportions, then titrate with n-heptane to promote asphaltene precipitation. During titration, the mixed liquid continuously circulates through the optical detector, and asphaltene flocculation is judged by detecting changes in the scattering intensity of visible light. The stability parameters are calculated from the amounts of sample, xylene, and n-heptane used: xylene equivalent value SE, P value, and FRs1. If the density is known, the compatibility parameters of crude oil (SBN and IN) can also be calculated.

4. Reagents and materials (purity / preparation)

• General: Unless otherwise specified, all reagents used in the test are analytical grade reagents. If reagents of other grades are used, their purity shall not reduce the precision of the determination.
• 8.1 Xylene (C8H10, original text writes "C8I", requires confirmation against the source standard (source-text extraction)): Warning: flammable, harmful to health. Toluene is usually the ortho, meta, and para xylene isomers or a mixture, and may contain some ethylbenzene (this sentence in the original text is suspected to be erroneous, requires confirmation against the source standard (source-text extraction)).
• 8.2 n-Heptane (C7H16, original text writes "C,Hio", requires confirmation against the source standard (source-text extraction)): Warning: flammable, harmful to health.
• Stock solution preparation: see Article 14.1 (40 g sample + 20 g xylene).

5. Instruments and equipment

• 7.1 PORLA Heavy fuel oil and crude oil stability and compatibility analyzer (see Figure 1, Figure 2), main components:
  • 7.1.1 Sample cup: made of lightweight, inert material, with a flat and smooth bottom, volume about 100 mL, usually an aluminum cup is used.
  • 7.1.2 Sample turntable: a sample holder with 4 positions, continuously delivering sample cups to the measurement position.
  • 7.1.3 Stirring lifting system: a vertical lifting system combined into a sample cup lid at the measurement position, including a mechanical stirrer that starts rotating upon reaching the measurement position, liquid delivery tubes for adding n-heptane and xylene, a circulation tube that makes the sample pass through the detector, and a cleaning tube that empties the sample cell after measurement.
  • 7.1.4 Aromatic solvent pump: a precisely adjustable ceramic piston pump, capable of pumping xylene at a rate of 0.01 mL/s~0.5 mL/s.
  • 7.1.5 Normal alkane solvent pump: a precisely adjustable ceramic piston pump, capable of pumping n-heptane at a rate of 0.01 mL/s~0.5 mL/s.
  • 7.1.6 Circulation pump: a precisely adjustable ceramic piston pump, making the measurement solution circulate in the detection system.
  • 7.1.7 Drain pump: a precisely adjustable ceramic piston pump, used to empty the sample cup at the end of measurement.
  • 7.1.8 Detection system: an optical detector through which the sample continuously circulates (see Figure 3). The detector consists of a visible light source and a photodiode that records the light reflected by asphaltene particles in the sample.
  • 7.1.9 Heating plate: a temperature-controlled heating system placed under the sample cup, heating the sample so that titration can be completed above room temperature. The temperature of the heating plate can be adjusted between 20 ℃~100 ℃.
• 7.2 Computer: controls the measurement and calibration procedures, and provides an interactive interface between the operator and the analytical instrument.
• 7.3 PORLA Measurement procedure display window: displayed by the computer, allowing input of sample data and operator information, and simultaneously displaying the results of each titration (see Figure 4).
• 7.4 PORLA Measurement parameter window: displayed by the computer, allowing adjustment of the default values of all measurement cycle parameters, and also allowing pump calibration (see Figure 5).

