Doosan sees Enpure's patented dissolved air flotation (DAF) and dual-media filtration (DMF) technologies as enabling it to offer pretreatment with its reverse-osmosis (RO) desalination technology. The company expects to improve the competitiveness of its capabilities in both the reverse osmosis and water/wastewater treatment businesses through this acquisition.

Founded in the early 1970s with its headquarters office in Birmingham, Enpure is a process engineering company with world-class design and fabrication capabilities related to pretreatment and water/wastewater treatment systems and plants. As of 2011, the company had more than 250 project references with around 160 employees and revenue of £ 55.6 million.

"The desalination industry is now expanding through the development of RO technologies," stated Seokwon Yun, CEO of Doosan's Water Business Group. "With the acquisition of Enpure, Doosan has further strengthened the competitiveness of its RO technologies in addition to creating a platform for accelerated growth in the water/wastewater treatment market through engineering know-how based on the company's long list of project references."

NanoH2O, Inc., manufacturer of the most efficient and cost effective reverse osmosis (RO) membranes for desalination, today announced that it has been awarded the prestigious Patrick Soon-Shiong Innovation Award by the Los Angeles Business Journal. The company was selected from among twelve other finalists for playing an important role in enhancing the economic competitiveness of the Los Angeles region.

"This special award program was created with the vision to honor and acknowledge the people and organizations that continue to stretch the boundaries," said Matthew Toledo, Publisher and CEO of Los Angeles Business Journal. "[The award is named after] Dr. Patrick Soon-Shiong, a local example of a passionate entrepreneur who is emblematic of how the innovative spirit drives economic value. Congratulations to this year's thirteen finalists – each of whom continues to inspire us and provide invaluable contributions to keeping Los Angeles at the forefront of innovation."

The Shuwaikh Seawater Reverse Osmosis (SWRO) Desalination Plant in Kuwait has avoided reduced production and plant shutdown - problems caused by red tide - through its pre-treatment steps, according to Pentair X-Flow.

Located near Shuwaikh port, the plant was built by Doosan Heavy Industries and Construction in 2010 for the Kuwaiti Ministry of Electricity and Water.

With an ultrafiltration (UF) permeate capacity of 350,000 m3 and Reverse Osmosis (RO) output of 94,700 m3, the plant supplies drinking water for more than 450,000 residents in Kuwait City.

Pentair X-Flow said the plant design gave special attention to pre-treatment as the seawater in the area is highly saline, rich in organic components and known for occasional red tides, which can last for 10 days. This resulted in a combination of dissolved air filtration (DAF) and Pentair X-Flow’s Seaguard 40 UF membrane modules and skids.

Together, DAF and UF efficiently remove high concentrations of suspended solids and small-sized colloidal particulates. The produced RO feed water has a consistent silt density index value of less than 3.0 at all times, according to the company.

Even during a red tide event, the combined DAF and UF pre-treatment proved successful in removing the increased number of particles caused by the abnormal algae growth with turbidity levels of up to 31 NTU.

Oman's first IWP will involve a 190,000 m³/d reverse-osmosis seawater desalination plant constructed on a build-own-operate basis over a 20‑year period. Commercial operation is expected to start in September 2014.

Oman's daily water demand currently amounts to about 700,000 m³ and is expected to continue growing by 2‑3% per year. Demand is notably increasing in the metropolitan area centered on Muscat, and the Government of Oman is planning to launch multiple IWPs to address the situation.

The Al Ghubrah project is expected to cost up to approximately ¥ 30 billion (US$ 377.8 million) in total and is planned to be funded by Japanese financial institutions through a project finance scheme. Sumitomo and Malakoff will each invest in 45% of the shares of the project company as major shareholders. The two companies will also establish an operation and maintenance company.

Spanish contractor Abengoa announced the start of the US$ 125 million project on November 19, 2013.

The SWRO plant will have a capacity of 60,000 m³/d. Abengoa will be responsible for design and construction, as well as subsequent maintenance and operation for a 25-year period. The work is expected to take 24 months and will create some 400 direct and indirect jobs.

Revenues from water sales are forecast to exceed US$ 1,300 million during this time. The plant will enable drinking water to be supplied to more than 500,000 residents in the towns of Teshie, Nungua and Tema.

This project will increase Abengoa's installed water desalination capacity to nearly 1.2 million m³/d.

