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www.cranfield.ac.uk

Membrane Technologies for Decentralised Sanitation, Energy Recovery and Anaerobic digestion.

Christopher Davey

17th October 2018

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Outline

• About Cranfield Water Science Institute

• Membranes at Cranfield

• Our Facilities

• Specific project examples

1.) Nanomembrane toilet

2.) Reverse Electrodialysis

3.) Membrane Contactors for Ammonia

Recovery

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Cranfield Water Science Institute

Sewage works of the future

Water for food Water governance and asset

management

Water and sanitation in low income countries

Membrane processes

Catchment management

Drinking water treatment

Bioprocessing and environmental technology

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Membranes at Cranfield

Marc Pidou

Bruce Jefferson

Ewan McAdam

Simon Judd

Chris Davey

Mehrez Hermassi

>10 PhD students: Sam Houlker; Salvatore Bavarella; Edwina Mercer; Kanming Wang; Farhad Kamranvand; Dan Golea; Anna Hulme; Kostas Vasilakos

Permanent members of staff

PDRA

Luca Alibardi

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Materials characterisation Process diagnostics Scaled testing

Permeability assessment -Crossflow -Dead-end

Surface free energy for cylindrical and flat-sheet materials

Gas-mixing manifold for determining gas phase flux of material

Chemical gradient potential

Optical coherence tomography

Real-time particle tracking

On-site demonstration (applicability to real environment)

Pilot-hall. More representative scale of economic feasibility on real wastewater

Import of alternative feed-water for testing new applications

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National water and wastewater experimental facility

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Compliance

Membranes at Cranfield

1 Energy

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Resource recovery

3 Water recycling

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Membranes at Cranfield

Proof of Concept Process Optimisation Scaled Testing

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1.) Nanomembrane toilet

http://www.iwa-network.org/press/18-winners-at-the-12th-iwa-project-innovation-awards/

http://www.nanomembranetoilet.org/meettheteam.php

‘to achieve in-house piped water supply and sewerage connection with partial treatment of sewage would require investment of US$136.5 billion per year’ - World Health Organisation, 2004

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True decentralisation of infrastructure

1.) Nanomembrane toilet

0

20

40

60

80

100

120

140

160

0.1 1 10 100

y-Se

ttlin

g ve

loci

ty (

mm

/s)

Sauter Mean Diameter (mm)

PS01 (BSS5)PS02 (BSS4)PS03 (BSS4)PS04 (BSS6)PS05 (BSS3)PS06 (BSS2)PS07 (BSS6)PS08 (BSS4)PS09 (BSS6)PS10 (BSS4)PS11 (BSS6)PS12 (BSS4)

0

500

1000

1500

0 20 40 60 80 100

Pe

rme

ate

CO

D c

on

cen

trat

ion

(m

g l-1

)

Time since permeation began (h)

Faecally contaminated urine

Real urine

ISO Standard

Sedimentation PASSIVE SEPARATION: Can gravity

provide initial upstream solid/liquid separation?

Membrane DISCHARGE STANDARD: Can thermally driven membrane technology provide single stage separation for faecally contaminated urine?

Screw delivery SLUDGE TRANSPORT: Can we achieve solid/liquid separation, faecal sludge transport and dewatering in a single stage?

Combustion SCALE DOWN: Can we reverse engineer combustion to match application scale?

Urine

Permeate Permeate

Faecally contaminated

urine

Mercer et. al., Environ. Sci.: Water

Res. Technol., 2016, 2, 953-964

Kamranvand et. al., Sep. Sci. Technol.,

2018, 53, 9, 1372–1382

Jurado et. al., Energy Convers. Manag., 2018,

163, 9, 507–524

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1.) Water Recovery - Membrane Distillation

Urine

Permeate Permeate

Faecally contaminated urine

Kamranvand et. al., Sep. Sci. Technol., 2018, 53, 9, 1372–1382

Proof of Concept Process Optimisation Scaled Testing

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Concentrate Management and Energy Recovery

2.) Reverse Electrodialysis

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50

100

150

200

250

300

0 0.05 0.1 0.15 0.2

ΔG

(J k

g-1

)

Δ Concentration (M)

> 80 % of Energy

MD Permeate ~ 0.5 mS cm-1 Drinking Water ~ 5 – 50 mS cm-1

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2.) Reverse Electrodialysis

Proof of Concept Process Optimisation Scaled Testing

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Anaerobic Digestion – Ammonia Problematic

3.) Membrane Contactors for Ammonia Recovery

58% of land in England is designated an NVZ, limiting Nitrogen application

Nutrient value £4-6 tonne-1; disposal cost £10 tonne-1

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3.) Membrane Contactors for Ammonia Recovery

Ammonium sulfate crystals formed

3 Crystals collected downstream

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Nucleation

Nucleation at the membrane

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Membrane

Crystal rotation observed due to applied torque

Crystals growing on membrane

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3.) Membrane Contactors for Ammonia Recovery

Ammonium sulfate crystals formed

Proof of Concept Process Optimisation Scaled Testing

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Conclusions

• Research focuses on process engineering, tailor and adapting membrane processes to unique

applications.

• Capabilities for taking technology from proof of concept to full scale testing.

• Examples:

• Membrane distillation for water recovery from faecally contaminated urine.

• Reverse Electrodialysis for simultaneous concentrate management and energy recovery.

• Membrane Contactors for Ammonia Recovery.

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Acknowlegdements

• Dr. Ewan McAdam

• Nanomembrane toilet: Farhad Kamranvand, Peiji Liu, Edwina Mercer

• Ammonia Recovery: Dr. Mehrez Hermassi, Erwan Allard, Mallek Amine