See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/279179081
A RESEARCH PAPER ON DESALINATION IN AUSTRALIA
Conference Paper · November 2013
CITATIONS
READS
0
12,092
1 author:
Alfred Mutai
Jomo Kenyatta University of Agriculture and Technology
8 PUBLICATIONS 1 CITATION
SEE PROFILE
Some of the authors of this publication are also working on these related projects:
Simulation of a hospital queuing system - Case study, Thika Level Five hospital View project
All content following this page was uploaded by Alfred Mutai on 25 June 2015.
The user has requested enhancement of the downloaded file.
A RESEARCH REPORT ON DESALINATION
CASE STUDY
AUSTRALIA
A RESEARCH REPORT
BY
ALFRED KIPCHUMBA MUTAI
Jomo Kenyatta University of Agriculture and Technology
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
2
Abstract
The research report studies desalination in Australia. The needs of Australia for
For safe and reliable water quantities continue to increase following the expected population
expansion by the year 2050. Further, the absence of other sustainable water sources, desalination
remains the best option that can meet domestic, public and industry water demand. It does not only
address the immediate water needs but also plays a significant role in addressing Australia’s longterm issue of water security. Thus the research report studies different literature sources across
government and institutional statistics, journals, books and e-books, and websites for information
regarding the desalination technologies, the impacts associated with those technologies, and
overall cost implications. What is more, the report examines the advantages and disadvantage of
each desalination technology, and the determinant factors for each technology.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
3
Acknowledgment
I acknowledge the great works from my mentors in the field of academia for an inspirational and
mental support that saw me through this research process. I also acknowledge the Jomo Kenyatta
University for continued support as well as materialistic support especially in resources.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
4
Table of Contents
Abstract..........................................................................................................................................................................1
Acknowledgment ...........................................................................................................................................................3
1 Introduction ................................................................................................................................................................5
1.1 Overview of Desalination in Australia (1-2 pages) .............................................................................................5
1. 2 Research Objectives............................................................................................................................................5
1.3 Research Report Outline (1 page) ...................................................................... Error! Bookmark not defined.
Literature Review (6 pages)...........................................................................................................................................6
Research Methodology (4 pages) ................................................................................ Error! Bookmark not defined.
Findings on Desalination Technologies Used (15 pages) ..............................................................................................8
Reverse Osmosis........................................................................................................................................................8
Electrodialysis ...........................................................................................................................................................8
Multi-state Flash Distillation .....................................................................................................................................8
Multiple-effect Distillation ........................................................................................................................................8
Vapour-compression Desalination .............................................................................................................................8
Solar Humidification .................................................................................................................................................8
Membrane Distillation ...............................................................................................................................................8
Advantage and Disadvantage of Desalination Technology (2 pages) ........................................................................8
Discussion and Analysis (15 pages) ..............................................................................................................................9
Brief Comparison of the Desalination Technologies in Australia (1-3) ....................................................................9
Environmental Concerns about Desalination Technologies (3-5) ........................................................................... 11
Factors for Choice of each Desalination Technology (3-5) ..................................................................................... 14
Cost of Desalination (3-5) ....................................................................................................................................... 17
Conclusion and Recommendations (2 pages) .............................................................. Error! Bookmark not defined.
References ................................................................................................................................................................... 20
Appendix ..................................................................................................................... Error! Bookmark not defined.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
5
1 Introduction
1.1 Overview of Desalination in Australia (1-2 pages)
In all over the world, salt water accounts for 94% of the Earth’s water and supports numerous
commercial activities such as transport and fishing. For the past few decades, Australia has met
its water supply demands through the use of water catchments and dams. However, considering
the significant lack of rainfall in 2000-2010 that drained most of Australia’s water reservoirs and
the fact that fresh water is scarce in Australia, desalination technologies have captured a lot of
attention as alternative water sources.
Generally, desalination is considered to be more expensive compared to other existing sources,
yet it is more reliable in meeting the country’s water needs.
Research is underway to device cheap desalination technologies
However, considering the
Biophysical Framework
Potential Desalination Users in Australia
1. 2 Research Objectives
To explore the application of desalination in meeting Australia’s water needs
To evaluate different case studies about Desalination in Australia and their relevance to Australia
water needs.
