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Desalination: an imminent solution for the future water needs in the Aqaba Special Economic Zone (ASEZ)
DESALINATION ELSEVIER
Desalination 152 (2002) 27-39 www.elsevietcom/locate/desal
Desalination: an imminent solution for the future water needs in the Aqaba Special Economic Zone (ASEZ) Samir F. Dweiri”*, Mohammad I. Badranb* 0Environmental Commission, Aqaba Special Economic Zone Authority, Jordan Tel. +962 (3) 2091000; Fax +962 (3) 2014204; email: [email protected] hA4arine Science Station, University of JoraWXarmouk Universily, Aqaba, Jordan Tel. +962 (3) 2015144; Fax +962 (3) 2OI3674; email: [email protected]
Received 25 April 2002; accepted 3 May 2002
Abstract
Jordan has recently given distinguished attention to its single and extremely limited sea outlet - Aqaba. An innovative governing system is being established. Aqaba has been declared as a Special Economic Zone Authority. The main objectives of the new authority are to develop Aqaba as a haven for commerce, a destination for tourism, and an incubator for technology. A strong limiting factor to this ambitious planning is the scarcity of fresh water. The conventional water resources utilized to satisfy the increasing water demand will reach the maximum sustainable yield in less than 5 years. At present, water supply is abstracted from groundwater aquifers and amounts to about 16.4 million m3/y (MCM/y). According to the final master plan of the ASEZA, the total consumption is expected to increase by about 5 MCM/y in the first 5 years, 11 MCM/ y in the following 5 years, and about 30 MCM/y by the end of 20 years. The ultimate allocation for ASEZA from the conventional water recourses from the Disi non-renewable aquifer does not exceed 17.5 MCM/y. This identified gap in water supply has defmitely to be filled by unconventional water resources such as desalination of seawater and brackish water. The location of ASEZ alongside the Red Sea and over partly brackish aquifers does qualie it for desalination. However, the ASEZA Environmental Commission is currently identifying significant issues to be considered in the mitigation measures when designing desalination plants in order to alleviate adverse environmental impacts to the ecosystem. This paper discusses the expected future water demands, the ASEZA acceptable water standards for the different water uses, and the environmental impact of the desalination plants and their respective mitigation measures. Keywords:
Demand and population forecast; ASEZA water needs; Environmental impact assessment; Groundwater resources; Marine life; Desalination; Mitigation measures
*Corresponding author. Presented at the EuroMed 2002 conference on Desalination Strategies in South Mediterranean Countries: Cooperation between Mediterranean Countries of Europe and the Southern Rim ofthe Mediterranean. Sponsored by the European Desalination Society and Alexandria University Desalination Studies and Technology Center, Sharm El Sheikh, Egypt, May 4-6, 2002. 001 l-9164/02/$-
See front matter 0 2002 Elsevier Science B.V. All rights reserved
PII: SOOll-9164(02)01045-7
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S.F Dweiri. MI. Badran /Desalination
I52 (2002) 27-39
1. Introduction
2.50 Tourist
With the launch of the Aqaba Special Economic Zone in May 17, 2001 and the international inauguration, Aqaba will experience an increase in population and consequently in water demand. The zone was declared as a haven for commerce, tourism and technology. This will result in an expected rise in water consumption for tourism,
industry as well as the domestic purposes. ASEZA is currently working on estimating the water resources and needs in the zone to better predict the water consumption and provide water for all the different uses in an environmentally sustainable way. At present the population of the zone is around 75,000. The current water consumption (year 2001) amounted to 11.2 MCM and is distributed between residential, industrial, commercial, tourist and agricultural as 35.3,35.2,7,2.5 and 20% respectively. Fig. 1 illustrates this distibution. Table 1 shows the year 2001 water consumption and the distribution for the water consumption in ASEZ. According to the Ministry of Water and Irrigation policy, any future supply exceeding the capacity of the Disi pipeline will be ensured from sources other than the Disi aquifer. It suggests the use of non-conventional water like desalination of seawater and brackish water [ 11.
Table 1 Water consumption and total produced water
Water use
Total Supplied water Produced water (all aquifers)
Residential
Fig. 1. Percentage of water consumption distribution ASEZ in 200 1,
in
2. Constraints on natural water resources In the Aqaba zone, the only water resource comes from the groundwater. Four main distinctive aquifers are identified. They are the Disi, Wadi Yutum, Wadi Araba, and Dirreh aquifers. The Disi aquifer is considered a non-renewable aquifer, while the others are renewable. According to several studies on the water resources in Aqaba, there is a virtual consensus that, with the exception of the Disi and the Yutum aquifers, the groundwater is mostly brackish or contaminated and cannot be used for municipal purposes without
in the Aqaba Special Economic Zone (MCM/y) in 2001
Consumption, MCM Quantity, MCM
Industrial Residential Commercial and services Agricultural Tourist
35.29
Total, %
% of supplied water % of produced water
3.95 3.96 0.79 2.25 0.28
35.18 35.29 6.99 20.04 2.50
27.70 27.79 5.50 15.78 1.97
23.97 24.04 4.76 13.65 1.70
11.23 14.26 16.48
100.00
78.74 100.00
68.13 86.53 100.00
29
S.E Dweiri. M. I. Badran / Desalination 152 (2002) 27-39
the supplied water and 32% of the total produced water. The unaccounted-for water includes the water theft, metering errors, and leakage from the pipes. The illegal use and water theft will be considered, for the purpose of this paper, part of the demand. Therefore, the recovery of the unaccounted-for water will not be regarded as an extra resource in the future, especially, since more studies are required to determine the actual physical leakages from the system.
treatment. According to the Ministry of Water and Irrigation, the maximum [2] allocation from the Disi aquifer to Aqaba shall not exceed the maximum capacity of the existing pipeline of 17.5 MCM/y. A recent World Bank study [3], has declared the groundwater safe yields as 5.5 MCMly for Wadi Yutum, 8.5 MCMly for Wadi Araba aquifer and 3.5 MCM/y for Dirreh Aquifer, of which only the waters of Wadi Yutum can be considered fresh water. In 200 1, the abstraction from all aquifers was about 16.5 MCM, of which 13.6 MCM was abstraction from the Disi aquifer. The maximum fresh water resource available for Aqaba amounts to about 23 MCMIy. About 9.5 MCM remains to be utilized from the Disi and the Yutum aquifers in the future. However, without the development of Wadi Yutum aquifer, the unutilizable water resources amount is 4 MCM/y.
4. Population, water demands and future forecasts and gaps In 1994, a complete census was conducted in Aqaba by the Jordan Department of Statistics in which the population was counted as 79,839 people [4]. Using a growth rate of 2.8%, the forecasted population was calculated as 85,080 for the ASEZ area in 2000. The latest population projections of the ASEZA Master Plan and other projections [5,6] are shown in Table 2. Fig. 2 illustrates the low and high population forecasts for ASEZ.
