Improving TOCs, DBPs, and Chlorine Residuals

4/2/2012
Improving TOCs, DBPs, and
Chlorine Residuals
Mike Ricks
April 17, 2012
• Filter Media Effectiveness
• Problems of less Efficient Media
• Options
• Problems with Organics / Algae
• Treatments
1
4/2/2012
• Trouble with short Filter runs
• Trouble with Clogged Under drains
• Trouble with mixing of my media layers
• Trouble with Media “Growth”
• Trouble with Channeling, “Mudballs”, and cementing
• Trouble with increase in turbidity & High Head loss
• Trouble with iron still coming through the filter
• Trouble with too little time and money
What we all Want
To go from This
To This
2
4/2/2012
Fe/Mn
Mn
Mn/Fe
Mn/CaCO3
Clean
CaCO3 Cake
CaCO3/Fe
Iron Bacteria
CaCO3
3
4/2/2012
Media Density
120
Before
Aftfer
100
102
100
Nominal
#/ft3
80
60
63
58
52
50
40
20
0
Anthracite
Sand
Media Distribution Top 12”
”
% Volume
80
Sand
60
53
50
72
Anthracite
70
47
40
28
30
20
10
0
Before
After
4
4/2/2012
Filter Media Effectiveness
Operators Typically
Adjust their
procedures to
compensate for
this degradation of
their media
100
90
80
70
60
50
Filter Media Effectiveness
40
30
20
10
0
Year 1
Year 2
Year 3
Year 4
Year 5
Year 6
Year 7
Year 8
Year 9
Year 10
Filter Media Effectiveness
No Cleaning 100
Shorter Filter Runs
Increase Fe & Mn levels
Turbidity Breakthrough
Uneven Backwash
High Starting Head Loss
90
80
70
60
50
40
30
20
10
0
Year 1
Year 2
Year 3
Year 4
Year 5
Year 6
Year 7
Year 8
Year 9
Year 10
5
4/2/2012
Filter Media Effectiveness
100
90
80
70
60
50
Filter Media Effectiveness
40
30
20
10
0
Year 1
Year 2
Year 3
Year 4
Year 5
Year 6
Issues
• Bio- Mass Increases the size of
media particles
•
Year 7
Year 8
Year 9 Year 10
Anthracite
Get degradation of capacity and
filtration properties of media
• Reduction in uniformity of media
particles
•
Alters flow and degrades filter
performance
• Deposits Mask Angularity of the
Media
•
Sharp edges needed to create
turbulent flow – deposits take this
away by covering edges
6
4/2/2012
Issues
Cleaned
• Masking of the adsorptive surfaces
•
Deposits occupy the bonding sites
that remove contaminants
• Altering of the Density of the media
due to build-up
•
Lose transition zones and don’t
settle in proper spots after
backwash
• Decrease Effective Depth of media
•
Media “growth” leads media
washout during backwash
• Get Mudballs, Cementing, &
Channeling
•
U–G–L-Y
water channels around clumps and
slabs and are not filtered
• Block Under drains and Direct
Media Support
•
Result in high head pressure during
filtration and high backwash
pressures during backwash
• Degrades backwash
effectiveness and damages
under drains
• Operators backwash to remove
deposits on the media
•
However, small deposits always
remain and build up over time
7
4/2/2012
• Short or Declining Filter run times
•
High Starting head loss
•
Turbidity Break through
Time to Fix It
• Uneven Backwash
• High backwash pressures
•
Loss of media
•
High pressure can lead a complete
Re-Build of the entire Filter
• Can See Media Growth
• Iron & Manganese levels in
finished water
• Call your Engineer or Well Driller for Filter
Rehabilitation and media replacement
• Go to the Town board and ask for a rate increase
• Hire more people or re-assign other peoples duties to
help with filters
• Seek alternatives to replacement
8
4/2/2012
• Drain Filter
• Get sample from anthracite and sand
• Get multiple samples from different areas
of filters
• “Z” Pattern
WSU Cleaing Filter Information Sheet
City / Utility:
Treatment Plant:
Contact Person:
Address:
City:
Phone - Office
E-mail
Title:
State:
Phone -Cell
Fax:
Zip:
Filter Type & other Basics
Filter Manufacturer and Model #
Gravity & number
Pressure Vessel & number
Concrete:
Steel:
Vertical:
Horizontal:
Package Plant
Aerolater
Others
Location:
Indoors:
Outdoors:
# offiline at once
Core Sample taken from Filter #
Size:
Length (feet)
Width:
Height:
Diameter:
Media Depth (inches)
Anthracite
Sand
Greensand
Gravel
Last Year Media Exchanged:
