Book contents
- Frontmatter
- Dedication
- Epigraph
- Contents
- Foreword and Preface
- Preface
- Summary of the first global integrated marine assessment
- The context of the assessment
- Assessment of Major Ecosystem Services from the Marine Environment (Other than Provisioning Services)
- Assessment of the Cross-cutting Issues: Food Security and Food Safety
- Assessment of Other Human Activities and the Marine Environment
- Chapter 17 Shipping
- Chapter 18 Ports
- Chapter 19 Submarine Cables and Pipelines
- Chapter 20 Coastal, Riverine and Atmospheric Inputs from Land
- Chapter 21 Offshore Hydrocarbon Industries
- Chapter 22 Other Marine-Based Energy Industries
- Chapter 23 Offshore Mining Industries
- Chapter 24 Solid Waste Disposal
- Chapter 25 Marine Debris
- Chapter 26 Land-Sea Physical Interaction
- Chapter 27 Tourism and Recreation
- Chapter 28 Desalinization
- Chapter 29 Use of Marine Genetic Resources
- Chapter 30 Marine Scientific Research
- Chapter 31 Conclusions on Other Human Activities
- Chapter 32 Capacity-Building in Relation to Human Activities Affecting the Marine Environment
- Assessment of Marine Biological Diversity and Habitats
- Section A Overview of Marine Biological Diversity
- Chapter 36 Overview of Marine Biological Diversity
- Section B Marine Ecosystems, Species and Habitats Scientifically Identified as Threatened, Declining or Otherwise in need of Special Attention or Protection
- I Marine Species
- II Marine Ecosystems and Habitats
- Section C Environmental, economic and/or social aspects of the conservation of marine species and habitats and capacity-building needs
- Overall Assessment
- Annexes
- References
Chapter 28 - Desalinization
from Assessment of Other Human Activities and the Marine Environment
Published online by Cambridge University Press: 18 May 2017
- Frontmatter
- Dedication
- Epigraph
- Contents
- Foreword and Preface
- Preface
- Summary of the first global integrated marine assessment
- The context of the assessment
- Assessment of Major Ecosystem Services from the Marine Environment (Other than Provisioning Services)
- Assessment of the Cross-cutting Issues: Food Security and Food Safety
- Assessment of Other Human Activities and the Marine Environment
- Chapter 17 Shipping
- Chapter 18 Ports
- Chapter 19 Submarine Cables and Pipelines
- Chapter 20 Coastal, Riverine and Atmospheric Inputs from Land
- Chapter 21 Offshore Hydrocarbon Industries
- Chapter 22 Other Marine-Based Energy Industries
- Chapter 23 Offshore Mining Industries
- Chapter 24 Solid Waste Disposal
- Chapter 25 Marine Debris
- Chapter 26 Land-Sea Physical Interaction
- Chapter 27 Tourism and Recreation
- Chapter 28 Desalinization
- Chapter 29 Use of Marine Genetic Resources
- Chapter 30 Marine Scientific Research
- Chapter 31 Conclusions on Other Human Activities
- Chapter 32 Capacity-Building in Relation to Human Activities Affecting the Marine Environment
- Assessment of Marine Biological Diversity and Habitats
- Section A Overview of Marine Biological Diversity
- Chapter 36 Overview of Marine Biological Diversity
- Section B Marine Ecosystems, Species and Habitats Scientifically Identified as Threatened, Declining or Otherwise in need of Special Attention or Protection
- I Marine Species
- II Marine Ecosystems and Habitats
- Section C Environmental, economic and/or social aspects of the conservation of marine species and habitats and capacity-building needs
- Overall Assessment
- Annexes
- References
Summary
Introduction
Desalinization of seawater is an essential process for the support of human communities in many places around the world. Seawater has a salt content of around 35,000 parts per million (ppm) depending on the location and circumstances: to produce the equivalent of freshwater (with around 1000 ppm (AMS, 2014) therefore requires the removal of over 97 per cent of the salt content. The main purpose of desalinization is to produce water for drinking, sanitation and irrigation. The process can also be used to generate ultra-pure water for certain industrial processes. This chapter reviews the scale of desalinization, the processes involved and its social and economic benefits. Issues relating to discharges from desalinization plants are considered in Chapter 20 (Coastal, riverine and atmospheric inputs from land).
Nature, location and magnitude of desalinization
As Figure 28.1 shows, desalinization capacity has grown rapidly over the past half-century. About 16,000 desalinization plants were built worldwide between 1965 and 2011. About 3,800 of these plants are thought to be currently out of service or decommissioned. The current operational capacity is estimated to be about 65,200 megalitres per day (65,200,000 cubic metres per day (m3/d) – in comparison, the public water supply of New York City, United States of America, delivers in total about 3,800 megalitres per day) (GWI, 2015; NYCEP, 2014).
Historically, human settlements have tended to grow up where freshwater was available, and their growth has been conditioned by freshwater availability and the possibilities of bringing it to serve the settlement. As long ago as 312 BCE, the Romans had had to build a 16.4-kilometre aqueduct to bring water to Rome in order to avoid this constraint (Frontinus). Desalinization represents an alternative technology for avoiding this constraint on the growth of human settlements in areas with very limited availability of freshwater. That capability, however, comes at the price of considerable capital investment and energy consumption. Gleick et al. (2009) give an overview of the worldwide distribution of desalinization capacity in 2009.
The nature of the industry, however, varies in many ways between the different regions, particularly in respect of the technology used: the Middle East has relied more on thermal processes, while the United States has relied more on membrane processes. Thermal processes (mainly Multi-Stage-Flash (MSF) and Multiple-Effect-Distillation (MED)) evaporate the water and then re-condense it.
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- Information
- The First Global Integrated Marine AssessmentWorld Ocean Assessment I, pp. 441 - 450Publisher: Cambridge University PressPrint publication year: 2017