13-12: Water Reuse – As Time Goes by do the Less Attractive Approaches

Reuse of lower quality waters as make-up water to Open Evaporative Cooling Water Systems has been implemented and practiced for several decades. The driving force was often “image”, lowering environmental impact, and/or economic benefits (reduced operating costs). Pareto’s Principle was often followed if not strictly applied, the easiest, lowest cost to implement approaches were those most often implemented. With the passage of time, more stringent restrictions on permitted discharge consents and/or increased cost or reduced availability of good quality water have emerged or developed in some parts of the world. This may have a significant impact upon the benefits and requirements of existing reuse applications and/or make the previously less attractive projects worth reconsidering. The additional requirements that current applications may require, more advanced techniques that may be used within reuse projects are discussed within this paper.