ready, aims, fire: treatment solutions for arsenic, iron ...flow rate 100 gpm arsenic, raw 0.028...

Ready, AIMS, Fire:Treatment Solutions for Arsenic,

Iron, Manganese, and Sulfide2018 PAAW Annual Conference

Brit MerolaAdEdge Water Technologies

About AdEdge Started company in 2002, target was the emerging arsenic marketplace to the new lower standard of 10 ppb.

Over 450 installations for arsenic removal…more than any company globally

We have sold over 750 systems into 15 countries/45 States/9 Canadian Provinces

Multiple contaminant specialist 20/20 matrix

Design solutions from 0.5 gpm to 12 MGD

AdEdge Treatment Matrix

Systems by Contaminants

Contaminant Number of Systems

(different technologies & media)

Arsenic removal > 450 systems

Iron, Manganese & Sulfide removal > 250 systems

Nitrate removal > 15 systems

Radionuclides > 30 systems

Color, Odor, & TDS > 30 systems

Purpose / Agenda

Arsenic, Iron, Manganese, and Sulfide Contamination

Treatment Options Adsorption

Oxidation/Filtration

Coagulation/Filtration

EPA Max Contaminant Levels

MCL

As = 0.01 mg/L

Secondary MCL

Fe = 0.3 mg/L

Mn = 0.05 mg/L

SO4 = 250 mg/L Sulfide > 0.5 – 1 mg/L causes aesthetic issues

7

• Adsorption (media-based)• Various Adsorbents

• Oxidation/Filtration

• Coagulation/Filtration

• Anion Exchange

• Reverse Osmosis

Primary Arsenic Treatment Options

Technology Considerations

AdsorptionSimple to operateLow Capital/Labor Cost and Ease of UseIdeal for water with low interferences

Oxidation + FiltrationCo-contaminant removal (with naturally occurring high Fe)Moderate Capital/Lowest Opex

Coagulation + FiltrationCo-Contaminant removal (with coagulant addition)Moderate Capital/Opex

Common Methods for As Treatment


Oxidation + Filtration Oxidant Addition

Aeration (Oxygen) + FiltrationKineticspH

Cation Exchange (Softening)Water chemistry (hardness)Salt and Brine

Polyphosphate (Sequestering)NOT REMOVALDosing challenges

Common Methods for Fe/Mn Treatment

10

Hydrogen sulfide (H2S) is a gas that is insoluble in water, but the gas remains trapped within the water

Concentrations from 0.5 – 1 ppm – musty, swamp smell

Concentrations greater than 1 ppm smell like rotten eggs and create corrosion issues to plumbing

Health risks include nausea, stomach pain, and laxative effect

Sulfide – Why should it be removed?


Oxidation + Filtration Oxidant Addition

Air StrippingSulfide < 2.0 ppmSulfide may still be noticeablepH

Carbon Filtration Quickly exhausted, <0.3 ppm ideal

Common Methods for Sulfide Treatment

Adsorption(Arsenic)

Service Flow In

Adsorption Media

Underbedding / gravel

Head space forbackwash expansion

Backwash In

Backwash out

Service out

Underdrain

Arsenic Treatment: Adsorption

Single or multi-vessel configurationDownflow service Parallel or Lead/LadBed depths 34”-36” typicalHub/laterals and distributor internalsPeriodic backwashing

Arsenic Treatment:Adsorption – Granular Ferric Oxide (GFO)

Iron-based adsorbent media

Bayoxide E33 Granular Ferric Oxide media

Dry, granular product

High capacity commercial media

Reduces As (III) and As (V)

Operates over pH range (5.5 – 8.5)

Non-hazardous waste when spent

NSF 61 Certification

12 years of development and application, & commercial use

Arsenic Treatment:Adsorption Media Life Performance Factors

Incomplete water data for design

High iron or manganese (>0.3, 0.05 mg/L)

