Title: R
1RD CHALLENGES FOR FURTHER COST REDUCTIONS in
DESALINATION
- Mousa Abu-Arabi and K. Venkat Reddy
- Middle East Desalination Research Center
- MENREC2 Conference
- May 9-11, 2005
- Amman, Jordan
2Desalination production capacity
- Total capacity, by the end of 2003,
- (installed contracted) is 37,750,000 m3/day
- Country wise
- - With 20 Saudi Arabia, 18 USA, 16 UAE
- 6 Kuwait, 4.5 Spain, 2.75 Libya, etc.
- By process
- - 43 RO, 32 MSF, 24 others (MED, VC, ED, EDR)
-
- Feed
- - 66 seawater, 18 brackish water, 7 river
water - 4.5 waste water, 3.25 pure
water, etc. - Use - 74 municipality, 18 industry, 3.5
power, 2
3Presentation organization
- Statistical figures of desalination capacity
world wide - Status of commercial desalination technologies
- History of RD in desalination
- Recent RD efforts in desalination
- RD needs in desalination
- MEDRC efforts in desalination RD
- Conclusions
4Saline Water
Fresh Water
Desalting Device
Energy
Brine
5Desalination Technology Status
- Commercial desalination technologies
- Multistage flash distillation
- Multi effect distillation
- Vapor compression
- Reverse osmosis
- Electrodialysis
6Thermal ProcessesMulti-Stage Flash (MSF)Process
7Multistage Flash Distillation
- It was invented in 1950
- First MSF plant was build in 1957 in Kuwait
- MSF is thermodynamically inefficient process
- MSF is matured and mostly used in the Middle
East - Developments in the technology are
- Design optimization of process and Individual
equipment - Unit size increased from 5 to 16 MGD
- TBT increased from 90 to 112 oC
- Improved materials of construction and
structural aspects -
- Capital cost is US 5 to 6 per installed
gallon/day - Desalinated water cost is US 0.8 to 1.5 per
cubic meter
8Thermal Processes Multi Effect Distillation
(MED)Process
9Multi Effect Distillation
- It is adopted from chemical industry to
desalination in - 1900
- First MED plant was built in 1930 in Saudi
Arabia - MED is thermodynamically efficient process
compared - to MSF
- Developments in the technology are
- Unit size increased from 1 to 5 MGD
- Scaling problems reduced by proper design of
condenser tube - bundle and distribution of evaporating feed
- Now TBT is maintained at 70 oC to reduce
scaling - Capital cost is US 3.5 to 4.5 per installed
gallon/day - Desalinated water cost is US 0.7 to 1.0 per m3
10Thermal Processes Vapor Compression (VC)
Distillation
11Vapor compression
- VC plants were first used in naval vessels
powered by - diesel engines in 1940
- Vapor compression is generally integrated with
MED plants. - They are generally used for small or medium
scale applications -
- Two types of vapor compression
- Thermal vapor compression
- Mechanical vapor compression
- Developments in the technology are
- Unit size increased by 5 times now about 1 MGD
- Energy consumption is reduced it is 8-14 kWh/m3
- Now desalinated water cost is US 0.6 to 1.0
per m3
12Reverse Osmosis
- Reverse osmosis was discovered in 18th
century, but break through - occurred in 1950 with the invention of
cellulose acetate membranes - Large capacity SWRO plant of 15 MGD was built
in Saudi Arabia - in 1994
- Developments in the technology are
- Long life membranes with high recovery and
resistance to fouling - Better membrane module designs
- Devices for energy recovery ? pressure
exchangers - Membrane costs are reduced compared to 10 years
back - Capital cost of SWRO plant is US 3.2 per
installed - gallon/day, US 1.93 for brackish water
- Desalinated water cost is US 0.45 to 0.8 per
m3 for SWRO
13Membrane Processes
- Summary of Progress in SWRO Desalination
14Electrodialysis
- ED membrane was discovered in 1950
- First commercial ED plant was build in 1954
- EDR is developed in 1968
- Developments in the technology are
- Better membranes and module designs
- ED is generally applied for brackish water
desalination - Capital cost is US 2.42 per installed
gallon/day - Desalinated water cost is US 0.3 to 1.0 per
m3 for - brackish water desalination
15History of RD in desalination
- Major RD Programs in desalination were in the
1960s and 70s - this was the period for building desalination
plants - In the 1980s and early 1990s - gradual
developments occurred, - concentrating on
- Problem solving approach
- Up-scaling of plants size
- Re- development of standard designs
- RO development continued
- RD in environmental water issues
- Developments in RD were hindered due to
- Little feedback from plants to manufacturers
- Lack of communication between plant owners,
industry, - consultants, researchers
- Most of the work done is un-coordinated work
16Recent RD efforts in desalination
- The RD work done from 1990s till today
- Up-scaling of plants continued.
-
- More developments in membranes
- More concentration on scaling and fouling
- Developed pressure exchangers in RO
- RD on environmental issues continued
17Recent RD efforts in desalination (Contd)
- Presently, RD efforts are not substantial due
to - All the earlier bottlenecks in conducting RD
are persisting - Academic research institutes have insufficient
budget plus - they lack interest since no breakthrough
inventions are - possible
- Technology suppliers are not able to provide
sufficient budget - due to less profits and high competition.
Limiting their RD to - improve their technology.