Chemically Cleaned:
9
4/2/2012
• Lab Report is a Must
•
•
•
•
Not the “Hand Test”
8-10 Page report
• Will do a Sieve Analysis
Shows what deposits have built up
Shows how much can be removed
• Which chemical blend is most
efficient
Shows Expected benefits from a good
cleaning
• Even if you do Nothing – this is a
great thing for your file and decision
making progress
•
Great to show Town Board, Mayor, etc
on condition of Filters and when
something needs to go into the budget
10
4/2/2012
Low /
Acceptable
Moderate
Significant
High
Severe
Recommended Treatment (per Filter)
Will Depend on make-up of mineral deposits
Primarily Iron and Manganese and magnesium
Blended MC – 444
Primarily lime, hard water scale deposits and calcium
Blended MC – 477
Many facilities need a combination
Also need CA-500 as a catalyst
Often need a neutralizer
11
4/2/2012
Reduced Head Loss
Reduced Effluent Turbidity
Improved Media Stratification
Longer Filter Runs
Improved Backwash Flow
Reduced Chlorine Demand
Removal of Mudballs
Prevent/Reverse Cementing
Cleaning of Underdrain
Extended Media Lifetime
Anthracite Untreated
x
Likely
x
x
x
x
Anthracite Treated
12
4/2/2012
Sand Untreated
Sand Treated
Sand Untreated
Sand Treated
13
4/2/2012
Green Sand
Untreated
Green Sand Treated
14
4/2/2012
15
4/2/2012
Before
Cleaning/After
Cleaning
Small Deposits
Clean Media
The orange and black on the Before picture are
the deposits. The black particles in the After
picture are the black sand particles.
16
4/2/2012
• “Hide” in under drains
• Never go away
• In source water
• Can be heavier in corners and under
drains than in media itself
• Can be removed with cleaning
17
4/2/2012
Replacement
Clean
• $30 - $90 per
Cubic Foot
• Usually $10-$30
per cubic foot
• May take 3-5 days
per filter
• 1-2 days per filter
to clean
• Under drains, and
filter walls are not
cleaned
• Will clean Under
drains, support
gravel, & filter walls
• 100% new media
• like new media
Replaced
• $26,500 $48 per cubic
foot
• New Media and gravel
$8,000 including
Freight
• Labor $17,000
• $1,500 unexpected
welding needed
Cleaned Filter –Est.
• $13,250 to clean $24
per cubic foot
• May be cleaned every
2-5 years for $6 9,000
• With cleaning will
likely go 20 years +
before replacement
• Under drains, and filter
walls not cleaned
18
4/2/2012
Replacement
• Initial Replacement and
Replaced every 3-4 years
(3% inflation)
• Year 1 $26,500
• Year 5 $29,826
• Year 8 $32,592
• Year 12 $36,682
• Year 15 $40,084
• $175,062
Replacement
• Initial Replacement and
replaced every 7 years
(3% inflation)
• Year 1 $26,500
• Year 8 $ 32,592
• Year 15 $40,084
• $99,175 Takes you
through Year 15
Cleaning –
50% of Replacement
• 1st Cleaning and
subsequently yearly
cleanings (3% inflation)
• Year 1 $13,250
• Year 2 $6,824
• Etc. thru Year 15
$10,021
• $123,218
Cleaning
• Initial cleaning and
cleaned every 3 years
(3% inflation)
• Year 1 $13,250
• Year 4 $7,239
• Year 7 $7,910
• Year 10 $8,644
• Year 13 $9,446
• Year 16 $10.322
• $50,186
Takes you
through Year 16
19
4/2/2012
Replacement
Cleaning
• Initial Replacement and
replaced every 15
years (3% inflation)
• Year 1 $26,500
• Year 15 $40 084
• Initial cleaning and
cleaned every 4 years
(3% inflation)
• Year 1 $13,250
• Year 5 $7,457
• Year 10 $8,644
• Year 15 $10,021
• $66,584
• $32,746
Replacement
• Large labor costs and
long down time
• Difficulty in gaining
access to filters
• Greensand up $100
cubic foot and may wait
6 months
Cleaning
• Can be too much build-up to
clean efficiently
• Some plants have issues with
getting rid of backwash
• Will do more often than
replacement
• No chance to repair under
drains
• GAC Media can be cleaned,
but not regenerated
20
4/2/2012
• More water use during backwash
• More Electricity used
• More labor used because of more frequent
backwash
• Added chemical cost
• More chlorine / phosphate, etc. needed post filter
• Potentially more Bio-film growth in Towers and
distribution system
• Replace ?