To explain in details the desalination technologies used in Australia and the determinant factors
for each technology.
To examine cost implication of desalination in Australia.
To discuss some of the main impacts of desalination on the environment and the energy
requirements for different technologies...
To discuss the advantages and disadvantages of desalination in Australia.
To draw recommendations on the appropriate desalination technologies to use in meeting the
water needs in Australia.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
6
Literature Review
Australia is one of the driest continents in the world. Its surface water resources are limited as
compared to other continents. The continent has the lowest runoff and rainfall in proportion to its
area. The amount of precipitation received in Australia is less compared to other continents as
shown in Table xx.
Continent
Amount of Annual Rainfall (mm) Amount of Runoff as % of Rainfall
Australia
420
13
Europe
580
40
Asia
610
36
South America 1350
36
North America 660
40
Africa
24
660
Amount of Rainfall and Proportion of Runoff in the Rainfall across six continents.
The distribution of water in Australia varies from one place to another. The amount of runoff
decreases towards the inland, but the patterns for runoff and rainfall have some similarity. In
order to understand the water demand in Australia, it is worth noting that most of its population,
about 57%, occupies the seven capital cities whereas 41% live in Melbourne and Sydney alone.
The only cities faced with difficulties in meeting their water demands are Perth (W.A.) and
Adelaide (S.A.), if we extrapolate into the future.
Research unfolds that some of the dams that were constructed on water catchment areas and
dams were the primary sources of portable water. In fact, the dams, about 499 in number, totalled
a capacity of about 93.7billion cubic meters. Unfortunately, due to recent significant drop in
water stored in the reservoirs as a result of lack of rainfall, most capital cities have been affected
by water shortage. In February 2007, Warragamba Dam, which is Sydney’s primary reservoir,
experienced a drop of about 33%. Therefore, the requirement to depend on alternative water
source became essential.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
7
Ground water is available throughout Australia, although not all of it can be tapped and research
indicates the limited recourse of the continent’s ground water. Further, its seawater and most of
its groundwater is saline.
Another important thing to consider about Australia’s installed capacity for desalination plants is
that they consist of less than 1 % of the overall world capacity, according to research conducted
by different authors. The largest desalination plant in Australia is the 2 MSF plants located at the
Dampier in W.A. and consist of a total capacity of about 1, 8178 m3/day. These plants are
powered by waste heat from diesel and do not operate at their full capacity. At present, these
plants are not used frequently.
Other desalination plants have had a short life as a result of increasing fuel cost whereas old
plants require a lot of maintenance. Currently, some of the old plants are still in operation and
work alongside the newly installed plants.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
8
Findings on Desalination Technologies Used
http://www.environment.gov.au/system/files/resources/ef2c1cc7-07d8-4ed8-8f79816d36fb959e/files/desalination-summary.pdf
This section describes the different desalination technologies, main theory behind each
technology that is used for desalination in Australia, and explores the technique and equipment
used. The details of each technology discussed herein under the subsequent subtopics.
Reverse Osmosis
Electrodialysis
Multi-state Flash Distillation
Multiple-effect Distillation
Vapour-compression Desalination
Solar Humidification
Membrane Distillation
Advantage and Disadvantage of Desalination Technology (2 pages)
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
9
Discussion and Analysis
Brief Comparison of the Desalination Technologies in Australia (1-3)
Desalination is a process of eliminating dissolved minerals including salt from feed water
resource that are salty e.g. seawater, treated wastewater or brackish water.
In Australia, there are several processes and techniques of desalination put in place. These
include; Membrane processes, distillation and other alternative processes.
There are several advantages of reverse osmosis system of desalination over the other
types. Reverse osmosis is inexpensive, easy in operation and is very quick. The system has very
few components that are readily available. These includes plastics and other non-metal materials.
The Reverse Osmosis plant can handle a range of flow rates from few up to 750,000 L/day. The
plant is also energy efficient, meaning that its energy consumption is very low. Reverse Osmosis
can eliminate other chemicals in the water apart from salts. The system however has several
disadvantages. Initially, the system is very expensive to install and has a very low duration. Due
to its operation, the plant requires high-quality materials for construction of its components.