3. Water supply and unaccounted-for water In year 2001, about 14.2 MCM was supplied to consumers from the total fresh water production of 16.5 MCM. Of this quantity, 5.3 MCM is unaccounted-for water, which constitutes 37% of
Table 2 Aqaba special economic zone ASEZ projected population and projected water demand Year
2000
2005
2010
2015
2020
2025
ASEZ population (low projections) ASEZ population (high projections) Consumption per capita (I/c/p) (low projection) Consumption per capita (l/c/p) (high projection) Water demand (low projection), MCM/y Water demand (high projection), MCM/y Available water resource with Yutum, MCMly Available water resource without Yutum, MCM/y Water demand gap, MCM/y Desalination capacity Total available water resource with desalination, MCMfy
74,365 79,33 1 501
113,369 115,608 428
132,808 165,524 431
149,579 235,679 484
172,244 300,000 520
186,468 325,000 582
470
758
760
697
648
658
13.6 13.6 23
17.7 32 23
20.9 45.9 23
26.4 60 23
32.7 71 23
39.6 78 23
17.5
17.5
17.5
17.5
17.5
17.5
0 0
0.2 2 19.5
3.4 5 22.5
8.9 10 27.5
15.2 20 37.5
22.1 25 42.5
17.5
30
S.F Dweiri, ML Badran /Desalination 350000
-+ ASEZ
f
Population (low pmjections)
300000 “I ASEZ Population (high projections) 25OOOo
’
z /’
B 200000 f g
,’
150000 100000 50000 0 1995
2000
2005
2010
2015
2020
2025
2030
1.52 (2002) 27-39
supply, at present, Wadi Yutum cannot be considered a dependable water resource. Thus, it may be concluded that the gap in water supply will start as early as 2005 and will reach up to 25 MCM/y in 2025 without unconventional water resource. Therefore from above mentioned figures it is evident that desalination of seawater and brackish water is an immanent solution for the provision of extra water supply for the ASEZ to support the growth in investments and population.
Year
Fig. 2. Low/high population projections for the Aqaba special economic zone (ASEZ).
With an average overall per-capita-consumption of 500 l/c/d, the total forecasted low projection water demand for all sectors in the ASEZ amounts to about 40 MCM/y in 2025. Recent studies [7,8] also forecasted a high projection water demand scenario of 78 MCM/y by 2025. Fig. 3 depicts the growth of low and high fresh water demand in the ASEZ. The figure also shows that, if the Wadi Yutum water resource is not utilized, the deficit of water (i.e. demand gap) will arise in years 2005 for the low demand scenario. However, if the Wadi Yutum aquifer is tapped, the demand gap will start around the year 2012 for the low demand scenario. The ASEZA master plan adopts the low demand scenario. Since more detailed studies are required to confirm the reliability of Wadi Yutum aquifer for the water 90 , s
60
s
70
% B m
s
-a- Low Projection s
60
+
%
High Projection
+-Resources
_
.~.
I-
Resources w/o Yutum
5o 40
.a--
w Yutum
.*
5. Recommended
phasing
of a desalination
plant
According to a study by the Ministry of Water and Irrigation [9], it is decided to adopt the reverse osmosis desalination plant on the Red Sea in Aqaba as an option to generate more non-conventional water. It is envisaged that the cost of production of the first 5 MCM/y amount is around $0.7/m3 and the investment cost ofthe first module is expected to be around M$3 5. The desalination plant would be of modular design allowing incremental future expansion to satisfy growing demand. A desalination plant with a capacity of 5 MCM/y should be built in the period between 2005 and 20 10.A future expansion to 10 MCM/y is expected in the subsequent 5 years. Another desalination module of 5 MCM/y would be added to close the demand gap between the period of 20 15-2020 to have a total desalinated water production of 15 MCMy. Starting in 2020, two extra modules of 5 MCM/y capacity each have to be added gradually up to 2025 to have a total capacity desalination production of 25 MCM/y. Fig. 4 illustrates the phases of the proposed desalination capacities and the resulting available water resources superimposed on the low demand scenario.
x
6. Acceptable water standards in ASEZ
0 2000
2005
2010
2015
2020
2025
Year
Fig. 3. Low/high water demand projection and available water resources in ASEZA.
According to the ASEZA Law No. 32 for the year 2000, Article 52 [lo], the standards used in ASEZ shall not go below those standards adopted
S.F: Dweiri, MI. Badran /Desalination 152 (2002) 27-39
1
0 2000
+-Water
7.1. Defining the pollution sources
demand @KM/y)
1 2005
31
2010
2015
2020
2025
Desalination plants whether located near the shore or inland have significant environmental issues that need mitigation unlike the common belief that the brine only is of primary concern. In addition to the proper disposal of the brine, ASEZA has the following significant issues to be considered in any EIA for the desalination plants operated in the zone.
Year
Fig. 4. Total available water resources with desalination and total projected demand for ASEZ.
in the Kingdom. At present, the adopted standards for water uses are identical to those used in the Kingdom. For drinking water standards, the Jordanian Standard JS 286:2001 [l 11provides the physical, chemical, microbiological, and radioactive properties that are acceptable in the zone. Another standard for the use of reclaimed water is Jordanian standard JS 893/2002 [ 121.It provides all acceptable standards for the different uses of the water. ASEZA has established a separate division of standards and codes to develop new standards in the zone.
Environmental impact assessment requirements for desalination plants in ASEZ
7.
Projects to be approved for construction in the ASEZ are required to go through an EIA procedure pursuant to ASEZA Environmental Protection Regulation No. 2 1 for 200 1 [ 131. The procedure is summarized in three parts. The first part is assessing and defining the pollution sources. The second is studying the receiving ecosystem and assessing the assimilative or carrying capacity of the system to abstain damage. The third step is designing and implementing mitigation and monitoring measures to alleviate damage to the environment. The following is a description of these steps.
