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Descz~tiation, 39 (1981) 394-&l Elsevier Scientific Publishing Company, Arnskrdam - Printed in The Netherlands
399
DESALINATION IN AUSTRALIA - PAST AND FUTURE
G.G. Fenton and J-P_ Gerofi
Solar Desalination Group, Department of Chemical Engineering
University of Sydney
ABSTRACT
Despite Australia’s vast arid areas, Australia only has a very small proportion
of the world’s installed desalination capacity_ This paper surveys the current
plants, and outlines some of the operational problems that have occurred. Demi n-
eralisation plants are also considered. The water resources of Australia are
reviewed, and areas delineated where desalination might be applicable. Within the
context of the energy sources available in different localities, the potential
applicability of various desalination technologies - distillation, RO, ED and VC -
is discussed.
INTROGUCTION
Australia is the world’s driest continent. The limited extent of its surface
water resources can be seen in Table 1, where rainfall and runoff are compared for
the six continents [ 11. Australia has not only the lowest rainfall and runoff in
proportion to its area, but also the lowest percentage of runoff to rainfall. That
is, even the proportion of water available for use from Australia’s low level of
precipitation is less than in other continents.
TABLE 1 : Rainfall and Runoff of the Continents C 11 Averase annual Runoff as a
Africa North America South America Asia Europe Australia
rainfall* Percentage of (mm) Rainfall
_ 660 660 42:
1,350 610 33: 580 40 420 13
The distribution of surface waters is quite variable across the continent as
shown in figures 1 and 2_ Except for a more marked decline in runoff towards
the inland, the rainfall and runoff patterns are quite similar. The relatively
well watered portions of the continent are the far north, the eastern and south-
eastern seaboard, and the south-western tip S and represent only a small proportion
400 FENMN??ND GSROFI
of the land mass. The bulk of the population is located in these areas. In fact
57% of the nation’s population inhabits 7 capital cities. (414 live in Sydney and
Melbourne alone). Of these capital cities only Adelaide (S.A.) and Perth (W-A3 are
like19 to have difficulty in meeting their water needs in the traditional ways for
the foreseeable future, and the other cities in general have supplies of excellent
quality fairly readily available [ 2,31.
Groundwater occurs throughout Australia, although useful supplies cannot be
tapped everywhere. Major sedimentary basins extend under 60 per cent of the con-
tinent and much of the inland is dependent on these as a source of groundwater for
stock and domestic consumption. Knowledge of Australia’s groundwater resources is
still limited.
Figure 3 shows the salinity of the groundwater where it is known, categorised into
areas with salinities in the ranges of under l,OOOppm, 1,000 - 7.000ppm, 7,000 -
14,000 ppm and greater than 14,000 ppm- In areas where different salinities are
recorded, the highest has been indicated. Aquifers are generally recharged by rain,
although the point of recharge may be a very long way from the point of use. It
should be noted that some areas, such as the southern parts of South and West
Australia, and parts of the N-T., have groundwater of very high salinity - sometimes
considerably more saline than seawater. Their particular composition often render
these waters much more corrosive and prone to scale formation than seawater.
Areas of Australia with ?ow annual rainfall (or runoff) and where either the
available bore water is saline or only seawater is available, represent the regions
where desalination of the local water may be the best means of supplying water.
Figure 4 outlines these regions, and was derived by super-imposing the appropriate
areas of Figures 1, 2, and 3. Regions with groundwater salinities less than 1,000
ppm have been excluded, even though desalination could still be needed in Some
cases. Some coastal regions have both seawater and lower salinity borewater
available. Some of these areas already have desalination facilities in operation.
Water may be needed either as potable water or for industrial and agricultural
use. The World Health Organisation’s recommended maximum potable water Salinity
is 500 ppm but this limit is considerably higher than the present norm in Australia.
Salinities for agricultural purposes can be much higher. depending on the
particular 1 and usage. Industry usually requires very pure water: a notable
example is water as boiler feed. The costs involved in any of the desalination
processes, even for brackish water, generally prohibit their use for agricultural
purposes _ In urban areas of Australia, water costs are generally low by world
standards; with excess water rates ranging around 30 cents per m’. These charges
do not necessarily represent the real cost of supplying water; for instance in
South Australia in 1979 a statewide price of 22 centssjm3 was charged, although
the mean water costs to the Government in the different State districts ranged
between SO.27 and $1.01 per m3.
