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viii PREFACE
membrane desalination, such as the nature, origin, and characterization of key membrane foulants, the diagnostics of RO membrane fouling, the impact of the type of the desali- nation plant intake on the source water fouling potential and the configuration of the pre- treatment system, the most commonly used source-water screening technologies and equipment, source-water conditioning for pretreatment, sand removal, clarification by gravity settling and dissolved air flotation, and saline source water granular media and membrane filtration. In addition, the book provides a comparative analysis of membrane pretreatment and includes guidelines for pre- treatment system selection.
The book also includes guidance and ex- amples for sizing and cost estimation of key desalination-plant pretreatment facilities. It is important to underline that the facility and equipment procedures presented in this book are not intended to serve as standard, all-inclusive design procedures, but their main purpose is to illustrate typical meth- odologies and approaches used by desali- nation professionals. References to particular technologies, equipment and membrane manufacturers should not be construed as an endorsement by the author or a recommen- dation for a preferential use or consideration.
Cost graphs incorporated in this book are recommended to be used only for the prep- aration of initial order-of-magnitude esti- mates of the construction costs of the respective pretreatment systems and are presented in 2017 US dollars. Site-specific project conditions, currency differences, and other factors may result in significant dif- ferences between the actual facility con- struction costs and the value of these costs determined using the cost graphs of this book. The reader is recommended to contact the suppliers of the specific pretreatment
technologies, which are planned to be used for their desalination project in order to receive updated costs commensurate with local and international market conditions at the time of project implementation.
The book includes a total of 12 chapters, which follow the typical sequence of saline source-water pretreatment prior to mem- brane desalination and guide the reader to- ward the selection of the most suitable pretreatment technology or combination of technologies for the site-specific conditions of a given project. As indicated previously, the main emphasis of this book is the pre- treatment of seawater for RO desalination.
Chapter 1 provides a brief overview of the key reasons of why seawater pretreatment is needed prior to membrane desalination. The chapter mainly emphasizes the role of pretreatment in the production of desali- nated water and the interrelation of pre- treatment system and other desalination plant components.
Chapter 2 describes the type of foulants typically contained in source seawater or brackish water and explains how these fou- lants impact RO-membrane performance. In addition, this chapter discusses the most common methods presently employed worldwide to characterize the RO-membrane fouling potential of saline waters and iden- tifies threshold levels for key source-water quality parameters that trigger accelerated membranefouling.
Chapter 3 features an overview of the typical RO-membrane fouling phenomena observed in full-scale desalination systems and the methods used for diagnostics of the type and severity of membrane fouling. The chapter also illustrates the use of RO-membrane au- topsy for membrane fouling diagnostics.
Chapter 4 discusses the impact of the type and configuration of the desalination plant