6. Recommended operating conditions

• 14.3 The measurement is usually carried out under laboratory room temperature conditions. Samples with special properties (such as high viscosity) can be measured at a higher temperature by setting the heating plate to an appropriate temperature and recording the test temperature. Note: Relying on the heat generated by the instrument, the measurement temperature is usually slightly higher than room temperature; test results during the development of this standard show that small temperature fluctuations have no effect.
• 14.11 Parameter window settings (expected optimal values for each sample):
  • 14.11.1 Number of cleaning cycles: use at least two cycles, recommended three cycles; after analysis, perform one cycle cleaning only after each sample analysis.
  • 14.11.2 Cycle time: usually set to 60 s–10 s (original text as such, suspected to be an error for 60 s–120 s, requires confirmation against the source standard (source-text extraction)), sufficient cycle time ensures stable measurement results.
  • 14.11.3 Evacuation line time: usually set to 30 s.
  • 14.11.4 Stirring time: usually set to 60 s.
  • 14.11.5 Normal alkane pump rate: set the pump rate to 0.05 mL/s (the unit at source-text extraction is missing in the original text, requires confirmation against the source standard (source-text extraction)).
  • 14.11.6 Aromatic pump rate: set the pump rate to 0.07 g/s.
  • 14.11.7 Drain pump speed: set the speed to 0.4 g/s.
  • 14.11.8 Aromatic pumping time: set the time to 45 s.
  • 14.11.9 Cleaning time: set the cleaning time to 60 s.
  • 14.11.10 Cup capacity: although the actual capacity of the measuring cup is 100 mL, the recommended maximum cup capacity setting is 55 mL. Note: If the asphaltene content of the sample is less than 0.05%, the maximum limit of the sample cup will be reached, and the titration process will stop automatically.
  • 14.11.11 Normal alkane step size: for samples with poor stability, use small step values such as 0.3 mL–0.5 mL; usually for visbreaking products, use larger step values such as 0.5 mL–1 mL; for highly stable samples such as crude oil and atmospheric/vacuum distillation residua, use step values of 1 mL~3 mL.
  • 14.11.12 Waiting time: set 60 s–120 s (original text "60s–120", unit suspected missing, requires confirmation against the source standard (source-text extraction)).
  • 14.11.13 Pre-added normal alkane factor: the ratio value of the estimated total n-heptane consumption pre-added to the measuring cup, expressed as a decimal (e.g., 0.4 means 40%). Enter 0 when no pre-addition is desired. An initial pre-addition ratio value greater than 0.4 can be used for research purposes and should not be used in standard measurement procedures.
  • 14.11.14 Aromatic evaporation rate (g/h): for calculation see Article 12.2.
• 12.1 Pump calibration: perform pump calibration at initial installation and during use. When the instrument is used continuously, perform pump calibration once a month.
• 12.2 Evaporation correction coefficient: place a sample cup containing xylene stock solution on the measurement turntable, weigh the mass of the sample cup after 0.5 h, 1.0 h and 1.5 h (to the nearest 0.01 g), calculate the average solution evaporation loss expressed as g/h, which is the evaporation correction coefficient of xylene. When the instrument is used continuously, calibrate the evaporation correction coefficient once every quarter.

7. Sampling and sample preparation

• 10.1 Sampling: Unless otherwise specified, sampling shall be carried out in accordance with GB/T 4756 or GB/T 27867. Ensure the sample is representative.
• 10.2 Sampling amount: at least 40 g (the minimum sample quantity is unclear in the source transcription and remains unverified); if necessary, it is best to collect more sample (e.g., 200 g~300 g) to allow multiple measurements.
• 10.3 The sample should be homogeneous before sampling.
• 10.4 Samples should be exposed as little as possible to air at or above 25 ℃ and to light. Store samples in sealed, opaque containers, such as metal cans or brown glass bottles, to avoid change or deterioration.
• 14.1 Sample preparation:
  • 14.1.1 Stock solution: In a sealed glass container with a stopcock (volume approximately 100 mL), mix 40 g of sample and 20 g of xylene.
  • 14.1.2 Vigorously shake the container holding the sample for at least 2 min to mix the sample thoroughly. If the sample viscosity is very high, it may be heated in a heating furnace before shaking. Usually the heating temperature does not exceed 80 ℃.
  • 14.1.3 In a sealable container, weigh 20 g of xylene, then add 40 g of sample, accurate to 0.01 g.
  • 14.1.4 Shake the stock solution container until the sample dissolves in the xylene. Ensure the sample is completely dissolved before testing. Generally, whether the sample in the stock solution is completely dissolved in xylene can be judged visually.
  • 14.1.5 If the sample is very difficult to dissolve, a reflux apparatus may be used instead of shaking. When using a reflux apparatus, allow the stock solution to cool before pouring it into a sealed container.