Degrémont was chosen by the National Water Company to provide, install and commission 33 modular 5,000 m³/d treatment units, each consisting of two multimedia filter units for pretreatment, two RO units and a chemical treatment unit.

The first contract involves 26 containerized modules, distributed across 13 separate sites, the largest of which is Salboukh, processing up to 30,000 m³/d. The second is for a single site at Al Buwaib, where 7 modules processing up to 35,000 m³/d will be installed in a permanent building.

Suez said on 23 November 2012 that the contracts were won through international collaboration and the combined expertise of Degrémont's operational entity in the Middle East and its subsidiary Water & Power Technologies in Salt Lake City, USA, which specializes in modular and containerized processing units.

The Santa Clara Valley Water District is building a state of the art water recycling plant that could someday make even the dirtiest water drinkable.

The water from the new facility will not be for drinking. Instead it will be used for irrigation and industry. But the technology could one-day be used to clean even waste water.

It is an elaborate and intricate system of pipes and tanks, pumps and valves designed to produce the most basic of our needs water.

"The water that doesn't make it through, or the reject, or concentrate we call it, goes for a second pass," construction manager Gary Ohea said.

The new water purification center has a state-of-the art, three step process that will recycle even the dirtiest water.

"Recycled water is drought-proof, it's water that's in our county that we can use, it's water that otherwise would be going to the bay, so we're being wise stewards of the resource," water district spokesperson Jim Fielder said.

It's still under construction, but when done in mid-2013, the $65 million center will make up to 10 million gallons of highly purified water a day.

The three-step process involves microfiltration, where water is pushed through a membrane with holes one-three-hundredth the width of a human hair, then reverse osmosis, where it's forced at high pressure through a membrane with holes so small water molecules are virtually the only things getting through, and then disinfection with ultraviolet light.

"They're basically stainless steel shell; inside of the shell in contains 40 UV bulbs that run the length of the shell," Ohea said.

The result should be water that's many times cleaner than the average tap water now available in Santa Clara County.

But don't watch for it coming out of your faucet any time soon.

"This will be a test facility to really help us learn from, as we get this thing online, to learn as we treat, what are the various challenges we face and how can we overcome them through the technology," Fielder said.

This desalination facility is coupled to the Madras Atomic Power Station (MAPS), and deploys both multi-stage flash (MSF) evaporation and reverse osmosis (RO) membrane separation technologies. The total capacity of NDDP is 6.3 million litres per day (MLD).

Multi-Stage Flash (MSF) evaporation plant produces 4.5 million litres per day of distilled quality water and Reverse Osmosis (RO) plant produces 1.8 million litres per day of potable-quality water. The desalination plant meets the entire pure water requirement of Madras Atomic Power Station (MAPS).

"The multi-stage flash technology works on the principle of flash evaporation wherein the temperature of water is increased under pressure and then flash evaporated by reducing the pressure gradually in multiple stages," said Shri. M.M. Rajput, Plant Superintendent, NDDP, BARC Facilities, Kalpakkam.

In an MSF plant, by increasing the pressure of water by 2 bar, the boiling point temperature of water is raised up to 121 degree C. The superheated water is then allowed to cool in steps of 2 degree C at each of 39 stages, and the water is allowed to flash evaporate and condense as pure water by reducing the pressure.

The small part of the low pressure steam (at 130 degree C) that goes from MAPS’ high pressure turbine to low pressure turbine is used for heating the sea water. "The pressure drop across the flashing stages will be more at the initial stages and reduces gradually with decreasing temperature," said Shri. C. Balasubramaniyan, Deputy Plant Superintendent, NDDP, BARC Facilities, Kalpakkam. "Temperature drop from 119 degree C to 117 degree C is achieved by reducing the pressure by 1,300 mm water column. But at the lowest temperatures, say 42 degree C to 40 degree C, the pressure drop will be only 100 mm water column."

In short, when the pressure drops, the boiling point of seawater also drops. The excess heat, in turn, causes seawater to flash evaporate into pure water vapor. The water vapor is then condensed to produce distilled water.

But the challenge in the MSF plant comes from making the water flash in 39 stages through a small and controlled temperature drop of just 2 degrees per stage. So much so, that water continues to flash even when the temperature reaches as low as 40 degrees C at 39 stage — the last and final stage!

