modern water

Bringing new technology to the water industry

Forward Osmosis – The Story So Far Proven Process & Commercial Reality

2nd Annual Power and Desalination Summit Riyadh 17-18 March 2013

Bringing new technology to the water industry 2

Outline

Forward Osmosis – The Story So Far Proven Process & Commercial Reality

• Introduction to Modern Water and the FO Process

• Process & commercial development from research project to operational plants

• Gibraltar FO

• Al Khaluf FO (RO vs FO)

• Al Najdah

• What next for FO?

Modern Water - Introduction

Modern Water’s mission is: to source, develop and deploy technology-based solutions

to meet the growing demand for the economic availability of fresh water and treatment of waste water

• Founded – 2006 to exploit portfolio of water related technologies

• IPO – London, June 2007

• 89 granted patents with 58 applications pending – of which 53 granted patents in 5 main groups relate to membrane processes

• Strong R&D – links with Universities & Research Organisations – UK, Europe, Australia, Japan, USA

• R&D Expenditure in Membrane Processes £500,000/annum – excluding overheads and staff costs

• Highly experienced team which has delivered and managed large

scale desalination projects around the world



Forward Osmosis

∆π

∆π

Source Water

(Seawater or

Brackish

Water)

Osmotic

Agent

(High Osmotic

Pressure) P1

P2

P2-P1 > ∆π

Reverse Osmosis

(RO)Forward Osmosis

(FO)


What use is FO?

• Operates at low pressure, typically 0 – 3 barg

• Can concentrate one stream with a lower osmotic pressure using another of higher osmotic pressure

• Dilute a more concentrated stream with a lower concentrated stream

• Particular advantages with difficult feed waters

• Applications: • Desalination (MWG)

• Water substitution (MWG)

• Thermal desalination feedwater softening (MWG)

• Enhanced oil recovery (MWG)

• Fracture water (MWG)

• Emergency drinks from brackish or sea water

• Power generation (MWG)

1. Source HTI

2. Source Statkraft

1

2


Forward Osmosis

Feed water in

Draw solution in Diluted draw solution out

Concentrated feed

water out

Forward Osmosis

System


Forward Osmosis Desalination

Forward Osmosis System

Regeneration Membranes

FeedwaterReject from forward

osmosis system

Product Water

Concentrated

Osmotic Agent

Diluted

Osmotic Agent


FO Desalination – Process challenges

• The selection of the osmotic agent / draw solution, which by

necessity must be non toxic

• Maintaining a constant osmotic pressure for the concentrated

osmotic agent

• Managing the contamination of the osmotic agent with salts from

the feed solution

• Minimising back diffusion of the osmotic agent to the feed solution

• A robust forward osmosis membrane that can adequately deal with

flow on both sides

• Operating on a continuous and economic basis

• Pre-treatment considerations

Advantages of FO Desalination


9

Forward Osmosis (FO) Reverse Osmosis (RO) Technology Status Innovative process solution now fully operational & commercially

available . A proven, robust and reliable membrane process. 3 full-scale

plants now operating (Al Khaluf, Oman - the world’s first commercial

FO plant began operation in 2010).

Competitive advantages over RO.

Mature, well established technology (Coalinga, California - the

world’s first commercial RO plant began operation in1965).

Little further improvement likely.

Membrane Fouling Extremely low inherent fouling - low pressure, diffusion driven

process.

Possibility to consider reduced pre-treatment (site dependent).

FO Membranes are chlorine tolerant allowing effective treatment

for bio-fouling.

High pressure - prone to fouling, hydraulic forces increase fouling

- a key issue.

RO Membranes are not chlorine tolerant.

Energy Consumption Typically up to 30% less than RO.

The more difficult the feedwater the higher the energy saving.

Typically up to 30% more than FO.

Any degree of fouling, higher than FO.

Operational Costs Less than RO due to higher availability, less chemical cleaning and

fewer membrane replacements.

Extended membrane life - FO membrane life typically twice that

of the equivalent RO membrane. Reduced life-

time costs.

More than FO due to lower availability, higher energy costs,

more chemical cleaning and membrane replacements.

Boron Removal Inherently high removal, without the need for post treatment

(less than 1 ppm).

Poor removal and may require additional costly post treatment

system.

