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Forward Osmosis: Desalination Membrane Processes Forward Osmosis: Desalination Modern Water owns, installs and operates world-leading membrane technologies and we are the world-leader in Forward Osmosis (FO) technology. We have successfully implemented and operated our patented desalination process internationally and produce fresh water in some of the most demanding seawater conditions in the world. Our FO process consistently delivers significant reductions in FO desalination benefits operational costs, reduced lifetime costs and it reliably produces high quality product water, even in the most challenging conditions. A proven, reliable and robust membrane process We use our world-leading FO technology platform in a number of Energy consumption membrane process applications other than for seawater or brackish typically up to 30% lower water desalination. These include: evaporative cooling systems, than conventional Reverse secondary oil recovery and the development of renewable energy Osmosis (RO) using hydro osmotic power (HOP). Inherently low fouling characteristics (both particulate and biological fouling) Significantly reduced product boron levels without post-treatment when compared to conventional RO Higher availability than a conventional RO plant due to low fouling, simple cleaning and ease of operation Forward Osmosis Vs Reverse Osmosis 1 Technology Status 3 Membrane Fouling 4 Energy Consumption Operational Costs Boron Removal Ease of Operation Capital Cost Innovative process solution now Extremely low inherent Typically up to 30% less than RO. Less than RO due to higher Inherently high removal, without Very similar to RO, but with less Similar capital cost on a fully operational & commercially fouling - low pressure, diffusion The more difficult the feedwater availability, less chemical the need for post treatment frequent cleaning and increased like-for-like basis. available (Al Khaluf, Oman - the driven process. the higher the energy saving. cleaning and fewer membrane (less than 1 ppm). membrane life. world’s first commercial FO plant Possibility to consider replacements. Forward Osmosis began operation in 2010). 2 reduced pre-treatment. Extended membrane life (FO) Competitive advantages * site dependent - FO membrane life typically over RO. FO Membranes are chlorine twice that of the equivalent Significant further process tolerant allowing effective RO membrane. improvements to come. treatment for bio-fouling. Mature, well established High pressure - prone to Typically up to 30% more More than FO due to lower Poor removal and may Similar to FO but more Similar capital cost on a technology (Coalinga, fouling, hydraulic forces increase than FO. availability, higher energy costs, require additional costly post frequent cleaning and reduced like-for-like basis Reverse Osmosis California - the world’s first fouling - a key issue. Any degree of fouling, higher more chemical cleaning and treatment system. membrane life. commercial RO plant began RO Membranes are not chlorine than FO. membrane replacements. (RO) operation in1965). tolerant. Little further improvement likely. P1 - P2 > ∆ ∏ 1 2 ∆ ∏ ∆ ∏ P2 Source Osmotic Water Agent (Seawater (High or brackish Osmotic water) Pressure) P1 Forward Osmosis (FO) Reverse Osmosis (RO) A1 Khaluf, Oman 3 A1 Khaluf RO Plant AI Khaluf FO Plant25kW 5.0 4.5 Product 72 m3/d 42% reduction in /h) 4.0 3 25% Conversion 3 3.5 Feed 288 m /d 65 barg energy consumption 3.0 3 vs RO at A1 Khaluf 2.5 Brine 216 m /d 2.0 RO 1.5 1.0 FO Normalised Flow (m 0.5 0.0 Jan A12010 KhalufFeb 2010 MarFO 2010 PlantApr 2010 May 2010 Jun 2010 Jul 2010 19kWAug 2010 Sep 2010 Oct 2010 Nov 2010 Dec 2010 2kW Typical Year AI Khaluf RO Plant 47% Conversion Product in OA 100 m3/d Product 100 m3/d 5.0 65 barg 4.5 35% Conversion /h) 3 3 Membranes Installed New Membranes Installed 4.0 Feed 288 m /d 4 barg August 2009, 4.2 m 3/h 3.5 3 BrineCleaning 188 m Activity/d on New Membranes 3.0 Regeneration 