Increasing freshwater scarcity across the world means that wastewaterreclamation is being considered as a key method in which to meet the growingdemand. Evolution of water reuse schemes where high quality product isrequired such as for indirect potable reuse has led to the adoption in recentyears of the integrated membrane scheme using a combination of microfiltrationor ultrafiltration with reverse osmosis membrane. However, despitetechnological advancements, these membranes are still prone to foulingresulting in increased costs through cleaning or replacement. This thesis aimsto look at pretreatment to reduce the fouling propensity of the microfiltrationmembranes via a 600m3 /d pilot plant which was commissioned to investigateindirect potable reuse.A range of pretreatments including pre-screening, pre-coagulation, powderedactivated carbon and granular activated carbon were assessed based on foulingamelioration, water quality improvement and cost analysis. Results showed thatferric sulphate dosing was the most effective in terms of reducing the reversiblefouling rate especially at high turbidity loads enabling higher flux to be realisedleading to a small cost benefit. Activated carbon proved the most effectivepretreatment in terms of organic removal and a significant reduction in theirreversible fouling rate. However, the cost involved in using this as apretreatment is significant compared to possible cost savings through reducedrequirement for chemical cleaning. This pretreatment is only viable if it obviatesthe need for a separate organic removal process.
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