Seawater Desalination Equipment
Seawater Desalination Equipment
HOLLOSEP® RO Module features High Water Recovery Rate
Seawater desalination equipment provides fresh water for drinking and industrial use by removing the various salts in seawater, and turning salt water into fresh water. Desalination plants have traditionally used the evaporation method whereby seawater is heated and the vaporized steam cooled to obtain pure water. The evaporation method, however, requires large-scale facilities as well as large quantities of fuel for heating, and the water recovery rate is low, at less than 20%.
Toyobo initiated research on desalination using reverse osmosis membranes over 30 years ago. In 1978, we successfully developed the cellulose triacetate (CTA) hollow fiber membrane and the HOLLOSEP® module, which packs CTA hollow fibers together into a large element. This RO membrane using CTA material has superior pressure resistance. It can withstand pressures of 70-80 atmospheres when extracting fresh water from seawater, and has a high water recovery rate of 40-60%. Moreover, the CTA material has strong chlorine tolerance, so the module allows chlorine disinfect, which facilitates easy maintenance by checking the propagation of microorganisms within the module and preventing clogging. When seeking markets which should have the greatest demand for the HOLLOSEP® RO membrane module, we focused our target on the nations of the Middle East, which struggle to secure water resources. We were confident that HOLLOSEP® would win customers from its technical superiority offering easy maintenance, even when used for the waters of the Red Sea and the Arabian Gulf with their high salinity and bacterial content. The engineer responsible for the development work also had a burning desire to propose this new desalination method to the people of the Middle East, who were making fresh water using the evaporation method.
Trailer Road Show
However, it was not easy to gain the understanding of the local people. They were not eager to change the method they had been using. So we came up with the idea of loading our equipment onto a large trailer, and bringing it to potential customers for direct comparison with local plants. We were confident we would gain their understanding once they were shown the technological superiority of our product - once they saw just how efficiently HOLLOSEP® produces fresh water. And the strategy worked. Many customers decided to adopt HOLLOSEP® as soon as they saw the demonstrations with their own eyes.
Our steady, energetic sales activities started to bear fruit from the mid-1980s. As the news of its high efficiency and reliability spread by word of mouth, desalination plants adopting Toyobo's HOLLOSEP® were built in Arabian Gulf and Middle Eastern countries one after another. HOLLOSEP® has now gained a market share of around 50% for large desalination plants in the Gulf cooperation council (GCC). As securing water resources has become an urgent issue, the fields which require HOLLOSEP® are expanding across the globe. The Toyobo Group has positioned the water processing membrane business as a growth field, and we are contributing with our membrane technologies.
Local Production of Reverse Osmosis Elements
Toyobo has reached an agreement with ITOCHU Corporation and ACWA Holding of Saudi Arabia to establish a joint venture for the manufacture and sale of reverse osmosis membrane elements for desalination in Saudi Arabia. A signing ceremony was held in the capital Riyadh on February 16, 2010. The joint venture was established in June 2010, and is scheduled to begin production from March 2011.
CTA Hollow Fiber Membranes Receive Biomass Mark Certification
Toyobo CTA hollow fiber membranes, which have achieved a solid performance record and earned high praise as reverse osmosis membranes for seawater desalination, were certified as products which meet the Biomass Mark labeling criteria in June 2010. By improving the structure of the modules which hold these hollow fiber membranes, Toyobo has greatly increased the per module water production capacity, which makes the modules more environmentally friendly. Toyobo modules packed with CTA hollow fiber membranes are being used in Arabian Gulf and Middle Eastern countries, and contribute to the production of fresh water from seawater.
Explanation of Terms
- HOLLOSEP® is a hollow fiber reverse osmosis membrane module which filters out ions and allows only water to pass through. It is used to make drinking water quality water from seawater, and to make pure water and water for pharmaceuticals production from tap water and water for industrial uses.
- ●Reverse Osmosis (RO) Membranes
- Reverse osmosis membranes let water pass while rejecting ions, salts, and other impurities. These are commonly referred to as RO membranes.
- ●Hollow Fiber Membranes
- Hollow fiber membranes are straw-shaped hollow fibers which provide the filtration function. The hollow fiber structure increases the membrane surface area per unit space. Hollow fiber membranes are widely used in home water purifiers, for industrial uses, and at water treatment plants.
- ●Cellulose Triacetate (CTA)
- CTA, also known as Triacetate and TAC, is manufactured from Cellulose and acetate ester. Chemically, the hydroxyl groups in the cellulose have all been transformed to acetate. CTA is used in fibers and plastics.
- ●Biomass Mark
- The Biomass Mark is an environmental product label which certifies that products contain materials derived from living organisms (biomass) and meet quality and other related standards, laws and regulations. The inspections and certifications are conducted by the Japan Organics Recycling Association, and 236 products were certified as of April 2010.