Therefore for a reverse Osmosis plant to work, it incurs a lot of capital both in construction and
operation.
The plant mandates the need to maintain an extensive spare parts inventory at all times. The high
pressures used in running the equipment mostly results in cases of mechanical failures of the
equipment. Such failures reduce the rate of production as well as the lifetime of the system.
Electrodialysis, on the other hand, involves filtering of water through the membrane.
However, pressure is not used in this system. Instead, water that has undergone pre-treatment is
pumped between electrodialysis cells. Recently, there has been several developments towards the
electrodialysis method. Electrodialysis Reversal have been developed to ensure proper
elimination of scales, slimes and foulants that normally form on the cells.
There are several advantages of using the ED/EDR method of desalination. The system has been
found to result in up to 90% high recovery ratio in a single stage.
The system can treat water with a higher level of suspended solids without the risk of clogging or
development of mechanical damage.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
10
The pre-treatment procedure in ER does not employ the use of many chemicals and therefore
does not need to be much precise.
The energy used in this system has a direct proportionality to salts removed rather than the
volume of water treated.
The EDR has a very high duration period. The life expectancy is approximated to be about seven
to ten years. Thus, this system has a long lasting advantage over the others.
The EDR membranes are designed in such a way that they are not prone to bacterial
attack or silica scaling. However, the scaling can be controlled even when the process is ongoing.
The membranes of the system can also undergo manual cleaning.
ER/EDR can have its operation at pressures that are low to moderate in levels. The
electrodialysis, on the other hand, has several advantages. First being the fact that, the systems
membranes requires a regular cleaning using chemicals that are very expensive as well as
dangerous. The membrane sacks of an ER/EDR system are prone to leaking. Although it might
not be a regular occurrence, it’s very expensive to rectify whenever it occurs.
The system allows for the existence of bacteria; non-ionic substances and residual turbidity thus
results in further contamination rather than purification. The system, therefore, requires further
treatment before meeting certain quality standards.
A large percentage of the world`s desalination process can be said to utilize the
Multistage Flash Distillation principle (MSF). Such process are picking fame in various parts of
the world, and its understanding is picking up rapidly. The most preferred desalination method in
large-scale desalination plants is MFS. The process has been used for large-scale desalination for
close to thirty years now. The MSF plants have several advantages over the other systems.
For MSF systems, the salinity of the feed waters does not have an impact on either its process or
cost. The final product of the desalination process is high-quality water as compared to those
from the other systems. Research shows that the salinity levels of such water that has undergone
MSF could be as low as 10mg/L TDS.
Unlike the ER/EDR systems, MSF system requires very minimal pre-treatment of its feed
water. The operation procedure in this system are easy and doesn’t follow a strict procedure as
such. MSF has a long history of commercial use and is, therefore, one of the reliable systems in
its functionality. MSF has the capability of combining with other processes such has utilized the
heat energy from hydro-generation plants.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
11
However, multi-flash distillation has a high capital cost. Setting up the system requires
availability of experts with enough understanding and technical knowledge of the process. The
process is also a high energy consumer to the requirements of pre-heated feed water. The
requirement for heat has found a solution with time through the use of heat recovery process.
The recovery process of MSF is low, and thus more feed water is necessary for the production of
a similar quantity of product water.
Multi-Effect Distillation (MED) has been found to be the most important large-scale evaporative
process.
Environmental Concerns about Desalination Technologies (3-5)
Desalination process that exists has a close association with environmental pollution. The
effect have been found to vary from little effects to lethal effects in other cases. The level of
pollution of a desalination process depends on its waste products and the disposal procedure of
the waste materials.
Reverse Osmosis plants have a lot of brine concentrate that result from the desalination process.
Most of the plants in the world dispose of such substance into large water bodies like the seas
and the oceans. However, there are other more chemicals contained therein water and such will
have a long term effect in the organism and sea creatures. The Penneshaw plant in Australia, for
example, is located along the coastline to allow disposal of brine concentrated into the ocean
through a piping network. The effect of these deposits has long term effect on sea ecosystems as
well as the nature of the water in the deposit zones. However, reverse osmosis have been
designed to remove other chemical contaminants in water apart from salts. The above scenario
have contributed a lot in ensuring the safety of the water and environment.
