Introduction and feasibility assessment of laundry use of recycled water in dual reticulation systems in Australia

Laundry is a potential new end use of recycled water in dual reticulation systems. Generally, the community is willing to accept this new end use if it can meet the concerns on health issues, durability of washing machine, cloth quality and aesthetic appearance. This study addresses all these major concerns thereby assisting in the introduction and promotion of this new end use in the existing and proposed dual reticulation systems. Five representative cloth materials were selected for washing in tap water and in recycled water for up to 50 wash cycles for comparative studies. The tearing/tensile strength tests were used for the assessment of cloth durability. ANOVA one way test was applied for the significance analysis (Tukey's test p<0.05) which indicated that there is no significant change in the tensile/tearing strengths of washed cloth samples. Scanning electron microscope (SEM) images of the washed cloth samples found no distinct change in surface morphology. Textile colour analysis (CIEDE2000) analysed the variation in colour of the washed cloth samples and showed that the change in colour ∆E ranges from 0-1 revealing no visible difference in colour of cloth samples. Langelier Saturation Index (LSI) was used as the indicator for predicting corrosive/scaling potential of recycled water. The LSI values ranged from +0.5 to -0.5, indicating no corrosive or scaling potential of recycled water. The microbiological study of the cloth samples washed in recycled water indicated that there was no contamination with representative bacteria. As the recycled water has similar effects like tap water on cloth and washing machine, it is safe to use for laundry.