7.1.I. Construction phase Since the desalination plants require considerable construction on and off shore, it is necessary that direct physical damage be avoided to the aquatic ecosystem, especially to the valuable coral reefs. Construction plans and methods of construction have to be discussed and approved by ASEZA Environmental Commission before commencement of construction and supervised closely by designated staff during construction operation. 7.I .2. Operation phase Subsequent to the construction phase, pollution from the operation phase is of prime concern due to its long-term impacts on the environmental resources in ASEZ. The following will briefly describe these significant issues: Site aesthetics, noise pollution, and land use. ASEZA has developed a master plan in which all land uses are determined. Since desalination plants have detrimental impacts on the site aesthetics and quietude, they are considered as industrial activities and will be located in the southern heavy industrial zone near the shore. Proper disposal of discharge. The concentrate and brine produced by thermal and RO membrane desalination plants are classified as industrial wastes [ 141. Since they do not contain CoZiform bacteria, they are not technically considered municipal wastes. However, the concentrate and brine contain chemicals from the desalination and membrane cleaning processes. Proper measures should be ensured by the plant operators to
32
S.l? Dweiri, MI. Badran /Desalination
guarantee environmentally acceptable disposal of the discharge of brine. Two major types of disposal of concentrate and brine exist. The first is the disposal into sea, and the second is the disposal into land based sites. Disposal of brine and concentrate into sea. Several studies [ 15,161 have identified the groups of components that are considered hazardous to the aquatic life and are discharged from either thermal or reverse osmosis desalination plants. The environmental effects are still not understood for some of these compounds. However, for the purpose of the EIA in the Zone, ASEZA considers these compounds as significant threats to the marine ecosystem until proven otherwise by scientific research. The following are the major types of additives that are discharged with the concentrate into the sea: 1) Corrosion metals. These metals get into the concentrate when the seawater corrodes the metal part of the plant. Thermal plant concentrate includes copper, nickel, iron, chromium, and zinc. These metals will accumulate in the sediment and effect the aquatic life. 2) Anti-scaling additives. Scaling is a common problem in desalination plants. Among the agents that were used to reduce and eliminate scaling is the polyphosphate. This compound will hydrolyze to orthophosphate at a temperature about 90°C. Orthophosphate is a nutrient and will enhance the primary production. As a result, this will induce algal blooms in the area of concentrate discharge. The BELGARD EV2000, a polymer of maleic acid is used instead of the polyphosphate. It is not hazardous in drinking water and is widely approved. Its eco-toxicity is still not proven. Is does not accumulate in algae nor fish. Despite the conclusion that the BELGARD EV is safe, more studies are required to prove this theory in the Gulf of Aqaba. 3) Antifouling additives and halogenated compounds. Chlorine and hypochlorite are commonly used as the main antifouling additive. Usually, they are used at a concentration of 2 mg/l. With
152 (2002) 27-39
good monitoring practices, the concentration of antifouling additives in the discharge is normally controlled at around zero or at a maximum of 0.2 mg/l. Chlorine coverts the naturally occurring bromides to bromine. Chlorine turns into chloride. As a result, the bromine, iodine, chloride, and halogenated compounds concentrations are increased. The risk is augmented when the discharge includes antifoaming additives or oil products. When oil compounds react with chlorine, the result is halogenated hydrocarbons, which are considered carcinogenic. Therefore, responsible monitoring and continuous sampling to control the process of dosing and discharge should be performed to contain the damage. 4) Antifoaming additives. The commonly used chemicals are fatty acids, fatty acid esters and acylated polyglycols. They are used to prevent foaming in thermal desalination plants at typical concentrations of 0.1 mg/l, but this depends on the algal and zooplankton content of the seawater. Overdoses have been detected in many plants. Antifoaming agents have adverse effects on the membrane of the cells. However, the detailed effects on the marine ecosystem in the Red Sea have not been scientifically established. Antifoaming compounds react with halogens. More studies in this area are required. 5) Corrosion inhibitors additives. There are several products that are used for this purpose. No information on this was found in the available literature. However, the advantage of using these additives is the reduction of heavy metals that result from the corrosion of the metal parts of the plant. 6) Oxygen-removing additives. Sodium sulfite is added to remove traces of oxygen, which is a suspect agent in the corrosion process. The sodium sulfite is oxidized into sulfate. Sulfate is considered a normal constituent of seawater. However, the exact biological effects are still not determined. 7) Acid. Acid is added to desalination plants to reduce scaling. Sulfuric acid is commonly used
S.IT Dlveiri, MI. Badran /Desalination 152 (2002) 27-39 for this purpose. Occasionally acid washes uses up to 7000 m of seawater and reduces its pH to 2. This acidic wash when returned to sea causes considerable damage to the marine life. A seawater volume of 25,000 m3 is required to neutralize the acid wash back into the natural seawater pH of around 8. 8) Brine and concentrate. The concentrates generated from thermal desalination plants are about lo-15% more saline that the original seawater salinity. The salinity of the brine is, however, much more for RO desalination plants& is 100-l 30% ofthe salinity of seawater. The marine life can tolerate a maximum increase in salinity of 1 practical salinity unit (psu). Recommended mitigation measures, taken before direct discharge into the sea, are by dilution with cooling seawater, and discharging the brine into deeper water where the salinity is naturally higher. 9) Heat. Thermal desalination plants normally discharge the concentrate with a temperature difference of 15-20°C greater than the natural ambient seawater. Also, dilution is required to reduce the temperature difference to less than 3°C to avoid the bleaching of the corals. However, if the concentrate is discharged into deeper sea, the effect on the marine life maybe less. 7.1.3. Disposal of brine into land In addition to desalination plants that discharge into the sea, another environmental concern is the brackish water RO desalination plants onshore. The proper disposal of the concentrate and brine should carefully be studied [ 143. Common disposal methods include the direct discharge into natural wadis, disposal to sewage treatment plants, deepwell injection disposal, land application as spray irrigation, and discharge into percolation ponds. Since land resources are limited in the ASEZ, and the susceptibility of the underlying groundwater aquifers is high, these methods are not encouraged and not preferable. For on-land brackish water RO desalination plants located near the sea, proper disposal ofthe brine into the sea is recommended.