Several desalination technologies used in Australia require treatment of the feed water.
Treatment of feed water, on the other hand, requires the use of several chemicals. Such
chemicals used in the desalination process when disposed of poses a lot of danger to the
ecosystem.
The high energy hot water form some of the desalination processes are at times not accorded the
right treatment before disposal. The result is the disposal of hot water into the large ocean and
other water bodies or even through the other water disposal sites. The high temperatures of waste
increase the ambient temperature of the seawater and affects the organisms within the vicinity.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
12
Most organisms in disposal sites such as seas can tolerate little deviations of environmental
temperature from the normal. Some even can withstand some higher temperatures for a short
periods. However, with continuous disposal of hot, waste brine into such an environment, means
that, the organisms will be exposed to higher temperatures for a longer period. The result,
therefore, will be the destruction of the marine life.
Desalination also involves heavy metal corrosion from the regularly used cleaning
chemicals, combined with the brine results a multi-component waste that when disposed of, it
poses a great danger to that particular environment. Brine normally contains low amount of
heavy metals like Copper-nickel alloys. It normally comes from the materials used in making of
the heat exchanger surfaces. In the case where such surfaces have their origin from other
alternative metals such as stainless steel, the reverse osmosis brine will contain traces of heavy
metal elements like Chromium and Molybdenum. Although the heavy metal presence are in
small proportions, such traces have always accumulated and end up affecting the soft bottom
habitats of a disposal site.
Reverse Osmosis results in the release of brine with higher salinity and consequently have a
higher density than seawater. Due to the large-scale disposal of brine into large water bodies, it
will result in a great negative effect to benthic communities.
Distillation plants discharges brine substances that are less dense and therefore tend to
float. When such brine gets discharged into sea or oceans, is causes an interference to
productivity of the pelagic community.
Due to the disposal of high temperature and more saline brine into the seawater, the oxygen
becomes less soluble in seawater. Moreover, existence of elements like sodium in the brine
reduce the oxygen levels in water. Such substances are always referred to as oxygen scavengers,
meaning that the use up the available oxygen. Sodium bisulfite has a regular use in reverse
osmosis as a neutralizing agent. Limited dissolved oxygen is very toxic to marine organism;
therefore, aeration of brine is recommended before discharge as measure to safeguard the aquatic
life.
Most of the desalination feed water has chlorine added to it to prevent biofouling on heat
exchanger. Chlorine that has been known to being one of the strongest oxidizing agents is also an
effective biocide, therefore, existence of residual levels in the discharged brine are extremely
toxic to marine life in the discharge site. Use of chlorine has a close association with the
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
13
formation halogenated organics. These substances have been proved to exist and persist in most
marine environments that have acted as a disposal site for desalination waste. Research has
revealed that such compounds are carcinogenic and therefore have subjected the marine life into
great danger.
The use of antiscalants such as carboxylic rich polymers e.g. polymaleic acid to prevent the
scaling on heat exchanger surfaces od desalination plants has been a big contributor to
environmental hazards. Although the antiscalants have low toxicity, it is projected that
continuous use of these chemicals will accumulate residues that will be toxic and of greater
environmental danger when they reach lethal levels.
Coagulants such as ferric or aluminium chlorides have had a regular use in improving the
filtration of suspended material mostly in the Reverse Osmosis feed water. Filter backwash has
high chances or getting discharged into the discharge sites such as the seas. Although coagulants
have no history of harming the sea organism, it is good to note that the continued accumulation
in the sea beds will eventual cause impacts such as burial of sessile organisms. Thus increased
turbidity in discharge should be taken into consideration to prevent any lethal effects in the
future.
