海水淡化领域水足迹相关标准HY/T 0423-2024《海水淡化系统水足迹评价通则》、HY/T 0424-2024《海水淡化系统水足迹核算要求》于2024年9月13日获批发布。这是国内外首次将水足迹理论应用于海水淡化领域，是我国海水淡化与综合利用标准体系建设的重要内容。

制定背景

水资源是一切生命生存、人类社会发展和经济活动所不可或缺的重要基本条件。水资源短缺的问题使得各国政府开始通过其他途径来增加水资源的获取，海水淡化因为产水水质优良且可以就近解决沿海地区用水问题而备受关注。然而，海水淡化产业在快速发展的同时，其对各种能源物料的消耗以及浓盐水排放可能对环境造成了一定的影响，因此综合衡量海水淡化资源环境效益需求迫切。

水足迹是量化与评价水资源效益的有效工具。现有研究中，水足迹往往更多地被应用在农业、纺织业、畜牧业与工业产品的生产评价中，尚无在海水淡化中的应用。应用水足迹可以从水消耗和水污染等多个维度量化海水淡化厂生命周期对资源环境的影响，从而更全面地反映海水淡化对资源环境的影响。

主要内容

针对我国海水淡化量化评价缺失的问题，标准重点围绕反渗透膜法和低温多效蒸馏法两大典型海水淡化技术，根据海水淡化系统水足迹量化方法，制定海水淡化评价指南；从能源及水资源等角度，建立水足迹评价体系，识别海水淡化水足迹的关键影响因素，对不同规模、季节、工艺技术、能源对海水淡化系统水足迹的影响进行评价，量化海水淡化对资源环境带来的影响，为关键影响因素的优化提供建议，为海水淡化行业的发展方向提供新的思路。

HY/T 0423-2024《海水淡化系统水足迹评价通则》——该标准规定了海水淡化系统水足迹评价的术语和定义、概述、评价目的和范围、评价过程和报告，适用于反渗透海水淡化系统、低温多效蒸馏海水淡化系统水足迹评价，其他海水淡化系统可参考执行。

HY/T 0424-2024《海水淡化系统水足迹核算要求》——该标准规定了基于生命周期评价的海水淡化系统水足迹核算的术语和定义、核算原则、核算目的和范围的确定、水足迹清单分析、核算方法和报告，适用于反渗透海水淡化系统、低温多效蒸馏海水淡化系统水足迹的核算，其他海水淡化系统参照使用。

研究意义

该标准是贯彻落实我国海水淡化与综合利用标准化体系建设的一项重要标准，在国内外首次将水足迹理论应用于海水淡化领域，分析海水淡化系统产品水生产阶段与水相关的潜在环境影响，提供规范统一的水足迹核算和评价方法。对落实国家节水行动和发展战略，推动海洋标准体系的系统化、综合化建设有着重要的意义。

Our Chinese partner, Tianjin Desalination Institute, actively participated in the development of these standards, showcasing their leadership and innovation in the desalination field. Below are the details of the newly released standards:

Water Footprint Standards in the Field of Desalination

Two water footprint standards for desalination, HY/T 0423-2024: "General Principles for Water Footprint Evaluation of Desalination Systems" and HY/T 0424-2024: "Water Footprint Accounting Requirements for Desalination Systems", were approved and released on September 13, 2024.
These are the first standards globally to apply the water footprint theory to the field of desalination, marking a significant milestone in the construction of China's desalination and comprehensive utilization standards system.

Background

Water resources are essential for life, societal development, and economic activities. With water scarcity becoming a pressing issue, governments worldwide are exploring alternative means to increase water availability. Desalination has gained attention due to its ability to produce high-quality water and address coastal water shortages effectively.
However, the rapid growth of the desalination industry has raised concerns about its environmental impact, including energy and material consumption and brine discharge. A comprehensive evaluation of desalination’s resource and environmental benefits is urgently needed.

Water footprint analysis is an effective tool for quantifying and evaluating water resource efficiency. While the methodology has been extensively applied in agriculture, textiles, livestock, and industrial production, it has not yet been used in desalination. By incorporating water footprint analysis, the lifecycle resource and environmental impacts of desalination plants can be assessed from multiple dimensions, including water consumption and pollution, providing a holistic understanding of desalination's effects.

Key Content

The standards address the lack of quantitative evaluation methods for desalination in China and focus on two major technologies: reverse osmosis (RO) and low-temperature multi-effect distillation (MED).

·Evaluation Guidelines:
Develop guidelines for evaluating desalination systems based on water footprint quantification methods.
Establish a water footprint evaluation framework to identify key influencing factors, assess the impact of scale, season, technology, and energy use on desalination systems, and quantify their effects on resources and the environment.
Provide recommendations for optimizing key factors and offer new perspectives for the desalination industry’s development.

HY/T 0423-2024: "General Principles for Water Footprint Evaluation of Desalination Systems"

·Scope:
Defines terms, concepts, evaluation objectives, scope, processes, and reporting for water footprint evaluation.
Applicable to water footprint evaluations of reverse osmosis and low-temperature multi-effect distillation desalination systems. Other systems may refer to this standard.

HY/T 0424-2024: "Water Footprint Accounting Requirements for Desalination Systems"

·Scope:
Defines terms, principles, objectives, scope determination, inventory analysis, accounting methods, and reporting based on lifecycle assessment.
Applicable to water footprint accounting for reverse osmosis and low-temperature multi-effect distillation desalination systems. Other systems may use this standard as a reference.

Significance

These standards are pivotal in implementing China’s standardization framework for desalination and comprehensive utilization. They represent the first global application of water footprint theory to desalination systems, analyzing the potential environmental impacts associated with water production stages.
By providing unified methods for water footprint accounting and evaluation, these standards contribute to national water conservation strategies, promote systematic and integrated marine standardization, and support the sustainable development of desalination technology. Moreover, they enhance China’s influence in the international desalination field.