• Expensive
• New
• Still other issues potentially unattended
• Clean
• Generally less expensive
• Like New
• Cleans under drains, etc
21
4/2/2012
• Depending upon build-up
• Clean every 1, 2, 3, or 4 years
• What if there is no money to replace or fully
clean?
• Can partially clean to maintain usage and stay ahead of build-up
• Actually a good way to save money
• If current filters are in severe shape
• Replace
• Get on routine cleaning
• Take numbers of years to get bad and divide by 60% to decide how often
to clean
Before Cleaning
• Iron out of Filter – 2.0 +
• Chlorine rotameter was set at
18 pounds per
• Backwash contained high
levels of dirty water
• Full of mudballs and slime
• Residential Complaints of
Dirty Water
22
4/2/2012
• Iron out of Filter – .1
• Chlorine rotameter was set now at 13 – chlorine
demand in filter decreased
• Backwash contained now little or no iron after
backwash
• Now no slime and mudballs
• Improved water quality fewer complaints less
dirty water
• Best One – Residents Happier – Supt. Sleeps
better at night!
Reducing TOCs, DBPs,
and Improving
Chlorine Residuals
23
4/2/2012
Where are the
Biofilms and
Organics?
At the Reservoir
In the Wells
In the water mains from
wells to Plant
At the Aerators
In the Treatment Plant
In the Basins and
Clearwells
In the Towers
In the Distribution
System
What is a Biofilm?
• Adhere to surface and
grow
• They Feed
Themselves
• Live off bacteria in
the water
• Many types
• Bacteria
• Protozoa
• Fungi
• algae
• Cover their “Colony” in a
protective polysaccharide
shield
24
4/2/2012
The Extracellular Matrix
• Biofilm is held together by EPS
• Extracellular polymeric substance
• I say “polysaccharide shield”
• Protects the biofilms cells
• Resistance to chemicals, detergents, and
antibiotics
“Indicators” of Bioflim
• High HPC
• High Total Coliforms
• High TOC
• High AOC
• High BDOC
• High DBPs
• Low Chlorine Residuals
25
4/2/2012
What is an organic?
TOC – Total Organic
Carbon
• Measures total carbon
and inorganic carbon
• Decaying Vegetation
• Bacterial growth
• Metabolic activities of
living organisms
• Chemicals
NOM – Natural Organic Matters
• Part of TOC
• Humic Acid
• Fulvic acid
• Amines & urea
• React with Chlorine
compounds to form
Disinfection By Products
• Fertilizers
26
4/2/2012
Why are biofilms and organics
in all these places?
Biofilms
Organics
• Aqueous Environment
• Naturally occurring
• Lots of nutrients
• Synthetics
• Organics
• Detergents
• Minerals
• Pesticides
• Added chemicals
• Fertilizers
• In hard to reach spots
• Filters
• Towers
• Correlation between high
TOCs and biofilm
development
• Distribution systems
What are the Negative
effects on your System?
• Increase in Chemicals
• Increase DBPs
• TTHMs
• HAAs
• Low to zero Chlorine residuals
• Burden on your Equipment
• Aerators
• Filters
• Wells
27
4/2/2012
Is there a simple test?
“Grab” sample
• Biofilm may detach
individually or in
clumps
• Testy may not indicate
biofilms
• Dynamic and respond
to their environment
What happens?
• Biofilms over time
survive
• Bacteria will often die
quickly without biofilm
• Extra Cellular Matrix
will may produce
catalase to breakdown
chemicals
28
4/2/2012
More Issues
• Nitrification
• Taste and Odor problems
• Internal Corrosion and Loss of Flow due to
biofilm deposition
• Excessively High Applied Chlorine Rates
• Dirty Water Complaints
What Should I do?
