Do Cation Exchange Systems Affect the Chlorination Process?€¦ · NH 3 + H 2O NH 4 + + OH- Total...

transcript

Do Cation Exchange Systems Affect the Chlorination Process?

Presented By:

Jeffrey W. Freeman, P.E., CFM, LEED APEngineering Enterprises, Inc.

March 22, 2016

Presentation Overview

Ebony-Ammonia & Ammonium-Ivory

Gimme A Breakpoint

Holy # of Test Methods

Cation Exchange Treatment Exposed

Presentation Overview (Cont.)

Evidence

More Evidence

Take That, Variable Ammonia!

Acknowledgements and Q&A

Ammonia Dissolution In Water

NH3 + H2O NH4+ + OH-

Total Ammonia NH3 + NH4+

Free Ammonia NH3 Only

Ammonia Ammonium

pKa = 9.25

Source: Manual for Bosanska Krupa Nov. 2009

Ammonia & Ammonium DissolutionpH = 9.25; Temperature = 20OC

Source: Manual for Bosanska Krupa Nov. 2009

Ammonia & Ammonium DissolutionpH = 9.25; Temperature = 20OC

Monochloramine Development

NH3 + HOCl NH2Cl + H2O

Dichloramine Development

NH2Cl + HOCl NHCl2 + H2O

Nitrogen Trichloride Development

NH2Cl + HOCl NCl3 + H2O

Chloramine Chemistry

Gimme a Breakpoint

Breakpoint Chlorination Overview

Chlorine Added

Total Chlorine Re

sidual

Breakpoint

Gimme a Breakpoint

Breakpoint Chlorination Overview (Cont.)

Chlorine Added

Total &

Free Am

Total Chlorine Re

sidual

Free Ammonia

Total Ammonia

MonochloramineTo Dichloramine

TotalChlorine

MonochloramineDevelopment

DichloramineTo N‐ Trichloride

NitrogenTrichloride

FreeChlorine

TotalChlorine

Gimme a Breakpoint

Breakpoint Chlorination Overview (Cont.)

Chlorine Added

Total &

Free Am

Total Chlorine Re

sidual

Free Ammonia

Total Ammonia

MonochloramineTo Dichloramine

TotalChlorine

Monochloramine DichloramineTo N‐ Trichloride

NItrogenTrichloride

FreeChlorine

TotalChlorine

Cl2:NH3‐N<5:1 Cl2:NH3–N>5:1 Cl2:NH3 –N>7.6 ‐ 9:1

Cl2:NH3–N = 5:1 Cl2:NH3–N = 7.6 ‐ 9:1

Gimme a Breakpoint

Five (5) Recommended Parameters To Confirm Breakpoint Has Been Achieved: Free Ammonia

Total Ammonia

Monochloramine

Total Chlorine

Free Chlorine

Typical Ammonia Test Methods Nessler Method: No Longer

Standard Method Approved Salicylate Method: Recommend

For Total Ammonia Indophenol Method:

Recommend For Free Ammonia & Monochloramine

Ion Selective Electrode: Ideal Method For Precision, But Higher Capital & O&M Costs

Typical Chlorine Test Methods DPD (N,N Diethyl-1,4 Phenylendediamine Sulfate)

Recommended For Total Chlorine and Free Chlorine, If Breakpoint Achievement Has Been Confirmed

Used With Many Test Kits/Analyzers Free Chlorine Must Be Read Within a Minute of Sample

Preparation Total Chlorine To Be Read Within 3 – 5 Minutes After Sample

Prepared

Indophenol Recommended For Free Chlorine Confirmation It Is Not An IEPA Approved Method For Free Chlorine

Measurement

DPD Free Chlorine Test Method Additional Comments Chloramines Are Known To Interfere With the Free Chlorine DPD

