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Biological Process of Wastewater
And Algae Control
Dick MarcheskiMaryland Biochemical Co
Good Settling = Good Floc
▪Floc - Biomass woven into a particle by a combination of
filaments, inert material and exopolymers produced by
bacteria in declining growth phase
The goal of wastewater treatment is to produce this…
A clean effluent
AVG. floc size150-600 microns
2
3
What we want!!
Unfortunately the reality
Mixing tankprior to aeration basin
Primary clarifier
Settling basin for ASB system
Nocardia foam
Foam on aeration tank
Bulking sludge
Settling issues5
Filaments
Denitrification
Bacteria
Primary decomposers of influent organic
waste.
Single cell microorganisms
Dependant on environmental conditions for
peak performance
Reproduction time in PURE
culture:
Bacillus sp. 20-30 minutes
Nitrifiers 12-48 hours
Methanogens 10-30 days
Spore forming Bacteria
Free Motile Bacteria
1. A microorganism must exist that can degrade the organics
2. The microbe must produce an enzyme that reacts with the organics
3. The microbe can get to the organics (mixing)
4. Requirements for metabolism are met (Biological Parameters):
• Oxygen (electron acceptor), macronutrients, micronutrients, pH, temperature.
5. Growth occurs (new microbes).
The following things must happen in order to degrade organics:
Operators aim to control this process
400X
Wastewater Biomass
7200X
Growth Pressures Affecting BioMass
Inert material
Operator
Temperature
SRT
pH
Soluble Organics
ToxinsDissolved Oxygen
Proper Biological Parameters are necessary for cell reproduction and function
pH
Dissolved Oxygen
Retention Time
Water temperature
Mixing
Nutrients N&P
Reproducing BioMass
Carbon Source (food)
• Range 6.5-8.5 Optimum 7.5
• High or Low pH – denatures enzymes
• 1.0 pH swing within 24 hours could be inhibitive pH
• Saturated oxygen as DO is the preferred source of respiration for the biomass
• Alternatives are nitrate and sulfate
• Range 0.5 – 3.0 Optimum 2.0
Dissolved Oxygen
• Sufficient time needed for organic degradation, varies on the components of the influent waste stream
Hydraulic Retention Time
Biological Parameters
• Every organism has a minimum, optimum and maximum growth temperature
• Drastic temperature swings could be inhibitive
Water Temperature
• Microorganisms are not hunters
• They absorb organics and oxygen in the water column through mixing or recirculation
Mixing
• Macronutrients: Nitrogen & Phosphorus
• Micronutrients: Minerals, Vitamins and Amino Acids
Nutrients
Biological Parameters
Biological Parameters
•MLSS vs MLVSSReproducing BioMass
•Waste streamCarbon Source
Monitoring the Biological Process
Operator
30 Minute Settling
Microscopic Exams
Monitoring the biomass through settling tests and microscopic
exams in addition to other daily monitoring, can give the operator a
more thorough explanation of plant performance
Aeration basin
Home of “active biomass”
Take the sample here!!
Find Funny Hungry Bugs
•Floc
•Size, shape, density
•Filaments
•Abundance, type
•Higher life forms
•Presence, abundance, diversity
•Bulk water
•Clean, containing inerts or
bacteria
Microscopic Exams
Floc
Size Density
100X magnification 400X magnification
Shape
400X magnification
All photos at 100X magnification
GOODNOT TO GOOD
GOOD*
NOT GOOD
OKAY BUT NOT GOOD GOOD/NOT GOOD
Filaments
Location of the filaments helps to determine the potential cause
ExtendingGrowth pressure change
Bulk waterPossibly substrate related
Examples of Abundance Ratings
3
4
5
Manual on the Causes and Control of Activated Sludge Bulking, Foaming, and Other Solids Separation Problems 3rd edition Jenkins, Richard, Daigger Lewis Publishers
1
Rating
0
1
2
3
4
5
6
Term
None
Few
Some
Common
Very Common
Abundant
Excessive
Description
No filamentous organisms present
Filaments present but only in
occasional floc particles
Filaments present in most, but not all
floc particles
Filaments observed in all particles at
low density (0-5 filament per floc)
Filaments observed in all particles at
medium density (5-20 filaments per
floc)
Filaments observed in all particles at
high density (>20 filaments per floc)
Appears more filamentous organisms
than floc particles and/or abundant
filamentous growth in the bulk solution
Adverse Settleability
Experienced?