FENTON AND GEZROFI 401
These costs all include both headworks and reticulation. Even the maximum cost
is below the water production cost from present seawater desalination plants.
However, it should be noted that in many areas of South Australia and Western
Australia existing surface water resources are almost fully utilized and additional
capacity can only be provided at very great capi cost- For example, a major
increase in demand at Fort Augusta could require adding to the capacity of the
pipeline system from the Murray River 3OOkm away - at considerable expense.
Adelaide also draws a large proportion of its water from the Murray River. There
are no other untapped catchments available to Adelaide and it is difficult to see
how any major augmentation to the supply could be arranged.
ENERGY SOURCES IN AUSTRALIA
(a) Electrical Power
Australia has abundant coal reserves, particularly on the Eastern seaboard, and
hence most of the nations electrical power system is coal-based. f&t of the larger
power stations are situated near the coal source , with grid connections to the
major cities. Tasmania, NSW and Victoria also have large hydro-electricity
generation systems. Despite the large distances involved, power costs in regions
serviced by the grid are relatively low with prices as low as 2 cents/kWh available
to large bulk users.
Not all areas of Australia enjoy such low power costs. Western Australia in
particular relies on diesel generators to provide power to over 40 remote towns.
South Australia’s coal reserves are of poor quality, and located in remote regions,
and the FIorthern Territory relies almost exclusively on diesel-based power. For
larger-sized diesel-generation plants, power costs of 10 - 17 cents/kWhe appJy
I 41- In remote regions, costs can be considerably higher.
(b) Thermal Energ&
Australia currently produces 65Z of its oil requirements, the remainder being
imported, however the retail price For fue7 is based on world parity prices.
Australia’s own Fields produce mainly light oils, so the heavier fuel oils are
largely imported. To provide thermal energy. fuel oils compete with natural gas
which is available in the mainland capital cities. In coastal regions fuel based
thermal energy costs about 2.2 centS/kWhth (based on Bunker C fuel oi7) but can
rise to 2.6 cents/kWhth in regions where low sulphur fuel must be used. In
remote regions - particularly towards the arid central parts of Australia - transport
costs increase the effective thermal energy cost even further.
Few remote regions are connected to a power grid system, and so rely on diesel-
generators - Hence in most such regions, waste heat from diesel jacket water and
exhaust gases is available at very low cost, however, little of this is utilized.
Another potential source of thermal energy is solar energy. Figure 5 presents
402 FEWTONANDGEROFI
the annual average insolation within Australia, and shows that most dry remote
regions enjoy a high intensity of solar radiation. Use of solar energy is an
emerging technology, but the cost of thermal energy from such systems is
presently fairly high. A notable exception is that of solar ponds, where - in
sites where they are applicable - thermal energy costs would appear to he lower
than those from fuel-based systems [ 51.
EXISTING DESALINATION PLANTS
Despite its status as the worlds driest continent, current desalination
installations in Australia represent considerably less than 1% of the total world
capacity. Table 2 is a sumnary of current Australian desalination plants; this
is based on data from 151 and also from an extensive survey conducted by the
authors. The table excludes a number of VC and MSF plants installed on Naval and
oil-dril!ing vessels and some very smzll plants. If “desalination” is extended to
cover “demineralisation”; i.e. the production of high purity water from supplies
which are generally potable, then many other large installations - almost all
ion-exchange - can be included. Table 3 is a partial listing of Australian
demineralisation facilities. Figure 6 plots the locations at most of the plants
in Table 2 and 3.
Of the desalination plants, the largest installation is that of the 2 MSF plants
at Dampier, \/.A., with to?;al capacity of 1,817 m3/day. In actual fact, these
plants, powered by diesel waste heat, have not operated at full capacity, and are
at present used only infrequently. All the other MSF plants listed are at Moomba.
S.A., servicing the natural gas processing operation there. High recirculation
rates are used, bringing the average feed salinity to 11,000 - 15,000 ppm. These
plants have been operating continuously, with regular acid cleaning every 4 - 6
weeks.