2.5 FO 2.0 1.5 1.0 30% Decline in Output Over Just Five Months 0.5 Normalised Permeate Flow (m 0.0 Jan 2010 Feb 2010 Mar 2010 Apr 2010 May 2010 Jun 2010 Jul 2010 Aug 2010 Sep 2010 Oct 2010 Nov 2010 Dec 2010 Typical Year Technology Status Membrane Fouling Energy Consumption Operational Costs Boron Removal 5 Ease of Operation Capital Cost Innovative process solution now Extremely low inherent Typically up to 30% less than RO. Less than RO due to higher Inherently high removal, without Very similar to RO, but with less Similar capital cost on a fully operational & commercially fouling - low pressure, diffusion The more difficult the feedwater availability, less chemical the need for post treatment frequent cleaning and increased like-for-like basis. available (Al Khaluf, Oman - the driven process. the higher the energy saving. cleaning and fewer membrane (less than 1 ppm). membrane life. world’s first commercial FO plant Possibility to consider replacements. Forward Osmosis began operation in 2010). reduced pre-treatment. Extended membrane life (FO) Competitive advantages * site dependent - FO membrane life typically over RO. FO Membranes are chlorine twice that of the equivalent Significant further process tolerant allowing effective RO membrane. improvements to come. treatment for bio-fouling. P1 - P2 > ∆ ∏ Mature, well established High pressure - prone to Typically up to 30% more More than FO due to lower Poor removal and may Similar to FO but more = Similar capital cost on a technology (Coalinga, fouling, hydraulic forces increase than FO. availability, higher energy costs, require additional costly post frequent cleaning and reduced like-for-like basis Reverse Osmosis California - the world’s first fouling - a key issue. Any degree of fouling, higher more chemical cleaning and treatment system. membrane life. ∆ ∏ ∆ ∏ commercial RO plant began RO Membranes are not chlorine than FO. membrane replacements. (RO) P2 operation in1965). tolerant. Source Osmotic Water Agent Little further improvement likely. (Seawater (High or brackish Osmotic water) Pressure) P1 Forward Osmosis (FO) Reverse Osmosis (RO) 4 Process explained A1 Khaluf RO Plant At the heart of the Modern Water 25kW process is a recirculating “osmotic agent” Product 72 m3/d 42% reduction in system that transfers pure water from 25% Conversion Feed 288 m3/d energy consumption 65 barg the feedwater (eg seawater) to the Brine 216 m3/d vs RO at A1 Khaluf RO regeneration (permeate extraction) system. By linking two highly optimised systems, A1 Khaluf FO Plant 19kW the FO system and the regeneration 2kW system, significant benefits are achieved. 47% Conversion Product in OA 100 m3/d Product 100 m3/d 65 barg 35% Conversion In the first stage, feedwater is fed under Feed 288 m3/d 4 barg Brine 188 m3/d Regeneration low pressure to the forward osmosis FO membranes, which are highly resistant to fouling and are resistant to oxidising agents. The osmotic agent, on the other side of the membrane, draws fresh water from the 5 seawater due to a difference in osmotic Seawater or brackish pressure. This fresh water dilutes the water feed Reject from FO System osmotic agent. In the second stage, permeate is extracted from the system. The pure water is FO System removed from the dilute osmotic agent Diluted Concentrated which is regenerated (or concentrated) Osmotic Agent Osmotic Agent for reuse in the first stage. This can be achieved in a number of ways depending on the proprietary osmotic agent selected. Regeneration System Product Water To find out how we can help you please contact us on: + 44 (0)1483 696 000 Modern Water plc Bramley House, The Guildway Old Portsmouth Road Guildford Surrey GU3 1LR United Kingdom Other offices: Modern Water Modern Water Villa 10593 Unit 1701-2 Way No 4494 Westgate Tower Azaibah 1038 Nanjing Road W Muscat Shanghai 200041 Sultanate of Oman China + 968 244 918 33 + 86 21 6218 5183 Ext.140 www.modernwater.com DesalJan13.
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