8. Analysis procedure

• 11 Instrument preparation:
  • 11.1 Read the instrument operating instructions and follow all recommended procedures.
  • 11.2 Place the instrument in a level, well-ventilated location, such as inside a fume hood.
  • 11.3 Connect the analyzer and computer to a suitable AC power supply, and connect the analyzer, keyboard, monitor, and mouse cables to the computer. Note: Except for the main power switch, all controls of the instrument are operated through the computer using the mouse and keyboard.
  • 11.4 Fill the aromatic and normal paraffin solvent bottles with xylene and n-heptane respectively, and ensure the waste liquid bottle is empty. Connect the three plastic bottles labeled aromatic solvent, normal paraffin solvent, and waste liquid to the corresponding instrument lines (the liquid-line description is unclear in the source transcription; its interpretation as waste liquid remains unverified).
  • 11.5 Turn on the push-button switch at the upper right of the instrument front panel; a green indicator light will illuminate.
  • 11.6 Turn on the computer.
  • 11.7 Double-click the PORLA measurement button to open the PORLA system measurement interface (see Figure 4) or the system self-check interface.
• 14.2 Experiment information and instrument settings:
  • 14.2.1 Open the PORLA measurement interface and enter the operator name and sample name in the corresponding positions.
  • 14.2.2 Enter the amounts of sample and xylene used to prepare the stock solution in the corresponding positions, accurate to 0.01 g.
  • 14.2.3 If compatibility parameters are required, enter the 15 ℃ density of the sample (unit g/mL) in the corresponding position. If necessary, determine the density value using a method suitable for the sample type.
  • 14.2.4 Select xylene from the aromatic solvent drop-down menu.
  • 14.2.5 Before each measurement, ensure there is sufficient solvent volume in the aromatic (xylene) and normal paraffin (n-heptane) containers, and that the waste liquid container also has sufficient space to hold the waste liquid generated during the measurement. Note: If the n-heptane has been used up, or is used up during the measurement, the instrument will continue pumping air until the total pumped volume reaches the set measurement cell volume (usually set to 55 mL); at this point the instrument will stop and display that the sample cell is full.
• 14.4 Rapid measurement procedure for unknown samples (determining the maximum consumption of n-heptane):
  • 14.4.1 Weigh 15 g of stock solution into the sample cell, accurate to 0.01 g, and place the sample at position 1 on the measurement turntable.
  • 14.4.2 Enter the sample mass into the start test window, accurate to 0.01 g, and enter zero for the pre-added n-heptane milliliters.
  • 14.4.3 Click the "Start" button to begin the measurement. The analyzer will continuously add n-heptane until asphaltene flocculation occurs. Asphaltene flocculation is indicated by the light intensity bar and the light intensity value window; the light intensity bar and light intensity value will be displayed as full and 10.00 respectively.
  • 14.4.4 Read the amount of n-heptane consumed from the milliliters of normal paraffin directly below the light intensity.
• 14.5 After performing the rapid measurement procedure or a pre-test, divide the total amount of n-heptane consumed by 20 to obtain a roughly reasonable step size value for the main measurement process. Enter this calculated step size value into the corresponding window in the parameter window.
• 14.6 Based on 14.4.4 or previous experience, enter the total estimated n-heptane consumption of the test sample into the normal paraffin milliliters position to the right of the test start position.
• 14.7 Select the titration method from the drop-down menu to the right of the start button:
  • 14.7.1 For highly stable samples such as crude oil, straight-run residuum, visbroken and low-severity hydrocracked residuum, select the commonly used low flocculation ratio.
  • 14.7.2 For low-stability samples such as high-severity cracked residuum, select the high flocculation ratio. Typical low-stability samples usually have FRs1 higher than 0.7.
  • Note 1: For the low flocculation ratio, the PORLA instrument selects xylene-to-oil dilution ratios of 1:2, 1:1, and 2:1. For the high flocculation ratio, the PORLA instrument selects xylene-to-oil dilution ratios of 2:1, 3:1, and 4:1.
  • Note 2: The third mode allows the operator to edit the method and select the dilution ratio. Using this mode is useful for research, but will deviate from the standard method.
• 14.8 Select the titration method to determine the xylene dilution rate used for the analyzer and the mass of stock solution placed in each sample cell.
• 14.9 The analyzer can operate in fully automatic and semi-automatic modes. The mode can be selected from the drop-down menu above the method menu (see Figure 4). Routine operation (Normal Operation) is fully automatic mode; light samples (Light Ends) are semi-automatic mode. Light sample mode is only used when the sample contains a large amount of volatile components; if several sample cells are placed on the measurement turntable waiting for a long time, these volatile components will decrease due to volatilization. In light sample (semi-automatic) mode, place one sample cell on the turntable at a time. When the instrument stops after each titration, place the next sample cell.
• 14.10 According to the mass indicated by the test dialog box in the software (accurate to 0.01 g), weigh the stock solution into 3 sample cells, and place the sample cells on the sample turntable. Modify the numbers on these dialog boxes so that they match the actual weighed sample amounts, and enter the turntable positions in the dialog boxes to the right of these mass data.
• 14.12 Click the "Start" button to begin the analysis.
• 14.13 After the analysis starts, an "Interrupt" button appears next to the "Start" button. If necessary, this allows the analysis to be interrupted immediately.
• 14.14 The instrument will complete three titrations and provide the measurement results in numerical and graphical form in the lower part of the measurement window (see Figure 4 and Figure 6).
• 14.15 The solvent ratio and oil sample-to-solvent ratio obtained from the crude oil compatibility measurement will be given in the corresponding dialog boxes of FR and 1/X.
• 14.16 A straight line is obtained by least squares fitting; the intercept of the resulting line on the y axis is given in the dialog box of FRmax. The extrapolated value of the amount of n-heptane consumed by the diluted sample is given in the Xmin dialog box. The slope of the resulting curve is given in the slope dialog box. The peptizing ability or P value of the asphaltene is given in the Pa dialog box. The peptizing ability of the oil matrix is given in the Po dialog box. The correlation coefficient indicating the significance level of the linear fit is given in the r² dialog box. The crude oil compatibility parameter P value and the 5 mL solvent ratio 1 g sample flocculation ratio are given in the P value and FRs1 dialog boxes respectively.
• 14.17 If the crude oil compatibility software is installed and the density of the measured crude oil has been entered into the D (g/mL) dialog box before measurement, the insolubility parameter (IN) and solubility parameter (SBN) of the mixing model will be given in the IN and SBN dialog boxes respectively.

