1.1 本规程涵盖反渗透（RO）装置浓缩液流朗格利尔饱和指数的计算和调整。该指数用于确定碳酸钙（CaCo）的需求 3. )反渗透装置运行和设计中的规模控制。本规程适用于总溶解固体含量为10至10000 mg/L的浓缩液流。含10%以上的精矿 000 毫克/升，见实践 D4582 . 1.2 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。 1.3 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 在反渗透装置的设计和运行中，预测精矿流的碳酸钙结垢特性很重要。由于精矿流中总溶解固体的增加以及钙离子、碳酸氢根离子和游离二氧化碳通道的差异，精矿流的碳酸钙结垢特性通常与进料溶液的结垢特性大不相同。这种做法允许根据给水分析和反渗透操作参数计算浓缩液流的朗格利尔饱和指数。 5.2 正的Langelier饱和度指数表明有形成碳酸钙垢的趋势，这可能会损害反渗透性能。本规程给出了调整Langelier饱和指数的各种程序。 5.3 通过添加阻垢剂或晶体改进剂，可以抑制形成碳酸钙垢的趋势。抗血清和晶体改性剂的供应商可以提供有关这些类型化学品阻垢性能的信息。它们的使用可能适合于减少反渗透系统中的水垢形成。 在使用抗血清和晶体改性剂之前，应咨询反渗透系统供应商，以确保它们不会对反渗透系统产生负面影响。

1.1 This practice covers the calculation and adjustment of the Langelier saturation index for the concentrate stream of a reverse osmosis (RO) device. This index is used to determine the need for calcium carbonate (CaCo 3 ) scale control in the operation and design of RO installations. This practice is applicable for concentrate streams containing 10 to 10 000 mg/L of total dissolved solids. For concentrate containing over 10 000 mg/L, see Practice D4582 . 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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 In the design and operation of RO installations, it is important to predict the calcium carbonate scaling properties of the concentrate stream. Because of the increase in total dissolved solids in the concentrate stream and the difference in passages for calcium ion, bicarbonate ion, and free carbon dioxide, the calcium carbonate scaling properties of the concentrate stream will generally be quite different from those of the feed solution. This practice permits the calculation of the Langelier saturation index for the concentrate stream from the feed water analyses and the RO operating parameters. 5.2 A positive Langelier saturation index indicates the tendency to form a calcium carbonate scale, which can be damaging to RO performance. This practice gives various procedures for the adjustment of the Langelier saturation index. 5.3 The tendency to form calcium carbonate scale can be suppressed by the addition of antiscalents or crystal modifiers. Suppliers of antisealents and crystal modifiers can provide information on the scale inhibition peformance of these types of chemical. Their use may be appropriate for reducing scale formation in RO systems. The RO system supplier should be consulted prior to the use of antisealents and crystal modifiers to ensure they will not have a negative impact on the RO system.