Some plants included in earlier surveys [7] have had fairly short lives due both
to the rising cost of fuel (older distillation plants were designed for quite low
PR’s) and because of high maintenance costs. An example is the 26 m3/day VC
plant installed at Rottnest Island, W-A., in 1963. The original unit broke down
continuously and had to be replaced by the manufacturer in 1964. ilver the period
1963/70 the total operating cost - excluding capital charges - average $2.09/m3,
however, over 1969/70 the operating cost was !j3.67/m3 : the plant was abandoned
in 1970. Similarly, a 27 m3/day VC plant installed on Heron Island (Queensland)
in 1968 is no longer operational. The VC plants on offshore oil platforms in Bass
Strait have been reported as needing frequent (and costly) maintenance to keep
on-line; with scaling being the main problem.
FEKQN hND GEROFI 403
TABLE 2 : AUSTRALIAN DESALINATION PLANTS
Location Operator Capacity (m3/day) m
Western Aust. Exmouth U.S. Navy 440 Dampi er Hamersley 2x 900
Amber Eucl a Hotel 6.0 RO Raw1 inna A.N. Rly. Barrow Is. UAPET z !oo Dampi er Hamersley 2x160+13 RO
+2 Agnew A. Nickel 66 Dampier C.R.A. Ltd. 0.24 z: Dampier C.R.A. Ltd. 3x 48 RO Madura Hotel Newmount 7 RO Tel fer Gold 68 RO Denham Govt. 75 -+ 75 RO Karratha Govt. Kwi nana State Elect - Perth Q-E-Medical Fremanti e Hospital Useless Loop Shark Bay Salt Lake McLeod Texada Sal t Coral Bay Motel ,C’van
RO 72;
45 :: 5 RO
100 RO 23 RO 3? RO
South Aust. Moomba Santos 228 MSF Moomba II 244.8 MSF Moomba II 547.2 MSF Cook A.N. Rly 20 RO
Port Lincoln Govt.MeatWorks 114 RO Adelaide Fl i nders Med _ CooberPedy Govt. 68.: ::
Port Augusta A.N.R!y ? RO Yal ata Abo.Res. 7 RO CooberPedy Govt- 68.2 RO Manguri A.N.Rly 60.0 RO LeighCreek ETSA 700 RO Moon&a Santos 54T MSF
Vi ctori a Bass Strait Victoria Victoria
27.3 9.1
36.4 vc Victoria 36.4 vc Victoria Vi ctori a 5::: ;: Barracouta- Platform Esso 18.2 t+zlbourne Govt.
1::; ::
Mei bourne R.M.I.T. RO Tuna- Platform Esso 18.2 vc Mackerel - Platform Esso 18.2 vc Snapper- Platform Esso 18.2 vc
Manufacturer
Ioni cs trlei r Uestgarth Havens Intl .
0 Permuti t
II
Clough&Sons Pet-m&it
II II II
Aqua-Chem II II
Paterson Candy
Permuti t ,I
I.B.C.Fluid Systems
1-B-C. I.B.C. Permuti t Aqua-Chem
Feedwater commiss- Salinity(ppm) ioned
1.700 1967i 35,000 1968
16,000 1968 2,500 1969 2.500 1973 1,000 1975+
4,500 1976 1976 1976
13 .ooo 1976 2;ooo 1976 5,000 1977 1 .ooo 1980
750 1980 750 1980 750
5,000 Bore Bore
1980
2 .ooo-4,000 1969 I, 1973 II 1976
9,000 1976
BOO 1976 700 1978
17,200 1980
8,000 Bore
17,200 1981 8,200 1981 5,000 1981
2 .ooo-4,000 1981
35,000
35,000
II 35,000 1975 Permuti t 100 1975
II 26 1976
Aqua-Chem
II Mechanical Equip_(MECO)
35,000
35,000
35,000
1977
1977
1980
1967 1967 1968 1970 1970 1970
404 FENTON AND GE!2OFI
TABLE 2 : Ausm-v_~AN DESALINATION PLANS (CONTINUED) Victoria Flounder- Esso 18.9 RO Koomey Platform Victoria 54.6 vc Aqua-Chem Port Fairy Glaxo 4.5 RO Permutit West. Kingfish Esso 18.2 vc MECO Platform Cobla Platform Esso 18.2 vc MECO Fortescue Platform Esso 18.2 vc MECO Melbourne Esso 65.5 RO 1-B-C.
