Optimization Stories From the Field...Optimization Stories From The Field Initial Operating Metrics Alum, mg/L 15.6 Post-lime, mg/L 3.92 Dewatering lime, lbs/mo. 76,798 Filter cake,

Optimization Stories From the Field

Marvin Gnagy, P.E., President

PMG Consulting, Inc.

NE District AWWA Canton HOF

August 17, 2017

Optimization Stories From The Field

▪ Optimization practices used in the field▪ Short synopsis

▪ Optimization stories▪ Evaluations made

▪ Technical solutions developed

▪ Implementation and verification

▪ Results achieved

▪ Questions

Agenda

2


3

▪ Define objectives/goals▪ Why should this project be initiated

▪ Develop baseline characteristics▪ Current operations and metrics

▪ Benchmark industry standards or best practices▪ Compare where things are to where you believe they should be

▪ Conduct gap analysis▪ How do I get to the goals?

▪ Tools, capital, training, operating adjustments that might be needed to achieve the goals

Optimization Practices Used in Field

3


4

▪ Establish Implementation strategy▪ Capital needs

▪ Tools, modeling, etc.

▪ Operational changes

▪ Adjustment protocols

▪ Verification procedures

▪ Track progress against objectives/goals▪ Did you meet the objectives and goals?

▪ Did you exceed the objectives and goals?

▪ Did you improve water quality?

▪ Did you improve performance?

Optimization Practices Used in Field

4


Atlanta-Fulton County, Georgia

5


▪ 90 mgd surface water plant▪ Average daily production 44.5 mgd

▪ Reservoir storage from Chattahoochee River

▪ Coagulation/filtration plant▪ Chemical treatment

▪ Solids handling

▪ Disinfection and storage

▪ Finished water pumping to two wholesale distribution systems▪ 400,00 people

Atlanta-Fulton County

6



7

Floc Speed Adjustments Initiative



8

Sedimentation basins with plate settlers


▪ Floc Speed Adjustments Initiative▪ Jagged, feathery floc observed entering the sedimentation process

▪ Measured drive output speeds at different VFD settings

▪ Established rotational output at any VFD setting

▪ Defined current G values for each of four stages

▪ 4 sec-1, 4 sec-1, 3 sec-1, 2 sec-1

▪ Operators afraid of floc shear

▪ Conducted jar testing to establish optimum G values for floc development and settleability

▪ Graphed floc settleability versus G value to find optimum mixing characteristics


9



10

Low density

floc particles

observed in

full-scale

operations



11

y = 0.38399x - 0.03307R² = 0.99695

0.01.02.03.04.05.06.07.08.09.0

10.011.012.013.014.015.016.017.018.019.020.021.022.023.0

0 5 10 15 20 25 30 35 40 45 50 55 60

Sh

aft

Ro

tati

on

al

Sp

eed

, R

PM

Floc Drive Speed, Hz

VFD rotational

speed calibration



12

y = 0.38399x - 0.03307R² = 0.99695

0.01.02.03.04.05.06.07.08.09.0

10.011.012.013.014.015.016.017.018.019.020.021.022.023.0

0 5 10 15 20 25 30 35 40 45 50 55 60

Sh

aft

Ro

tati

on

al

Sp

eed

, R

PM


At any drive

setting



13

y = 0.38399x - 0.03307R² = 0.99695

0.01.02.03.04.05.06.07.08.09.0

10.011.012.013.014.015.016.017.018.019.020.021.022.023.0

0 5 10 15 20 25 30 35 40 45 50 55 60

Sh

aft

Ro

tati

on

al

Sp

eed

, R

PM


At any drive

setting

We know the

rotational

output



14

R² = 0.9996

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

0 10 20 30 40 50 60

Flo

c S

ett

leab

ilit

y, g

pm

/ft

2

First Stage G Value, sec-1

Floc settleability curve from jars



15

R² = 0.9996

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

0 10 20 30 40 50 60

Flo

c S

ett

leab

ilit

y, g

pm

/ft

2


Current G

value, 4 sec-1




16

R² = 0.9996

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

0 10 20 30 40 50 60

Flo

c S

ett

leab

ilit

y, g

pm

/ft

2


Current G

value 4 sec-1

Suggested G value

40 sec-1




17

R² = 0.9996

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

0 10 20 30 40 50 60

Flo

c S

ett

leab

ilit

y, g

pm

/ft

2


Current G

value 4 sec-1

Operating SOR =

1.14 gpm/ft2

Suggested G value

40 sec-1


• Adjusted floc drive speeds to produce suggested G values

• Tracked settled water turbidity online monitoring

• Reduced from 0.5 NTU average to 0.1 NTU average within 4 days

• Possible to reduce coagulant dosage to obtain similar settled turbidity

• Implemented without capital costs


18


• Dewatering accomplished in gravity thickeners, lime amendment to pH 12, sludge conditioning and pumping, plate and frame filter press