33
7.1.4, Odor and air pollution Gas emissions are released from desalination plants as a result of energy production necessary for seawater evaporation. Thermal desalination plants vary in the amount of emissions released depending on the energy source used. Energy sources include natural gas, crude oil and diesel oil. Since all types of oils generate sulfur dioxides, hydrocarbon, and non-hydrocarbons, natural gas is the choice for desalination energy in ASEZ. 7.1.5. Solid waste generation Desalination plants produce solid waste that has to be disposed of. It is required that plant operators estimate the volume of solid waste to be dealt with properly. RO plants produce much more solid waste than thermal plants since they dispose of old membranes. The reuse of these membranes has not proven successful yet and thus, the old membranes are considered as waste. 7.2. Assessment of the receiving body ecosystems The second step of the ASEZA EIA procedure for desalination plants is the assessment of the acceptor ecosystem and estimating the carrying capacity (i.e. assimilative capacity) thereof. This requires the study of seawater properties and their interaction with the pollution sources. 7.2.1. Physico-chemical and biological characteristics of the Gulf of Aqaba The Gulf of Aqaba is a semi-enclosed water basin attached to the semi-enclosed Red Sea. It is a morph-tectonic trough originated in late Cenozoic times in the Syrian-African rift system. As a result, the Gulf does not have a coastal plain or a true shelf and its submarine slopes are extremely steep. The length of the Gulf of Aqaba is about 170 km and the average width is about 15 km only. It is totally surrounded by desert; Sinai from the west and the Jordanian Saudi desert from the east. The Gulf is very deep with a maximum
34
SF
Dweiri, M.I. Badran /Desalination
water depth close to that of the Red Sea proper, -1800 m. The climate is arid with high temperature that reaches a maximum during JulyAugust and minima during December-January. The annual range of variation in air temperature is extremely high, about 40°C and typical of the desert climate, the diurnal range of air temperature is also high, 10-l 5OC. Mean annual rainfall is 35 mm/y. All rainfall occurs during the period October-May and 6 1% of the total occurs during December-February. The Gulf receives no river runoff. Several authors have studied seawater characteristics of the Gulf. Basic seawater characteristics are shown in Figs. 5-8. Recent studies [17,18] have shown that waters of the Gulf of Aqaba are typical oligotrophic oceanic waters and that the coastal Jordanian water is only at some restricted sites acutely modified as compared to the offshore water. Coastal as well as offshore waters of the Gulf of Aqaba exhibit a well-defined annual cycle where the water is well mixed during winter and thermally stratified in summer. Winter mixing is a companied with relatively high nutrient and chlorophyll a concentrations, while in summer the concentrations go very close to the detection limit. Salinity is relatively high as compared to average ocean water and exhibits only minor variations both with time and depth. Alkalinity and pH also show little variations, reflecting well buffered conditions capable of resisting acute anthropogenic inputs. Dissolved oxygen exhibits typical saturation concentration and varies basically in association with seawater temperature, which indicates low concentrations of organic matter and consequently low chemical and biochemical oxygen demand. 7.2.3. Suitability desalination
of Aqaba seawater for
The question of suitability of Aqaba seawater for desalination is two fold; the water as an input for the desalination plant and as recipient of the side product brine and the associated material.
152 (2002) 27-39
As desalination plants input, waters of the Gulf ofAqaba has relatively high salinity, which requires more energy and increases the desalination cost. On the other hand the Jordanian coastal waters of the Gulf ofAqaba are of high purity and extremely low pollution content. This counterbalances the high salinity in terms of desalination cost. In some other costal waters the cost of pretreatment to get red of pollutants before desalination can be quite substantial. As a recipient of the desalination side products, the Gulf of Aqaba has several favorable characteristics. It is to be kept in minds however, that ASEZA adopts zero discharge policy. Yet when things come to reality, if it is proven that discharging of the desalination side products into the sea is more feasible than inland, this option shall be considered. Among the characteristics that help the Gulf of Aqaba to accommodate the desalination residues is its great depth that gives a big dilution power, which sequesters the discharge effects. Some other positive factors are the stable pH and alkalinity of waters of the Gulf of Aqaba that provide a strong buffer effect, and the low nutrient, chlorophyll a and organic carbon content that keep the system tolerant to eutrophication. 7.3. Mitigation measures and monitoring plan As a last but most important step in the EIA process, it is required from the desalination plants operators to provide mitigation measures for every component that impacts the environment and to demonstrate how these will lessen the damage to the environment. Post-audits and ecosystem pollution monitoring plans are necessary to be conducted both by ASEZA staff and plant operators. Records of the monitoring are required to be provided to ASEZA as agreed upon in the EIA report. This will ensure proper control of pollution and will detect and contain damage in case on spillage. Moreover, emergency plans have to also be provided and coordinated with the civil dense and public security to ensure safety in and around the plants.
SE
Jan
OJan 29.0 s
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Dweiri, M.I. Badran /Desalination
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152 (2002) 27-39
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u
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Jan
q Feb
*Mar
I* Apr
n May
m Jun
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BSep
q Oct
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Fig.5. Thermohaline structure of the Jordanian coastal waters of the Gulf of Aqaba, Red Sea during the period JanuaryDecember 2000.
36
S.F Dweiri, MI. Badran / Desalination 152 (2002) 27-39 8.48 8.45 8.43 2, b
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6Feb
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Fig. 6. Record of pH, alkalinity, dissolved oxygen and chlorophyll a in the Jordanian coastal waters of the Gulf of Aqaba, Red Sea during the period January-December 2000.
SE Dweiri, M.I. Badran / Desalination 152 (2002) 27-39
37
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Fig. 7. Record of ammonia, nitrate and nitrite in the Jordanian coastal waters of the Gulf ofAqaba, Red Sea during the period January-December 2000.
S. F: Dweiri, M.1. Badran / Desalination 152 (2002) 27-39
38
K3Jan
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DJan
rFeb
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Fig. 8. Record of phosphate, silicate and chlorophyll a in the Jordanian coastal waters of the Gulf of Aqaba, Red Sea during the period January-December 2000.
S.F Dweiri, M.I. Badran /Desalination 152 (2002) 27-39
References The Aqaba Technical Assistance Support Project, Strategic Environmental Assessment, US Agency for International Development, Supporting the Development of the Aqaba Special Economic Zone (ASEZ), Contract No. PCE-I-00-98-00017-00, May 2001. PI Aqaba, Jordan Special Economic Zone Master Plan, 1, 2000. [31 Geohyten Corporation, Aqaba Groundwater Assessment Study, Final Report, Gulf of Aqaba Environmental Action Plan, February 2001. 141 Jordan Department of Statistics public records, September 2001. PI Wilbur Smith Associates, Moffat and Nichol, Gensler, and Consolidated Consultants, Aqaba, United States Agency for International Development, Aqaba Special Economic Zone Authority Jordan Special Economic Zone Master Plan, 3, Port-Land TransportationUtilities, March 2001. 161 The Services Group, Inc, Aqaba FreeporVSpecial Economic Zone, Feasibility Study and Implementation Plan, Final Report, 4: Land Use Master Plan, May 1999. 171 Montgomery Watson, Technical and Economic Feasibility Study and Final Design of the Upgrading and Expansion of the Water and Wastewater Facilities at Aqaba, Environmental Assessment, Final Report, II, September 2000. P31 Acquedotto Pugliese Mediterraneo S. p.A., Project Feasibility Study for the Integrated Utilization of Aqaba Area Water Resources, Preliminary Report, July 2000.