35,000 1980
1980 900 1980
35,000 1981
35,000 1981
35,000 1981 17,200 1981
New South Wales Sydney Ciba Geigy z-i Pennutit 100 1973 Maitland Aust.Coal Ind. ,I
65 l-4,000 1974
Tarago Woodland Mines II 1,000 1977 Tamworth Hospital 9 II 150 1977
Queensland Barrier Reef 54.6 vc Aqua-Chem 35,000 1970 Oakey Army 46.0 RO Permutit 500 1974 Blackwater Old. Coal 11.0 RO Permutit 2.000 1976 Brisbane 91.0 R" 1-B
II- C. -300 1977
Brisbane 6.8 RO 300 1978 Marlborough Shire 77.4 RO ,I 1,760 1978 Barrier Reef 6.0 RO " 35,000 1979 Tarong 128.7 RO " 1,920 1980 Heron Is. P&O Hotels 30.0 RO " 35,000 1980
rdnrthPrn Territory Tennant Creek Peko Wallsend 100 RO Permutit 1,900 1980
A large number of RO plants have been installed fairly recently, although some
older plants are still operational: a 5 m3/day plant at Eucla, W.A. has been
operating for 13 years on 16,000 ppm feedwater, although the operators report high
module replacement costs. Earlier RO plants installed by the Australian National
Railway at Rawlinna and Cook have had problems in achieving design capacity and
product purity. This was found to be due to poor pretreatment, and a revised
pretreatment method based on the plant at Manguri (about to be conmissioned), will
hopefully solve the problem. The original plant at Rawlinna, installed in 1969,
was largely replaced in 1975, using a more modern type of membrane. The RO
plants operated at Coober Pedy, S-A., with a difficult 18,000 ppm feed,have also
exhibited high costs attributed to poor pretreatment systems. Water from the
older plant is reported to cost S8.24/m3 although it is sold to the public at
about half this price.
FENTON AND GEROFI 405
Location
TABLE 3 : SOME AUSTRALIAN ION EXCHANGE PLANTS Cactaci tv
CarltonWnited Brew.
Operator
State Elect.
ICI Aust.Newsprint
II
Lurgi
II
Ranger Uranium
1,
State Elect.
I‘
II
II
,t
I,
,I
I,
Dept. of Works
ICI
State Elect.
Nt _ Newman
Dow Chem. fit. Isa Mines
I‘
State Elect. II
Monsanto State Elect . II
II II I‘ ,I I, II li II II I, II **
Monsanto Amp01
State Elect. II I# L1 ,I
Monsanto State Elect.
‘I
im’/dayi Manufacturer Commissioned
East Perth W.A. Wangi NSW Bunbury W.A. Mt. Gambier S.A. Sth.Fremantfe W.A. Wal lerawang NSW Tennyson Q’ld, Port Augusta S.A. Darwin, N-T. Nagwarry S.A. Altona Vie. Mica Creek Q'ld. Mt. Isa Q’ld Vales Point NSil Pyrrnont NSW Footscray Vi c. Calcap Q’ld Munmorah NSW Muja W.A. Rhodes NSW Torrens Is. S.A. Swanbank Q’ld Tennyson S.A. Vales Point NSW Torrens Is- S.A. Collinsville Q'ld. Munmorah NSW Singleton NSW Morwell Vie. Singleton NSW Footscray Vie. Lytton Q’ 1 d Collinsville Q’ld. Wallerawang NSW Gladstone Q’ld Torrens Is. S.A. Kwinana W-A. Footscray Vie. Vales Point NSW Yallourn Vie. Melbourne Vie. Botany NSW Albury NSW &r-well Vie. Jabiru N-T. Gladstone Q’ld Eraring NSW Tarong Q’ld Loy Yang Vie. Osborne Vie Mt. Newman W-A.
590 345 860 164 540 164
590 + 110 540
19,872 15,552 1,360 680 810
545 + 182 1,370 820 430 540 820 540 680 540
2 x 160 1,380 16,356 1,100 4,600 810
2,940 164
1,140 2.050 910
1,140 1,600 2,950 1,900
Permuti t I, ,I II I‘ I, I,
N.E.I.JohnThompson Permuti t
li
N-E-1. Qermuti t
11 I, II
N-E-1. Qermutit
,I I*
N.E.I. II
Pet-m&it I, II
N-E-1. II
Permuti t It
N-E-1. ‘I I,
Permuti t
2,290 1,814 2,160
75 380
2.040 6,120 3,840
1956 1956 1956 1956 1957 1958 1960 1960
1960 - 68 1961 1961 1961 1961 1962 1963 1963 1965 1965 1965 1966 1966 1966 1966 1967 1968
1968, 69 1969 1969 1970 1970 1970 1972 1973 1974 1974 1974 1975 1976 1977 1978 1978 1979 1980 1980 1980 1980 1981 1981
600 500
I.C.I/CSIRO*
* Demonstration Plant - “Sirotherm” Process
406 FENTON AND GJZROFI
Tab1 e 2 includes only one ED plant. Particularly with difficult, lower
salinity borewaters, processes such as the ED reversal system - with their rela-
tively modest pretreatment requirements - might be thought to be competitive with
RO systems. A proposed desalination installation at the tourist village of Yulara
in the N.T. (2 plants of 380m3/day capacity, feedwater 1,480ppm) is presently out
for tender, and an ED system could quite possibly be chosen.
