1.1 本试验方法包括通过使用光学装置的自动仪器对油中沥青质的最大絮凝率和油介质的胶溶能力进行量化的程序。 1.2 本试验方法适用于含有至少1 % 按质量计的沥青质。该试验方法尚未针对沥青开发。 注1: 光学探针检测絮凝沥青质的形成。当通过光学探针测量的信号变化率显著且持续增加时，可以解释絮凝的开始，确保絮凝正在进行。当样品中至少含有1.5%时，可以明确检测到絮凝开始 % 用试验方法测量的沥青质质量 D6560 . 注2: 本试验方法适用于典型规格的产品 D396页 -5L、5H和6级以及规格 D2880 -3-GT和4-GT级。 1.3 该试验方法在实验室间研究中进行了评估，最大絮凝率的标称范围为32至76，胶溶力的标称范围为36至95。 注3: 标称范围由（最小样品平均再现性）到（最大样品平均+再现性）确定。 1.4 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 沥青质是原油和含有残余物质的石油产品中的天然物质。沥青质通常存在于胶体悬浮液中，但如果沥青质分子的悬浮液因过度应力或不相容性而受到干扰，则它们可能会凝聚和絮凝。该试验方法提供了相容性参数，可用于评估稳定性储备和相容性。 5.2 当混合物的胶溶能力高于混合物的最大絮凝率时，认为混合物是稳定的； 3. , 4. 两者都可以使用经验混合规则计算。炼油厂和码头业主可以通过事先评估燃料的相容性来防止沥青质因不相容性而絮凝。 注4: 看见 附录X1 以预测兼容性为例。

1.1 This test method covers a procedure for quantifying the maximum flocculation ratio of the asphaltenes in the oil and the peptizing power of the oil medium, by an automatic instrument using an optical device. 1.2 This test method is applicable to atmospheric or vacuum distillation residues, thermally cracked residue, intermediate and finished residual fuel oils, containing at least 1 % by mass asphaltenes. This test method has not been developed for asphalts. Note 1: An optical probe detects the formation of flocculated asphaltenes. The start of flocculation is interpreted when a significant and sustained increase in rate-of-change of signal, as measured by the optical probe, ensures flocculation is in progress. The start of flocculation can be detected unambiguously when the sample contains at least 1 % mass asphaltenes as measured by Test Method D6560 . Note 2: This test method is applicable to products typical of Specification D396 —Grades 5L, 5H, and 6, and Specification D2880 —Grades 3-GT and 4-GT. 1.3 This test method was evaluated in an interlaboratory study in the nominal range of 32 to 76 for the maximum flocculation ratio and in the nominal range of 36 to 95 for peptizing power. Note 3: The nominal range is determined by (min. sample mean—Reproducibility) to (max. sample mean + Reproducibility). 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Asphaltenes are naturally occurring materials in crude petroleum and petroleum products containing residual material. The asphaltenes are usually present in colloidal suspensions, but they may agglomerate and flocculate if the suspension of asphaltene molecules is disturbed through excess stress or incompatibility. This test method provides compatibility parameters, which can be used to assess stability reserve and compatibility. 5.2 A blend is considered stable when the blend’s peptizing power is higher than the blend’s maximum flocculation ratio; 3 , 4 both of them can be calculated using empirical blend rules. Refineries and terminal owners can prevent the flocculation of asphaltenes due to incompatibility by assessing the compatibility of fuels beforehand. Note 4: See Appendix X1 for an example of prediction of compatibility.