• Suggestion from the Experts
• Montana State University
• “Control of these biofilms is difficult. Disinfection
alone is usually ineffective. Reduction of organic
matter, improved disinfection, and the
implementation of corrosion control in unlined iron
pipes are present, or a combination of these
methods is helpful in controlling distribution
system biofilms.” - Camper, A.K MSU
29
4/2/2012
Algae - Isn’t
this Lovely?
Geeseweed?
What Is Algae?
True Algae are essentially Plants! – no toxins
Cyanobacteria – release toxinsa
• Cyanobacteria are a sub-category of bacteria that contain
photosynthetic pigments, and therefore produce energy
through photosynthesis
• Previously known as blue-green
algae.
30
4/2/2012
Cyanobacteria are very resilient and adaptive,
existing virtually anywhere moisture can be found
• Can be unicellular or
colony-forming in
nature. Colonies can
be in the form of
filaments, biofilms, or
‘ball type’ structures
Cyanobacteria common in Illinois:
•
Anabaena
•
Aphanizomenon
31
4/2/2012
… Cyanotoxins
• How cyanobacteria produce cyanotoxins is not
fully understood
• After a cyanobacteria dies, its cell wall decays
(lyses) and releases its accumulated toxins into a
water supply
• Cyanotoxins can accumulate in other aquatic life
(fish, shellfish)
• Exposure to cyanotoxins can occur through direct
contact or accidental ingestion
What a cyanobacterial
bloom looks like
• Foam, scum, or mats
• May be blue, bright green, brown, or red and may look
like paint floating on the water.
St. John’s River
Charles River
32
4/2/2012
Multiplying Cyanobacteria
• Cause blooms, & during blooms, water can become hypoxic,
adversely affecting other aquatic life
• Cyanobacteria also produce Taste and odor issues
Health concerns in mammals
(including humans) include:
• Hepatotoxins (liver function)
• Neurotoxins (nervous system functions)
• Possible link to ALS (Lou Gehrig’s Disease)
• Cytotoxins (damages individual cells)
• Gastrointestinal distress (nausea, diarrhea)
• Pruritic Skin Reactions (itching, rashes)
33
4/2/2012
And No fun
Headlines No One
wants to see
Published: May 2, 2010
• Ft. Wayne Journal Gazette
• Algae bloom
fouls tap water
in Indianapolis,
Muncie
• July 2, 2010
• Dayton Daily News
• Grand Lake St.
Marys 'dying'
from toxic algae
July 2011
• AssocTimes-Union –
• Blue-green algae
found in southern
Kosciusko
34
4/2/2012
Simple Truths
• When Algae grows, it increases pH
• The increase pH forms carbonate
• This leads to –
•
•
•
•
•
Increase in TOC
Release of algae toxins
Increase in DBP precursors
Shorter filter runs
Taste and odor issues
What Can you Do?
• Test
• Notification of Illinois EPA
• Treatment
35
4/2/2012
Testing
Taste and Odor
• Threshold Odor Test
• Done by humans –water
diluted until no odor is
detectible
• Flavor Profile Analysis
• Determines which tastes are
causing the odor
Microcystin – LR
• Collecting water samples:
• When practical, sample is
collected 1 ft. below the
water surface
• During blooms, surface
samples (both water and
biomass) are also tested
What the Testing
will Tell You
• Algae count
• Toxin concentration level
• Algae Identification
• pH & Turbidity
36
4/2/2012
Algal Toxin
Thresholds
Threshold
(ug/L)
Microcystin
Anatoxin-a
Cylindrospermopsin
Saxotoxin
Do Not
Drink
1
20
1
0.2
Do Not Use
20
300
20
3
Potential Labs (Ohio
EPA)
Celina Utilitiesi
GreenWater Labst
Mike Sudman, Jr.
Palatka, FL
419-586-2270
877-869-2542
cwtpsupt@bright.net
info@greenwaterlab.com
BSA Environmental
Dr. Judy Westrick
Beachwood, OH
Lake Superior State
216-765-0582
906-635-2165
j.beaver@bsaenv.com
jwestrick@Lssu.edu
37
4/2/2012
Other “Headlines” No
One wants to see
• TTHMs – MCL 80
• HAAs – MCL 60
TOC Reduction
Chart
Raw TOC
2.0 – 4.0
4.0 – 8.0
8.0 +
0-60
35%
45%
50%
Raw Alkalinity
60-120
25%
35%
40%
120 +
15%
25%
30%
38
4/2/2012
$ your Village Manager
doesn’t want to see
• High Dollars being spent on Permanganate
• High Dollars spent on Powdered Activated
Carbon
• High Dollars spent on Chlorine
• You’re treating the Reservoir again with
Copper Sulfate
What can you Do?