Arsenic (III) with no oxidation

High silica >45 mg/L

High phosphate >0.4 mg/L

High pH > 8.3

Presence of sulfides

Arsenic Treatment: Adsorption Backwashing and Disposal

Backwash every 45-60 days

Manual valve system OK

Backwash Recycle

Media non-hazardous waste when spent

Accepted by sanitary landfill after TCLP

Richlandtown, PAFlow Rate 100 gpm

Arsenic, Raw 0.028 mg/L

Fe, Raw 0.8 mg/L

Media E33

BW Frequency 1x/month

InstallationDate

Summer 2007

Bakersfield, CAFlow Rate 700 gpm


Media E33

BW Frequency Every 30 – 90 days

Installation Date Fall 2017

Oxidation Filtration and Coagulation

Filtration

Filtration Treatment Technologies

Oxidation Filtration Naturally occurring Fe + As

(ratio >30:1)

Elevated Fe/Mn/H2S

Coagulation Filtration Coagulant addition

Elevated As + Fe

As + Fe + Mn

As + Mn

Oxidation/Filtration (O/F) – (Fe/Mn/H2S)

Oxidant

Oxidation / Filtration

Media System

Backwash WasteOrH2Zero System

Storage / Distribution

Backwash Supply

Oxidation/Filtration (O/F) – (As/Fe/Mn/H2S)

Oxidant

Oxidation / Filtration

Media System



Backwash Supply

OxidantpH Adjust

Coagulation/Filtration (C/F) – (As/Fe/Mn/H2S)

Oxidant

Coagulation / Filtration

Media System



Backwash Supply

OxidantFerric ChloridepH AdjustPolymer

Oxidation/Filtration:Design Basis

GPM = Gallons per Min

Media Surface Area = PI*r2

Oxidation/Filtration Media:Coated Sand

Coated Sand (ADGS+)

Oxidant(s) Chlorine (sodium hypochlorite)

MnO2 Content 3% - 5%

PerformanceFe < 7 mg/LMn < 0.5 mg/L

Loading Rate 3 gpm/sqft – 6 gpm/sqft

Backwash Rate 12 gpm/sqft

Conneaut Lake, PAFlow Rate 250 gpm


Fe, Raw 0.8 mg/L

Media ADGS+

BW Frequency 2x/week

InstallationDate

Summer 2009

Oxidation/Filtration Media:Solid Phase Manganese Dioxide

20% MnO2 (AD26L)


MnO2 Content 15% - 20%

PerformanceFe < 7 mg/LMn < 1.2 mg/L



All Seasons, PAFlow Rate 27 gpm

Iron, Raw 0.7 mg/L

Mn, Raw 0.88 mg/L

Media AD26L

BW Frequency Every 4 days

InstallationDate

Winter 2017

New Windsor, NYFlow Rate 5000 gpm

Fe, Raw 0.12 mg/L

Mn, Raw 1.1 mg/L

Media AD26L

BW Frequency Daily

InstallationDate

Summer 2018

Oxidation/Filtration Media:Solid Phase Manganese Dioxide

80% MnO2 (AD26)


MnO2 Content > 80%

PerformanceFe < 7 mg/LMn < 2 mg/L



Hemlock Farms, PAFlow Rate 600 gpm

Iron, Raw 0.35 mg/L

Mn, Raw 0.4 mg/L

Media AD26


InstallationDate

Winter 2015

Honesdale, PAFlow Rate 270 gpm

Sulfides, Raw Present

Mn, Raw 0.2 mg/L

Media AD26


InstallationDate

Summer 2010

Wallenpaupack, PA Flow Rate 45 gpm

Sulfides, Raw 630 ppb

Media AD26


InstallationDate

Spring 2009

9.5 feet

17.5 feet

7.5 feet

13 feet

45% SMALLER

3 gpm/sqft

9 gpm/sqft

Higher MnO2 Filter systemConventional Filter

Why Media Selection is Important

Oxidation/Filtration:Special Considerations

Ammonia (high chlorine demand)

pH (> 8)

Sulfides (oxidant demand)

TOC > 1 mg/L (oxidant demand)

Adverse reactions with TOC and Chlorine to form disinfection by products (THMs, HAA5, etc)

Oxidation/FiltrationSystem Operational Cycles

Service (downflow)◦ 12-32 hours of continuous run time◦ Run length depends on Fe, Mn concentrations

Backwash (upflow 8 min)◦ Removed filtered suspended Fe/Mn solids◦ Backwash until water runs clear

Rinse (downflow 2 min)◦ Flushes out any remaining residual ppt Fe and

Mn in the bed before service

Thank You

ready, aims, fire: treatment solutions for arsenic, iron ...flow rate 100 gpm arsenic, raw 0.028...

Documents