PI
[9]
39
Ministry of Water and Irrigation, Desalination Study for Aqaba, Freeport and Special Economic Zone, draft, 1998. [lo] Aqaba Special Economic Zone Law No. 32 for the year 2000. Vll Jordanian Institute for Standards and Metrology, Jordanian Standard JS 286:2001 Water - Drinking Water, 4th ed., 2001. ITI Jordanian Institute for Standards and Metrology, Jordanian Standard JS 893/2002 Reclaimed Wastewater, 2002. 1131 ASEZA Environmental Protection RegulationNo. 21 for the Year 2001, Issued according to Article 52 and 56 of the Aqaba Special Economic Zone Law No. 32 for the year 2000. Promoting the Benefits of 1141 M. Mickley,Water, Membrane Produced Drinking Colorado, [year?] USI Th. Hoepner, Desalination, A procedure for Environ1mental Impact Assessments (EIA) for Seawater Desalination Plants, University of Oldenburg, Germany, November 1999. [161 Th. Hopner and J. Windelberg, Elements of Environmental Impact Studies on Coastal Desalination Plants, University of Oldenburg, Germany, July 1991. v71 M.I. Badran and P. Foster, Environmental quality of the Jordanian coastal waters of the Gulf of Aqaba, Red Sea, Aquatic Ecosystem Health and Management, 1 (1998) 83-97. [I81 MI. Badran, Dissolved oxygen, chlorophyll a and nutrient seasonal cycles in waters of the Gulf ofAqaba, Red Sea Aquatic Ecosystem Health and Management, 4 (2001) 139-150.
Desalination 152 (2002) 27-39 www.elsevietcom/locate/desal
Desalination: an imminent solution for the future water needs in the Aqaba Special Economic Zone (ASEZ) Samir F. Dweiri”*, Mohammad I. Badranb* 0Environmental Commission, Aqaba Special Economic Zone Authority, Jordan Tel. +962 (3) 2091000; Fax +962 (3) 2014204; email: [email protected] hA4arine Science Station, University of JoraWXarmouk Universily, Aqaba, Jordan Tel. +962 (3) 2015144; Fax +962 (3) 2OI3674; email: [email protected]
Received 25 April 2002; accepted 3 May 2002
Abstract
Jordan has recently given distinguished attention to its single and extremely limited sea outlet - Aqaba. An innovative governing system is being established. Aqaba has been declared as a Special Economic Zone Authority. The main objectives of the new authority are to develop Aqaba as a haven for commerce, a destination for tourism, and an incubator for technology. A strong limiting factor to this ambitious planning is the scarcity of fresh water. The conventional water resources utilized to satisfy the increasing water demand will reach the maximum sustainable yield in less than 5 years. At present, water supply is abstracted from groundwater aquifers and amounts to about 16.4 million m3/y (MCM/y). According to the final master plan of the ASEZA, the total consumption is expected to increase by about 5 MCM/y in the first 5 years, 11 MCM/ y in the following 5 years, and about 30 MCM/y by the end of 20 years. The ultimate allocation for ASEZA from the conventional water recourses from the Disi non-renewable aquifer does not exceed 17.5 MCM/y. This identified gap in water supply has defmitely to be filled by unconventional water resources such as desalination of seawater and brackish water. The location of ASEZ alongside the Red Sea and over partly brackish aquifers does qualie it for desalination. However, the ASEZA Environmental Commission is currently identifying significant issues to be considered in the mitigation measures when designing desalination plants in order to alleviate adverse environmental impacts to the ecosystem. This paper discusses the expected future water demands, the ASEZA acceptable water standards for the different water uses, and the environmental impact of the desalination plants and their respective mitigation measures. Keywords:
Demand and population forecast; ASEZA water needs; Environmental impact assessment; Groundwater resources; Marine life; Desalination; Mitigation measures
*Corresponding author. Presented at the EuroMed 2002 conference on Desalination Strategies in South Mediterranean Countries: Cooperation between Mediterranean Countries of Europe and the Southern Rim ofthe Mediterranean. Sponsored by the European Desalination Society and Alexandria University Desalination Studies and Technology Center, Sharm El Sheikh, Egypt, May 4-6, 2002. 001 l-9164/02/$-
See front matter 0 2002 Elsevier Science B.V. All rights reserved
PII: SOOll-9164(02)01045-7
28
S.F Dweiri. MI. Badran /Desalination
I52 (2002) 27-39
1. Introduction
2.50 Tourist
With the launch of the Aqaba Special Economic Zone in May 17, 2001 and the international inauguration, Aqaba will experience an increase in population and consequently in water demand. The zone was declared as a haven for commerce, tourism and technology. This will result in an expected rise in water consumption for tourism,
industry as well as the domestic purposes. ASEZA is currently working on estimating the water resources and needs in the zone to better predict the water consumption and provide water for all the different uses in an environmentally sustainable way. At present the population of the zone is around 75,000. The current water consumption (year 2001) amounted to 11.2 MCM and is distributed between residential, industrial, commercial, tourist and agricultural as 35.3,35.2,7,2.5 and 20% respectively. Fig. 1 illustrates this distibution. Table 1 shows the year 2001 water consumption and the distribution for the water consumption in ASEZ. According to the Ministry of Water and Irrigation policy, any future supply exceeding the capacity of the Disi pipeline will be ensured from sources other than the Disi aquifer. It suggests the use of non-conventional water like desalination of seawater and brackish water [ 11.
Table 1 Water consumption and total produced water
Water use
Total Supplied water Produced water (all aquifers)
Residential
Fig. 1. Percentage of water consumption distribution ASEZ in 200 1,
in
2. Constraints on natural water resources In the Aqaba zone, the only water resource comes from the groundwater. Four main distinctive aquifers are identified. They are the Disi, Wadi Yutum, Wadi Araba, and Dirreh aquifers. The Disi aquifer is considered a non-renewable aquifer, while the others are renewable. According to several studies on the water resources in Aqaba, there is a virtual consensus that, with the exception of the Disi and the Yutum aquifers, the groundwater is mostly brackish or contaminated and cannot be used for municipal purposes without
in the Aqaba Special Economic Zone (MCM/y) in 2001
Consumption, MCM Quantity, MCM
Industrial Residential Commercial and services Agricultural Tourist
35.29
Total, %
% of supplied water % of produced water
3.95 3.96 0.79 2.25 0.28
35.18 35.29 6.99 20.04 2.50
27.70 27.79 5.50 15.78 1.97
23.97 24.04 4.76 13.65 1.70
11.23 14.26 16.48
100.00
78.74 100.00
68.13 86.53 100.00
29
S.E Dweiri. M. I. Badran / Desalination 152 (2002) 27-39
the supplied water and 32% of the total produced water. The unaccounted-for water includes the water theft, metering errors, and leakage from the pipes. The illegal use and water theft will be considered, for the purpose of this paper, part of the demand. Therefore, the recovery of the unaccounted-for water will not be regarded as an extra resource in the future, especially, since more studies are required to determine the actual physical leakages from the system.
treatment. According to the Ministry of Water and Irrigation, the maximum [2] allocation from the Disi aquifer to Aqaba shall not exceed the maximum capacity of the existing pipeline of 17.5 MCM/y. A recent World Bank study [3], has declared the groundwater safe yields as 5.5 MCMly for Wadi Yutum, 8.5 MCMly for Wadi Araba aquifer and 3.5 MCM/y for Dirreh Aquifer, of which only the waters of Wadi Yutum can be considered fresh water. In 200 1, the abstraction from all aquifers was about 16.5 MCM, of which 13.6 MCM was abstraction from the Disi aquifer. The maximum fresh water resource available for Aqaba amounts to about 23 MCMIy. About 9.5 MCM remains to be utilized from the Disi and the Yutum aquifers in the future. However, without the development of Wadi Yutum aquifer, the unutilizable water resources amount is 4 MCM/y.
