Richard White, Biwater’s project engineering manager, told
WDR that the firm had been pre-qualified by AECOM, the
owner’s engineer, and the selection was made by Ortega
Industrial Contractors, the general contractor constructing
According to White, the two-train BWRO system will be part
of a water treatment plant that reclaims 2.45 MGD (9,273
/d) of surface runoff water and demineralizer wastewater
from an existing pond on the WTE site. The pond water,
which has a TDS of 1,900-3,300 mg/L, is pretreated using
coagulation, clarification and microfiltration, before being
introduced to a 60,000 g (227 m3
) break tank.
From the break tank, 2.2 MGD (8,327 m3
/d) of pretreated
water undergoes cartridge filtration before it is fed to
Biwater’s two-train RO. The three-stage system is configured
in a 16:8:4 vessel array with seven elements per vessel,
although provisions have been made for future expansion
to a 20:10:5 arrangement. Each train is fed by a dedicated
high-pressure feed pump and two inter-stage booster pumps,
and designed at a minimum system recovery of 87 percent.
Approximately 0.3 MGD (1,135 m3
/d) of the 50 mg/L TDS
permeate will be used directly for boiler feedwater, while the
remaining 1.6 MGD (6,056 m3
/d) will be blended with 0.55
MGD (2,082 m3
/d) of pretreated water from the break tank
for use in the cooling towers. The RO concentrate will be
discharged to the sewer.
Plans currently call for the system to be commissioned in
EPC contractor selected for BWRO
Italy’s OSMO Sistemi has been selected to supply a 17,280
/d (4.6 MGD) BWRO system for Office National de l’Eau
Potable’s (ONEP) Dakhla project in southern Morocco.
Negotiations for the MAD100 million ($11.8 million) EPC
project – which was initially planned as a SWRO before
ONEP switched to a brackish groundwater source – are
nearing completion, and the project should be awarded by
Evangelos Kantilaftis, OSMO Sistemi’s managing director,
a TDS of approximately 2,500 mg/L, and the pretreatment
system will include ammonium and H2
S removal in addition
to sand filtration. Commissioning is expected to take place
OSMO Sistemi is a member of the Cyprus-based
Page 2 WATER DESALINATION REPORT – 30 January 2012
Bureau of Reclamation brought desal experts from around
the world to Alamogordo to discuss ways to advance desal
projects employing RE and to develop research projects and
potential collaboration opportunities.
Last November, CambridgeIP released a patent landscape
report prepared for the World Intellectual Property Organ-
ization entitled Desalination Technologies and the Use
of Alternative Energies. The report notes that progress is
being made in advancing the integration of desal and RE
sources, and that continued development and deployment of
desal technologies powered by RE sources could provide a
more affordable fresh water source for both developed and
developing countries now under threat of water shortages.
The report shows that the growth in the number of desal/RE
patent applications and patent families – i.e., multiple patents
in more than one country protecting the same technology or
invention – has grown from a total of about 800 in 1980 to
more than 4,550 in 2011. Although the number of patents
is not an indication of an RE technology’s desal integration
suitability, it does provide some insight into the potential
relevance based on the level of research activity.
Last week, the World Bank held an internal workshop to
review a draft of a new report on the integration of RE with
desal as an emerging solution to close the growing water
gap in 21 Middle East and North Africa (MENA) countries.
The report was prepared by a team led by Bekele Debele
Negewo, a senior water resources specialist in the World
Bank’s MENA region.
According to Dr Debele, “Simply put, there is not enough
freshwater to maintain MENA’s economic growth. The
region’s water deficit will grow to 200 billion m3
2050 and closing this estimated $104 billion deficit will
be challenging. Demand management should be the first
priority. However, desalination will remain important in
MENA, and RE should be part of the energy mix to ensure
That logic is universally applicable.
Waste-to-energy plant will get RO
Biwater AEWT has been selected to supply a 2 MGD (7,570
/d) BWRO system at Pinellas County Utilities’ waste-to-
energy (WTE) facility in St Petersburg, Florida. The solid
waste facility will use the RO system to treat water from an
existing pond for use as boiler and cooling tower makeup
water at the WTE facility, which processes about one million
tons of garbage every year, producing up to 60 MW of
electricity for distribution within the nearby community.
Page 3WATER DESALINATION REPORT – 30 January 2012
“Although the plants employ all of the energy efficiency
features of a modern, state-of-the-art SWRO plant, the main
goal of TAOZ operation is to minimize energy cost, not the
specific energy required per cubic meter of water produced,”
Building a desal plant based on a load and time variable
electricity tariff is more expensive than building one that
operates at a flat capacity because there are many hours when
the plant’s production capacity is only partially utilized.
Plant production can be reduced dramatically, twice a day
and by up to 60 percent within a half hour time period. This
requires changing recovery ratios, feed flow rates, pressures,
fluxes, chemical dosing and more.
While this type of operation is complicated, it does reduce
equipment wear, shortens startup times, saves water for
flushing and shortens the time to stabilize the process and
water quality after the change. It is also the only way that
one can imagine achieving a total water cost of $0.585/m3
For new readers and those regular readers who may be
mystified by WDR’s use of various units of measure in our
stories, we offer the following explanation:
Nothing illustrates the local complexion of the global desal
market more than the units used to measure a facility’s
production capacity. The primary units of measure used in a
WDR article are those used by the facility that is the subject
of the article itself, or those commonly used in the region in
which the facility is located.
The most frequently used and universally understood unit
used to measure water volume is the cubic meter (m3
Conveniently, a cubic meter of water weighs one metric ton.
The term many Australasian countries use to measure water
volume is the megaliter (ML), which equals one million
liters, or one thousand cubic meters.
