Design of water-using networks of multiple contaminants with two internal water mains

• New method for design of water-using networks with two internal water mains.
• A conventional network without internal water mains is obtained first.
• Divide processes into three parts to form initial structure.
• Final design can be obtained in a few iterations.
• The designs obtained in this work are comparable to that obtained in the literature.

This paper presents a new method for design of water-using networks with two internal water mains. A conventional water-using network without internal water mains is obtained first by using the concentration potential method. The processes are divided into three parts to form an initial structure of the water-using network with two internal water mains, based on the features of the conventional water-using network obtained. The final design can be obtained in a few iterations by adjusting the amounts of the internal water mains. The results of a few literature examples show that the designs obtained in this work are comparable to that obtained in the literature. The significance of the work presented is that all the design steps, including the formation and adjustment of the internal water mains, are orientated with clear engineering meanings, which are expressed by the values of concentration potentials.