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Analysis and Modelling of Desalination Brines

Bashitialshaaer, Raed LU (2011) In LUTVDG/(TVVR-1052)(2011) 1052.
Abstract (Swedish)
Popular Abstract in Swedish

Avsaltning av havsvatten utgör en viktig källa för vattenförsörjning till befolkningen som bor

vid Persiska viken, Medelhavet och Röda havet. De tre regionerna utgör ca 11,8 % av världens

landyta och hade omkring 9 % av världens befolkning under 1950 och 2008, samt lika mycket

enligt prognos för år 2050. Dessa områden är hemvist för 62 %, 58% och 60% av världens

avsaltningskapacitet för år 1996, 2008 respektive 2050. Utbytet av dricksvatten ur havsvatten

har identifierats som en viktig faktor i denna studie. Under 1996 uppgick utbytet till cirka 30-35

% och år 2008 var det cirka 40-45 %, medan vissa avsaltningsanläggningar nådde upp till... (More)
Popular Abstract in Swedish

Avsaltning av havsvatten utgör en viktig källa för vattenförsörjning till befolkningen som bor

vid Persiska viken, Medelhavet och Röda havet. De tre regionerna utgör ca 11,8 % av världens

landyta och hade omkring 9 % av världens befolkning under 1950 och 2008, samt lika mycket

enligt prognos för år 2050. Dessa områden är hemvist för 62 %, 58% och 60% av världens

avsaltningskapacitet för år 1996, 2008 respektive 2050. Utbytet av dricksvatten ur havsvatten

har identifierats som en viktig faktor i denna studie. Under 1996 uppgick utbytet till cirka 30-35

% och år 2008 var det cirka 40-45 %, medan vissa avsaltningsanläggningar nådde upp till hela

50 %. Runt Persiska viken fanns och finns 50 %, 40 % och 45 % av världens totala

avsaltningskapacitet i slutet av 1996, 2008 respektive 2050 (prognos).

Alla länder i Mellanöstern lider av brist på vattenresurser samtidigt med en ökad efterfrågan av

vatten på grund av den höga befolkningstillväxten. Avsaltning kan vara ett kostnadseffektivt

sätt att producera färskvatten och möjligtvis också el. En lösning för Sinai och Gazaremsan

föreslås som innebär att en gemensam kraft- och avsaltningsanläggning uppförs i Egypten nära

gränsen till Gazaremsan. Detta gemensamma Egypten-Palestina projekt skulle öka

vattenförsörjningen med 500 000 m3/d och kraftförsörjningen med 500 MW i regionen.

Resultatet från fältarbete och två experiment i laboratorieskala redovisas. De kan även tillämpas

för att utforma detta projekt. Massbalanser för vatten och salt för Döda havet modellerades

genom att inkludera och exkludera vatten från ett föreslaget projekt att överföra vatten från

Röda havet till Döda havet i en kanal (RSDSC). Nederbörd, avdunstning, ytvattenflöde,

grundvattenflöden, samt uppgifter för tillflöde och avlopp från mineralutvinningsföretag runt

Döda havet användes i modellen. Blandningstiden i Döda havet modellerades genom att

använda två olika ekvationssystem, för väl omblandade respektive skiktade förhållanden.

En effektiv metod för att påskynda utspädningen av det salta rejektvattnet från

avsaltningengsverket i recipienten är att använda en vinklad utgångsstråle eller spridning med

multipla utlopp. Två experimentella studier i laboratorieskala utfördes för att undersöka hur en

tung/tät stråle fördelades i omgivande vatten. Den första studien gjordes med vinklade

tunga/täta strålar för att studera betydelsen av utloppsstrålens vinkel, där lutningen ökade för de

maximala nivåerna som funktion av denna vinkel. En utloppsvinkel på 60 grader ger snabbare

inblandning än 30 eller 45 grader. En empirisk relation för effektiv inblandning togs fram som

funktion av fem geometriska parametrar, vilken kan användas för framtida planering.

Fältundersökningar har gjorts på Cypern av hur rejektplymer från Eastem Mediterranean

Universitys avsaltningsanläggning fördelas lokalt i Medelhavet. Mätningarna visar att det

behövs mer än ett utlopp (multipla utlopp) ut till havet för att undvika eller minimera

miljöpåverkan längs kusten. Resultatet överensstämde väl med en enkel två-dimensionell

matematiska modell för spridning om plymen antas vara normalfördelad. Den beräknade

bottenlutningen i fält var låg, omkring 7,4 %, vilket delvis kan förklara varför smuts från

avsaltningen syntes på stranden i närheten av utsläppspunkten.