- Users/governments are not allocating enough
funds due to - high subsidies and also no proper manpower to
conduct - research.
18 R D Needs
- THERMAL SYSTEMS
- Installation Costs
- MSF is a bulky process Simplifications of MSF
Plants is needed - Energy
- MED has more potential for
- Lowering energy consumption
- Utilization of Waste heat energy
- Use of heat pump
-
- Plant Components
- Evaporator shell design
- Condenser design for large plants
- Optimization of ejector system
- Adaptation of compressors for VC distillers
19 R D Needs
- Scaling and Scaling Control
- Study Transit and asymptotic fouling
resistances - Develop operation and control strategies to
minimize chemical consumption - Develop data bank of fouling constituents at
different desalination Sites -
- Raise heat transfer coefficients
- Re-examine thermal and hydraulic design
- Deaeration and decarbonation of the feed water
to reduce non-condensable - NC gas release, prediction methods
- Operation, control and automation concepts
- Distribution of feed water to stage in MED
- Minimization of thermodynamic losses by
exploring - Stage and orifice design
- Demister design
- Tube bundle design
20R D Needs
- MEMBRANE SYSTEMS
- Develop better membranes and membrane modules
that are - Robustness against pollutants, chemicals,
disinfectants, - temperature variations
- Less susceptible to concentration polarization
and fouling - Not affected by cleaning
- Have higher permeability and less energy demand
- Robustness at higher temperatures for hybrid
system application - RD is needed
- To understand the phenomena that affect the
performance of a membrane - Develop methods for systematic evaluation of
problems - Develop database of local seawater conditions as
required for RO plant - design
21R D Needs
- MEMBRANE SYSTEMS
- Fouling and Pre-treatment
- Understand fouling phenomena and mechanisms,
empirical - models
- Develop new pre-treatment methods membrane
(MF,UF) - Full understanding of pre-treatment methods and
hydrodynamics - effects in the module
- Develop standards for specification of fouling
indices - Develop Fouling data bank, case studies
22 R D Needs
- MEMBRANE SYSTEMS
-
- Membrane desalination plants in the Middle East
- Number of SWRO plants are very less due to
- The large dual purpose plants started off with
thermal systems - Seawater TDS and concentration of organics in
the Arabian Gulf - extremely high
- Some initial failures of RO plants in the region
- Lack of cooperation between membrane producers,
RO plant - manufacturers and plant owners
- Very cheap natural gas energy
- RD is needed to tackle the peculiar scaling
and fouling problems - with the Gulf water
23 R D Needs
- ENERGY ISSUES Energy cost is significant part of
the - operating cost, thus need to look at
other sources to - utilize
- Thermal Energy Sources, Non-Fossil Alternatives
- Gas turbine and diesel engine exhaust gases and
industrial cooling - waters
- Steam generator exhaust gases
- Solar thermal energy
- Waste heat in industrial complexes
- Waste energy from incinerator
- Geothermal energy
- Absorption heat pump integration
- Heat sink integration with ACs and cooling
house systems -
-
24 R D Needs
-
- ENERGY ISSUES
- Process Integration
- Hybrid systems
- Utilization of aquifers
- Alternatives to avoid seasonal peaks
-
- Renewable Energy RD to produce economical
thermal or - electrical energy is needed
- Nuclear Energy RD to use low grade heat source
25MEDRC programs in desalination
- Identifies research requirements
- Facilitates research
- Develops reference materials
- Disseminates research results
- Contributes to capacity building in the region
- Provides country technical assistance
26MEDRC Contributions to desalination RD
- MEDRC sponsored 47 projects
- Number of projects topic wise
- - 19 in membrane area, mostly on scaling and
fouling - - 6 on energy issues
- - 7 on non-traditional processes
- - 4 on environmental issues
- - 3 on thermal processes
- - 2 on hybrid processes
- - 2 on assessment studies
- - 2 on Software packages
- - 1 on intake and out fall
- - 1 on certification programs
- 22 projects are completed and 25 are on-going
completed project - reports are available on the web site as
downloadable files. - Most of the projects have reference materials
and results of the - completed projects are useful to
desalination community
27MEDRC RFP
- MEDR has Annual Public Tender for RD proposals
- Solicit projects on basic and applied research
- Unsolicited project ideas are also considered
- MENA partnership is required in every project
- 50 cost share is essential requirement
- Reference material component is required
28Information For Preparation Of Proposals
- Guidelines for the Preparation of Proposals
- Request for Proposals 2005
- - Essentials of RFP
- - Project Titles A, B and C Type priorities
- - Project Outlines for priority projects
- These documents are available on our web site
- www.medrc.org.on
29Global Rd Funding In Desalination
Compare ? Global RD funding for desalination,
20 millions annually, with ? other
expenditures of civilization One
painting of Van Gogh (30x40 cm) at an auction
65 millions Sponsorship of one yacht
team in the Americans Cup 25 millions
One day of Iraq war ?? ? Investing 1 cent per
m3 of desalinated water for progress in
desalination would contribute 113 millions
annually
30Conclusions
- RD efforts are not considerable due to
non-availability of funds - Presently, there is no scope for newly
breakthrough technology - that will reduce the cost of desalination
drastically - RD should continue on the following areas to
improve the - existing technologies
- Design optimization of processes and their
equipment - Scaling and fouling problems
- Pre-treatment methods
- Membranes and module designs
- Alternative materials of construction