WAIV for brine management - EDS-may 09-7.5.09

8/9/2019 WAIV for brine management - EDS-may 09-7.5.09

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Katzir EDS May 2009 1

WAIV- Wind Aided Intensified eVaporation forvolume reduction of desalination brine andgenerating mineral byproducts.

Lilach Katzir and Jack Gilron

Zuckerberg Institute for Water ResearchBen-Gurion University of the Negev

Beer-Sheva/Sede-Boker, Israel


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Overview

Introduction A brief review on concentrate disposal options

Presentation of WAIV concept Result from the WAIV pilot studies at Sede-

Boker

Different feeds-BWRO ,BWRO-ED Large scale plant Economic projections Conclusions

Future work


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Brine disposal options

Surface - to sea, lakes and rivers Sewer system

Land applications - including irrigation ofhalophytic crops

Deep well injection

Zero liquid discharge

Evaporation ponds

Introduction


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Evaporation ponds - challenges

Evaporation ponds were used for 6% ofRO installations before 1993, and just 2%since then

Why? Large land area required.

increased environmental impact increased costs both for land

purchase and double lining

Efficiency drops with pond area

Introduction

Adapted From M. Mickley, USBR, 2001


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WAIV Concept

Involves increasingthe evaporativecapacity per

footprint area byclose packingvertically mounted

and wet surfaces.

Introduction

Main

wind

direction


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WAIV-driving forces

The temperaturegradient drive theevaporation heattransfer

The vapor pressuregradient drives theevaporation masstransfer

Introduction


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WAIV Concept evaporation rate andwind

Evaporation from body of water as functionof wind velocity and mass driving force

E [mm/day]- evaporation rate

e [mbar]- vapor pressure

ur [m/s]- wind velocity

Ne [mbar-1]- Constant from the evaporative mass transfercoefficient

Introduction

*aWreeeuNE



Results from the WAIV pilot studies inSede- Boker

BWRO brines- 75% recovery

Brine from BWRO-ED hybrid (~10% TDS)

Methods



BWRO-75% recovery

Feedwater was treated in a batch mode

Four BWRO elements (ESPA-2)

Flux of 20 L/m2-h to reach 75% recovery

1600 L well-water were treated to produce400 L of concentrate

Methods



Volume Concentration Factor vs. RelativeHumidity over the solution-88% recovery

Results

With BWRO recovery of 88% we can get up to VCF of 50and still be able to evaporate.

WATER VCF vs. R.H OVER THE SOLUTION

0

20

40

60

80

100

120

0 10 20 30 40 50 60

VCF OF H20

R.H

O

VER

THESO

LUTION

vcf 50 R.H in sde-boker



VCFnom vs. R.H, driving force and evaporationrate [mm/d] based on WAIV footprint

Results

Clear correlation between the relative humidity difference (p/po- RHair) tothe evaporation rate and the driving force.

VCF nominal VS. R.H

0

20

40

60

80

100

120

0 5 10 15 20 25VCF nom

%P/P

0,R.H

,Emm/d

0

1

2

3

4

5

6

drivingforce

mbarH

2O

p/p0- solution R.H.- airevaporation rate [mm/day] driving force



Magnesium enrichment by WAIV

Results

BWRO - 75% recovery

0

1

2

3

4

5

6

7

Desal Conc After WAIV

Mg/Ca,

mg/mg

10*Mg/Na

,mg/mg

Mg/Na

Mg/Ca


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Near ZLD BW desalination process based on ED-RO-Crystallizer and WAIV-recovery 97-98%

Methods

Korngold et al., Desal, 172(2005),63. Gilron et al., Euromed, 2008.