Ett andra laboratorieexperiment gjordes för att undersöka hur flödesfältet från tunga

saltvattenplymer såg ut nära utloppet och i mellanzonen innan plymen fördelats ut i recipienten.

Utspädningen längs plymen ökade med cirka 10 % och 40 % om botten lutade respektive om

botten lutade och strålen riktades 30 grader upp från horisontalplanet. Resultat av denna studie

kan användas för konstruktion av utlopp från avsaltningsverk för att minimera

saltkoncentrationsskillnader och för att få plymen att spädas ut snabbare och mera i recipient.

Mer än 16 % bottenlutning rekommenderas, liksom flera fältmätningar. En utloppsvinkel på 30

grader med 16 % bottenlutning ger mindre miljöpåverkan. De geometriska effekterna kan

modelleras framgångsrikt i Matlab. (Less)
Abstract
Seawater desalination constitutes an important water supply to the population bordering the Arabian Gulf, the Mediterranean Sea and the Red Sea. The three regions represent about 11.8% of the world land area and the countries
hosted approximately 9% of the world population in 1950 and 2008 and are also projected to do so in 2050. The results obtained for desalination capacity in the study area were 62%, 58% and 60% of the world capacity for 1996, 2008, and 2050, respectively. The increase in the recovery ratio is considered an important factor in this study. In 1996 this ratio was about 30 to 35%, and in 2008 it was 40 to 45%, although in some plants it reached up to 50%. The gulf desalination capacities were obtained as 50, 40 and 45%... (More)
Seawater desalination constitutes an important water supply to the population bordering the Arabian Gulf, the Mediterranean Sea and the Red Sea. The three regions represent about 11.8% of the world land area and the countries
hosted approximately 9% of the world population in 1950 and 2008 and are also projected to do so in 2050. The results obtained for desalination capacity in the study area were 62%, 58% and 60% of the world capacity for 1996, 2008, and 2050, respectively. The increase in the recovery ratio is considered an important factor in this study. In 1996 this ratio was about 30 to 35%, and in 2008 it was 40 to 45%, although in some plants it reached up to 50%. The gulf desalination capacities were obtained as 50, 40 and 45% of total world capacity at the end of 1996, 2008 and 2050 (prognosis) respectively.
All Middle Eastern countries suffer from a shortage of water along with increasing demand due to high population growth. Desalination can be a cost-effective way to produce fresh water and possibly electricity. A suggested solution for Sinai and the Gaza Strip involves the building of a joint power and desalination plant, located in Egypt close to the border with Gaza. This joint Egypt-Palestine project would increase the water supply by 500,000 m3/d and the power supply by 500MW. The result emerged from field work and the two experiments can also be applied to the design of this project. Water and salt mass balances for the Dead Sea were modelled by including and excluding the water from the proposed Red Sea Dead Sea Canal project, RSDSC. Precipitation, evaporation, river discharges, ground water flows, input/output from potash companies and salt production in addition to brine discharge were included in the models. The mixing time in the Dead Sea was modelled using a single-layer (well-mixed) and a two-layer (stratified) system.
An efficient method for increasing the dilution rate of brine water discharged into the sea is an inclined negatively buoyant jet of a single port or multi-diffuser. Two small-scale experimental studies were conducted to investigate the behaviour of a dense jet discharged into lighter ambient water. The first lab-scale experiment concerned the benefit of the initial angle of inclined dense jets, where the slope increased for the maximum levels as a function of this angle. An angle of 60 deg. led to a better result than 30 or 45 deg. An empirical prediction was found based on five geometric quantities to be considered in the future plan.
Field work measurements have been conducted in Cyprus, where the brine from a desalination plant and the Mediterranean Sea coastline have been investigated at the Eastern Mediterranean University. The result from the measured data demonstrates the need for more than one outfall (a series of outfalls) to the sea to avoid or minimize environmental impact on the coastline. The result also agreed well with simple, two dimensional mathematical models assuming Gaussian distribution. The calculated bottom slope is about 7.4%, which can explain the pollution that appears at the coast close to the discharge point. Thus small slope could be one reason.
The second lab-scale experiment studied the near and intermediate fields of negatively buoyant jets. The dilution along the flow was increased by about 10% and 40% with bottom slope and bottom slope together with a 30 degree jet
inclination, respectively. This method can be applied in brine discharge outlets to recipients to minimize concentration and facilitate faster and greater dilution. Over 16% bottom slope and more field work is needed for comparison with this result. It was found that an inclination of 30 degrees with 16 % bottom slope was more sustainable in designing brine discharge outfall. A Matlab code can be used to describe the lateral spreading and centerline dilution of buoyant jets and plumes in near and intermediate fields.
(Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Bergdahl, Lars, Inst för Vattenbyggnad, Chalmers tekniska högskola, Göteborg
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Modelling., Field data analysis, Negatively buoyant jet, Experiment, Brine discharge, Desalination, Water supply
in
LUTVDG/(TVVR-1052)(2011)
volume
1052
edition
1052
pages
211 pages
publisher
Lund University
defense location
Department of Building and Environmental Technology, John Ericsson väg 1, lecture hall V:B
defense date
2011-03-21 10:15
ISSN
1101-9824
ISBN
978-91-7473-058-6
language
English
LU publication?
yes
id
73bf9966-0f53-4ae5-948c-f12678777d13 (old id 1788450)
date added to LUP
2011-02-21 10:58:36
date last changed
2016-09-19 08:44:45
@phdthesis{73bf9966-0f53-4ae5-948c-f12678777d13,
  abstract     = {Seawater desalination constitutes an important water supply to the population bordering the Arabian Gulf, the Mediterranean Sea and the Red Sea. The three regions represent about 11.8% of the world land area and the countries<br/>hosted approximately 9% of the world population in 1950 and 2008 and are also projected to do so in 2050. The results obtained for desalination capacity in the study area were 62%, 58% and 60% of the world capacity for 1996, 2008, and 2050, respectively. The increase in the recovery ratio is considered an important factor in this study. In 1996 this ratio was about 30 to 35%, and in 2008 it was 40 to 45%, although in some plants it reached up to 50%. The gulf desalination capacities were obtained as 50, 40 and 45% of total world capacity at the end of 1996, 2008 and 2050 (prognosis) respectively.<br/>All Middle Eastern countries suffer from a shortage of water along with increasing demand due to high population growth. Desalination can be a cost-effective way to produce fresh water and possibly electricity. A suggested solution for Sinai and the Gaza Strip involves the building of a joint power and desalination plant, located in Egypt close to the border with Gaza. This joint Egypt-Palestine project would increase the water supply by 500,000 m3/d and the power supply by 500MW. The result emerged from field work and the two experiments can also be applied to the design of this project. Water and salt mass balances for the Dead Sea were modelled by including and excluding the water from the proposed Red Sea Dead Sea Canal project, RSDSC. Precipitation, evaporation, river discharges, ground water flows, input/output from potash companies and salt production in addition to brine discharge were included in the models. The mixing time in the Dead Sea was modelled using a single-layer (well-mixed) and a two-layer (stratified) system.<br/>An efficient method for increasing the dilution rate of brine water discharged into the sea is an inclined negatively buoyant jet of a single port or multi-diffuser. Two small-scale experimental studies were conducted to investigate the behaviour of a dense jet discharged into lighter ambient water. The first lab-scale experiment concerned the benefit of the initial angle of inclined dense jets, where the slope increased for the maximum levels as a function of this angle. An angle of 60 deg. led to a better result than 30 or 45 deg. An empirical prediction was found based on five geometric quantities to be considered in the future plan.<br/>Field work measurements have been conducted in Cyprus, where the brine from a desalination plant and the Mediterranean Sea coastline have been investigated at the Eastern Mediterranean University. The result from the measured data demonstrates the need for more than one outfall (a series of outfalls) to the sea to avoid or minimize environmental impact on the coastline. The result also agreed well with simple, two dimensional mathematical models assuming Gaussian distribution. The calculated bottom slope is about 7.4%, which can explain the pollution that appears at the coast close to the discharge point. Thus small slope could be one reason.<br/>The second lab-scale experiment studied the near and intermediate fields of negatively buoyant jets. The dilution along the flow was increased by about 10% and 40% with bottom slope and bottom slope together with a 30 degree jet<br/>inclination, respectively. This method can be applied in brine discharge outlets to recipients to minimize concentration and facilitate faster and greater dilution. Over 16% bottom slope and more field work is needed for comparison with this result. It was found that an inclination of 30 degrees with 16 % bottom slope was more sustainable in designing brine discharge outfall. A Matlab code can be used to describe the lateral spreading and centerline dilution of buoyant jets and plumes in near and intermediate fields.<br/>},
  author       = {Bashitialshaaer, Raed},
  isbn         = {978-91-7473-058-6 },
  issn         = {1101-9824},
  keyword      = {Modelling.,Field data analysis,Negatively buoyant jet,Experiment,Brine discharge,Desalination,Water supply},
  language     = {eng},
  pages        = {211},
  publisher    = {Lund University},
  school       = {Lund University},
  series       = {LUTVDG/(TVVR-1052)(2011)},
  title        = {Analysis and Modelling of Desalination Brines},
  volume       = {1052},
  year         = {2011},
}