Water Conservation in Yarra Valley Water's Cooling Tower Systems
The aims of the study were to investigate the potential for saving water in cooling tower systems of five of Yarra Valley Water's industrial or commercial customers, then using this information to provide an estimation of the potential for saving water in all cooling tower systems in Yarra Valley Water's distribution zone. Through a systematic analysis the current operation, maintenance, monitoring and system control of the cooling tower systems as well as possible re-use water sources were investigated at the five sites. It was found through determining the current operational efficiency of the cooling towers that systems of smaller system volume, or inherent system size, were currently operating at the lowest efficiency with this efficiency increasing with the size of the system. Estimated improvements in the current efficiency lead to potential operational water reductions of between 142 kl/Yr and 953kL/Yr. Re-use water opportunities were also abundant with the majority of potential water coming from system water dumped to the sewer before system sterilisations which equated to water recovery of between 4 kL/Yr and 560 kL/Yr. Additional water re-use sources were also ascertained such as rain-water capture and process equipment flushing water. Through a combination of operational improvements and re-use of water, it was found that the total possible cooling tower system water reductions were between 244 kL/Yr and 1513 kL/Yr. Using the above, an estimate of the total water savings through all cooling tower systems was found to be 469 ML/Yr, equivalent to the average demand of 2376 household's in Yarra Valley Water's distribution area.