"If the entire quantity of superheated water is allowed to flash and produce steam at one instant, the amount of water produced will be several times less than multi-stage flashing," Shri. Rajput explained.

In the MSF plant, the scientists have achieved production of more than 9 kg of water from every kilogram of steam produced.

This has become possible as the system is designed to recover most of the heat internally. As the superheated seawater continues to lose temperature at every stage of flashing, the incoming sea water used for condensing the steam, in turn, gains heat. "The sea water used for condensing the steam gets heated to 113 degree C by the time it leaves the heat recovery stages," said Shri. Rajput. "The temperature of the seawater has to be raised by a mere 8 degree C (from 113 degree C to 121 degree C) before it is flashed multi times to produce distilled water."

"The cost of producing distilled water using MSF technology is 10 paisa per liter, and 6 paisa per liter in the case of reverse osmosis," noted Shri Amitava Roy Facility Director, BARC Facilities at Kalpakkam. This is after factoring in the cost of power, steam, chemicals, maintenance and depreciation.

Water Resources Group (WRG) announced on December 4, 2012 that its subsidiary Water Resources International (WRI) had signed a memorandum of understanding with Knowledge Industry Company (KIC) of Saudi Arabia.

WRI will supply its Advanced Seawater Reverse Osmosis Desalination System (ASWRO) to be powered by hybrid wind and solar energy systems. To kick-start the agreement, WRI will supply and operate an ASWRO pilot plant for a major client in Saudi Arabia.

KIC is developing community-scale desalinated water-supply projects using power from renewable energy sources. To penetrate the local market, KIC is funding the installation and commissioning of the first ASWRO plant in order to secure exclusive commercial supply rights from WRI.

The commercial-scale pilot plant, which is expected to be operating in the third quarter of 2013, aims to demonstrate the economics of powering WRG's chemical-free, low-cost modular system by hybrid wind/solar energy. The group currently does not have a plant in commercial operation.

Within a participation and supply agreement due to be finalized by the end of 2012, WRI will manufacture and supply commercial-scale ASWRO systems to KIC with production capacities of 20,000‑40,000 m³/d. These systems are capable of servicing the needs of towns, industries and regional property developments.

The feature that WRG hopes will sell its ASWRO package, which is otherwise a normal SWRO system, is its Plasma Chemical Reactor (PCR), which is a device for creating low-cost ozone from ambient air for pretreatment. This would be effective on difficult organics and might reduce biofouling.

However, Neil Palmer, CEO of the National Centre of Excellence in Desalination Australia warns that care needs to be taken with this approach "because ozonating or chlorinating/dechlorinating organics without effective removal just makes them more tasty to the bugs."

WRG, which was launched in 2007, has its technical and manufacturing operations based in El Dorado Hills, California, USA.

By Leo Kent

In places like Singapore, where fresh water is scarce, one method to obtain drinking water is to filter out the salt from seawater. The usual process for doing this is known as reverse osmosis. Using membrane filtration technology, the salt is filtered out and chucked back into the sea. But this is an expensive, energy intensive process which is causing environmental damage to our oceans.

Biomining

Research engineer, Damian Palin, says, "The technology in reverse osmosis is reaching a plateau in terms of the amount of energy used versus the fresh water produced. Another drawback is the resulting brine which is produced. This is a super salty solution which is generally pumped back out into the environment with dire consequences."

But Palin has come up with a solution: instead of chucking the brine back into the sea, why not use it as a resource in itself?

All you need is a bacterial strain which is able to precipitate minerals, water and food such as sugar

Palin explains, "I became fascinated by biological precipitation or biomineralization, which is a process where organisms form minerals under low energetic conditions – bacteria can do this as a form of defence on their cell surface and so I began to think about microbally inspired low energy production processes employing this technique."

Harnessing nature

The idea at its heart is quite simple as all you need to do is provide the right setting and let nature take its course. He says, "All you need is a bacterial strain which is able to precipitate minerals, water and food such as sugar."

This form of biomining means that various minerals can be extracted without having to apply heat or use toxic chemicals, both of which are environmentally unsound. Currently, Palin is testing different bacterial strains to see what minerals they extract from the brine.