9. Qualitative and quantitative and calculation formulas

• 15.1.1 Calculate the flocculation ratio (FR), volume fraction (%): FR = Varom / (Varom + Vpara) × 100 …… (1) Where: Varom—— volume of aromatic hydrocarbons in the mixed solution, mL; Vpara—— volume of normal paraffin, mL.
• 15.1.2 Calculate the aromatic solvent equivalent value (SE), volume fraction (%): SE% = (FRs1) × 100 …… (2) Where: FRs1——5 mL the flocculation ratio when a solution composed of xylene and n-heptane is diluted and mixed with 1 g oil sample.
• 15.1.3 Calculate the sample-to-solvent ratio (1/X), unit g/mL: 1/X = Moi / (Varom + Vpara) …… (3) Where: Moi—— mass of sample, g.
• 15.1.4 Calculate the P value of the sample, unit mL/g: P = 1 + Xmin …… (4) Where: Xmin—— at FR=0, 1 g the n-heptane consumed when flocculation occurs in the sample not diluted with xylene, mL/g.
• 15.1.5 Calculate the peptizing property of asphaltene Pa: Pa = 1 - FRmax …… (5) Where: FRmax—— maximum flocculation ratio (at 1/X=0).
• 15.1.6 Calculate the peptizing ability of the sample matrix Po: Po = FRmax × P or Po = (FRmax) × (1 + Xmin) …… (6)
• 15.2 Crude oil sample compatibility parameter: IN = SE / (1 - V1/25D) …… (7) (the original formula source-text extraction is suspected to be erroneous; requires confirmation against the source standard (source-text extraction)) SBN = 1 × (1 + V1/5) ……(8) (the original formula source-text extraction is suspected to be erroneous, requires confirmation against the source standard (source-text extraction)) Where: D—— density of the crude oil sample, g/mL; V1—— volume of n-alkane that can be added to 5 mL sample without asphaltene flocculation, mL.
• Terms and definitions (Chapter 3):
  • 3.1.1 Asphaltenes: petroleum components that can dissolve in a specific aromatic solvent but will separate and precipitate when an excess of a specific n-alkane solvent is added. Note: In this standard, the aromatic solvent is xylene, and the n-alkane solvent is n-heptane.
  • 3.1.2 Compatibility: the phenomenon in which two or more crude oils or fuel oils, after being mixed in a certain proportion, do not exhibit asphaltene flocculation or phase separation.
  • 3.1.3 Flocculation (flocculation): the original text source-text extraction is severely damaged, requires confirmation against the source standard (source-text extraction).
  • 3.1.4 Storage stability: the property of heavy fuel oils and residual oils containing asphaltenes that keeps asphaltenes in a peptized (colloidally dispersed) state without flocculation during storage or when mixed with other oils. Note: Oils with high stability can be stored for a longer time or can be mixed with other oils over a wider proportion range without asphaltene flocculation.
  • 3.1.5 Aromatic solvent equivalent value (SE): when a solvent containing an aromatic and an n-alkane (xylene and n-heptane) is mixed with a sample without asphaltene flocculation, the minimum content of the aromatic (xylene) in the solvent, expressed as volume fraction, %. Note: it is FRs1 multiplied by 100%, see formula (2).
  • 3.1.6 Evaporation correction factor: the volatilization rate of xylene in the sample cup, in grams per hour (g/h).
  • 3.1.7 Flocculation ratio (FR): when mixed with a sample, the lowest concentration of aromatic solvent at which asphaltene flocculation does not occur, expressed as the ratio of xylene to the aromatic and n-alkane solution (xylene + n-heptane). See formula (1).
