Nour FAWAL, Baghdad OUDDANE, Jalal
HALWANI
Huta Marine Works LTD, Huta Group, 1830
Jeddah 21441. E-mail : nourfawal@hotmail.com
1- introduction
2- Key selection for intake factor
3- Types of intake
4- Our selection
5- Intake installation and case study
6- Conclusion
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Population + industry
new water request
tapping the sea and ocean water for desalination
SWRO : intake + treatment + water discharge. The
most challenging aspect is the INTAKE: technical
strategy, regulatory challenges, & public perception
INTAKE: decision key, general type of intake, our
selection and our case study
Intake designs are site specific; (15-20%) of the
capital cost.
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Sea water intake is the essential process of SWRO
since it conditions other processes. The objective is
to provide reliable and consistent high-quality feed
water.
Improvements in the raw water quality lead to
reduction in the complexity of pretreatment systems
and increasing the operational reliability of
facilities.
1)
2)
3)
4)
5)
6)
7)
8)
Required intake capacity
Regulatory region
Site location types
Technical options as a function of installation
location
Water sources characteristics
Ecology and environment concerns
Economic considerations
Stakeholder Considerations
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Two main families : Surface water intake (open) and
subsurface water intake
In general : open intake for the large plant capacity
Water quality is variable
Recently trend is for the use of the subsurface intake
Subsurface intake is limited for the small plant
location
parameter
Dahab, Egypt
Fuerteventura Island, Spain
Al-Birk, Saudi Arabia
SWCC Al-Jubail test sites
Mediterranean location-spring
Site 1
Site 2
DOC (mg/L)
UV-254 (m−1)
TOC (mg/l)
UV-254 (m−1)
Phytoplancton, cell/L
Dissolved protein (mg/L)
Dissolved carbohydrates (mg/L)
TOC (mg/L)
Bacteria (CFU/mL), 0 h
Bacteria (CFU/mL), 24 h
Bacteria (CFU/mL), 72 h
Total picophyto-plankton (cells/mL)
Synechococcus (cells/mL)
Picoeukaryote (cells/mL)
Nanoeukaryote (cells/mL)
TOC (mg/L)
Polysaccharides (mg/L)
Humic substances + building blocks
(mg/L)
Low-molar mass acids & neutrals
(mg/L)
Low molar mass compounds (mg/L)
TOC (mg/L)
Polysaccharides (mg/L)
Humic substances + building blocks
(mg/L)
Low-molar mass acids & neutrals
(mg/L)
Low molar mass compounds (mg/L)
sea water
well1
1.6
1.4
0.5
0.36
57720
2.73
1.57
2
1800
1.1 × 105
5.6 × 104
1.6 × 103
1.3 × 103
1.1 × 103
1.2 × 102
1.2
0.12
1.2
0.8
0.7
0.55
0
0.75
0.52
1.2-2
1300
3.3×105
4.0×106
1.3×102
1.0×102
1.9×101
1700
0.9
0.01
0.5
0.4
0.25
0.16
0.33
0.9
0.4
0.29
0.6
ND
0.26
0.16
0.22
0.13
0.38
0.3
ADVANTAGE
1.
2.
3.
4.
5.
6.
Suitable for most terrains
and projects
High flow capacity
Relatively easy to build
(save time)
Low cost
Rapid implement solution
Smaller footprint and less
visual impact on the
seashore
DISADVANTAGE
1.
2.
3.
4.
5.
6.
Lower and more variable
feed water quality
Poor water quality
Vulnerable to marine
variation conditions
Requiring costly pretreatment
Higher operational cost
Significant environmental
impact during operation
ADVANTAGE
1.
2.
3.
4.
5.
Water quality improved
Stable water quality for
long term
Reduce cost of
pretreatment & operation
Respect the aquatic life
Less vulnerable
DISADVANTAGE
1.
2.
3.
4.
5.
6.
7.
