1. Environmental Impact of Seawater Desalination Plants
Environmental Impact of Seawater Desalination Plants.Case Study in Algeria Kamal Mohammedi MESOteam, M. Bougara University, Boumerdès Algeria
) International Conference for Water Resources and Environmental Management (International Conference Center, April  9 -13, 2013) Geneva, Switzerland

2. Contents The Environnemental Impact of Desalination
Desalination Capacity in EUMENA and the world
Case study in Algeria
Conclusion

3. Two Water Desalination Approaches
Centralised Large Scale Water Production
Significant environmental impact
2. Decentralised Small Scale Water Production
For Small settelments far from the grid:
local environmental impact

4. The MESOteam was involved in FP6 EU projects in Desalination with Renewable Energies
RESYSproDESAL project:
RESYSproDESAL=Renewable Energy SYStems for DESALination
OPEN-GAIN project:
OPEN
GAIN

5. Desalination and environmental impact
NoisDesalination is a high energy consumption process (contributing to GHGs emissions) and a potential threat to the environment by inducing damage to the marine environment. e
Visual
CO2, SOx,NOx
Seawater intake
Brine discharge, chemicals in seawater
Desalination Plant
Energy consumption
Cooling seawater (MSF)

7. Brine Discharge in seawater
Large scale desalination plant construction:
The Mediterranean Dead sea????

8. Desalination brine is different to regular sewage outfalls instead of rising and dispersing, it naturally sinks towards the seabed and flows along deep ocean channels (Because it contains roughly twice the concentration of seawater). This severely restricts the amount of mixing and can result in a ‘hypersaline’ layer of water on the seabed. The major concern is the effect that this may have on marine environment. the "Ecological Assessment of the Effects of Discharge of Seawater Concentrate from the Perth Seawater Desalination Plant on Cockburn Sound", prepared by D.A. Lord & Associates Pty Ltd (2005).

9. CO2 emissions
Global Warming 3

12. EU-MENA area

13. Development of an environmental impact assessment and decision support
system for seawater desalination plants
Lattemann-PhDthesis___.pdf (32.0 MB)
uuid:0a bc85- 48cb-8a c8fa94037
Author:
Lattemann, S.
Promotor:
Amy, G. · Höpner, T.
Type:
Dissertation
Date:
Publisher:
CRC Press/Balkema
Related item:
ISBN:
Keywords:
desalination · reverse osmosis · energy · environment · impact
Rights:
(c) 2010 Lattemann, S.
Seawater desalination is a rapidly growing coastal-based industry. The combined production capacity of all seawater desalination plants worldwide has increased by 30% over the last two years: from 28 million cubic meters per day in 2007—which is the equivalent of the average discharge of the River Seine at Paris—to more than 36 million cubic meters per day in Seawater desalination is an energy-intensive process. It furthermore consumes considerable amounts of natural resources in the form of chemicals and materials, and may have negative effects on the marine environment due to the discharges of concentrate waste waters and residual chemicals into the sea. The growing number of desalination plants worldwide and the increasing size of single facilities emphasizes the need for greener desalination technologies and more sustainable desalination projects. Two complementing approaches are the development and implementation of best available technology (BAT) standards and best practice guidelines for environmental impact assessment (EIA) studies. While BAT is a technology-based approach, which favors state of the art technologies that reduce resource consumption and waste emissions, EIA aims at minimizing impacts at a site- and project-specific level through environmental monitoring, evaluation of impacts, and mitigation where necessary. The dissertation contains a comprehensive evaluation and synthesis of the potential environmental impacts of desalination plants, with emphasis on the marine environment and aspects of energy use, followed by the development of strategies for impact mitigation. A concept for BAT for seawater desalination technologies is proposed, in combination with a methodological approach for the EIA of desalination projects. The scope of the EIA studies are outlined, including environmental monitoring, toxicity and hydrodynamic modeling studies, and the usefulness of multi-criteria analysis as a decision support tool for EIAs is explored and used to compare different intake and pretreatment options for seawater reverse osmosis plants.

14. Desalination Capacity in the Mediterranean sea

15. mainly RO

17. Desalination Processes
Thermal Processes
Membranes Processes
MSF
MED RO ED
MVC

18. Eau de mer dessalée : Une production de 2,2 millions de mètres cubes par jour avant 2014 en Algérie

19. Cap Djenet Power/MSF Plant Performances Analysis
Case Study
Cap Djenet Power/MSF Plant Performances Analysis

21. The MSF desalination plant is located in Cap Djenet, 70 km west of Algiers (Algeria), on the Mediterranean coast. The nominal distilled water production is around 500 m3/day from four small scale MSF desalination plants to supply a 700 MW steam power cycle with distilled water. The plant consists of three subsystems: The MSF plant with 15+3 flashing stages, the power generation section and the pre/post treatment sections.

