Removal of Arsenic from Removal of Arsenic from Drinking Water using Hybrid Drinking Water using Hybrid

Ion Exchangers or HIX : A Ion Exchangers or HIX : A Prudent approach for Rural Prudent approach for Rural

Water UtilitiesWater Utilities

Presented Presented by by

VEETech, P.C. VEETech, P.C. 942 Millbrook Avenue, STE # 6942 Millbrook Avenue, STE # 6

Aiken, SC Aiken, SC

Effect of Arsenic in Drinking Effect of Arsenic in Drinking WaterWater

SourcesSources Natural Geochemical contamination through soil Natural Geochemical contamination through soil

leachingleaching Inorganic arsenic, which occurs as As(III) or As(V) Inorganic arsenic, which occurs as As(III) or As(V)

in drinking water, presents great threat to public in drinking water, presents great threat to public healthhealth

Exposure can causeExposure can cause Thickening and decoloration of skinThickening and decoloration of skin Nausea and DiarrheaNausea and Diarrhea Decreased production of blood vesselsDecreased production of blood vessels Skin cancer and tumors of the bladder, kidney, Skin cancer and tumors of the bladder, kidney,

liver and lungliver and lung

Illustration of a typical three-step procedure to Illustration of a typical three-step procedure to disperse both crystalline and amorphous HFO disperse both crystalline and amorphous HFO

nanoparticles inside the spherical polymer nanoparticles inside the spherical polymer beads to form Hybrid Ion Exchangers or HIXbeads to form Hybrid Ion Exchangers or HIX

Desirable Attributes of Fixed Desirable Attributes of Fixed Bed Sorbents (e.g., HIX) for Bed Sorbents (e.g., HIX) for

Arsenic RemovalArsenic Removal

Excellent Mechanical Strength and Attrition Excellent Mechanical Strength and Attrition Resistance Resistance Selective towards both As(III) and As(V)Selective towards both As(III) and As(V) Does not require pre or post treatment (e.g., pH)Does not require pre or post treatment (e.g., pH)

Desirable Attributes (contd…)Desirable Attributes (contd…)

Does not alter the electrolytic quality of treated waterDoes not alter the electrolytic quality of treated water Does not generate fines or pressure drops during long Does not generate fines or pressure drops during long

term column operationterm column operation Efficiency is not affected by the presence of high Efficiency is not affected by the presence of high

concentrations of silica, phosphate, or sulfate in water concentrations of silica, phosphate, or sulfate in water Can treat up to 40,000 bed volumes (BV) of water/cycleCan treat up to 40,000 bed volumes (BV) of water/cycle Can be regenerated up to 20 to 30 cycles of operationCan be regenerated up to 20 to 30 cycles of operation Can remove multiple contaminants such as Ra, U, and Can remove multiple contaminants such as Ra, U, and

perchlorate along with Arsenicperchlorate along with Arsenic

Typical Influent / Effluent TDS vs. Typical Influent / Effluent TDS vs. Bed Volume Bed Volume

Typical Influent / Effluent pH vs. Typical Influent / Effluent pH vs. Bed Volume Bed Volume

Typical Bench Scale Study: Typical Bench Scale Study: Arsenic(III) Effluent History for a Arsenic(III) Effluent History for a

column runcolumn run

0 1500 3000 4500 6000 7500 9000 10500 12000 13500 15000

Bed Volum es

0

10

20

30

40

50

60

70

80

90

100

Ars

enic

, g

/L

Experimental ParametersEm pty Bed C ontact T im e = 4 .5 m in

Influent SolutionAs(III) = 100 g/LSO 42- = 170 m g/L

C l- = 90 m g/LH C O 3- = 100 m g/LpH = 6 .2

M axim um C ontam inant Level (M C L)

Typical Bench Scale Study: Typical Bench Scale Study: Comparison of Arsenic and Silica Comparison of Arsenic and Silica

BreakthroughBreakthrough

0 1500 3000 4500 6000

B ed V olume

0.00

0.15

0.30

0.45

0.60

0.75

0.90

1.05

1.20

No

rma

lize

d C

on

cen

tra

tion

of A

rse

nic

an

d S

ilica

(C

/C0)

S iO 2

As(V)

In fluent: G roundw aterpH : 7.8As(V): 26 g/LS ilica: 33 m g/L

Experim enta l C onditionsEm pty Bed C ontact T im e: 3.8 m in

Typical Pilot Scale Study: Arsenic Typical Pilot Scale Study: Arsenic Effluent History at City of Effluent History at City of

Rosharon, TXRosharon, TX

0102030405060708090

100

0 10000 20000 30000 40000 50000

Bed Volumes

Ars

enic

ug/

l Inlet As: 27ug/lRun length: 14 daysFlow rate: 1.2 gpmColumn Dia: 3”Column Ht: 2’

Maximum contaminant level (MCL)

Typical Pilot Scale Study: Typical Pilot Scale Study: Arsenic Effluent History at City Arsenic Effluent History at City

of Andrews, TXof Andrews, TX

0102030405060708090

100

0 10000 20000 30000 40000

Ars

en

ic u

g/l

Bed Volumes

Inlet As: 25ug/lRun length: 35 daysFlow rate: 0.2 gpmColumn Dia: 3”Column Ht: 2’

Maximum contaminant level (MCL)

Typical Fixed Bed Sorbent Typical Fixed Bed Sorbent (HIX) Based Arsenic Removal (HIX) Based Arsenic Removal

System for Rural Water UtilitiesSystem for Rural Water Utilities

AVAILABLE AVAILABLE TECHNOLOGIES/TREATMENT TECHNOLOGIES/TREATMENT

METHODSMETHODSThe Technologies/Sorbents that are available in

the marketplace to remove arsenic from drinking

water are:

1. Granular Ferric Oxide (GFH)2. E33 Granular Ferric Oxide (GFO)3. G2 Ferric Oxide Treated Diatomite4. Apyron Aqua-Bind SP60

Most of the above sorbents lack Mechanical Strength

and require pre/post treatmentMost of the above media except HIX and G2 are

notRegenerable. HIX clearly stands out particularly

forsimultaneous removal of Arsenic and other co-

contaminants (U and Ra).

Typical Installed Cost for Fixed Typical Installed Cost for Fixed Bed SystemsBed Systems

PopulationPopulation Served Served

Service Flow Service Flow RateRate

Installed CostInstalled Cost

100100 7 gpm7 gpm $ 20 K$ 20 K

300300 20 gpm20 gpm $ 38 K$ 38 K

500500 35 gpm35 gpm $ 60 K$ 60 K

1,0001,000 70 gpm70 gpm $ 85 K$ 85 K

3,0003,000 200 gpm200 gpm $ 200 K$ 200 K

5,0005,000 350 gpm350 gpm $ 300 K$ 300 K

10,00010,000 700 gpm700 gpm $ 525 K$ 525 K

Typical Operating Cost for HIX Typical Operating Cost for HIX Fixed Bed SystemsFixed Bed Systems

Range of Inlet Arsenic Range of Inlet Arsenic ConcentrationConcentration

Cost/1000 gal of treated Cost/1000 gal of treated waterwater

15 to 30 ppb15 to 30 ppb 30 to 50 cents30 to 50 cents

31 to 60 ppb31 to 60 ppb 50 to 75 cents50 to 75 cents

61 to 100 ppb61 to 100 ppb 75 cents to $1.1075 cents to $1.10

Note: For inlet water containing Arsenic and other co-contaminants like Radium or Uranium, the operating cost for treatment is expected to increase in the range of 40% to 60%