• Optimize Plant process
• Chlorine
• T & O associated with color and turbidity or floating algae,
adjustments to coagulation, sedimentation, and filtration often
work
• Air Stripping
• Oxidation
• Mechanical
• Chemically – more later
39
4/2/2012
Some Suggestions
• Ohio EPA White Paper
• June 9, 2011
• Through the Treatment Train
Source Water
Treatment
• Watershed Protection
• Reduce Nutrient Load
• Reduce or eliminate contaminants
• Algaecides
• Earth Tec
• Copper Sulfate
• Treat Early
• Potential for toxin release is low
• If toxins released, easier to remove
• Low pH
40
4/2/2012
Common
Treatments
Copper Sulfate
• Copper Sulfate
• Apply directly to Lake,
Pond, or reservoir
• Typically need “certified
applicators”
• GPS Devices specially
designed boats
• Drag burlap bag around
• Inactivates Algae
• Drops quickly to bottom
of water basin
Earth Tec vs Copper
Sulfate in Reservoirs
• Self- Disperses
• 25 ft. horizontally & 8
ft. vertically per hour
• 99.9 % Active Cu++ ion
• More copper available
to attack the problem
41
4/2/2012
Pictures you are looking for
Conventional
Treatments
• Coagulation
If these are good
• Flocculation
• Sedimentation
Then, these work well
• Filtration
• Disinfection
42
4/2/2012
Coagulation and
Flocculation
• Good Preparatory step for removal
• Guidelines
• Control Targets for turbidity, DOCs, etc.
• Do Jar tests to allow for differences in water quality
• Minimize Flocculator speeds where possible
• May have to increase Sedimentation sludge withdrawal
cycles
• Want to avoid dissolved toxin release from decaying cells
Chlorine
• Are you sure you want to chlorinate before filter
influent?
• Can Lyse blue-green algae cells and increase
dissolved toxins
• Proper application very good for many toxins
• Does not effectively eliminate anatoxin-a
• Chloramines are not effective for toxin destruction
43
4/2/2012
Filters
• May increase backwash frequency
• Avoid long storage times and decay inside filter bed
• Check filter effluent for cell breakthrough
• Minimize hydraulic disturbances
• Consider Cleaning in Place procedure to
remove deposits to improve filter performance
• Less expensive than filter replacement
Activated Carbon
• Granular Activated Carbon (GAC)
• Absorb toxins
• Can be used as biological process by allowing
bacterial growth on GAC media
• Effectiveness influenced by type of toxins and
competing Natural Organic Matter (NOM)
• Consider optimizing reactivation frequency based
on occurrence of blue-green algae
• Life span 2 months to 1 year
44
4/2/2012
Powder Activated
Carbon
• Can be used periodically or seasonally
• Can be added prior to coagulation and removed in
settling tanks, or added to settling tanks and removed in
filters
• Need adequate detention time – 60 minutes
• Many types
• Coal - saxitoxins
• Wood – micocystins & cylinsrospermopsin
• Coconut - saxitoxins
Oxidation
• Preoxidation
• Not recommended by Ohio EPA – not sure of Illinois
• Will lyse blue-green algae cells and release their toxins
• If Pre-Oxidation is necessary for adequate turbidity and /
or organic carbon removal consider weaker oxidant such
potassium permanganate
• Use PAC to remove toxins released by permanganate
• Oxidants may increase Disinfection Byproducts
• Consider non-oxidizing organic removal programs –
EarthTec – (Often Reduces Disinfection byproducts and
TOCs)
45
4/2/2012
Chlorine
• Reactive Against
• Microcystins
• Cylindrospermopsin
• Saxitoxins – to a lesser extent
• Not reactive vs. anatoxin –a
• Reactivity influenced by pH and presence of NOM
• Need more Contact time depending on water quality
Chloramine &
chlorine dioxide
• Not reactive vs. the four toxins
• Need very high doses and long contact
time with chloramines effective vs.
microcystins, but doses are not realistic
• Effective doses of chlorine dioxide cause
problems with chlorite and chlorate
46
4/2/2012
Potassium
Permanganate
• Reactive vs.
