考虑水质与水价影响的城市再生水需求研究

Demand analysis of urban reclaimed water considering water quality and water price

再生水是城市的“第二水源”,加强再生水配置利用对优化供水结构、增加水资源供给、缓解水量供需矛盾以及保障水生态安全具有重要意义。科学预测城市再生水需求是提高污水资源化利用水平的重要基础。在区域水资源需求分析基础上,充分考虑工业生产、城市杂用、河道补水、农林灌溉等4大领域的水量和水质需求特点,提出考虑水质与水价的分领域再生水需求预测技术框架。首先考虑水质影响,引入再生水可替代率指标,分析水资源需求总量中可由再生水供给的水量;其次,考虑自主定价模式下再生水价格对用户需求的影响,建立“补贴-价格-需求”模型,计算不同补贴情景下区域再生水的需求量;最后,应用于宿迁市中心城市。结果表明:在规划年2025和2030年的再生水利用率目标要求下,采用中等补贴情景能在有效推广再生水利用的同时兼顾政府财政压力,再生水需求量分别可达10095×10^(4)和13387×10^(4) m^(3)。本研究进一步拓展了城市再生水需求量预测的理论方法,也为宿迁市再生水利用配置提供了科学依据。

Reclaimed water is called the second water source of city;strengthening the allocation and utilization of reclaimed water is conducive to optimizing the water supply structure,increasing the supply of water resources,alleviating the contradiction between water supply and demand,and ensuring water ecological security.Scientific demand prediction of urban reclaimed water can provide a technical support for the improvement of wastewater resource utilization level.Based on the demand analysis of regional water resources,full consideration is given to the characteristics of quantity and quality of water demand in 4 fields,including industrial production use,urban miscellaneous use,river replenishment use,as well as farmland and forestry irrigation use.Then,a technical framework of demand prediction of reclaimed water in various fields is put forward based on the consideration of water quality and water price.Firstly,considering the influence of water quality,the index of the replaceable rate of reclaimed water is introduced to analyze the water quantity that can be supplied by reclaimed water in the total water demand.Secondly,considering the influence of the price on the demand of reclaimed water under the independent pricing mode,a subsidy-price-demand model is established to calculate regional reclaimed water demand under different subsidy scenarios.The case study of the central urban area of Suqian City show that under the requirements of the target utilization rate of reclaimed water in 2025 and 2030,the medium subsidy scenario can effectively promote the utilization of reclaimed water while balancing the financial pressure of the government,and the reclaimed water demand can reach 10095×10^(4) and 13387×10^(4) m^(3) respectively.This study provides a new addition to the theoretical methods of the demand prediction of urban reclaimed water,as well as a technical support for the utilization and allocation of reclaimed water in Suqian City.