Environmental Effects of Large-scale Desalination Plants in the Middle East

Research output: Chapter in Book/Report/Conference proceedingPaper in conference proceeding

Abstract

The people bordering the Arabian Gulf, the Mediterranean Sea and the Red Sea rely more and more on seawater desalination for safe water supply. Desalination has advantages and disadvantages which to a large extent depend on the region, location, technology, impact and amount of fresh water production. In this region, some 60% of all desalination capacity is installed. The three regions areas represents about 11.8% of the world land area and the countries host approximately 9% of the world population in the three years 1950, 2008 and 2050. Arabian/Persian Gulf have been environmentally assessed by using wastewater and brine water. The Arabian Gulf region is occupying about 3.3% of the world area and about 2.0% of the total world population in 2008. The desalination capacities are about 50, 40 and 45% of total world capacity for the end of 1996, 2008 and 2050 respectively. With higher salinity in the Gulf, the exchange between the Gulf and the Ocean will increase. Mixing brine with wastewater dampens the water and salt exchange between the Gulf and the Ocean.
The environmental impacts of large-scale desalination plants must be understood properly in order not to cause new problems for the environment and people. For example, chemicals added in the pre-treatment stages of a desalination plant could harm the fish production as well as the marine life in general if disposed off uncontrolled. Largest environmental effect is attributed to the discharge of brines, i.e. remaining portion of the seawater when the freshwater part has been removed. For all desalination brines, the concentration of which is higher than that of the natural seawater normally returned to the sea. Concentrations of the brines are usually found to be double or close to double that of natural seawater. Location nearby coastline gives opportunities of choosing one or more outfall (building a series of outfalls) to the sea; it can minimize or reduce the environmental impact of brine discharge.
In this paper, the importance of correct brine discharge design will be analyzed and different methods on how to reduce negative effects of brine plumes in seawater reviewed. Brines are heavier than seawater due to the higher salt content. The increase in the recovery ratio is considered as one important factor in this study. In 1996 this ratio was about 30 to 35%, and in 2008 it was 40 to 45%, yet in some plants reaching up to 50%. Brine discharge will increase the salinities of the Arabian Gulf, Mediterranean Sea and Red Sea, with respectively some extra 2.24, 0.81 and 1.16 g/l in the year 2050.

Details

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Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Water Engineering

Keywords

  • Desalination plant small and large scale, Brine discharge, MENA region
Original languageEnglish
Title of host publicationWOCMES 2010
PublisherWOCMES 2010
Number of pages17
Publication statusPublished - 2010
Publication categoryResearch
Peer-reviewedNo
EventThird World Congress for Middle Eastern Studies (WOCMES), 2010 - Barcelona, Barcelona, Spain
Duration: 2010 Jul 192010 Jul 24
Conference number: 3

Conference

ConferenceThird World Congress for Middle Eastern Studies (WOCMES), 2010
Abbreviated titleWOCMES
CountrySpain
CityBarcelona
Period2010/07/192010/07/24