中文摘要：

水网络集成是过程工业一项重要的节水技术,如今受到越来越多的关注。固定流量过程与固定杂质负荷过程是工业水网络中典型的两类操作过程。不同于固定杂质负荷过程,固定流量过程是一类不涉及传质的用水操作单元。改进了针对固定杂质负荷过程的多杂质用水系统提出的浓度势概念,并将其应用于固定流量过程的多杂质用水系统设计。设计中各过程的执行顺序由需求水流的浓度势（CPD）决定：按照CPD值由小到大的顺序依次执行各过程。满足需求水流时,按照虚拟分配量由大到小的顺序来选择内部水源,按照价格由低到高的顺序选择外部水源。实例结果表明,该方法只需简单计算即可获得多杂质固定流量水系统的设计网络。

英文摘要：

Water network integration as an important water conservation technology has attracted more and more attention.The fixed flowrate operation and fixed contaminant load operation are two typical processes in industrial practice.Different from fixed contaminant load operations,fixed flowrate operations are the quantity controlled units that do not involve mass transfer.To consider recycling,this paper improves the concepts of the concentration potentials,which were proposed in the literature for fixed contaminant load systems with multiple contaminants.The improved concepts can be applied to targeting and design for the water system with multiple contaminants of fixed flowrate processes.In the design procedure,the performing order is determined by the values of concentration potential of demands（CPDs）： the process with the lowest CPD value should be performed first.While satisfying a demand stream,the internal sources streams with descending order of maximum quasi-allocation amounts will be considered first,and the external sources with descending order of cost will be used in turn.The results of the illustrated examples show that the method proposed can design fixed flowrate networks with multi-contaminant easily.It is shown that the proposed method is simple and effective.