Of the Smineralisation plants in Table 3, most are of the fairly conventional
ion exchange type. The 600m3/day plant at Osborne, S.A. (a demonstration plant)
uses the “Sirotherm” process for thermal regeneration of the resin [8]. This
process has not quite lived up to its earlier expectations because it has been
found impractical to treat waters containing calcium salts, and hence where
calcium is present a first stage to remove the calcium is needed 161. Nevertheless
the Sirotherm process could become quite attractive for applications in the low
salinity large volume range, particularly for low-calcium feedwaters.
POSSIBLE APPLICATIONS
(1) Distillation
It is of interest that no multiple effect plants appear in Table 2. This
should be considered in context: not a single new distillation application has
been implemented in recent years - the newer MSF plants at Moomba were virtually
add-ons to existing units. Potential users appear to have seen the Moomba plants
as a special case because of the cheap natural gas available, and - considering
also the unspectacular performance of the Dampier MSF plant - turned to other
technologies such as RO which was being extensively marketed at that time. The
aurhors feel that RO has been somewhat oversold in Australia, and that potential
users have not kept up with developments in the distillation field. As an
example, water costs using a modern VTE or HTE distillation plant at Coober Pedy
would surely be much less than the $8.24/m currently applicable to the RO plant
now in operation. Even a solar-driven plant could produce water at costs below
this 19, 101.
Developments in multi-effect evaporator (MEE) distillation plants have led to
systems with cheaper capital costs than MSF plants i 111. In addition, MEE plants
can be designed for higher PR’s and require less pumping power than MSF processes.
One particular combination that would appear attractive in more remote regions is
the coupling of waste heat from diesel generators (the predominant source of
electrical power in such regions) with MEE plants. A number of such systems are
available in a range of sizes 112, 131 , with PR’s of 4 - 6.5. Since the thermal
energy for such systems is virtually free, overall water costs should be quite low
and hence very competitive with RO systems - particularly for higher salinity
E-IBTON AND GERmI 407
feedwaters _ If water demand is badly matched to the power demand, then a fuel/
waste heat or possibly a solar energy/waste heat combination might prove cost-
effective.
Where waste heat is not available, the availabilfty of natural gas may make
future distillation plants competitive in some areas. Alternatively, use of solar
energy to drive MEE plants is now approaching economic feasibility for remote
regions f either as collector/plant combinations or - for larger sizes - solar
pond/plant combinations [ 9, IO] . For capacities above about ZOm=/day, collector/
plant combinations produce cheaper water than solar stills [ 91.
For large-scale water requirements in urban environments - such as Perth or
Adeal ide - the most likely source of energy is from power stations, either as
electrical energy or as “waste” heat. The cost of water from combined power/
desalination complexes such as those prevalent in the Middle East is, however,
quite high, and - in any case - the existing Australian power stations have not been built to acconnmdate such a dual role. A recent process which both promises
cheaper water and would cause least disruption to the existing power generation
facilities is Nord Aqua’s Waste Heat Desalination (WHD) system [13, 151. This
system has as its heat source the outlet seawater used for cooling in such processes
as power stations, oil refineries, metallurgical plants, fertilizer plants, fer- mentation plants, etc. This water is generally warmed only about 10°C. but is
available in vast quantities: about 60% of the thermal input to power plants
exits as waste heat. Plants using such small temperature differences to drive
the desalination process have a high pumping power requirement (since a circulation
t-ate Of 100 times that of the product rate is required} and have to remove from
vacuum very large volumes of non-condensible gases. The WHO design makes provision
for these complications and, in areas where such waste heat is available, is
very competitive with conventional distillation processes for desalination of
seawater [ 151: for a given capacity the capital costs are similar, pumping power
costs are comparable, maintenance and labour costs are simjlar, but the thermal
energy cost - which can be over half of total water cost in conventional plants -
is zero for the WHD process.
