一、前言城市用水包括工业用水和生活用水两大类,工业用水需水量是指工业生产过程中引用水量和重复利用水量之和。生活用水一般包括城镇民居生活用水和城镇公共生活用水两个部分,其中公共生活用水是指城镇中的机关、学校、商店、旅馆、医院和公共场所等部门的用水,以及消防、环境净化、绿地浇灌、输水损失等其它用水。城市用水的水源一般均由江、河、湖、泊及地表层以下通过水泵抽引提供,它是城市耗能的重要组成部分,因此城市节水也是节能的重要内容。城市用水除自然蒸发和转化损失一部分外,其中大部分是以污水排 I. Preface Urban water use includes two major categories of industrial water and domestic water. The industrial water demand refers to the sum of the quoted and reused water in industrial production. Domestic water generally includes urban residential water and public water for urban life in two parts, of which public living water refers to the towns in the organs, schools, shops, hotels, hospitals and public places and other departments of the water, as well as fire, environmental purification, green Watering, water loss and other water. Water supply for urban water supply is generally provided by pumping pumps below the river, river, lake, moor and surface and is an important part of the city’s energy consumption. Therefore, urban water conservation is also an important part of energy conservation. Except for natural evaporation and conversion losses, most of the water in urban areas is discharged by sewage