Limited flow capacity
Higher risk of insufficient
flow capacity
Additional pretreatment
maybe required
Plug of interstitial pore
Slow implement solution in
case of problem
Environmental impact:
groundwater, coastal beauty
and mud
High construction cost
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Our plant capacity is 20.000 m3/d
The cost geology (sandy beach)
Stable cost with low wave activity
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Perfect condition to use the subsurface intake
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Time
Available of pre-treatment facilities
Project duration
Stable sea water
Specific Precautions
Stakeholder decision
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Sea bed of Rabigh beach characteristic
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Available aqua organisms
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No boat or ship movement
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Sea water stable with turbidity around 0.6 NTU
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No permit to be directly near the shoreline: 340 m to
reach the shoreline and 90 m inside the sea
False information : sub-contractor install only15m
in the sea
Decision: start running
EC = 42.840 – 43.356 µS/cm (43.119)
pH = 7.7 – 8.3 (7.88)
SDI = 7.16 – 8.12 (7.5)
Temp. = 28.1 – 35.4 °C (31.9 °C)
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GRP pipe is only 15 m inside the sea
Laying down along the sea ground level
No wet well sump
3 storage tanks (22.000 m3) each
Production rate 2*9600 m3/d
Delivery 6000-8000 m3/d
= 11 working days to stop
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Target : to extend the intake GRP pipe to 90m
7 GRP pipes have been damaged
2 options : stop or continue with the available
New situation: 40m from the shoreline, 3 m water
column above the intake point & 5 m above the sea
ground level
EC = 39.000 – 42.700 µS/cm (41.459)
pH = 7.5 – 8.7 (7.96)
SDI = 5.7 – 7.1 (6.5)
Temp. = 26.8 – 33.8 °C (30.9 °C)
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5 GRP pipes arrived, modification started
New situation: 90m inside the sea; 8-9 m of water
column above the intake point; 14m above the sea
ground level
EC = 38.900 – 41.900 µS/cm (40.502)
pH = 7.6 – 8.9 (8.1)
SDI = 5.0 – 5.9 (5.5)
Temp. = 24.4 – 32.1 °C (29.1 °C)
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Coast guard forced the remove of the intake pipe
Intake pipe removed & replaced
New situation: Water deep around 1m, water quality
deteriorated & high temperature
EC = 41.100 – 53.700 µS/cm (47.687)
pH = 7.5 – 8.9 (8.2)
SDI = 7.7 – 11.7 (10.37)
Temp. = 25.3 – 31.2 °C (28.7 °C)
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Decision taken to create a natural filtration system
Stone and gravel have been used
EC = 42.000 – 47.600 µS/cm (45.286)
pH = 7.5 – 8.1 (7.8)
SDI = 9.1 – 10.8 (10)
Temp. = 20.2 – 29.2 °C (26.2 °C)
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Researches support to have deep water
HUTA is the first dredging company in KSA & have
the needed dredger
One dredger was nearby our location
Decision has been taken to modify the water deep
All the approve and access have been arranged
Target: to dredge an intake area of 20*10m with
12m water deep
The New Manhole
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New situation: 4 m above the sea ground level, 6 m
below the sea level, 2 m away from the shoreline
EC = 41.700 – 48.900 µS/cm (44.979)
pH = 7.7 – 8.4 (8)
SDI = 6 – 10.6 (8.7)
Temp. = 20.1 – 28.3 °C (25.5 °C)
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Addition of gravel and stone
New situation: same previous condition + natural
filter
EC = 39.000 – 44.600 µS/cm (43.164)
pH = 7.1 – 8.5 (8.2)
SDI = 6.5 – 7.7 (7.3)
Temp. = 24.2 – 30.8 °C (27.6 °C)
Situation
of Point
intake
depth
18-25/09 near coast along 0.8 m
with seabed
Far from Cond.
cost
µS/cm
14 m
43119
SDI
pH
T °C
7.5
7.9
32
5-18/10
In the depth sea 3 m
water/6m seabed
40 m
41459
6.5
7.9
31
27/1027/11
In the depth sea 9m
water/12m
seabed
90 m
40502
5.5
8.1
29
5-17/12
Near the coast 0 m
(30 cm from
seabed
2m
47687
10.4
8.2
29
23/12 – Near coast + 0m
10/1
gravel and stone
2m
45286
10
7.8
26
1-24/02
2m
44979
8.7
8
25
2m
43164
7.3
8.2
28
Period
6- Conclusion
Best
working
condition with the
maximum water deep
 Better coordination
must be applied
The open intake
helped the quick
action to modify the
situations during the
shorted possible time.
Near coast
manhole
+ 8m
4/3 – 4/5 Near
coast+manhole+
gravel+stone
8m
THANK YOU