(2) Reverse Osmosis
While it was stated earlier that RO may have been “oversold” in Australia, there
are many potential applications where RO would be the main contender. The main
problems with RO appear to be in the pretreatment system, with poor pretreatment manifesting itself as high membrane replacement frequency. We see the most cost-
effective applications of RO as:
(a) desalination of brackish borewater (say to 7,OOOppm salinity) - PartiCUlarlY
waters with relatively low silica. Fe, Mn and Aelevels (6) small scale desalination of surface waters or potable water to produce a
very pure product (for large scale applications, ion exchange in more popular)
408 FENTONANDGEXOFI
(c) seawater desalination in regions with either cheap electrical power or where
space considerations are predominant (e.g. for offshore oil and gas platforms)
In most areas of Australia with very brackish borewater (7,000 - 35,000 + ppm),
the authors feel that waste heat
cheaper water. If waste heat is
choice.
processes, described above, will generally produce
unavailable, then RO could still be the best
Solar powered RO is possible, however, the most often-quoted such system -
photovoltaic cells plus RO - has been shown to be unattractive relative to other
solar alternatives for most salinities [ 101, and certainly uneconomic at present
relative to conventional RO using diesel-powered generators.
(3) Electrodiaiysis
As outlined earlier, modern ED systems such as EDR are much less sensitve to
feedwater composition and so can tolerate much simpler water pretreatment schemes.
Since groundwaters in many regions of Australia require extensive pretreatment for
RO, ED should be quite competitive, particularly for lower salinities ( < 3,OOgppm).
ED is not applicable where very pure product water is required, since the amount
of electric current required depends on the amount e f dissolved salt to be removed
and pure water has a very high electrical resistance.
By using a number of stages in series, ED has also been used to desalinate
seawater, however, the cost has been very high. More recent work, particularly on
higher temperature membranes, has increased the range of ED processes, and
improvements in the economics of ED desalination of seawater have been reported
E 161. The cost of desalinating seawater by ED is stil’l considerably higher
than for either distillation or RO. Solar powered ED, like solar powered RO, is
possible but unlikely to be economic.
(4) Vapour Compression
VC is essentially a distillation process, but has been listed separately because
the majority of VC processes require mechanical energy for the compressor, usually
supplied electrically. For small, packaged systems the major advantages of VC
over RO or ED systems are that (a) only minor pretreatment is needed (screening,
chlorination, scale control additives) (b) high product purity is achieved, (c)
very high concentration ratios can be achieved (useful if effluent disposal is a
problem [ 111, and (dj a wide range of feed salinities can be tolerated. However,
because the power requirements for VC are independent of salinity, for low salinity
waters, RO and ED use less power.
For seawater desalination, the power costs for VC and RO are not very different,
however, at least one VC manufacturer ctaims that VC is capable of lower power
consumption C173. Hence for smatt capacity seawater units, such as for offshore
pt atforms VC and RO are in direct competition.
Thermocompression variants of VC plants are available, irhere compression is
accomplished by use of jet ejectors driven by mid-pressure steam. Because jet
ejector5 are fair@ inefficient , SOme of these systems actually have relatively
low energy efficiency. Atso, because mid- rather than few-pressure stean is
required, it is unlikely that waste heat or solar energy could be used as a cheap
source of heat.
One possible extra application of the VC process might be as a portable truck-
rrmunted plant. Many outback areas of Australia are subject Co severe droughts. and
such a unit could be #moved from tavvn to town to at least provide drinking water
for the inhabitants. A VC p‘fant is the obvious choice for such an application
because of the advantages (a) and {d) listed above.
CONCLUSIONS
fiIost of Australia’s major popu?ation centres wit7 be welf supp’lied with fresh
water from conventicnal sources for the foreseeable future. The significant
exceptions are Adelaide and Perth. Several smaller settlements which support
agri cu? tural , mining or railway conmunities are less fortunate than the big cities. For such towns, particularly in S-A. and W-A., desa7ination could in future be
the most cost-effective means of supp‘lying fresh water.