Ease of Operation Very similar to RO, but with less frequent cleaning and increased

membrane life.

Similar to FO but more frequent cleaning and reduced membrane

life

Capital Cost Similar capital cost on a like-for-like basis. Similar capital cost on a like-for-like basis.


Competitive

Tendering

Tender

Award

2011

2012

Production

Facility 2010

Demonstration

Facility 2009

Laboratory

Work 2008

2007

FO Desalination Development


Demonstration Facility

• Located in Gibraltar

• Commissioned September 2008

• Fabricated in UK and shipped

• Housed in a 20’ ISO shipping

container

• Located adjacent to an existing

SWRO facility


Demonstration Facility

• Challenging location

• 50m inside a damp cave

• Open seawater intake

• Common pre-treatment with conventional SWRO plant (SDI15, 3 – 4)

• Product water into public supply 1 May 2009

• Independently tested

• TDS < 200 mg/l

• Boron < 0.6 mg/l

• Plant used for development activities

• Output doubled over test period

• 35m3/d

• Automatic operation, 24 hours a day

• Membranes never cleaned!

• Currently testing new MWFO-4G membranes (March 2013)


Production Facility

• Located in Al Khaluf, Oman

• Commissioned November 2009

• Fabricated in UK

• Housed in a 40’ High-cube ISO

shipping container

• Design capacity 100m3/d

• Shares a common pre-treatment

with a SWRO plant

Al Khaluf


Al Khaluf Project - Summary

• Fully operational since November 2009 – water into public supply

• Common pre-treatment with conventional plant

• Shallow open sea water intake (39,000 mg/l)

• Single dual media filter (velocity 16 – 25 m/h)

• SDI5 typically 5 after cartridge filters (immeasurable elsewhere)

• FO System • Cartridge filtration – 10 micron nominal

• 35% - 38% recovery (design 30%)

• Antiscalant dosing

• Periodic low dose chlorination

• Membranes never chemically cleaned in over 30 months


Al Khaluf Project - Summary

• Operating personnel same as RO • MW trained local Omani’s to operate Al Khaluf

plant

• Product water meets requirements of Omani Standard No. 8/2006 with post-treatment, untreated product:

• Total dissolved solids < 200 mg/l

• Boron 0.6 – 0.8 mg/l

• Visited by WDR in November 2010 and subsequently given a WDR Technology Rating of 8.9 – the joint highest


Al Khaluf - Normalised Flow

FO Plant

RO Plant

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

Jan-2010 Feb-2010 Mar-2010 Apr-2010 May-2010 Jun-2010 Jul-2010 Aug-2010 Sep-2010 Oct-2010 Nov-2010 Dec-2010

No

rmal

ised

Per

mea

te F

low

(m

3/h

)

New Membranes Installed

30% Decline in Output Over Just Five Months

Cleaning Activity on New Membranes

Membranes Installed

August 2009, 4.2 m3/h

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

Jan-2010 Feb-2010 Mar-2010 Apr-2010 May-2010 Jun-2010 Jul-2010 Aug-2010 Sep-2010 Oct-2010 Nov-2010 Dec-2010

FO

No

rmal

ised

Flo

w (

m3/

h)


Al Khaluf - Energy Consumption

RO

FOD

Overall energy saving comparison at Al Khaluf = 42% reduction Note energy consumption and savings are feedwater and site specific

25% Conversion

65 bargFeed 288 m

3/d

Brine 216 m3/d

Product 72 m3/d

25 kW

35% Conversion

4 bargFeed 288 m

3/d

Brine 188 m3/d

Product in OA 100 m3/d

2 kW

47% Conversion

65 bargProduct 100 m

3/d

19 kW


Production Facility – Tendered Project

• Located in Al Najdah, Oman

• Commissioned July 2012

• Fabricated in Oman


shipping container

• Installed capacity 220m3/d

• Shares a common pre-treatment

with a SWRO plant

Al Najdah


Al Najdah Project - Summary

• In June 2011 Modern Water was awarded a contract to build a 200m3/d (original design capacity) facility located in the same region as Al Khaluf

• Evaluation based on: • Technical factors

• Economic factors (including through life cost)

• Fully commercial application of forward osmosis

• Incorporating fabrication in Oman

• Project complete • O&M contract started September 2012


Al Najdah Project

• Feedwater

• Borehole: TDS 45,000 – 60,000 mg/l

• SDI (15 mins) after filtration: 2 – 3

• Sulphuric acid plus antiscalant

• Boron: 7 mg/l

• Design recovery: 35%

• Product water (pre post-treatment)

• TDS: 250 – 300 mg/l

• Boron: 0.6 – 0.8 mg/l


Demonstration Facility – FO ECS

• FO Evaporative Cooling System

(FO ECS) – provision of low-cost

make-up water.

