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Brief Book Summary Introduction
Pretreatment is an integral part of every desalination plant. The level and complexity of the needed pretreatment mainly depend on the concentration and type of particulate, colloidal, and dissolved organic foulants contained in the source seawater. At present, granular media filtration is the dominating technology for pretreatment. In the last 10 years, however, membrane pretreatment is emerging as an attractive alternative to gran- ular media filtration.
This type of pretreatment is gaining a wider acceptance mainly due to its superior removal of particulate and colloidal foulants and its benefits in terms of consistent and reliable performance, and operational flexi- bility. Membrane pretreatment, however, is usually more costly than granular media filtration and has a very limited ability to
remove easily biodegradable organics asso- ciated with algal blooms, which in most cases are the main culprit for reverse osmosis membrane fouling. Therefore, at its present state of development, MF- and UF tech- nologies do not always offer the most viable and cost-effective solution for saline water pretreatment.
Taking under consideration the numerous factors affecting the overall pretreatment costs of a full-scale desalination plant, the selection of the most suitable pretreatment system for a given desalination project should be completed based on a thorough, site-specific, life-cycle cost analysis, which accounts for all expenditures and actual costs associated with the installation and oper- ation of membrane and granular media pretreatment systems.
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