• Cake disposal in local landfill

• Cake typically 23% solids (another story)


19


▪ Coagulant reduction could impact other processes and costs▪ Reduced solids production

▪ Reduced lime for dewatering

▪ Reduced post-lime for pH adjustment/corrosion control

▪ Cake disposal

▪ Phase 2 optimization▪ Define current operating costs

▪ Develop potential costs under optimized coagulant dosing

▪ Establish new settled water target values

▪ Verify operating costs from annual operations


20


Initial Operating Metrics

Alum, mg/L 15.6

Post-lime, mg/L 3.92

Dewatering lime, lbs/mo. 76,798

Filter cake, dry tons per year 941

Alum, lbs/MG 132.2

Post-lime, lbs/MG 33.3

Dewatering lime, tons per dry

ton cake 1.832


21

$180,969

$35,400

$66,998

$87,219

2015 Operating Cost Breakdown

Coagulant

Post-lime

Dewatering lime

Cake disposal

Cost savings

Annual operating cost $370,586


Initial Operating Metrics Projected Operating Metrics

Alum, mg/L 15.6 Alum, mg/L 12.5

Post-lime, mg/L 3.92 Post-lime, mg/L 3.2

Dewatering lime, lbs/mo. 76,798 Dewatering lime, lbs/mo. 57,599

Filter cake, dry tons per

year941


year752

Alum, lbs/MG 132.2 Alum, lbs/MG 105.9

Post-lime, lbs/MG 33.3 Post-lime, lbs/MG 27.2

Dewatering lime, tons per

dry ton cake 1.832Dewatering lime, tons per

dry ton cake 1.832


22

Expected 20% overall reduction in operating costs


▪ Implementation and verification of annual operations▪ Month-to-month tracking and comparisons first year

▪ Calculation of operating costs and actual savings

▪ Adjustment of operating metrics

▪ Summation of first-year operations


23

Dewatering lime feed


Initial Operating Metrics Actual Operating Metrics

Alum, mg/L 15.6 Alum, mg/L 9.6

Post-lime, mg/L 3.92 Post-lime, mg/L 2.9

Dewatering lime, lbs/mo. 76,798 Dewatering lime, lbs/mo. 51,123


year941


year650

Alum, lbs/MG 132.2 Alum, lbs/MG 79.8

Post-lime, lbs/MG 33.3 Post-lime, lbs/MG 23.7

Dewatering lime, tons per

dry ton cake 1.832Dewatering lime, tons per

dry ton cake 1.832


24



25

$100,280

$24,392

$44,599$58,704

$142,611


Coagulant

Post-lime

Dewatering lime

Cake disposal

Cost savings


Actual 38% reduction in annual costs obtained

Excellent coordination between operations and

engineering toward a common goal

$180,969

$35,400

$66,998

$87,219


Coagulant

Post-lime

Dewatering lime

Cake disposal



Buffalo Water, New York

26


▪ 120 mgd surface water plant, originally 1922▪ Average daily production 71 mgd

▪ Direct draw from eastern basin Lake Erie▪ Just upstream of Niagara River


▪ Solids handling


▪ Finished water pumping to distribution system▪ 257,00 people

Buffalo Water

27

Lake Intake Structure


Buffalo Water

28

Coagulant Mixing Initiative


▪ SternPac coagulant used since 1990’s▪ Raw water turbidity averages 2 NTU

▪ Settled water turbidity averaged 0.85 NTU

▪ Filter run times 72 hours

▪ Low head loss, possible optimization initiaitive

▪ One coagulant feed point▪ Low service discharge header

▪ Relatively poor mixing

▪ Coagulant not contacting within pump flow depending on pump in operation

Buffalo Water

29


Buffalo Water

30

Coagulant Feed Line

Discharge header


Buffalo Water

31

Coagulant Feed Line

Discharge header


Buffalo Water

32

Coagulant Feed Line

Discharge header


Buffalo Water

33

Coagulant Feed Line

Changed

feed point to

each pump

discharge to

improve

mixing

Discharge header


▪ Mixing improvement immediately led to 17% reduction in coagulant dosage▪ 9.7 mg/L to 8 mg/L