All desalination plants have to undergo a cleaning process after a certain period. Mostly,
cleaning in such plants takes place after an interval of six months. Several cleaning chemicals are
used depending on the desalination system. Reverse osmosis plants, for example, makes use of
alkaline cleaning solutions to help eliminate silt deposits and biofilms. Acids, on the other hand,
has a regular use in such plants in removal of metal oxides and scales. Most of the chemicals
used in the cleaning process of are very hazardous to the aquatic life. However, the cleaning
process involves passing heated water mixed with the chemicals through the plant and finally
discharged into sites like seas or other designated disposal sites. Such chemicals, therefore, end
up in the sea and thus harms the aquatic life. Due to this effect, it is, therefore, recommended
that, treatment of water used in cleaning is essential before discharging into the sea.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
14
Factors for Choice of each Desalination Technology (3-5)
The existing desalination technologies exists in varieties, and each has its benefits and
disadvantages. Each technology best suits a particular need and the available resources.
Therefore, when choosing the most suitable establishment of a desalination plant, several factors
must be put in place.
Determination of performance ratio is crucial before stabling a desalination plant.
Performance ratio refers to the ratio of available fresh water available to the amount of energy
consumed. Therefore depending on the cost of fuel available in the country, determining of the
proper performance ratio becomes easy. Mostly, in countries with low fuel cost, a
low-performance ratio is always recommended while, in countries that have a higher fuel cost, a
high-performance ratio is always recommended. The selection of performance ratio also depends
on the amortisation period of the plant.
The actual cost of putting up a desalination plant varies with the type of plant and the
requirements of the process. The cost of equipment also varies from one manufacturer to another.
Depending on the fresh water requirements from the country, technical specifications of the plant
and the required capacity of the plant equipment can be determined. In cases where larger supply
of fresh water in needed, larger equipment capacity need to be placed to meet the demands. Such
will incur more cost both in construction of the plant and running of the process.
Taxes and interest has a great effect on production of fresh water through desalination
process. Interest rates have an effect on capital cost, performance ratio, total investments and the
actual selection of the most appropriate plant.
The cost of land to put up the plant is a major determinant of the location. The
composition and level of salinity of the feed water determine the appropriate type of the
desalination plant that should be put up. The source of water used in the plant has always acted
as one of the major factors to consider while setting up a desalination plant. The distance
between the feed source and the plant helps determine the appropriate method of disposal of
waste brine. Several method and procedures of waste disposal have had a great development, and
each method has its impacts in the environment. Most desalination plants exist along the shores
of seas for easy disposal of the wastes. However, for some other water logged countries that have
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
15
no large water bodies within their vicinity, they have to explore other options of safe disposal of
the waste brine without the risk of causing environmental degradation. Other methods such as
evaporation and disposal of wastes inform of steam. The wastes can also be disposed of in the
form of salt ponds or impounding underground.
Different types of water source have different impacts, and this has affected the
performance and the operation of the plant. Below is a tabulated summary of the impacts and
problems associated with the different water sources.
Application
Operational problem
Impact on reliability
Seawater (Membranes)
Clogging of intakes or pre-
Decrease in plant production
treatment
capacity
Biological growth on
Increase in energy
membranes and process
requirements.
surfaces.
Possible loss of production.
Negligible impact on quality
Seawater (Thermal)
Groundwater (Membranes)
Precipitation of calcium
Marginal increase in energy.
carbonates and sulphates on
Decrease in product water
membrane surfaces.
quality.
Precipitation of salts and
Loss of energy efficiency and
corrosion of heat exchanger
decrease in equipment life.
surfaces.
No loss of product quality.
Precipitation of salts and
Marginal increase in energy
silica on membrane surfaces.
requirements.
Increase in salt transport
across membranes.
Decrease in water product
quality.
Wastewater (Membranes)
Biological growth on
Increase in water
membranes and process
requirements to drive water
surfaces.
across the membranes.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
16
Possible loss of production
capacity.
Negligible impact on product
quality.
Table 1.0
Energy sources are one major component considered when choosing the appropriate
desalting plant. The level of fluctuation of the fuel prices greatly affect the cost of production of
fresh water. Identification of cheaper energy source for use in production is, therefore, crucial.
The need to carry out pre-treatment differs from one process to another. Pre-treatment increases
the cost of producing fresh water especially with the Reverse Osmosis process.
The availability of chemical use in pre-treatment also determines the cost and method of
desalination that can exist. Such chemicals also affect the maintenance cost of desalted water.