So far we have achieved proof of concept and the findings of our experiments have been submitted for publication

He says, "To date I have worked with bacterial strains that are able to precipitate calcium carbonate and various magnesium carbonates, but it seems that certain strains have a degree of control over the minerals and hence the metals they precipitate. Understanding these processes may allow a revolution in manufacturing and material production techniques."

Billion dollar industry

Singapore is aiming to produce 900 million litres of desalinated water a day by 2060. Palin believes that mining the leftover brine for metals could be a billion dollar industry. It is a nascent concept however, and a lot more testing is required to see if it really could be commercially viable. Palin says, "There has been lots of interest but the technology is very much in its infancy. So far we have achieved proof of concept and the findings of our experiments have been submitted for publication."

Though it may be wise to remain cautious this early on in testing, the very idea of harnessing what occurs naturally and utilizing waste is an ingenious concept that could serve as a model for other forms of industry.

Forward osmosis: is China next to shake up the desalination sector?

After completing installation of its second forward osmosis facility in Oman, Modern Water is now expanding eastwards with an agreement signed in China.

The UK-headquartered company has signed a Framework Agreement with Hangzhou Development Center of Water Treatment Technology (Hangzhou Water), in the People’s Republic of China.

The aim of the partnership will be to jointly identify and develop projects in China, including seawater desalination plants and other water-related opportunities.

In September Modern Water said it had completed commissioning of its 200 cubic metre per day forward osmosis desalination plant at Al Najdah in the Al Wusta region of Oman (see Water & Wastewater International magazine story).

Hangzhou Water is owned by National BlueStar (Group), which is part of the state-owned China National Chemical Corporation. Hangzhou Water specialises in membrane systems for industrial uses such as seawater desalination, industrial pure water preparation and water reuse.

The company owns four mainstream technologies-electro-osmosis (ED), reverse osmosis (RO), ultra-filtration (UF), and microfiltration (MF). It also has production lines for membranes of RO, NF, UF, and MF, and manufactures and sells 23 product lines in five sectors.

Hangzhou Water has won or been involved in approximately 60% of China’s current or planned desalination projects. Hangzhou Water has engineer, procure and construct (EPC) contracts as well membrane manufacturing and fabrication facilities.

Improved membrane materials are now allowing large scale desalination facilities to come online, with the 444,000 m3/day Victoria desalination plant in Melbourne, Australia recently opening for business and the 510,000 m3/day Soreq plant in Israel expected soon.

While RO technology – requiring pressure to force seawater through membranes and leave behind contaminants – is gaining traction and confidence globally, forward osmosis is still in its infancy on a widespread, commercial scale in comparison.

The latter instead requires a draw solution to create a driving force for freshwater to pass through the membrane.

Modern Water calls its process Manipulated Osmosis, with the first plant located in Gibraltar supplying water for public consumption from May 2009. The company claims that energy consumption can be up to 30% lower than conventional reverse osmosis.

Last year Modern Water’s Monitoring Technologies division in the country contributed sales of more than £500,000 to the group.

Neil McDougall, executive chairman of Modern Water, said: "Sources estimating the industry in China will see new investment of up to RMB20 billion (US$3.2 billion) over the next four years."

With MemFis BD BlueSystems presents an innovative membrane filtration system for use in livestock management which converts manure and fermentation residues into clear water, valuable fertilizer and useful input material for biogas plants in three process stages.

The Big Dutchman company has successfully eliminated the weak points of existing, technically elaborate systems, which have a high energy consumption and which also involve a high cost factor. This was possible also due to the use of innovative technologies which have already proven themselves in two years of practical use. The result is a compact system which is delivered ready for installation on a foundation block.

The three-stage MemFis filtration process includes solid-liquid separation, ultra-filtration and as a last stage reverse osmosis. Of special importance is the second filter stage which features a special "oscillating" membrane. Thanks to this innovative solution there are no more problems with clogged membranes which have so far been a common problem in existing filtration systems. This results in significantly reduced cleaning requirements, a much improved permeability of the organic ingredients and therefore a stable, long-term operation of the entire system.

Input materials can be pig or cattle manure or fermentation residues. MemFis processes these residues so efficiently that in the end approx. 50 per cent of the input material is converted into distilled-like water which can be discharged into a water reception pond or can be used as part of the drinking water resources for livestock or for cooling or cleaning purposes on the farm. The remaining material can be used or sold as input material replacement in biogas plants or, if the liquid concentration is high enough, also as liquid fertiliser.