• Microcystins
• Anatoxin-a
• Cylindrospermopsin – possibly
• Not Oxidized
• saxitoxin
Ozone
• Reactive vs.
• Microcystins
• Anatoxin-a
• Cylindrospermopsin
• Least susceptible
• Saxitoxin
• 20% of microcystins
• Hydrogen Peroxide with Ozone better than Ozone
alone
47
4/2/2012
UV
• With Hydrogen Peroxide is effective
• However, increased power requirement for advanced
oxidation is many times greater than required for UV
levels in water disinfection
Earth Tec - Reducer
• Removes precursors to •
•
•
•
Microcystins
Cylindrospermopsin
Anatoxin –a
saxitoxin
• No lysing of cell
• Often Replaces Permanganate in treatment train
• Often reduces feed rate of PAC and chlorine
• Reduces DBPs
• Clears basins of algae
48
4/2/2012
Membrane Filtration
-others
• Should remove blue-green algae effectively
• Large pore size allows extracellular toxins to pass
through
• Cells may rupture
• Extent depends on pressure and time between
backwashes
• Cells can hard to remove from membrane
• Submerged systems may be better than pressurized
systems
Biological
Filtration
• Will remove/ inactivate
• Microcystins
• Cylindrospermopsin
• Saxitoxin may transform to more potent toxin
• Often difficult to manage – best used a “polishing
step” following another primary removal treatment
49
4/2/2012
Residual Handling
issues
• Modify Backwash
• Modify sludge recycling process
• Too much of either process can cause unruptured cells
to lyse
• Discontinue during Bloom?
• Remove sludge from sedimentation basins
A Couple of Case
Studies
• Gateway Regional
50
4/2/2012
Gateway Regional –
Case Study
• New Program Started - May 3, 2010
2009 - Numbers
• TOC Reductions
July
44%
3rd
4th
Qtr.
Qtr.
August
43%
Sept.
52%
THMs
75
48
Oct.
42%
Nov.
50%
HAAs
60
33
Gateway Regional –
Case Study
• New Program Started - May 3, 2010
2010 - Numbers
• TOC Reductions
July
53%
3rd
4th
Qtr.
Qtr.
August
60%
THMs
40
33
Sept.
44%
Oct.
52%
Nov.
64%
HAAs
19
17
51
4/2/2012
Gateway Regional –
Case Study
• New Program Started - May 3, 2010
2011 - Numbers
• TOC Reductions
July
?
3rd
4th
Qtr.
Qtr.
August
?
THMs
41
29
Sept.
?
Oct.
?
Nov.
?
HAAs
18
17
Gateway Regional –
Case Study
• Other Benefits
• PAC reduced form 6-7 ppm to 2-3 ppm
• Previous Taste and odor issues gone
• Eliminated algae in clarifier troughs
• Reduced Chlorine feed rate
52
4/2/2012
Salem, IL– Case Study
• New Program Started – April 2010
2009 – Numbers – Avg. 4 sampling sites
1st
Qtr.
Qtr.
rd
3 Qtr.
4th Qtr.
2nd
THMs
62
60
64
82
HAAs
38
35
15
54
Salem, IL– Case Study
• New Program Started – April 2010
2010 – Numbers – Avg. 4 sampling sites
1st
Qtr.
Qtr.
rd
3 Qtr.
4th Qtr.
2nd
THMs
43
84
15
25
HAAs
42
31
7 - New Program rolling
8
53
4/2/2012
Salem, IL– Case Study
• New Program Started – April 2010
2011 – Numbers – Avg. 4 sampling sites
1st
Qtr.
Qtr.
rd
3 Qtr.
4th Qtr.