Most desalination plants require technical skills both in operation and set up. The
availability of such skills and prospect place is essential. Several countries still face the problem
of saline water resource due to lack of personnel with enough knowledge and skill that can help
put up such plants. Importing such skills, on the other hand, is very costly as compared to when
it is readily available. The type of disposal, treatment of both waste and feed water needs very
precise measurement and thus adequate knowledge for personnel running the plant is crucial. A
desalination plant has the capability of running efficiently without any trace of negative
environmental impacts given that there are well trained personnel to ensure that all precautions
are in place.
There are several new technologies in the market that have come up as a result of
research work done by scientist and other scholars in the field. New modifications to the current
technologies are currently in place. Such technologies have components that make the new
systems more efficient, more economical and even more environmentally friendly.
The Electrodialysis method, for example, has seen a new modification in market. The
introduction of Electrodialysis Reversal (EDR) has been developed to solve the problem of
development of scales in the pipe surfaces.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
17
The suitability of a desalination technology depends on the availably of the resources and
the cost available for the plant establishment. Below is a summary of the various desalination
technologies and some of their strengths and weakness that can be put into consideration when
choosing the most suitable desalting technology.
Process
Status
Strength
Weakness
Thermal
Major application
Well established
Energy demand
Electrodialysis
Significant for low
Well established
High primary power
salt feeds.
Reverse osmosis
Major application.
demands.
Established.
Energy efficiency is
Low energy demand.
low.
Relative to the
thermal process
Thermal membrane
Developmental
Ambient pressure.
Low grade heat.
Table 1.2 Summary of various types of desalination technologies.
Cost of Desalination
As discussed earlier, the cost of desalination depends majorly on the type and capacity of
the desalination plant. However, several factors other also contribute to the cost of a desalination
plant. All desalting systems require a constant energy supply to facilitate the production of fresh
water from saline seawater. Therefore, the cost of the available energy will affect the cost of a
desalination technology.
Nearly all desalination plants use electrical power as a source of energy. Processes like
EDR and Reverse Osmosis have been designed to use electrical energy as the primary source of
energy. Australian cost of electricity is varying from state to state with an n average cost of
$0.15 per unit Kilowatt-Hour. Distillation process of majorly all desalination processes with the
exception of VC and solar still use thermal energy in the form of steam. However, there are
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
18
several other sources of thermal energy including waste heat steam from existing plant sites e.g.
gas turbines and solid waste incinerators. In Australia, the cost of steam depends on the different
state. However, the cost is averaged to approximately $0.05 per Kilowatt-Hour. For economical
reasons, further energy sources like the renewable sources e.g. solar and wind has been used to
cut on the cost of energy consumption.
The location of the feed water source determines the suitability and viability of a
desalination plant. It also dictates the cost of running the plant given the dimensions needed in
order for the plant to run smoothly. The location of the feed water source has great influence on
the cost of transporting from the source to the plant, cost of power and fuel needed for that
transportation and the general viability of the plant.
The feed water quality has a great impact on the cost of fresh water production. The
quality, total delivery capacity of the source and the ability for extraction at an economically safe
manner is crucial for any feed water source. Regions with adequate groundwater flow systems
can supply comfortably an average amount of feed water to support desalination plant
requirements. Moreover, the quality of feed water will determine the type of desalination system
to be used. For feed water sources with high-quality fluctuations, distillation technologies are
more suitable than membrane based technologies. The key water parameters that determine the
quality of water include salinity, level of turbidity, organic contents as well as the levels of pH.
The need of treatment and pre-treatments of feed water determines the cost of
production of a desalination technology used. Different desalination technologies have different
water treatment and pre-treatment needs and therefore have varying cost of fresh water
production. Distillation base technologies like the Reverse osmosis systems will require less
treatment and pre-treatment needs as compared to the membrane based technologies. Membrane
based technologies however require very rigorous pre-treatment practises making such
technologies more costly.