▪ Coagulant reduction also impacted▪ Sludge dewatering

▪ Polymer conditioning

▪ Cake disposal

▪ Operating costs

Buffalo Water

34


Buffalo Water

35

Floc and sed basins cleaned annually, no sludge

removal equipment


Buffalo Water

36

Sludge pumped to backwash lagoon for further processing


Buffalo Water

37

Lagoon contents pumped to

conditioning tank for polymer

addition


Initial Operating Metrics

SternPac, mg/L 9.67

Dewatering polymer,

lbs/ton12.95

Cake production, dry

tons/yr931

Cake solids, % 22.6

Buffalo Water

38

$244,236$177,669

$48,037

Coagulant

Disposal

Polymer


Annual Operating Cost $469,941


Buffalo Water

39

Initial Operating Metrics Actual Operating Metrics

SternPac, mg/L 9.67 SternPac, mg/L 8.0

Dewatering

polymer, lbs/ton12.95

Dewatering polymer,

lbs/ton10.13

Cake production,

dry tons/yr931

Cake production, dry

tons/yr725

Cake solids, % 22.6 Cake solids, % 32.1


Buffalo Water

40

Actual 33.5% reduction realized in annual costs

$196,621

$95,023

$20,640

$157,658

Coagulant

Disposal

Polymer

Savings



$244,236$177,669

$48,037

Coagulant

Disposal

Polymer




Buffalo Water

41

Actual 33.5% reduction realized in annual costs

Annual cost savings $157,657

$196,621

$95,023

$20,640

$157,658

Coagulant

Disposal

Polymer

Savings



$244,236$177,669

$48,037

Coagulant

Disposal

Polymer




▪ Future optimization plans▪ Floc speed adjustments (underway with another 12% coagulant

reduction)

▪ Incorporate activated carbon reactors for T&O/cyanotoxin treatment

▪ Install conventional rapid mix to further reduce coagulant feed

▪ Add streaming current monitors to automate coagulant feed

▪ Optimize filter performance

Buffalo Water

42


NEMRWSD – Tupelo, MS

43



44


▪ 18 mgd surface water plant drawing from Tombigbee River▪ Average daily production 12 mgd


▪ Solids handling


▪ Final chloramination

▪ Finished water pumping to four wholesale distribution systems▪ ≈70,000 people


45



46

Disinfection Optimization Initiative


▪ Filtered water disinfected using free chlorine▪ Water flows through three clearwells for CT compliance

▪ Final pass ammonia added for chloramine conversion

▪ High TOC in filter effluent is common

▪ HAA5 formation issues existed previously

– 2 periods greater than 60 µg/L LRAA

▪ Residual monitored continuously

▪ Clearwells supply high service pumps▪ Six pumps and three large diameter distribution force mains to the

supply district


47



48

AMMONIA

RESIDUAL

CHLORINE

Average total

chlorine 3.3

mg/L

RESIDUAL

RESIDUAL

RESIDUAL



49

AMMONIA

RESIDUAL

CHLORINE

Average total

chlorine 3.3

mg/L

RESIDUAL

RESIDUAL

RESIDUAL

Were not taking

advantage of 48” piping

contact time


▪ Developed CT model to predict potential chemical feed and monitoring locations▪ Meet CT requirements according to water temperature variations

▪ Water temp variations 7oC to 30oC

▪ Minimize HAA5 formation in summer months

▪ Produce chloramines to slow HAA5 formation

▪ Install new ammonia feed and residual monitoring points as predicted

▪ Obtain Mississippi DOH approvals▪ Changes in feed points

▪ CT monitoring and compliance


50



51

8,200 7.00 7.0 8.0 0.80 2.80 0.05 0.05 0.05 21.9

CUMMULATIVE

MINUTES

FRONT WEIR

CHAMBER PRETREATMENT 26.4 26.4

END OF WEIR

CHAMBER 1 WEIR CHAMBER 0.6 27.0

END OF

CLEARWELL A CLEARWELL A 5.5 32.5

END OF

CLEARWELL B CLEARWELL B 22.4 54.9END OF

CLEARWELL C CLEARWELL C 5.5 60.4 1.02

NORTHEAST MISSISSIPPI REGIONAL WATER SUPPLY DISTRICT - TUPELO, MS

CT CALCULATIONS MODEL

LOWEST

CLEARWELL

OPERATING

LEVEL, ft.