2nd
THMs
29
62
83
41
HAAs
24
40
23 - Algae Bloom
16
At The Well &
Mains
Work with your
well company
When to Clean
80% of original
capacity
Coliforms
presence
How to Clean
Chemicals
Super Chlorinate
Aqua Gard
EarthTec
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4/2/2012
Iron Bacteria
• Reddish or Brown slimy
masses
• Often produce “oily” sheen
• Odors
• Rotten eggs, fuel oil,
cucumbers, or sewage
• Corrosion of Equipment
• Reduction in well yields
• Increased infestations of
other types of bacteria
• Coliforms
• Sulfur reducing bacteria
At The Aerator
Maintenance
Iron Bacteria
Dirty
Labor
Issues
Increased Backwash of
Softeners / Filters
Burden on Filters
Excess Iron / Mn to
come through
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4/2/2012
Pipe After Aerator
Case History - Atlanta, IL
• Dirty water Complaints
• Aerator Cleaning hours, slimy gooey mess
5 guys, 8
• Softeners had slime and needed
backwashing 3 times a day
• No Chlorine Residuals on edge of town
• Flushing took 3 weeks – 20 minutes a
hydrant
• Salt for Softeners ordered 14 times a
year
• $3,200 an order
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4/2/2012
Case History - Atlanta, IL
• “I don’t know what the hell you’re doing, but keep it up”
• Took 2 summer help kids 2-3 hours and they weren’t even
dirty
• Backwash softeners once a day – Regenerate at 32,000
instead of 25,000 – crystal clear water
• No Slime on top of softeners
• Salt Order down 3 times in 6 months
Atlanta, IL
• Chlorine Residual 0.05 to 0.10 at edge of town
• Flushing took 4 days – 10 minutes a hydrant
• Iron levels were .6 - .8 - now .18
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4/2/2012
In Basins & Clear wells
Biofilms
Organics
Primarily Algae - SW
• Increase DBPs
• Extra $ on
Permanganate,
PAC, and chlorine
• Time
• “Eats” Chlorine
• Low residuals
• Increase DBPs
Short Case Study –
Speedway, IN
• Algae Growth in Sedimentation Basins
• Engineers recommended $500,000+ cover
for basins
• Chlorine Fed at beginning of basins
• Heavy build up on sides of wall, dredging
chains, and dark green color to water
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4/2/2012
Short Case Study –
Speedway, IN
• Significantly less Algae Growth in Basins
• Applying for permanent permit
• Less Chlorine Fed at beginning of basins
• No Heavy build up on sides of wall,
dredging chains, and dark green color to
water
In the Distribution System
• Disappearing Chlorine
residuals
• Higher Applied Chlorine
Rates to achieve the same
residuals
• Dirty Water complaints
• Slime on meters
• Slimy Toilet tanks
• Internal Corrosion
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4/2/2012
In the Distribution System
• Attack from the plant or from a booster station
• Use Deposit Control Agents
• Chloramines
• Phosphates
• Go after polysaccharide shield of biofilm
• Must be on a flushing program
• Automatic Flushers
Corrosion
• Stainless Steel
• Microorganisms modify
disposition of metals
• Detach individually or in
clumps
• Migrate across surfaces
• 10 fold more biofilm on
metals vs. plastic
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4/2/2012
Phosphate
Phosphate #1
Price per gallon
% phosphate
$12.00
18%
Phosphate #2
Price per gallon
$12.00
% phosphate
35%
weight in lbs
10.5
weight in lbs.
11.5
price per wet lb
$1.14
price per wet lb
$1.04
price per lb of Phosphate $6.35
price per lb of Phosphate
$2.98
pounds used per day
46.33
pounds used per day
23.83
Gallons used per day
4.41
Gallons used per day
2.07
Cost per day
$52.95
Cost per day$24.86
Two Ways to Chemically Approach
Biofilm
1. Periodically, as a System Cleaning Agent.
•
Feed in conjunction with a System Flush
2. Continuously, after system cleaning lower dosage to
small maintenance level
•
•
Again, system cleaning should be done in
conjunction with system flush
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4/2/2012
New Product
• Can penetrate slime layers, cell walls and protective
layers of micro-organisms and effectively kills
pathogens as a result. The micro-organisms will
either die or suffer from reproductive failures.
Summary
• Biofilms and Organics may in every part of your system
• Each Area may take a different approach
• Often a combination of approaches is the best solution
• Consultants, engineers, well drillers, and lab
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4/2/2012
Summary
• Blue-Green Algae is cyanobacteria
• Releases Toxins
• Not Easy to remove
• One solutions may cause other issues
• Consider new options
Questions
Mark McKee-
(765) 719-2956
Dan Helm-
(309) 236-7469
John Reynhout
(815) 693-3694
Troy Mott
(309) 824-9975
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