The type of disposal of the waste brine from the desalination process affects the costs of
that particular desalination technology. Most desalination technologies preferably discharge the
waste brine into the sea or any other large water bodies. Therefore, the proximity of the plant to
such sea determines the cost of production of fresh water from the plant. In cases where the
waste discharge is far from the plant, a lot of costs incurred in facilitating the transfer of wastes
to the designated location. The type of disposal technique used is, therefore, directly related to
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
19
the cost of production. Much preference is given to situations where the large water bodies are
too far from the plant; alternative disposal techniques can be put in place in order to maintain the
productivity of the plant within the economical levels. Use of inappropriate disposal method may
result in unexaggerated cost of production of the plant and may end up jeopardizing the viability
of the plant. Before a desalination, it is recommended that the plant is first set up, the most
appropriate mode of waste brine disposal should be investigated and determined.
The financial and economic analysis of such plants has several mathematical ways of
expression. The standard models of analysis has been used widely. The capital cost and the total
annual operating water cost per unit of process capacity. For construction costs, direct capital
costs including the cost of treatment, purchase of equipment, pumps, pipes and control systems
have been incorporated. Below is a summary table showing the cost of application of
desalination technologies.
Parameter
Seawater RO
Capital cost (A$ 1,600 – 2,500
Brackish RO
MED
EDR
600 – 1,800
2,500 – 3,900
570 – 3,250
0.65 – 1.50
With waste heat:
1.00 – 2.80
per Kl)
Operating cost
1.89 – 2.20
(A$ per K)
0.55 – 0.95
Without waste
heat 1.8 – 2.80
Table 1.2 summarized cost of desalination technologies.
The competitiveness of desalinations is best analysed by comparing its operation cost
with the tariffs charged on the existing traditional forms of supply. Considering the net cost of
both the traditional and the current desalination systems, a fully specified economic analysis of
the technologies could be developed.
A RESEARCH REPORT ON DESALINATION IN AUSTRALIA
References
Coombes and Mitchell (2006) Urban Water Harvesting and Reuse, in Australian Runoff
Quality, Wong (editor), Crows Nest.
DNRM (2003), Desalination in Queensland, Brisbane.
DEFRA (2006) Avoiding Dangerous Climate Change, Report from the Scientific
Symposium on Greenhouse Gases, Exeter, UK.
ESAA (2005) Energy Supply Association of Australia, Energy 2005.
Gallop (2005b) Wind farm chosen to power Perth’s desalination plant, Media Statement
Released 26th July, 2005.
Gallop G. (2005b) Presentation to Australian Water Foundation , Perth.
GPAA (2006) National Green Power Accreditation Program Annual Audit, National Green
Power Steering Group.
Holt (2006) Decision making framework for selecting sustainable wastewater reuse
treatment technologies, First Australian Young Professional Conference, UNSW.
Leslie (2004) Desalination: Its place in meeting our fresh water needs, Presentation to
Institute of Energy Australia, 15 November, 2004.
Llewellyn, P. (2006) “Desalination Plant, Renewable Energy”, Parliamentary Questions to
the Minister for Energy, Western Australia Parliament, 16th August 2005.
MacGill I., Outhred H. and Nolles K (2006) “Some design lessons from market-based GHG
regulation in the restructured Aust. electricity industry,” Energy Policy, 34 (1), pp. 11-25.
MacGill, I., Passey, R., Nolles, K. and Outhred, H. (2005) The NSW Greenhouse Gas
Abatement Scheme: An assessment of the scheme's performance to date, scenarios of
its possible performance to 2012, and their policy implications. Discussion Paper
DP_050408, Centre for Energy and Environmental Markets (CEEM), University of NSW.
Mitchell, G. (2006) Applying Integrated Urban Water Management Concepts: A Review of
Australian Experience, Environmental Management, Vol 37, No 5, pp 589-605.
MRET Review (2003) Renewable Opportunities: A Review of the Operation of the
Renewable Energy (Electricity) Act 2000, Australian Greenhouse Office, Canberra.
NSW Government (2006a) 2006 Metropolitan Water Plan, Sydney.
NSW Gov (2006b) NSW Renewable Energy Target Explanatory Paper, NSW Government.
NSW Legislative Council (2006) A Sustainable Water Supply for Sydney, Sydney.
Passey, R., MacGill, I., Nolles, K. and Outhred, H. (2005) The NSW Greenhouse Gas
Abatement Scheme: An analysis of the NGAC Registry for the 2003 Compliance Period.
View publication stats
20