22. Cap-Djenet Power/Desalination plant is mainly concerned with thermal pollution due to the reject of cooling seawater from steam turbine condensers
Discharging Channel
Seawater
Condenser
Pump
Turbine
Pumping Station
MSF
Demineral.
Steam Generator

23. Simplified MSF plant flow process illustration

24. Reject type
reject Mode
Reject massflowrate
Water Temperature
(°C)
Contin.
Discontin.
Cooling seawater X
m3/h
Process water
500 tonnes/year
Laboratory analysis water
Wastewater -
demineralizing station

25. Cap Djenet MSF Unit Exergy Performances Analysis

26. Exergy Analysis of the MSF Unit
Exergy analysis is a thermodynamic second law based tool that identifies the sources of irreversibilities that lead to available energy destruction.
Energy Balance
entropy Balance

27. Exergy Balance or
Exergy Computation:

28. Exergy computation results:
States
Pressure
(bar)
Temperature
(K)
Massflowrate
(kg/s)
Enthalpy
(kW)
Entropy
(kW/K)
Exergy 1
293
66.38
21.44
3.9
16.59 2
3.19
300,51
66 .38
28.41
25.17 3
14.44
6.18
5.47 4
1,034
299,1
5.78
632.85
2.2
62.73 5
300,3
8.61
934.31
3.76
-53.8 6
300, 3
29.00 7
6.1
-385.6 8
2,83
348,4
69.49
397.57 9
2,61
356
75.4
670.37 10
368 75
93.67 11
361
87.67 12
3,3
634.06
63.95 13
1.8
934.87
-53.20 14
1,013
685.34
2.81
-47.87 15
493.02
1.71
67.17 16
51.94
4224.8
16.77

29. performances Parameters
Exergy Efficiency
Fraction of exergy destruction

30. Exergy Destruction Seawater intake pump 28.21 Recirculation pump 36.59
Brine pump
2.15
distillate pump
2.98
Reheating
176.3
Seawater reject
19.7
distillate
3.22
Brine reject
5.33
Evaporation section
289.97
total Exergy destruction
564.45

31. Exergy Flow Diagram

32. Cap-Djenet Power/MSF Plant Brine Discharge Environnemental Impact

33. Measurement of seawater Temperature, pH, Salinity, conductivity vs time: Samples were collected from three sites:, brine discharge point, the reject channel and the seawater intake of Cap Djinet power/MSF desalination plant. .

34. Brine reject area [Google map]
Numerical Simulation of thermal plumes under ANSYS Fluent Environment :
Brine reject area [Google map]
Create Geometry 2D Computational domain under SolidWorks
Meshing under Gambit

35. Numerical Simulation of the Thermal plume : Temperature distribution at t=442 s , t=925 s, t =1259s
Summer:
Winter:

36. Conclusion
We presented a case study on the environmental impact of Cap Djinet/MSF (Algeria) seawater desalination plant. These impacts are mainly due to brine discharge but also to a lesser degree the chemicals used in the cleaning of various modules, thermal pollution, etc.. We performed the measurement of four parameters (temperature, pH, salinity and conductivity) and numerical simulation to visualize the effects of rejection. Measurements of temperature and pH are compliant Algerian liquid discharges indicated in the legislative knowing that there are no limits imposed on the conductivity and salinity. Global results show no effect while there is a local impact due to the relatively small size of the resort of Cap Djinet (500 m3/day). To visualize the effect of brine discharge in the sea we present the results of CFD simulation.
The exergy analysis results showed that the MSF desalination unit is the key component where most irreversibilities and available energy destruction are occuring (CO2 emissions too).
Acknowledgements

37. Next steps
1- Emergy Analysis
Emergy is the available energy of one kind previously used up directly and indirectly to make a service or a product.
In emergy analysis, all forms of energy contributing to a process are expressed in units of solar energy that would be required to generate all the inputs.
2- Extend this study to Large Capacity Desalination Plants more than m3/day…………..

38. Hamma Water m3/day RO Desalination Plant Algiers (Algeria) and Magtaa Oran (Algeria) m3/day RO Desalination Plant

39. Thanks for your Attention
Kamal Mohammedi, ing.,Ph.D.
Mechanical Engineering Dpt.
MESOteam
Frantz Fanon st.
M. Bougara University, Boumerdès Algeria
Tel
Fax