Greywater Recycling: Field Experience
363
4.1 Nanofiltration
NF is a membrane separation process with an effective pore size of the membrane
of several nanometers (see Fig. 2).
c
o '"
:c ~
0: ...
... 0
0: ...
~Q.
en
CI>
i.ii
. .
~ ...
0:
Q.
to 4
lion. I
~
)lm 10-3
10.2
10.1
MnkroIon
Molecule
Molecule
Iveast
[IlIdig61
10 1
MirroPartiel
~
~
ISandl
ell I
lA-Carboni
I Pollen I
10 2
10 3
Maq-oParticle
Fig. 2. Membrane Processes: Separation Characteristics
The main characteristics of this process are:
• Removal of bacteria and virus
• Removal of color
• Reduction of organic contamination
• Partial softening and desalination.
4.2 UV Disinfection and Chlorination
As a second process for inactivation of pathogenic germs, UV Disinfection is
applied. Further chlorination is done to prevent microbiological regrowth during
storage of recycled water.
5 Greywater Recycling: Process Scheme
Essential for greywater recycling is a dual collection system to avoid crosscontamination with fecal wastewater from toilets. Kitchen wastewater is also not