Method The Longer The Sample Sits, the Greater the Amount of Interference Occurs

DPD Method Is Accurate When Chloramines Are Not Present

Excerpts From Hach DPD Free Chlorine Test Method Instructions

Indophenol Free Chlorine Test Method Additional Comments It Is Not An IEPA Approved Test Method Chloramines Do Not Interfere With Method It Is a Good Check To Confirm Past Breakpoint

Excerpts From Hach Indophenol Free Chlorine Test Method Instructions

Cation Exchange Treatment Summary General Definition of Ion Exchange Treatment

(Source: New Hampshire Department of Environmental Services):

Ion exchange (IE) is a water treatment method where one or more undesirable contaminants are removed from water by exchange with another non-objectionable, or less objectionable substance. Both the contaminant and the exchanged substance must be dissolved and have the same type (+,-) of electrical charge.

Cation Exchange (CE) Treatment Targets Cations Ions With + Charge

Typical Regenerant is Sodium Chloride (NaCl)

Typical Target Cations In NE IL

Source: http://science notes.org/use‐periodic‐table/

HardnessCations

Barium &Radium

Sodium

Lead 2+

Iron 2+

Copper 2+

Zinc 2+

Affinity (/əˈfinədē/): [Biochemistry]the degree to which a substance tends to combine with another. (Source: www.google.com)

Source: Water Quality & Treatment, AWWA

Cation Exchange Treatment ExposedIon Exchange General Exchange Process

HARDNESS CATIONS

SchematicCation

Exchange Resin Bead

Radium

Barium

Calcium

Magnesium

Ammonium

Sodium

Na+Na+

Na+Na+Na+

Na+Na+

Na+Na+Na+Na+Na+

Na+Na+

Na+ Na+

Ca2+ Ca2+ Ca2+ Mg2+ Mg2+ Mg2+

SchematicCation

Exchange Resin Bead

RADIUM & BARIUM CATIONS

Radium

Barium

Calcium

Magnesium

Ammonium

Sodium Na+Na+

Na+Na+

Na+ Na+

Ca2+ Mg2+

Ra2+ Ra2+ Ba2+ Ba2+

SchematicCation

Exchange Resin Bead

AMMONIUM CATIONS

Radium

Barium

Calcium

Magnesium

Ammonium

Sodium Na+Na+

Na+Na+

Na+ Na+

Ca2+ Mg2+

NH4+ NH4

SchematicCation

Exchange Resin Bead

MORE HARDNESS CATIONS

Radium

Barium

Calcium

Magnesium

Ammonium

SodiumNa+

Na+ Na+

Ca2+ Mg2+

Ba2+NH4+

Ca2+ Mg2+

Na+Na+

SchematicCation

Exchange Resin Bead

REGENERATION

Radium

Barium

Calcium

Magnesium

Ammonium

Sodium Na+

Ca2+ Mg2+

Ba2+NH4+

Ca2+ Mg2+

Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+

Na+ Na+

Ion Exchange WTP Process Flow Schematic

Water DistributionSystem

Backwash SurgeTank

WellNo. 1

SanitarySewerSystem

WellNo. 2

CationExchangeUnits

NaClRegeneration

System

Fl PO4 Cl2

Flow Control Valve

Bypass

Evidence

Theory Confirmation No. 1 Village of Montgomery Wells No. 14 &

15 WTP Background Well No. 14 Ironton Galesville DSS

Well Raw Water Hardness = 235 mg/l as CaCO3

Combined Radium = 6.6 pCi/l

WTP Contains Five (5) CE Units With Bypass

Flouride, Polyphosphate and Chlorine Gas Added After CE Units

Treated Water Distributed Directly Into System

Evidence

Theory Confirmation No. 1 (Cont.) Sampling & Testing Summary

Occurred Every 30 Minutes From 8:00 AM – 2:00 PM on April 3, 2013

Testing Locations Raw Water Post CE/Pre-Chlorination Composite Finished

Tested For Five (5) Test Parameters – Free & Total Ammonia, Chloramine, Free & Total Chlorine