Up to the present, Australian experience with distillation plants has been very
limited and not very favourabfe. Vapour compression plants have been used more
widely, but have suffered scaling problems. Reverse osmosis plants are now the
most co-n type of desatination p7ant installed and are also used in some situations
where other types of processes could well have done the job.
Distillation in Australia can have a future, especially if modern MEE plants
are used and if cheap thermal energy from waste heat is avai7ab7e. Sa7ar ponds
represent another potential source of cheap energy for distillation. The salinity
at which distillation becomes mare attractive than RO depends on energy costs and
on the nature of the feedwater. but there are several tocations in Australia where
distillation plants would be more cos t effective than the existing RO plants,
Low grade waste heat is an attractive means of desalinating high sa7inity waters
where large power stations or other industrial plants with similar cooling
requirements are located.
V& and ED also have potential applications in certain situations_ ion exchange
should continue to find a market for demineralising low salinity waters.
The So’lar Desalination Group is supported by a grant from Saudi Arabian interests,
administered by the Science Foundation for Physics, University of Sydney- This
financia? assistance is gratefully acknowledged.
410 FESTOIi AND GEROFI
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1.
2.
3.
4.
5.
6.
7.
8.
9.
Department of National Resources, “Review of Australia’s Water Resources 1975”. Aust. Govt. Publishing Service (1976). Body, D.N. “Australia’s Surface Water Resources”, in “Land and Water Resources of Australia” ed. Hal lsworth and Woodcock, Aust. Acad. of Technological Sciences, p59-70 (1978) - Blesing, N.V. “Water for Adelaide”. THe Hydrological Sot. of S-A. Conf., Glenside S-A., March (1978). Gerofi , J.P., and Fenton, G.G. “Solar Thermal Electricity Generation in Remote Areas of Australia”, Report 7, Solar Desalination Group, University of Sydney. May (1981). Fenton, G-G., Gerofi, J-P. and Mannik E., “The Potential for Use of Solar Ponds in South Australia”. Chem.Eng_ in Aust_.Vol. ChE6 (l), ~45-48, March-May, 1981). Swinton, E.A. March, ( 1981).
“Desalination, State of the Art - 1980”, Water 8, (1) , ~21-24,
Herbert, L.S. and Moffatt. D.H. “Desalination - A Survey of Australian Plants”, Dept. of National Development, Australia (1970). Stephens, G.K. and Bolto, B.A. “Gesalination by Thermally Regenerated Ion- Exchange Resins”, PACE. ~21-26, June (1977). Gerofi, J-P., Fenton, G.G. and Mannik E., “Solar Distillation - The Solar-Driven Case”, IDEA Conference, Bahrain (1981).
lO.Gerofi, J-P. and Fenton, G-G., “Comparison of Solar RO and Solar-Thermal Desal- ination Systems”, IDEA Conf. Bahrain (1981).
ll.Cox, B. “Trends in Desal ting" , Pure Water, Vol. 10 (I), ~8-10, March-April (1980) 12.Valmet Oy, Brochure 8139, Finland. 13_Atlas-Danmark, Brochure 8469e, Denmark. 14.Saari, R. “Desalination by Waste Heat”, Proc. 6th Int. Symp_ on Fresh Water
from the Sea, Athens Vol. 1 p297-304 (1978). 15.Kranebitter F., “Clean Water from Waste Heat”, Proc. 6th Int. Symp. on Fresh
Water from the Sea, Athens Vol. 1, p283-290 (1978). 16.Lundstrom, J-E. “Desalting Seawater to Less than 4ppm by ED”. Desalination Vol.
32, p259-277 (1979). lSI.Matz, R., and Fisher U. “A Comparison cf the Relative Economics of Sea Water
Desalination by VC and RO for Small to Medium Capacity Plants”, 7th Int. Symp. on Fresh Water from the Sea, 1 p339-350, Amsterdam (1980).
Figure 1. Australia - Annual Figure 2. Australia - Annual Rainfall - mn. runoff - mn.
FENTON AND GEIROFI
Figure 3 (right). Australia - Groundwater saJinity - PPm.
Figure 4 (beJow). Areas in which desalination may be applicable for water supply.
Figure 5. Australia - average daily globa’l insoJation - kNh/m’ &J/m’).
0 looo-7cOo
t2g 7ooo-l4oOG ‘.’ B?
f 63 >54ooO
Figure 6. Location of existing deselination plants.
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