1.1 本试验方法包括从1 mg/kg至250 在没有甲醇或其他防冻剂的情况下，使用在线电子水分分析仪（也称为电子湿度计或露点分析仪）测量mg/kg。 1.1.1 这些分析仪通常使用基于氧化铝、铝的传感元件 2. O 3. ，硅酮，五氧化二磷，P 2. O 5. ，压电式电池，或基于激光的技术来测量液化石油气的露点温度。 1.1.2 需要了解液化石油气的碳氢化合物成分，才能根据液化石油气样品的露点温度以质量为基础计算水含量。 1.1.3 液化石油气应不含酒精（有时作为防冻剂添加），因为它会干扰电子水分分析仪。因此，该方法在已知未向液化石油气产品中添加甲醇的工艺设施中最为有用。 1.2 以国际单位制表示的数值应视为标准值。 1.2.1 中有一个例外 附录X1 ，其中单位“mbar”用于外部来源提供的数据，百万分之一（ppm）在工业中广泛使用。 1.3 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。 1.4 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 液化石油气的含水量对液化石油气产品的使用、运输或加工至关重要，尤其是在寒冷的环境温度和压力节流期间，当结冰或水合物形成或两者都很可能发生时。 为了防止冰或水合物的形成，或两者兼而有之，含水量必须足够低，以防止在正常使用期间遇到的整个操作条件（温度、压力和成分）范围内，在储罐和/或调节器中形成游离水。例如，丙烷和丙烷-丙烯混合物要求这些碳氢化合物在工作温度和压力下的水分水平低于水的平衡饱和水平，以满足规范，如 D1835 . 5.2 丙烷系统中存在游离水会导致冰或水合物积聚，堵塞蒸汽或液体燃料管线，并干扰泵、仪表、过滤器、阀门、调节器、安全阀的运行- 关闭阀和其他设备。 5.3 该试验方法允许连续监测工艺流程，如果已知未添加甲醇，则可用于监测运输操作期间的产品干燥度。

1.1 This test method covers the quantitative determination of water in liquefied petroleum gases (LPG) from 1 mg/kg to 250 mg/kg using an online electronic moisture analyzer, also known as an electronic hygrometer or dew point analyzer, in the absence of methanol or other anti-freeze agent. 1.1.1 These analyzers commonly use sensing cells based on aluminum oxide, Al 2 O 3 , silicone, phosphorus pentoxide, P 2 O 5 , piezoelectric-type cells, or laser-based technologies to measure the dew point temperature of LPG. 1.1.2 Knowledge of the hydrocarbon composition of the LPG is required to calculate the water content on a mass basis from the dew point temperature of an LPG sample. 1.1.3 The LPG shall be free of alcohol (sometimes added as an anti-freeze agent) as it can interfere with the electronic moisture analyzer. Thus the method will be most useful in a process facility where it is known that no methanol has been added to the LPG product. 1.2 The values stated in SI units are to be regarded as standard. 1.2.1 There is an exception in Appendix X1 , where the unit “mbar” is used in data provided by an external source, and parts per million by weight (ppm by weight) is widely used in industry. 1.3 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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 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 The moisture content of LPG can be critical to the use, transportation, or processing of LPG products, especially at cold ambient temperatures and during pressure throttling, when icing or hydrate formation, or both, are most likely to occur. In order to prevent ice or hydrate formation, or both, the water content has to be low enough to prevent the formation of free water in storage tanks and/or regulators over the entire range of operating conditions (temperatures, pressures, and compositions) encountered during normal service. For example, propane and propane-propene mixtures require moisture levels below the equilibrium saturation level of water at operating temperature and pressure for these hydrocarbons to meet specifications such as Specification D1835 . 5.2 The presence of free water in a propane system can lead to ice or hydrate accumulation, the blockage of vapor or liquid fuel lines, and disrupt the operation of pumps, meters, filters, valves, regulators, safety shut-off valves, and other equipment. 5.3 This test method allows continuous monitoring of process flow streams and could be applied to monitoring of product dryness during transportation operations if it is known that methanol has not been added.