Note: Chlorine Dose = 1.9 mg/l

Evidence

Wells No. 14 & 15 WTP Sample Locations

WellNo. 14

WellNo. 15

CationExchangeUnits

Fl PO4 Cl2

Flow Control Valve

BypassMeter

Post CE / Pre‐Chlor

(Composite)

Finished

Evidence

Raw Water Ammonia LevelsWELL NO. 14 AND WELLS NO. 14 & 15 WTP

Evidence

Raw & Post CE / Pre-Chlor Ammonia LevelsWELL NO. 14 AND WELLS NO. 14 & 15 WTP

Evidence

Finished Ammonia & Chloramine LevelsWELL NO. 14 AND WELLS NO. 14 & 15 WTP

Mono To Di Near BP Mono To Di

Evidence

Finished Ammonia & Chlorine LevelsWELL NO. 14 AND WELLS NO. 14 & 15 WTP

Mono To Di Past BP Mono To Di

Evidence

Raw & Finished Ammonia & Chlorine LevelsWELL NO. 14 AND WELLS NO. 14 & 15 WTP

Evidence

Finished Chlorine ResidualsWELL NO. 14 AND WELLS NO. 14 & 15 WTP

More Evidence

Theory Confirmation No. 2 Village of Montgomery Well No. 8 WTP Background

Well No. 8 Ironton Galesville DSS Well Raw Water Hardness = 210 mg/l as CaCO3

Combined Radium = 11.5 pCi/l

WTP Contains Three (3) CE Units With Bypass Flouride, Polyphosphate and Chlorine Gas Added After CE Units Treated Water Distributed Directly Into System

More Evidence

Theory Confirmation No. 2 (Cont.) Sampling & Testing Summary

Occurred Every 30 Minutes From 8:00 AM – 2:00 PM on May 20, 2013

Testing Locations Raw Water Post CE/Pre-Chlorination Finished

Tested For Five (5) Test Parameters – Free & Total Ammonia, Chloramine, Free & Total Chlorine

Note: Chlorine Dose = 1.9 mg/l

More Evidence

Well No. 8 WTP Sample Locations

WellNo. 14

CationExchangeUnits

Fl PO4 Cl2

Flow Control Valve

BypassMeter

Post CE / Pre‐Chlor

(Composite)

Finished

More Evidence

Raw Water Ammonia LevelsWELL NO. 8 AND WELL NO. 8 WTP

More Evidence

Raw & Post CE / Pre-Chlor Ammonia LevelsWELL NO. 8 AND WELL NO. 8 WTP

Total NH3 @ 13:30Softener 1: 0 mg/lSoftener 2: 0 mg/lSoftener 3: 2.1 mg/l

Softener 3In

Regen.

More Evidence

Mono To DiBP Achieved Near BP

Finished Ammonia & Chlorine LevelsWELL NO. 8 AND WELL NO. 8 WTP

More EvidenceRaw & Finished Ammonia & Chlorine Levels

WELL NO. 8 AND WELL NO. 8 WTP

More Evidence

Finished Chlorine ResidualsWELL NO. 8 AND WELL NO. 8 WTP

Take That, Variable Ammonia!

Wells No. 14 & 15 WTP Sample Locations

WellNo. 14

WellNo. 15

CationExchangeUnits

Fl PO4

Flow Control Valve

BypassMeter

Ammonia &Monohloramine

Analyzer

FreeChlorineAnalyzerPLC

A Big Thank You To:

Village of Montgomery

Bob Spon (Spon Water Consulting)

Terry Engelhardt (Hach)

Jeffrey W. Freeman, P.E., CFM, LEED APVice PresidentEngineering Enterprises, Inc.jfreeman@eeiweb.com(630) 466-6700

Do Cation Exchange Systems Affect the Chlorination Process?€¦ · NH 3 + H 2O NH 4 + + OH- Total...

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