WEIR CHAMBER

FREE CHLORINE

CONC. mg/L

PRETREATMENT

BASINS FREE

CHLORINE

CONC. mg/L

CLEARWELL B

FREE CHLORINE

CONC. mg/L

1 = SELECT CURRENT

AMMONIA FEED POINT CUMMULATIVE CT (mg/L-minutes)

PEAK HOURLY

TREATMENT

FLOW, gpm

HIGHEST

WATER pH

LOWEST

WATER TEMP. oC

DISINFECTION CONTACT

TIMES - MINUTES

CLEARWELL A

FREE CHLORINE

CONC. mg/L

CLEARWELL C

FREE

CHLORINE

CONC. mg/L

22.8

22.8

22.8

CT RATIO22.8

21.1

REQUIRED

CT FROM

TABLES

mg/L-min.

1.02

7.0


▪ Model suggested CT compliance through weir chamber using free chlorine▪ Ammonia feed after weir chamber to slow HAA5 formation

▪ Residual monitoring downstream of feed point

▪ Added multiple feed point and residual monitors to clearwell arrangements


52



53

AMMONIA 4

RESIDUAL 4

CHLORINE

Multiple NH3

feed points

based on water

temp changes

RESIDUAL 3

RESIDUAL 1

RESIDUAL 2

AMMONIA 1

AMMONIA 2AMMONIA 3


▪ Solved HAA5 issues with ammonia feed changes to slow formation▪ LRAA 38 µg/L

▪ Some residual maintenance issues in parts of distribution system

▪ Investigation into residuals suggested northern edge impacted significantly▪ Low total chlorine residuals

▪ Elevated HAA5 levels

▪ Some odors observed

▪ Chlorine decay evaluations conducted


54


▪ Large distribution system and multiple storage tanks

▪ Northern most tank area where most of low residuals occur▪ Total chlorine depleted less than

1.0 mg/L

▪ Chlorine decay analysis (bulk water in lab)▪ Define decay coefficient and

develop computer model

▪ Adjust model for piping decay along with bulk water decay

▪ Predict water age in distribution system

Tupelo, MS

55

Water

Plant


56

NEMRWSD – Tupelo, MSWater System A

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0

Decay Period, days

Fre

e C

hlo

rin

e R

em

ain

ing

, m

g/

L

Temp = 21oC

Raw data in

graphical

form


57


0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0

Decay Period, days

Fre

e C

hlo

rin

e R

em

ain

ing

, m

g/

L

Temp = 21oC

Exponential

trend line

selection and

overlay


58


y = 1.800e-0.284x

R2 = 0.999

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0

Decay Period, days

Fre

e C

hlo

rin

e R

em

ain

ing

, m

g/

L

Temp = 21oC

Trend line

equation and R2

correlation


59


y = 1.800e-0.284x

R2 = 0.999

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0

Decay Period, days

Fre

e C

hlo

rin

e R

em

ain

ing

, m

g/

L

Temp = 21oC

Identified

decay

coefficient

(kb) is 0.284



60

• Conducted decay

analysis for Tupelo

water in laboratory• Initial residual 3.05

mg/L

• Observed total chlorine

residual for 21 days• Residual declined

below 1.9 mg/L


▪ Determine decay coefficient (k) from equation

Ct=Coe(-kt)


61

Water System B

y = 2.7835e-0.0196x

R2 = 0.9442

1.7

1.8

1.9

2.0

2.1

2.2

2.3

2.4

2.5

2.6

2.7

2.8

2.9

3.0

3.1

0 2 4 6 8 10 12 14 16 18 20 22

Decay Period, days

To

tal

Ch

lori

ne R

em

ain

ing

, m

g/

L

Temp = 20oC


▪ Determine decay coefficient (k) from equation

Ct=Coe(-kt)