4. Population, water demands and future forecasts and gaps In 1994, a complete census was conducted in Aqaba by the Jordan Department of Statistics in which the population was counted as 79,839 people [4]. Using a growth rate of 2.8%, the forecasted population was calculated as 85,080 for the ASEZ area in 2000. The latest population projections of the ASEZA Master Plan and other projections [5,6] are shown in Table 2. Fig. 2 illustrates the low and high population forecasts for ASEZ.
3. Water supply and unaccounted-for water In year 2001, about 14.2 MCM was supplied to consumers from the total fresh water production of 16.5 MCM. Of this quantity, 5.3 MCM is unaccounted-for water, which constitutes 37% of
Table 2 Aqaba special economic zone ASEZ projected population and projected water demand Year
2000
2005
2010
2015
2020
2025
ASEZ population (low projections) ASEZ population (high projections) Consumption per capita (I/c/p) (low projection) Consumption per capita (l/c/p) (high projection) Water demand (low projection), MCM/y Water demand (high projection), MCM/y Available water resource with Yutum, MCMly Available water resource without Yutum, MCM/y Water demand gap, MCM/y Desalination capacity Total available water resource with desalination, MCMfy
74,365 79,33 1 501
113,369 115,608 428
132,808 165,524 431
149,579 235,679 484
172,244 300,000 520
186,468 325,000 582
470
758
760
697
648
658
13.6 13.6 23
17.7 32 23
20.9 45.9 23
26.4 60 23
32.7 71 23
39.6 78 23
17.5
17.5
17.5
17.5
17.5
17.5
0 0
0.2 2 19.5
3.4 5 22.5
8.9 10 27.5
15.2 20 37.5
22.1 25 42.5
17.5
30
S.F Dweiri, ML Badran /Desalination 350000
-+ ASEZ
f
Population (low pmjections)
300000 “I ASEZ Population (high projections) 25OOOo
’
z /’
B 200000 f g
,’
150000 100000 50000 0 1995
2000
2005
2010
2015
2020
2025
2030
1.52 (2002) 27-39
supply, at present, Wadi Yutum cannot be considered a dependable water resource. Thus, it may be concluded that the gap in water supply will start as early as 2005 and will reach up to 25 MCM/y in 2025 without unconventional water resource. Therefore from above mentioned figures it is evident that desalination of seawater and brackish water is an immanent solution for the provision of extra water supply for the ASEZ to support the growth in investments and population.
Year
Fig. 2. Low/high population projections for the Aqaba special economic zone (ASEZ).
With an average overall per-capita-consumption of 500 l/c/d, the total forecasted low projection water demand for all sectors in the ASEZ amounts to about 40 MCM/y in 2025. Recent studies [7,8] also forecasted a high projection water demand scenario of 78 MCM/y by 2025. Fig. 3 depicts the growth of low and high fresh water demand in the ASEZ. The figure also shows that, if the Wadi Yutum water resource is not utilized, the deficit of water (i.e. demand gap) will arise in years 2005 for the low demand scenario. However, if the Wadi Yutum aquifer is tapped, the demand gap will start around the year 2012 for the low demand scenario. The ASEZA master plan adopts the low demand scenario. Since more detailed studies are required to confirm the reliability of Wadi Yutum aquifer for the water 90 , s
60
s
70
% B m
s
-a- Low Projection s
60
+
%
High Projection
+-Resources
_
.~.
I-
Resources w/o Yutum
5o 40
.a--
w Yutum
.*
5. Recommended
phasing
of a desalination
plant
According to a study by the Ministry of Water and Irrigation [9], it is decided to adopt the reverse osmosis desalination plant on the Red Sea in Aqaba as an option to generate more non-conventional water. It is envisaged that the cost of production of the first 5 MCM/y amount is around $0.7/m3 and the investment cost ofthe first module is expected to be around M$3 5. The desalination plant would be of modular design allowing incremental future expansion to satisfy growing demand. A desalination plant with a capacity of 5 MCM/y should be built in the period between 2005 and 20 10.A future expansion to 10 MCM/y is expected in the subsequent 5 years. Another desalination module of 5 MCM/y would be added to close the demand gap between the period of 20 15-2020 to have a total desalinated water production of 15 MCMy. Starting in 2020, two extra modules of 5 MCM/y capacity each have to be added gradually up to 2025 to have a total capacity desalination production of 25 MCM/y. Fig. 4 illustrates the phases of the proposed desalination capacities and the resulting available water resources superimposed on the low demand scenario.
x
6. Acceptable water standards in ASEZ
0 2000
2005
2010
2015
2020
2025
Year
Fig. 3. Low/high water demand projection and available water resources in ASEZA.
According to the ASEZA Law No. 32 for the year 2000, Article 52 [lo], the standards used in ASEZ shall not go below those standards adopted
S.F: Dweiri, MI. Badran /Desalination 152 (2002) 27-39
1
0 2000
+-Water
7.1. Defining the pollution sources
demand @KM/y)
1 2005
31
2010
2015
2020
2025
Desalination plants whether located near the shore or inland have significant environmental issues that need mitigation unlike the common belief that the brine only is of primary concern. In addition to the proper disposal of the brine, ASEZA has the following significant issues to be considered in any EIA for the desalination plants operated in the zone.
Year
Fig. 4. Total available water resources with desalination and total projected demand for ASEZ.
in the Kingdom. At present, the adopted standards for water uses are identical to those used in the Kingdom. For drinking water standards, the Jordanian Standard JS 286:2001 [l 11provides the physical, chemical, microbiological, and radioactive properties that are acceptable in the zone. Another standard for the use of reclaimed water is Jordanian standard JS 893/2002 [ 121.It provides all acceptable standards for the different uses of the water. ASEZA has established a separate division of standards and codes to develop new standards in the zone.
Environmental impact assessment requirements for desalination plants in ASEZ
7.
Projects to be approved for construction in the ASEZ are required to go through an EIA procedure pursuant to ASEZA Environmental Protection Regulation No. 2 1 for 200 1 [ 131. The procedure is summarized in three parts. The first part is assessing and defining the pollution sources. The second is studying the receiving ecosystem and assessing the assimilative or carrying capacity of the system to abstain damage. The third step is designing and implementing mitigation and monitoring measures to alleviate damage to the environment. The following is a description of these steps.
