the nano membrane toilet - sustainable sanitation alliance · the nano membrane toilet alison...

The Nano Membrane Toilet Alison Parker, Bruce Jefferson, Ewan

McAdam, Rob Dorey, Athanasios Kolios,

Sean Tyrrel, Phil Longhurst, Simon Bolton,

Glenn Leighton, Ben Martin, Paul Jones,

Richard Franceys, Chris Rose,

Elise Cartmell

#nanomembrane

User interface

• Accepts waste as a mixed stream

• For a single household

• Aspirational design to encourage household

purchase

• Odour free

Overall concept

Fibres run the length of

the module, the inside of

the fibres is known as the

lumen

A hollow volume

encircles the fibres,

known as the shell

Shell

input

Shell

output

Lumen

output

Conventional

pervaporation

Water vapour collection

Odours

Modular system gives

options

One size fits all?

Key challenges

Encapsulation using EHDA

nano-web

nano-membrane

fluid removal stage

nano-spinnerets

encapsulated

waste product

a) virgin materials

poly ε-caprolactone

b) reclaimed materials

(HDPE plastic bags)

Spray

HV

HEAT

Coalescence

nano-spinnerets

Multiple spray heads

Simultaneous operation

Formation of nano-web

Key questions

Maintenance

• 6 monthly visit by maintenance company to replace:

• Membrane cartridge

• Bead cartridge

• Polymer

Initial results

What is poo? A review of the medical literature

Chris Rose

Box Plot of Mass Wet (g/day)

Median = 128

25%-75%

= (106, 168)

Non-Outl ier Range

= (51, 250)

Outl iers

Extremes0

100

200

300

400

500

600

Ma

ss W

et

(g/d

ay)

Values from 116 studies

Box Plot of Mass Wet (g/day)

Median = 128

25%-75%

= (106, 168)

Non-Outl ier Range

= (51, 250)

Outl iers

Extremes0

100

200

300

400

500

600

Ma

ss W

et

(g/d

ay)

Mean faecal

wet mass

(g/cap/day)

Faecal mass

in response

to dietary

fibre intake

Values from 25 studies Fibre intake (g/day)

We

t m

ass (

g/d

ay)

Liquid generation

Variable Range

Volume l/cap/day 0.5-2.45

Water Content % 91.5-96

Urine generation rate (n=14)

Potential liquid inputs

Variable Quantity

Stool water l/cap/day (mean) 0.1

Urine l/cap/day 0.5-2.45

Anal cleansing l/wash 0.35-3

Pour flush toilet water l/flush 1-3

Estimated total water content

l/cap/day

1.95-8.55

Dry Matter Generation

Component of dry matter Quantity

Stool g/cap/day 4-102

Urine g/cap/day 50-75

Anal wiping g/cap/day 6*

Urinary wiping (women, presuming 6

urinations a day) g/cap/day

36*

Menstrual pads and flow g/cap/day 34*

Estimated total solid content

g/cap/day

130-253

*Data from Parker and Gallagher (1992)

Potential solid inputs

Data from 47 studies

Box Plot of Moisture %

Median = 74.6

25%-75%

= (72, 78)

Non-Outl ier Range

= (63, 86)

Outl iers

Extremes62

64

66

68

70

72

74

76

78

80

82

84

86

88

Mo

istu

re

%

Box Plot of Moisture %

Median = 74.6

25%-75%

= (72, 78)

Non-Outl ier Range

= (63, 86)

Outl iers

Extremes62

64

66

68

70

72

74

76

78

80

82

84

86

88

Mo

istu

re %

Mean water content

of faeces (%)

Faecal Composition

, Median

25%-75%

Min-Max

Outliers

ExtremesProtein Fat Carbohydrate Fibre

Faecal Composition

0

2

4

6

8

10

12

14

16

18

20

22

24

26g

/ca

p/d

ay

Chemical

Nature of

Faeces

Box Plot of COD mg/g

Median = 1380

25%-75%

= (567.43, 1450)

Non-Outl ier Range

= (101, 1671)

Outl iers

Extremes0

200

400

600

800

1000

1200

1400

1600

1800

CO

D m

g/g

Box Plot of COD mg/g

Median = 1380

25%-75%

= (567.43, 1450)

Non-Outl ier Range

= (101, 1671)

Outl iers

Extremes0

200

400

600

800

1000

1200

1400

1600

1800

CO

D m

g/g

Physical Nature

Lewis and Heaton (1997)

Bristol Stool Form

0

10

20

30

40

50

1 2 3 4 5 6 7

Bristol Stool Form Number

% s

too

l n

um

bn

er

ob

serv

ed

Iran (Adibi et al 2007)

UK (Heaton et al. 1991)

Bristol stool chart

Contact us

a.parker@cranfield.ac.uk

http://www.nanomembranetoilet.org

@nanomembrane