Water. desalination + reuse

PROJECTS | 20 | Desalination & Water Reuse | May-June 2014 parameters and demonstrate its reliability. A red tide event will be simulated during this piloting campaign to demonstrate and confirm the required performance of the DAF. ILF has been engaged as ESC's technical advisor for tender preparation and evaluation, and as owner's engineer for the project execution and warranty periods. F1 IWPP's SWRO extension project presents a number of features that are unique in the industry and which offer a great degree of innovation in terms of energy efficiency and emissions reduction. In fact, technical solutions proposed during the planning and optimization phase have allowed ESC to overcome physical limitations in retrofitting the existing F1 plant and gain significant power and carbon footprint savings. One of the most innovative aspects of this project is that it is able to recover seawater discharge from F1 IWPP's multi-stage flash (MSF) unit, blending this with fresh seawater from its seawater intake point for use as feedwater for both plants. Aside from reusing the seawater, this also fully integrates seawater streams for the thermal desalination and SWRO plants. Under design conditions, 478 m 3 /d will be extracted by the existing RO pumps, 163 m 3 /d will be extracted from the MSF reject and 185 m 3 /d will be extracted by new pumps that will be installed for the new SWRO plant. This reuse of the MSF reject water has resulted in a substantial optimization of the energy requirements of the plants because: l It has allowed for the size of the seawater supply pumps to be considerably reduced, resulting in reduced energy consumption to run these pumps l Seawater supply temperature at the membrane inlet is maintained at a higher level, enabling the reduction of feed pressure at the 1st pass inlet. The reuse of MSF reject water has also allowed the existing structure of the seawater intake system to remain unchanged, which has led to substantial capex savings. Optimizing seawater feed to the new SWRO plant has allowed the F1 IWPP to achieve very competitive specific power consumption levels. The specific power consumptions are 3.3-4.0 kWh/m 3 , while the final energy consumption of the plant built by Acciona will be 3.6 kWh/m 3 . This latter value includes energy consumption by the electric utilities associated with the DAF (which has an inherent power consumption of 0.05 kWh/m 3 ). This represents an extremely competitive specific power consumption level relative to industry benchmarks, as can be seen in Figure 4 opposite. Furthermore, this model of seawater abstraction further minimizes the environmental impact of the plant, since its seawater requirements are deemed to be extremely low, resulting in: l Minimal additional chlorine required for disinfection l Reduced environmental impact from brine discharge. In summary, the Fujairah 1 IWPP's SWRO extension represents the optimal solution to take advantage of the co-location of RO and thermal desalination plants for better efficiency and a reduced environmental impact. l 0 5 10 15 20 25 30 35 Figure 4: Power consumption benchmark ENERGY CONSUMPTION kWh/m 3 Min Max RO Gulf RO Indian Ocean RO Red Sea MSF F1 ext 4.5 6.5 3.5 5.0 35.0 20.0 4.0 3.3 6.0 4.0 READ OUR SPECIAL DIGITAL EDITION AT: www.desalination.biz/digitaledition www.desalination.biz/digitaledition We are trialing a new format for the international desalination industry direct to your laptop, tablet and phone with a special Desalination & Water Reuse digital edition. D&WR on the move D&WR We want to know what you think, tell us at: www.desalination.biz/survey With this format, you'll have: · Immediacy of information — receive the latest issue before your print edition · Easy to read on any device — desktop, laptop, tablet or smartphone · Easy to access · Downloadable and printable information

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