7.1.I. Construction phase Since the desalination plants require considerable construction on and off shore, it is necessary that direct physical damage be avoided to the aquatic ecosystem, especially to the valuable coral reefs. Construction plans and methods of construction have to be discussed and approved by ASEZA Environmental Commission before commencement of construction and supervised closely by designated staff during construction operation. 7.I .2. Operation phase Subsequent to the construction phase, pollution from the operation phase is of prime concern due to its long-term impacts on the environmental resources in ASEZ. The following will briefly describe these significant issues: Site aesthetics, noise pollution, and land use. ASEZA has developed a master plan in which all land uses are determined. Since desalination plants have detrimental impacts on the site aesthetics and quietude, they are considered as industrial activities and will be located in the southern heavy industrial zone near the shore. Proper disposal of discharge. The concentrate and brine produced by thermal and RO membrane desalination plants are classified as industrial wastes [ 141. Since they do not contain CoZiform bacteria, they are not technically considered municipal wastes. However, the concentrate and brine contain chemicals from the desalination and membrane cleaning processes. Proper measures should be ensured by the plant operators to
32
S.l? Dweiri, MI. Badran /Desalination
guarantee environmentally acceptable disposal of the discharge of brine. Two major types of disposal of concentrate and brine exist. The first is the disposal into sea, and the second is the disposal into land based sites. Disposal of brine and concentrate into sea. Several studies [ 15,161 have identified the groups of components that are considered hazardous to the aquatic life and are discharged from either thermal or reverse osmosis desalination plants. The environmental effects are still not understood for some of these compounds. However, for the purpose of the EIA in the Zone, ASEZA considers these compounds as significant threats to the marine ecosystem until proven otherwise by scientific research. The following are the major types of additives that are discharged with the concentrate into the sea: 1) Corrosion metals. These metals get into the concentrate when the seawater corrodes the metal part of the plant. Thermal plant concentrate includes copper, nickel, iron, chromium, and zinc. These metals will accumulate in the sediment and effect the aquatic life. 2) Anti-scaling additives. Scaling is a common problem in desalination plants. Among the agents that were used to reduce and eliminate scaling is the polyphosphate. This compound will hydrolyze to orthophosphate at a temperature about 90°C. Orthophosphate is a nutrient and will enhance the primary production. As a result, this will induce algal blooms in the area of concentrate discharge. The BELGARD EV2000, a polymer of maleic acid is used instead of the polyphosphate. It is not hazardous in drinking water and is widely approved. Its eco-toxicity is still not proven. Is does not accumulate in algae nor fish. Despite the conclusion that the BELGARD EV is safe, more studies are required to prove this theory in the Gulf of Aqaba. 3) Antifouling additives and halogenated compounds. Chlorine and hypochlorite are commonly used as the main antifouling additive. Usually, they are used at a concentration of 2 mg/l. With
152 (2002) 27-39
good monitoring practices, the concentration of antifouling additives in the discharge is normally controlled at around zero or at a maximum of 0.2 mg/l. Chlorine coverts the naturally occurring bromides to bromine. Chlorine turns into chloride. As a result, the bromine, iodine, chloride, and halogenated compounds concentrations are increased. The risk is augmented when the discharge includes antifoaming additives or oil products. When oil compounds react with chlorine, the result is halogenated hydrocarbons, which are considered carcinogenic. Therefore, responsible monitoring and continuous sampling to control the process of dosing and discharge should be performed to contain the damage. 4) Antifoaming additives. The commonly used chemicals are fatty acids, fatty acid esters and acylated polyglycols. They are used to prevent foaming in thermal desalination plants at typical concentrations of 0.1 mg/l, but this depends on the algal and zooplankton content of the seawater. Overdoses have been detected in many plants. Antifoaming agents have adverse effects on the membrane of the cells. However, the detailed effects on the marine ecosystem in the Red Sea have not been scientifically established. Antifoaming compounds react with halogens. More studies in this area are required. 5) Corrosion inhibitors additives. There are several products that are used for this purpose. No information on this was found in the available literature. However, the advantage of using these additives is the reduction of heavy metals that result from the corrosion of the metal parts of the plant. 6) Oxygen-removing additives. Sodium sulfite is added to remove traces of oxygen, which is a suspect agent in the corrosion process. The sodium sulfite is oxidized into sulfate. Sulfate is considered a normal constituent of seawater. However, the exact biological effects are still not determined. 7) Acid. Acid is added to desalination plants to reduce scaling. Sulfuric acid is commonly used
S.IT Dlveiri, MI. Badran /Desalination 152 (2002) 27-39 for this purpose. Occasionally acid washes uses up to 7000 m of seawater and reduces its pH to 2. This acidic wash when returned to sea causes considerable damage to the marine life. A seawater volume of 25,000 m3 is required to neutralize the acid wash back into the natural seawater pH of around 8. 8) Brine and concentrate. The concentrates generated from thermal desalination plants are about lo-15% more saline that the original seawater salinity. The salinity of the brine is, however, much more for RO desalination plants& is 100-l 30% ofthe salinity of seawater. The marine life can tolerate a maximum increase in salinity of 1 practical salinity unit (psu). Recommended mitigation measures, taken before direct discharge into the sea, are by dilution with cooling seawater, and discharging the brine into deeper water where the salinity is naturally higher. 9) Heat. Thermal desalination plants normally discharge the concentrate with a temperature difference of 15-20°C greater than the natural ambient seawater. Also, dilution is required to reduce the temperature difference to less than 3°C to avoid the bleaching of the corals. However, if the concentrate is discharged into deeper sea, the effect on the marine life maybe less. 7.1.3. Disposal of brine into land In addition to desalination plants that discharge into the sea, another environmental concern is the brackish water RO desalination plants onshore. The proper disposal of the concentrate and brine should carefully be studied [ 143. Common disposal methods include the direct discharge into natural wadis, disposal to sewage treatment plants, deepwell injection disposal, land application as spray irrigation, and discharge into percolation ponds. Since land resources are limited in the ASEZ, and the susceptibility of the underlying groundwater aquifers is high, these methods are not encouraged and not preferable. For on-land brackish water RO desalination plants located near the sea, proper disposal ofthe brine into the sea is recommended.