  • 3.1.8 FRs1: the flocculation ratio when a solution composed of xylene and n-heptane is diluted and mixed with 1 g oil sample (see 3.1.7). This ratio is widely used by some petroleum companies engaged in research on the stability and compatibility of crude oils and heavy fuel oils. The value of P is equal to FRs1 is equal to 0 (this sentence in the original text source-text extraction is damaged, requires confirmation against the source standard (source-text extraction)).
  • 3.1.9 Insolubility parameter (IN): one of the mixing model parameters used to determine the compatibility of crude oils after mixing. Note: it is calculated from the density of the crude oil, the aromatic solvent equivalent value, and the maximum volume allowed when n-heptane is added to 5 mL sample without asphaltene flocculation. See 15.2 for the formula.
  • 3.1.10 Maximum flocculation ratio (FRmax): the minimum peptizing ability required to disperse asphaltenes in the colloidal dispersion system of crude oil and heavy fuel oil, expressed as the volume ratio of aromatic solvent (xylene) to aromatic solvent plus n-alkane solvent (n-heptane). By plotting the concentration and extrapolating outward to the intersection with the y axis when the sample is infinitely diluted, FRmax can be calculated.
  • 3.1.11 P value: a parameter used to characterize the stability or peptizing ability of refinery crude oils, heavy fuel oils, and residual oils with respect to asphaltene precipitation. Note: the expression for the P value is P=1+Xmin, where Xmin is the minimum milliliters of n-heptane consumed when n-alkane (n-heptane) is added to 1 g oil until asphaltene flocculation occurs. The minimum value of P is 1, that is, an unstable oil has already undergone asphaltene precipitation without adding any n-alkane solvent. The higher the P value, the more stable the asphaltenes in the oil.
  • 3.1.12 Oil matrix: the part of crude oil and heavy fuel oil that surrounds the asphaltenes and forms a colloidal dispersion system. Note: For the purpose of determination, the sample is divided into oil matrix (sometimes also called oil medium) and asphaltenes.
  • 3.1.13 P value of asphaltenes: the ability of asphaltenes to remain peptized.
  • 3.1.14 P value of the oil matrix: the peptizing ability of the oil matrix.
  • 3.1.15 Peptization (pepuze, suspected to be peptize, requires confirmation against the source standard (source-text extraction)): dissolving asphaltenes or keeping asphaltenes in a colloidally dispersed state.
  • 3.1.16 Mixing solubility parameter (SBN): the second of the mixing model parameters for determining the compatibility of crude oils after mixing. It is determined and calculated from the density of the crude oil, the aromatic solvent equivalent value, and the maximum volume of n-heptane added to 5 mL sample without asphaltene precipitation. See 15.2 for the formula.
  • 3.1.17 Step size (step size): the sample solution in a certain amount of xylene added at one time to the standby solution (stock solution) during the determination process (this item in the original text source-text extraction is damaged, requires confirmation against the source standard (source-text extraction)).
• 3.2 Symbols: FR—— flocculation ratio; FRs1——5 mL flocculation ratio when the aromatic + n-alkane solution (xylene and n-heptane) is diluted and mixed with 1 g oil sample; FRmax—— maximum flocculation ratio; IN—— insolubility parameter; P—— P value of the oil sample; Pa—— P value of asphaltenes; Po—— P value of the oil matrix or peptizing ability; SBN—— mixing solubility parameter; SE—— aromatic solvent equivalent; Xmin—— amount of n-heptane consumed by the diluted oil, expressed as mL/g.