62

Water System B

y = 2.7835e-0.0196x

R2 = 0.9442

1.7

1.8

1.9

2.0

2.1

2.2

2.3

2.4

2.5

2.6

2.7

2.8

2.9

3.0

3.1

0 2 4 6 8 10 12 14 16 18 20 22

Decay Period, days

To

tal

Ch

lori

ne R

em

ain

ing

, m

g/

L

Temp = 20oC

Identified

water decay

coefficient (kb)

is 0.0196



63

NE Mississippi Regional Water Supply District

Tupelo, MS

Total Chlorine Decay Model

Temp 30oC (temp varies 7

oC to32

oC)

k 0.0392

Days 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

3.20 3.08 2.96 2.85 2.74 2.63 2.53 2.43 2.34 2.25 2.16 2.08 2.00 1.92 1.85 1.78 1.71 1.64 1.58 1.52 1.46 1.41

3.10 2.98 2.87 2.76 2.65 2.55 2.45 2.36 2.27 2.18 2.10 2.02 1.94 1.86 1.79 1.72 1.66 1.59 1.53 1.47 1.42 1.36

3.00 2.88 2.77 2.67 2.57 2.47 2.37 2.28 2.19 2.11 2.03 1.95 1.88 1.80 1.73 1.67 1.60 1.54 1.48 1.43 1.37 1.32

2.90 2.79 2.68 2.58 2.48 2.38 2.29 2.20 2.12 2.04 1.96 1.89 1.81 1.74 1.68 1.61 1.55 1.49 1.43 1.38 1.33 1.27

2.80 2.69 2.59 2.49 2.39 2.30 2.21 2.13 2.05 1.97 1.89 1.82 1.75 1.68 1.62 1.56 1.50 1.44 1.38 1.33 1.28 1.23

2.70 2.60 2.50 2.40 2.31 2.22 2.13 2.05 1.97 1.90 1.83 1.76 1.69 1.62 1.56 1.50 1.44 1.39 1.33 1.28 1.23 1.19

2.60 2.50 2.40 2.31 2.22 2.14 2.06 1.98 1.90 1.83 1.76 1.69 1.63 1.56 1.50 1.45 1.39 1.34 1.28 1.24 1.19 1.14

2.50 2.40 2.31 2.22 2.14 2.06 1.98 1.90 1.83 1.76 1.69 1.63 1.56 1.50 1.44 1.39 1.34 1.28 1.24 1.19 1.14 1.10

2.40 2.31 2.22 2.13 2.05 1.97 1.90 1.82 1.75 1.69 1.62 1.56 1.50 1.44 1.39 1.33 1.28 1.23 1.19 1.14 1.10 1.05

2.90 2.79 2.68 2.58 2.48 2.38 2.29 2.20 2.12 2.04 1.96 1.89 1.81 1.74 1.68 1.61 1.55 1.49 1.43 1.38 1.33 1.27

2.80 2.69 2.59 2.49 2.39 2.30 2.21 2.13 2.05 1.97 1.89 1.82 1.75 1.68 1.62 1.56 1.50 1.44 1.38 1.33 1.28 1.23

2.70 2.60 2.50 2.40 2.31 2.22 2.13 2.05 1.97 1.90 1.83 1.76 1.69 1.62 1.56 1.50 1.44 1.39 1.33 1.28 1.23 1.19

2.60 2.50 2.40 2.31 2.22 2.14 2.06 1.98 1.90 1.83 1.76 1.69 1.63 1.56 1.50 1.45 1.39 1.34 1.28 1.24 1.19 1.14

2.50 2.40 2.31 2.22 2.14 2.06 1.98 1.90 1.83 1.76 1.69 1.63 1.56 1.50 1.44 1.39 1.34 1.28 1.24 1.19 1.14 1.10

2.40 2.31 2.22 2.13 2.05 1.97 1.90 1.82 1.75 1.69 1.62 1.56 1.50 1.44 1.39 1.33 1.28 1.23 1.19 1.14 1.10 1.05

2.30 2.21 2.13 2.05 1.97 1.89 1.82 1.75 1.68 1.62 1.55 1.50 1.44 1.38 1.33 1.28 1.23 1.18 1.14 1.09 1.05 1.01