33
7.1.4, Odor and air pollution Gas emissions are released from desalination plants as a result of energy production necessary for seawater evaporation. Thermal desalination plants vary in the amount of emissions released depending on the energy source used. Energy sources include natural gas, crude oil and diesel oil. Since all types of oils generate sulfur dioxides, hydrocarbon, and non-hydrocarbons, natural gas is the choice for desalination energy in ASEZ. 7.1.5. Solid waste generation Desalination plants produce solid waste that has to be disposed of. It is required that plant operators estimate the volume of solid waste to be dealt with properly. RO plants produce much more solid waste than thermal plants since they dispose of old membranes. The reuse of these membranes has not proven successful yet and thus, the old membranes are considered as waste. 7.2. Assessment of the receiving body ecosystems The second step of the ASEZA EIA procedure for desalination plants is the assessment of the acceptor ecosystem and estimating the carrying capacity (i.e. assimilative capacity) thereof. This requires the study of seawater properties and their interaction with the pollution sources. 7.2.1. Physico-chemical and biological characteristics of the Gulf of Aqaba The Gulf of Aqaba is a semi-enclosed water basin attached to the semi-enclosed Red Sea. It is a morph-tectonic trough originated in late Cenozoic times in the Syrian-African rift system. As a result, the Gulf does not have a coastal plain or a true shelf and its submarine slopes are extremely steep. The length of the Gulf of Aqaba is about 170 km and the average width is about 15 km only. It is totally surrounded by desert; Sinai from the west and the Jordanian Saudi desert from the east. The Gulf is very deep with a maximum
34
SF
Dweiri, M.I. Badran /Desalination
water depth close to that of the Red Sea proper, -1800 m. The climate is arid with high temperature that reaches a maximum during JulyAugust and minima during December-January. The annual range of variation in air temperature is extremely high, about 40°C and typical of the desert climate, the diurnal range of air temperature is also high, 10-l 5OC. Mean annual rainfall is 35 mm/y. All rainfall occurs during the period October-May and 6 1% of the total occurs during December-February. The Gulf receives no river runoff. Several authors have studied seawater characteristics of the Gulf. Basic seawater characteristics are shown in Figs. 5-8. Recent studies [17,18] have shown that waters of the Gulf of Aqaba are typical oligotrophic oceanic waters and that the coastal Jordanian water is only at some restricted sites acutely modified as compared to the offshore water. Coastal as well as offshore waters of the Gulf of Aqaba exhibit a well-defined annual cycle where the water is well mixed during winter and thermally stratified in summer. Winter mixing is a companied with relatively high nutrient and chlorophyll a concentrations, while in summer the concentrations go very close to the detection limit. Salinity is relatively high as compared to average ocean water and exhibits only minor variations both with time and depth. Alkalinity and pH also show little variations, reflecting well buffered conditions capable of resisting acute anthropogenic inputs. Dissolved oxygen exhibits typical saturation concentration and varies basically in association with seawater temperature, which indicates low concentrations of organic matter and consequently low chemical and biochemical oxygen demand. 7.2.3. Suitability desalination
of Aqaba seawater for
The question of suitability of Aqaba seawater for desalination is two fold; the water as an input for the desalination plant and as recipient of the side product brine and the associated material.
152 (2002) 27-39
As desalination plants input, waters of the Gulf ofAqaba has relatively high salinity, which requires more energy and increases the desalination cost. On the other hand the Jordanian coastal waters of the Gulf ofAqaba are of high purity and extremely low pollution content. This counterbalances the high salinity in terms of desalination cost. In some other costal waters the cost of pretreatment to get red of pollutants before desalination can be quite substantial. As a recipient of the desalination side products, the Gulf of Aqaba has several favorable characteristics. It is to be kept in minds however, that ASEZA adopts zero discharge policy. Yet when things come to reality, if it is proven that discharging of the desalination side products into the sea is more feasible than inland, this option shall be considered. Among the characteristics that help the Gulf of Aqaba to accommodate the desalination residues is its great depth that gives a big dilution power, which sequesters the discharge effects. Some other positive factors are the stable pH and alkalinity of waters of the Gulf of Aqaba that provide a strong buffer effect, and the low nutrient, chlorophyll a and organic carbon content that keep the system tolerant to eutrophication. 7.3. Mitigation measures and monitoring plan As a last but most important step in the EIA process, it is required from the desalination plants operators to provide mitigation measures for every component that impacts the environment and to demonstrate how these will lessen the damage to the environment. Post-audits and ecosystem pollution monitoring plans are necessary to be conducted both by ASEZA staff and plant operators. Records of the monitoring are required to be provided to ASEZA as agreed upon in the EIA report. This will ensure proper control of pollution and will detect and contain damage in case on spillage. Moreover, emergency plans have to also be provided and coordinated with the civil dense and public security to ensure safety in and around the plants.
SE
Jan
OJan 29.0 s
28.8
g
28.6
Dweiri, M.I. Badran /Desalination
WFeb -
------
q Mar
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* Apr
#Apr
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n May
0 Jun
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q Jun
152 (2002) 27-39
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t?dJul n Aug
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--~_---_.-
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1
27.4
u
27.2 27.0
Jan
q Feb
*Mar
I* Apr
n May
m Jun
q lJul l Aug
BSep
q Oct
*NW
Fig.5. Thermohaline structure of the Jordanian coastal waters of the Gulf of Aqaba, Red Sea during the period JanuaryDecember 2000.
36
S.F Dweiri, MI. Badran / Desalination 152 (2002) 27-39 8.48 8.45 8.43 2, b
8.40
;; %
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z 1 d
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,8.33 8.30 8.28 8.25
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7.4
Jan
q Feb
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=Mny
SJun
n Jul
OAug
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Jan
ff Feb
EtMar
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=Jun
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l"._l""""__ "_."____.
7.3 : d
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=
6.8
B Q
6.1 6.6 6.5
K!Jan
qHotels
6Feb
qMar
8 Apr
May
n Jun
PJul
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ElOct
Fig. 6. Record of pH, alkalinity, dissolved oxygen and chlorophyll a in the Jordanian coastal waters of the Gulf of Aqaba, Red Sea during the period January-December 2000.
SE Dweiri, M.I. Badran / Desalination 152 (2002) 27-39
37
0.6
0.1 0.0 BJan
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WJun
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0 Dee
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5
0.60 0.45 0.30 0.15 0.00 Jan
l
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n Apr
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ill Apr
@#May
OJun
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n Oct
0 Nov
HDec
Aug
mSep
q Oct
n Nov
q Dec
.3 0.25 E z 0.20 0.15 0.10 0.05 0.00 Jan
Feb
BMar
l
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Fig. 7. Record of ammonia, nitrate and nitrite in the Jordanian coastal waters of the Gulf ofAqaba, Red Sea during the period January-December 2000.
S. F: Dweiri, M.1. Badran / Desalination 152 (2002) 27-39
38
K3Jan
Jan 1.2
n Feb
lllMar
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ElMar
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n
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a May
q May
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n Jul
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q Aug
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r _-._ “I-._-~--.l-._-..~ll. -._-.I .“.-.-.-.” .--.. - ._”.-..._...__” .--.--.“.._”--.--..- “_ ““^...-.--“^.. -11
DJan
rFeb
DMar
rnApr
@May
n Jun
llJul
q Aug
ISep
@Ott
RINOV
l Dec
Fig. 8. Record of phosphate, silicate and chlorophyll a in the Jordanian coastal waters of the Gulf of Aqaba, Red Sea during the period January-December 2000.
S.F Dweiri, M.I. Badran /Desalination 152 (2002) 27-39
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