Based on the insight that the difference between the water network involving regeneration and that involving reuse only is that there is an additional stream

the regenerated stream

in the former one

this paper presents an iterative method for designing water-using networks of single contaminant involving regeneration reuse/recycling.For the networks with a given removal ratio(RR)

a reasonable regeneration concentration is obtained first.Add the regenerated stream into the network with reuse only

the network involving regeneration can be formed.Then the design of the networks involving regeneration reuse/recycling can be performed by using the design procedure proposed for the systems involving reuse only.For the networks with the given regeneration concentration

the final design can be obtained with one iteration.For the networks with a known removal ratio

the final design can be obtained with several iterations.This paper considers the targets of freshwater consumption

regenerated water flow rate

and mass load for regeneration

and all the target items can reflect the total cost of the network.A few literature examples are investigated.The structures of the designs obtained in this work are not complex compared to that reported in the literature

and the calculation of the proposed method is very simple.