• Originally located in Sohar,

Oman 2011-2012

• Currently being shipped to

Kuwait for new client

• Fabricated in UK


shipping container

Kuwait

Sohar


Conventional Cooling Tower

Recirculation Pumps

Heat Exchanger

Cooling Tower

Evaporation

Drift Loss

Blowdown

Make-up Chiller Plant


Seawater or brackish water feed Reject from manipulated osmosis system

Manipulated Osmosis System

Heat Exchangers

Cooling Tower

Evaporation

Drift Loss

Recirculated Osmotic Agent

Concentrated Osmotic

Agent

Blowdown System

Blowdown

FO Cooling Tower System

Cooling System

incorporating FO make-up (cooling water as osmotic agent)

Make-up via

forward

osmosis


FO Cooling Tower System

Seawater or brackish water feed Reject from manipulated osmosis system

Manipulated Osmosis System

Heat Exchangers

Cooling Tower

Evaporation

Drift Loss

Recirculated Osmotic Agent

Concentrated Osmotic

Agent

Blowdown System

Blowdown

Cooling System

incorporating FO make-up (cooling water as osmotic agent)

Incorporating MW

Blowdown Recovery

System

Make-up via

forward

osmosis


FO Evaporative Cooling System

• Demonstration / test plant housed in 20’ container

• Extensively tested at Sohar Industrial Port, Oman

• Requires a source of raw water (seawater, brackish water, TSE), drain, power and heat load

• Membrane pre-treatment

• Multi-media pilot filter columns

• Air scour

• Backwash

• Flocculant dosing

• Antiscalant

• Packaged cooling tower

• Heat exchanger

• Membrane Support Systems

• Blowdown recovery system


Power Comparison – Make up Water

0

1

2

3

4

5

6

7

8

0 10,000 20,000 30,000 40,000 50,000

Feed Water TDS (mg/l)

kW

h/m

3

RO with ERT

RO no ERT

Manipulated Osmosis

Manipulated Osmosis (OA recovery)

Assumptions Temperature 25ºC Maximum conversion on MO limited to 30% (very conservative)

Pre-treatment requirements the same for MO and RO Conversion for RO, 80% - 41% depending on feed TDS

Pump overall efficiency 70% Tower concentration ratio 5

Energy recovery efficiency 70%


Power and Chemical Comparison

0

0.1

0.2

0.3

0.4

0.5

0.6

0 10,000 20,000 30,000 40,000 50,000

Feed TDS (mg/l)

Co

st

US

$/m

3

RO Power Cost

RO Power Cost with ERT

MO Power & OA Cost

Assumptions Temperature 25ºC Maximum conversion on MO limited to 30% (very conservative)

Pre-treatment requirements the same for MO and RO Conversion for RO, 80% - 41% depending on feed TDS

Pump overall efficiency 70% Tower concentration ratio 5

Energy recovery efficiency 70% Power US$ 0.075 / kWh

Osmotic agent US$ 75 / tonne


Osmotic Agent / Cooling Water (1)

• Osmotic agent low cost, readily available and non toxic

• Osmotic agent concentration optimised for raw water feed to minimise losses and maximise vapour pressure

• Material compatibility – real time and coupon testing

• 304 ss, 316 ss, Cu alloys little or no metal loss

• Carbon steel some metal loss, greatly reduced by corrosion inhibitor (phosphonates & carboxylic acid)

• Speciality additive work ongoing with chemical supplier


Osmotic Agent / Cooling Water (2)

• Biological testing

• Legionella killed in osmotic

agent – MIC 3.6 bar osmotic

pressure equivalent

• Inherent biocide affect

• Pseudomonas not inhibited

• Extensive laboratory testing

• Blowdown system

• ‘Loose’ membrane based

• Retains osmotic agent and other

chemical additives

• Removes contaminants

0

200

400

600

800

1000

1200

0 0.2 0.3 0.6 1.1 2 3.6 7 14.1

Equivalent Osmotic Pressure (bar)