Americans measure water volume using the US gallon, and
plant capacity is described in terms of million gallons per
day (MGD). However, many Western US states rely on the
acre-foot (ac-ft, or AF), a unit used in agriculture to describe
the volume of water that would cover a one-acre area to a
depth of one foot.
Many Middle Eastern countries measure desal plant output
in million Imperial gallons per day (MIGD), where one
Imperial gallon is 20 percent greater than a US gallon.
flexibility offsets high energy costs
All large-scale SWRO plants installed in Israel have been
designed with hourly peak production capabilities that are
much higher than their nominal capacities would indicate.
The Sorek plant, profiled in last week’s WDR, is one example.
Sorek’s production capacity is generally referred to as being
150 million m3
/y. This equates to an average of 411,000
/d (108.5 MGD), or 17,125 m3
/hr (4.5 Mgph). However,
the plant actually has a maximum production capability of
/hr (6.9 Mgph), which equates to 624,000 m3
(164.9 MGD), or 227.8 million m3
The 51 percent increase in Sorek’s maximum production
capacity over its contracted production is necessary due to
the country’s seasonal fluctuation in water demand, and this
also allows plants to reduce production during the day, when
electricity tariffs are at their highest, and increase production
during nighttime, off-peak periods when electricity tariffs
are significantly lower.
IDE’s Yaron Egozy told WDR that the monthly/bimonthly
production quantities differ from month to month because
the summer production requirements are much higher than
the winter requirements.
“The daily production quantities change from day to day and
are limited within minimum and maximum boundaries. The
hourly production also changes from hour to hour based on
Israel Electric Company’s load and time variable electricity
tariff [TAOZ]. According to this tariff plan, shown below,
there are three different levels of electricity costs, depending
on the time of day: a peak, shoulder and base tariff.
“The changing electricity prices dictate the hourly production
capacity, and our plant designs are based on two modes of
operation: maximum water production at low electricity
rates and minimum water production at high electricity rates.
Electricity Prices at Variable Tariffs
The use of the various units is further complicated when
projects are delivered on a BOO or BOT basis and a plant’s
production capacity is expressed on a per-year, rather than
per-day or per-hour basis. When projects are described in
terms of million cubic meters per year (MCM/y) – or when
US plants are referred to in terms of acre-feet per year
(AFY) – the volumes do not reflect the actual production
capacity of a plant, but rather, the amount of water the plant
has been contracted to furnish over the course of the year;
the actual production capacity is usually significantly higher
(see “Energy Cost” story, this issue).
In most WDR articles, a secondary unit is routinely included,
parenthetically, as a reference. Some frequently used
volumetric units and their conversions are:
• 1 cubic meter = 264.2 US gallons, or 1,000 liters
• 1 US gallon = 3.785 liters
• 1 Imperial gallon = 1.2 US gallons, or 4.546 liters
• 1 acre-foot = 325,900 US gallons, or 1,233.6 m3
• 1 megaliter (ML) = 1,000 cubic meters
• 1 gigaliter (GL) = 1 million m3
• 100 million m3
/y = 72.4 MGD (avg)
• 1 MGD = 1,120 acre-feet/year (AFY)
• 1 gigaliter = 1,000,000 cubic meters
Desal advocacy group formed
Prompted by the state’s recent drought and the resulting water
shortages, desal boosters have formed the Texas Desalination
Association (TDA), a non-profit trade organization that will
focus on developing mechanisms for making desalination
Kyle Frazier, an agent for the group, told WDR that the
Austin-based organization will advocate on behalf of desal
technology before the Texas Legislature and regulatory
agencies and will work to streamline the regulatory process.
“We will bring together experts in desal technology with
those who need new sources of water,” he said.
The TDA is now finalizing the organization’s by-laws and
establishing a nine-member board of directors. Membership
is open to public utilities, municipalities, desal companies
and technologists, academics and private citizens.
For more information, contact Kyle Frazier at jkf1@texas.
net. The website, www.TexasDesal.org, should be online
later this week.
New York’s Department of Environmental Conservation
(DEC) has accepted United Water’s Draft Environmental
Impact Statement (DEIS) for the proposed 7.5 MGD (28,385
/d) Haverstraw Desalination Plant as complete. Public
hearings are scheduled for 28 February and, last week, the
DEC agreed to extend the public comment period by an
additional month, to 18 April. United Water has conducted
a one-year pilot study at the plant site in Haverstraw, on the
Hudson River’s western shore, 35 miles north of New York
City. The plant is planned to be operational in 2015.
Earlier this month, the Environment Agency-Abu Dhabi
(EAD) announced that it had completed the construction
of 22 solar-powered BWRO plants across the Emirate.
Each unit consists of 300m2
) of solar panels that
generate approximately 35 kWh to produce 30 m3
GPD) of fresh water. The pilot project is intended to provide
findings that will help reduce the capital cost and increase
the efficiency of future units.
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Page 4WATER DESALINATION REPORT – 30 January 2012
The NationalWaterResearch Institute (NWRI) will accept
nominations for its 19th Annual Athalie Richardson Irvine
Clarke Prize for excellence in water research. The Prize is
awarded to individuals contributing towards the discovery,
development, improvement and/or understanding of the
issues associated with water quality, quantity, technology or
public policy. Last year’s recipient was Duke University’s
Mark Wiesner. Nomination procedures are available at:
Zulal Water Technology’s Tripoli office has announced that
it has resumed full operations in Libya. The company said
that it has already restored water and wastewater operations
for a major oil company and has received an order to supply
emergency water at another oil production facility.
NanoH2O has released Version 1.2 of its Q+ membrane
projection software. The new version provides an option for
permeate split flow calculations and the ability to convert
the results report into PDF formats. The software can be
downloaded at www.nanoh2o.com/software-tools.
A Solar-powered BWRO Plant