2.20 2.12 2.03 1.96 1.88 1.81 1.74 1.67 1.61 1.55 1.49 1.43 1.38 1.32 1.27 1.22 1.18 1.13 1.09 1.05 1.01 0.97

2.10 2.02 1.94 1.87 1.80 1.73 1.66 1.60 1.54 1.48 1.42 1.37 1.31 1.26 1.21 1.17 1.12 1.08 1.04 1.00 0.96 0.92

2.00 1.92 1.85 1.78 1.71 1.64 1.58 1.52 1.46 1.41 1.35 1.30 1.25 1.20 1.16 1.11 1.07 1.03 0.99 0.95 0.91 0.88

1.90 1.83 1.76 1.69 1.62 1.56 1.50 1.44 1.39 1.34 1.28 1.24 1.19 1.14 1.10 1.06 1.02 0.98 0.94 0.90 0.87 0.83

1.80 1.73 1.66 1.60 1.54 1.48 1.42 1.37 1.32 1.27 1.22 1.17 1.13 1.08 1.04 1.00 0.96 0.93 0.89 0.86 0.82 0.79

1.70 1.63 1.57 1.51 1.45 1.40 1.34 1.29 1.24 1.20 1.15 1.11 1.06 1.02 0.98 0.94 0.91 0.87 0.84 0.81 0.78 0.75

1.60 1.54 1.48 1.42 1.37 1.32 1.26 1.22 1.17 1.12 1.08 1.04 1.00 0.96 0.92 0.89 0.86 0.82 0.79 0.76 0.73 0.70

1.50 1.44 1.39 1.33 1.28 1.23 1.19 1.14 1.10 1.05 1.01 0.98 0.94 0.90 0.87 0.83 0.80 0.77 0.74 0.71 0.69 0.66

1.40 1.35 1.29 1.24 1.20 1.15 1.11 1.06 1.02 0.98 0.95 0.91 0.88 0.84 0.81 0.78 0.75 0.72 0.69 0.67 0.64 0.62

1.30 1.25 1.20 1.16 1.11 1.07 1.03 0.99 0.95 0.91 0.88 0.85 0.81 0.78 0.75 0.72 0.69 0.67 0.64 0.62 0.59 0.57

1.20 1.15 1.11 1.07 1.03 0.99 0.95 0.91 0.88 0.84 0.81 0.78 0.75 0.72 0.69 0.67 0.64 0.62 0.59 0.57 0.55 0.53

1.10 1.06 1.02 0.98 0.94 0.90 0.87 0.84 0.80 0.77 0.74 0.72 0.69 0.66 0.64 0.61 0.59 0.57 0.54 0.52 0.50 0.48

1.00 0.96 0.92 0.89 0.86 0.82 0.79 0.76 0.73 0.70 0.68 0.65 0.63 0.60 0.58 0.56 0.53 0.51 0.49 0.48 0.46 0.44

Init

ial T

ota

l C

l 2, m

g/L


▪ Average water age less than 3 days▪ Southern areas less than 2 days

water age

Tupelo, MS

64

Water

Plant0.5 days

1.2 days

1.2 days

1.2 days

1.2 days

1.2 days

1.2 days

2.3 days



water age

▪ Northern areas increasing water age to 4.5 days

Tupelo, MS

65

Water

Plant0.5 days

1.2 days

1.2 days

1.2 days

1.2 days

1.2 days

1.2 days

2.3 days

4.3 days

4.5 days

4.5 days



water age

▪ Northern areas increasing water age to 4.5 days

▪ Baldwyn Tank (north) water age 22 days

▪ Installed PAX tank mixer to reduce water stagnation

▪ Within 1 day total chlorine residuals increased to 2.5 mg/L

▪ Reduced HAA5s 30% in Baldwyn Tank area from stagnant water

Tupelo, MS

66

Water

Plant0.5 days

1.2 days

1.2 days

1.2 days

1.2 days

1.2 days

1.2 days

2.3 days

4.3 days

4.5 days

4.5 days

22 days


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Documents

Optimization Stories From the Field...Optimization Stories From The Field Initial Operating Metrics Alum, mg/L 15.6 Post-lime, mg/L 3.92 Dewatering lime, lbs/mo. 76,798 Filter cake,