Av

era

ge

co

un

ts o

f L

p (

CF

U/m

l n

=3

)

24 h

48 h

72 h

Nicoll P, Thompson N, Gray V ‘Forward Osmosis Applied to Evaporative Cooling Make-up Water’,

Cooling Technology Institute Journal, Volume 33, No. 2, Summer 2012


Blowdown System

• Patented system allowing removal of ionic

contaminants and retention of high molecular

weight chemicals

• Cooling water chemical additives are partially

recycled

• Significant chemical savings

• Environmental discharges reduced

• Osmotic agent is recycled


Cooling Water Properties

• Generally non corrosive and compatible with heat transfer

surfaces

• Vapour pressure dependent on feedwater source

• Seawater feed – estimate 5% increase in tower area

• TSE feed – no increase in tower area

• Thermal conductivity higher than water

• Improved heat transfer

• Density dependent on feed water source

• Seawater feed – density ≈ 1,160 kg/m3

• TSE feed – density ≈ 1,020 kg/m3


Evaporative Cooling – FO Advantages

• Same ‘platform’ technology as desalination application – an

ideal FO process

• Can utilise a wide range of feedwaters

• Significantly reduced power consumption compared with

reverse osmosis (88% - 40%, typically 50%)

• Reduced CAPEX, compared to RO

• Extensive use of low cost plastic materials

• Low fouling propensity of forward osmosis process

• Cooling water additives are retained by the blowdown

recovery system

• Can be retrofitted to existing installations


What next for FO?

Forward Osmosis

Future Developments

Modern Water – What next for FO?

• FO Desalination • Increased project scale

• Membrane developments – MW FO 4th generation membranes

• Submerged FO

• FO Application Demonstration/Trials • Thermal desalination (MSF) feedwater softening application

• Fracture Water application

• New FO Application Developments • Industrial concentration and/or dilution process applications

• Salt concentration applications

• Hydro Osmotic Power

• FO Process Development • Membrane developments for other applications outside FO desalination

• Development of enhanced osmotic agent/draw solutions

• New Markets • China/USA



Membrane Development

• Current FO membrane is third generation

(MWFO3.5)

• Fourth generation (MWFO4) with

significant improved permeability,

laboratory tested and prototype testing

commencing March 2013 in Gibraltar

• Clear roadmap for further development in

place

• Cambridge laboratory facilities include flat

sheet and hollow fibre forward osmosis

test rigs


Future Developments - Submerged FO

• Utilises existing membrane bio-rector experience

• Air sparging etc

• Removes significant requirements for seawater pre-

treatment

• Chemicals and energy

• Applicable to other Modern Water applications

• Enhanced oil recovery (EOR)

• Cooling towers (ECS)

• Can be installed on or offshore

• Innovative solution

• The advantages of forward osmosis are immediately

apparent


Conclusions

• Forward osmosis now a proven technology at industrial scale with fully commercial plants now operating

• Robust process with proven resistance to membrane fouling

• Highly significant OPEX reductions compared to RO with similar CAPEX on a like for like basis

• Numerous further potential applications in development

• Significant process improvements still to come


Find out more at

www.modernwater.co.uk


Further Reading

• Cath T, Childress A, and Elimelech M ‘Forward osmosis: Principles,

applications, and recent developments’ Journal of Membrane Science, May

2006.

• Thompson N & Nicoll P ‘Forward Osmosis Desalination: A Commercial Reality’,

Proceedings IDA World Congress, Perth, Western Australia, September 2011.

• Nicoll P, Thompson N, Bedford M ‘Manipulated Osmosis Applied To

Evaporative Cooling Make-Up Water – Revolutionary Technology’, Proceedings

IDA World Congress, Perth, Western Australia, September 2011.

• Nicoll P, ‘Forward Osmosis Applied to Desalination and Evaporative Cooling

Make-up Water’, International Water Conference, Orlando, USA, November

2011.

• Nicoll P, Thompson N, Gray V ‘Forward Osmosis Applied to Evaporative

Cooling Make-up Water’, Cooling Technology Institute, February 2012.

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