10. Precision

• 17.1 Precision: judge the reliability of test results according to the following provisions (95% confidence level).
  • Note 1: The precision of P, Pa, Po and FRs1 was obtained from the determination results of 11 samples (heavy fuel oil, atmospheric and visbreaking residual oils, and crude oil) by multiple laboratories; the mass fraction range of asphaltenes in these samples determined by method SH/T 0266 is 0.7%~22.5%. The repeatability precision was obtained at the same location by five operators using three instruments.
  • Note 2: The precision of this test method may not be applicable to samples outside this research report.
• 17.1.1 Repeatability: in the same laboratory, by the same operator using the same instrument, according to the same method, the difference between two consecutive test results obtained on the same sample shall not exceed the requirements of Table 1.

Table 1 Repeatability requirements

Note 1: X—— the average of two determination results. Note 2: Method for determining the recommended precision range: (minimum sample average - repeatability) to (maximum sample average + repeatability).

• 17.1.2 Reproducibility: the reproducibility of the method was not investigated because it is irrelevant to the application of this method. This method determines some unstable special samples; the results for these samples will be inconsistent when placed in different laboratories, under different exposure environments, and for different times.
• 17.2 Bias: because the determination results of this standard are defined only in this standard, this standard has no bias.

11. Report

The report shall provide the following information:

• a) name of the sample;
• b) stability parameters: SE, P value and FRs1;
• c) compatibility parameters: the determined IN and SBN;
• d) the method used, i.e., this standard number;
• e) if the determination is carried out at a temperature above room temperature, give the temperature at the time of determination.

12. Referenced documents

• GB/T 4756 Petroleum liquids — Manual sampling
• GB 25989—2010 Fuel oils for burners
• GB/T 27867 Petroleum liquids — Automatic pipeline sampling
• GB/T 29114—2012 Gas turbine liquid fuels
• SH/T 0266 Determination of asphaltene content in petroleum
• NB/SH/T 0843 Statistical techniques for the evaluation of analytical testing systems in the petrochemical industry

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick Q&A Reference