ZELDA
ZELDA
Which are the benefits of the ZELDA project?
What
What
does
does
ZELDA
ZELDA
stand
stand
for?
for?
The objective of the ZELDA project is to implement the
EDM
technology
coupled
with adesalination:
compound
recovery
eldaΖelda
means
means
ZeroZero
Liquid
Liquid
Discharge
Discharge
desalination:
brine
brine
stage
to
decrease
the
environmental
impact
caused
by
reatment
treatment
based
based
on aon
combination
a combination
of electro-separation
of electro-separation
current
management
strategies
in both, seawarocesses
processes
andbrine
and
valuable
valuable
compound
compound
recovery.
recovery.
ter and brackish water desalination plants, being the
final aim to reach a ZLD desalination process.
Main
Main
project
project
objective
objective
Seawater and brackish water desalination are currently
considered
one
the
best options
to face
up
he The
Life+Life+
Zelda
Zelda
project
project
aims
aims
toofdemonstrate
to demonstrate
and and
dissemidissemiwater
problem.
thesustainabilihigh
environatenate
the
technical
the scarcity
technical
feasibility
feasibility
andReducing
and
economical
economical
sustainabiliimpact
caused
by brine
management,
y ofty mental
decreasing
of decreasing
the the
overall
overall
environmental
environmental
impact
impact
ofwill
of
involve
clear
environmental
benefits
in
the
whole
esalination
desalination
systems
systems
for freshwater
for freshwater
production
production
by adoptby adoptarea. strategies
ng brine
ingEuropean
brine
management
management
strategies
based
based
on the
on the
use use
of of
The
new
membranes
developed
by
Fujifilm
present
lectrodialysis
electrodialysis
metathesis
metathesis
(EDM)
(EDM)
and and
valuable
valuable
compound
compound
high
permselectivity,
electrical
ecovery
recovery
processes,
processes,
withwith
the low
ﬁnal
the ﬁnal
aim aim
of reaching
ofresistance,
reaching
a zero
a low
zero
water
permeation
and
a
low
cost
compared
with
curquidliquid
discharge
discharge
(ZLD)(ZLD)
process.
process.
rent monovalent selective membranes commercially
available. Moreover, these novel membranes have
been developed specifically for high salinity applications.
The recovery of valuable compounds from brines will
not only make the ZELDA process more economically feasible, but will also allow to obtain commercial
salts from a waste. These solids are usually obtained
from mining activities, which cause a high environmental impact.
Zero
ZeroLiquid
LiquidDischarge
DischargeDesalination
Desalination
Project
Project
Coordinator
Coordinator
Partners
Partners
ABENGOA
ABENGOA
WATER
WATER
How will these benefits be estimated?
The results obtained during the pilot plant operations
will be analysed using standardized Life Cycle Analysis
(LCA) and Life Cycle Cost (LCC) procedures. Cradle-tograve approaches will be adopted and several impact
ZELDA
ZELDA
Project
Project
categories
will
be
analysed, including climate change,
water
depletion,
freshwater
eutrophication and toxicioject
Project
Ref.:Ref.:
LIFE12
LIFE12
ENV/ES/000901
ENV/ES/000901
ty, among others.
artStart
Date:
Date:
July 2013
July 2013 and economical impact of the new
The
environmental
ZELDA
technology
nalFinal
date:
date:
June
June
20172017will be compared to those from conventional
brine
management
strategies to demonstalTotal
Budget:
Budget:
2,301,553.00
2,301,553.00
€ €
trate that the technology is sustainable.
www.life-zelda.eu
www.life-zelda.eu
@zelda_project
@zelda_project ZeldaZelda
Project
Project
Pictures
Pictures
provided
provided
by CTM,
by CTM,
Fujiﬁlm
Fujiﬁlm
and Abengoa
and Abengoa
This This
research
research
has received
has received
funding
funding
fromfrom
the European
the European
Union’s
Union’s
Life +Life
Programme
+ Programme
under
under
the grant
the grant
Life12
Life12
ENV/ES/000901
ENV/ES/000901
The technology behind the ZELDA project?
In the last decade an innovative electrodialysis configuration, known as electrodialysis metathesis (EDM),
was developed to increase water recovery and to improve the performance of the conventional electrodialysis process.
In EDM configuration, the repeating unit comprises
one ordinary anion exchange membrane (A), one ordinary cation exchange membrane (C), one monovalent
selective anion exchange membrane (SA) and one monovalent selective cation exchange membrane (SC).
This unique configuration permits the separation of
the electrodialysis concentrate in two waste streams
of highly soluble salts: one contains sodium and anions, whereas the other contains chloride and cations.
As a result, the brine can be concentrated up to higher
concentrations without precipitation of salts, increasing the overall recovery of the desalination systems
and opening doors to valuable compound recovery.
REPEATING UNIT
Conc. 1:
Na+ + Anions
+
SC
-
ClNa+
SO42CO32-
Conc. 2:
Cl- + Ca ons
Diluate
C
-
A
+
+
+
+
+
+
+
+
+
+
Brine
Na+
Cl-
Mg2+
Ca2+
Diluted
NaCl
SA
+
+
+
+
+
+
+
+
+
+
SC
-
Na+
-
NaCl supply
Thanks to this new EDM configuration, the sparingly
soluble salts such as CaSO4, MgSO4 or CaCO3, are not
produced in neither of the concentrate streams.
The key point of the EDM
technology is to have
good monovalent selective membranes to allow
the proper separation of
monovalent ions from the
divalent ones, which are
the most susceptible to
form insoluble salts. Fujifilm will be in charge of developing and demonstrating
the good performance of novel monovalent selective
membranes to reach the ZELDA project objectives.
Where will this technology be tested?
To demonstrate the environmental benefits of
the innovative ZELDA brine management
process, the pilot plant will be implemented and operated in two different
sites from Spain: one seawater desalination plant and one brackish water
desalination plant.
The pilot plant will have the adequate dimensions and components, as
well as a simple and versatile design to
be easily scalable and adapted to treat
different brines.
How to make the process economically feasible
In order to reach a Zero Liquid Discharge (ZLD) desalination, and also to make the brine management more
economically feasible, the EDM process will be coupled to a second stage aimed to recover valuable compounds (Mg(OH)2, Na2SO4, NaCl, etc).
Reangels
EDM
concentrate
Precipitation
process
Valuable solids
There are a number of valorization options for different salts depending on the origin of the brine. Considering the two EDM concentrate compositions when
treating the brines of interest, CTM will theoretically
evaluate several scenarios using specific speciation
software. The best precipitation routes will be validated at bench scale and from the results obtained the
most profitable recovery strategy will be adopted.
Abengoa, with a broad experience in desalination processes, will be in charge of
designing and constructing
a pilot plant to treat all the
effluents from the EDM
stage, leading to a complete and integrated system.
Coupling the EDM stage
with the recovery of valuable compounds will lead
to a brine management
process which, not only is
technically feasible, but its
economics will be also sustainable.