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Evaporation rate TDS=10%

Results

The cumulative volume evaporated from BWRO-ED ishigher than evaporation pond by factor of 11.5

Cumulative volume evaporated vs. time

y = 4.67x + 14.47

R2 = 0.91

y = 68.12x - 31.19

R2

= 0.99

y = 40.94x + 142.40

R2 = 1.00

0

100

200

300

400

500

600

700

800

900

0 2 4 6 8 10 12 14 16 18Time from start of run [day]

cumulative

volume

ED concentrat pan evaporation rate


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SEM and XRD analysis from BWRO-EDbrine

Results

shows that the mineralsthat precipitate are Halite

(NaCl) and Gypsum(CaSO4*2H2O)

O, 9.69

Na, 34.32Cl, 51

Ca, 2

S, 1.84

Mg, 1.14


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Large Pilot plant-Lesico Cleantech

The plant is located in North-America in asemiarid zone.

Net WAIV footprint: 8*10-3 hectare footprint

Total fabric area: 0.16 hectare fabric

This WAIV unit is evaporating ~730 m3/day perhectare of WAIV unit footprint.

Evaporation from evaporation pond is ~35

m3/day per hectare

Results


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Large Pilot plant (Lesico Cleantech)

Results


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Large Pilot plant

Results

Cumulative volume WAIV vs. Pan Evap. / footprint [L/m2]

0

5001000

1500

2000

2500

3000

13/02/09 23/02/09 06/03/09 17/03/09 28/03/09 07/04/09

[

L/M2]

Accum. WAIV evap. /footprint Acum. Pan evap. / footprint

Amount evaporated at WAIV un it vs . pan evap oration

[L /m2-day]

0

100

200

300

13/02/09 24/02/09 08/03/09 20/03/09 01/04/09 12/04/09

[L/m2-day]

Footprint WAIV unit evaporation Footpint pan evaporation


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Economic projections- Base case forcomparison

Mashabe Sadeh well-water

RO (used BW30-LE) 88% recovery

Electricity costs 0.072 /kWh

Annual capital charge rate- 8.00%

RO production costs (incl. pretret)- 0.302 /m3

product

Brine to evaporation ponds 1.4 /m3


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Economic projections- Base case forcomparison

Mashabe Sadeh well-water

RO (used BW30-LE) 88% recovery

BWRO-ED hybrid 97-98% recovery

Brine removal costs-by evaporationponds

1.40 /m3 brine

Brine removal costs- byWAIV 1.05

/m3 brine

(based on economic data from P. Glueckstern and E. Ramon)


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Economics (100 m3/h feed, 98% recovery)

0

50000

100000

150000

200000

250000

300000

350000

1 2 3 4 5

Options

Annualc

osts,

Euro/m3

RO ED Brine Total

Base75%

RO+ED 83%RO+ED

88%RO+ED

RO-APS-RO


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Conclusions

Efficiency of the evaporation rates from WAIV

can reach 50% - 90% relative to open ponds

It is feasible to get an enrichment of the

magnesium salts for RO and ED brine

WAIV increased ED brines from TDS of 10% to29.2% and enhanced MgCl2 content for

potential recovery

Conclusions


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Conclusions

Evaporation rates tend to drop after brine

reaches TDS of 15% due to a decrease vaporpressure

There is a clear correlation between vapor

pressure, driving force and evaporation rate This process is more economical than

conventional RO (88%) and brine disposal by20,000 40,000 /y for a plant producing 2400

m3

/day.

Conclisions


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Acknowledgements

Lesico Cleantech and Mr. E. Ramon for information on

large WAIV pilot Dr. Rosa Fainshtain for analytical support. ZIWR technical staff - Mr. Isaac Lutvak, Michael

Waisman, Nisan and Naftali Daltrophe for support onWAIV unit.

Mr. Yuval Shani and Dr. Naftali Lazarovitch-meteorological and data equipment support.

Financial support was provided by BMBF-MOS projectgrant WT 0504, "Near-ZLD Strategy for OptimalManagement of Inland Brackish Water Desalination",

MEDINA (MEmbrane Desalination an INtegratedApproach) project (EU FP6 grant #036997)

Bauer and Rosoff Prize for Excellence in Research.


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Future work

WAIV operation on BWRO concentrate with 88%

recovery containing antiscalant

WAIV operation on BWRO-ED concentrate withinitial TDS of 10%

Goal is to reach Mg concentration>8%.


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WAIV for brine management - EDS-may 09-7.5.09