No
No
No
If significant interfloc bridging
or open floc formation
Usually
Yes
Yes
Filament environment
▪Low Dissolved Oxygen (D.O.)
▪Low Nutrients (N and P)
▪Low Food to Mass ratio (F/M) or High F/M
▪Septicity/Organic acids
▪Readily degradable substrate
▪ Manual on the Causes and Control of Activated Sludge Bulking, Foaming, and Other Solids Separation Problems 3rd edition Jenkins, Richard, Daigger LewisPublishers
Nocardia (gram stain G+) Type 0041
Thiothrix II (rosettes)
Filament examples
N. Limicola III (dead)
Jenkins Manual- 22 filamentsEikelboom- 87 Industrial filaments
Microscopic ExamsHigher Life Forms
Protozoa & MetazoaLook for presence, abundance, diversity
Suctoria
Microscopic ExamsBulk Water – Is it clean or does it contain inert material and/or
bacteria?
Poor Settling
Monitoring Settlingwith 30 minute settling test
30 Minute Settling
Shock Recovery
Inflow
or
Infiltration
Organic Shock
BOD, pH or temperature change,
Loss of Nitrification
Increasing the activity
of bacteria that decompose
organic pollutants
*http://www.everythingbio.com
Bioaugmentation
Manufacturing Process
Natural Occurring Bacteria
Petri Dish
Shake Flasks Fermentation Vats
Plant Start upHydraulic Washout or Organic Shock
Recovery
Filament Control/Recovery
Fat, Oil & Grease in the Collection
System and Plant
Low DO or oxygen availability
Aerobic and Anaerobic
Digester Efficiency
FoamingNutrient Removal –
Nitrification and Denitrification
Hot/Cold Weather Operations
High Chlorine Demand
Odors in Collection System and Plant
including H2S
Industrial discharge
Applications where adding cultured organisms will help
Bioaugmentation
NOVOZYMES PRESENTATION17/12/201935
Wastewater lagoons
Advantages:
•Simple construction
• Low capital costs
• Simple operation
Disadvantages:
•Solids buildup
•Effluent quality
•Land area requirements
•Limited operational flexibility
Industries:
•Municipal
• Pulp & Paper
• Food processing
• Refineries
• Polishing ponds
• General industry
Treatment goals:
• Meet permit requirements
• Minimize environmental impact and risk
• Minimize costs
NOVOZYMES PRESENTATION17/12/201936
Novozymes BioSpikes®
A biological alternative to dredging
• Reduce dredging costs
• Improve system efficiency
Novozymes BioSpikes® at work
NOVOZYMES PRESENTATION17/12/201937
Microorganisms, nutrients, and enzymes permeate throughout the sludge layer
Novozymes BioSpikes® are dropped at the water’s surface and sink directly into the sludge layer
• Minimizes Volume• Improve sludge quality• Improves system efficiency
NOVOZYMES PRESENTATION17/12/201938
Cost savings
Alternative to dredging
• Reduces dredging frequency
• Defers immediate need for dredging
• Solids reduction becomes an ongoing maintenance budget item, instead of a one-time large expense
Minimizes dredging costs
• The less sludge in the lagoon, the lower the dredging cost
Optimizes lagoon system performance
• Improves operating capacity
• Increases hydraulic retention time
• Minimizes short circuiting
Resulting in cleaner water and better handling of load swings
NOVOZYMES PRESENTATION17/12/201939
System efficiency
Reducing sludge in a municipal lagoon
NOVOZYMES PRESENTATION40 12/17/2019
RESULTS•28% reduction of sludge levels
•26% of the total lagoon capacity recovered
•A $600,000 dredging project deferred
BACKGROUND• 2.5-hectare (6-acre) lagoon• 3.4 m (11 ft) deep• Sludge level ranged from
2.4 to 3.0 m (8 to 10 ft)• Concerns about treatment
capability and solids capture• Received dredging quote of
USD 600,000
NOVOZYMES PRESENTATION17/12/201941
Maintaining low sludge levels in a municipal lagoon
Application:
• Goal was to minimize sludge buildup
• 76 m3 (20,000 gal) per day flow
• 2.74 m (9 ft) deep
• 38% reduction in sludge level
• Remained 33% lower after seven months
Before treatment After treatment
Surface aeration – requires a lot of energy which can cost a lot of $$
RELIANT
The Lagoon Master
Sludge Activating Aerator
RELIANT
Out of Water In the Water
• Phase 1 large bubbles (1” to 2” diameter) push water ahead of them and form a blanket of bubbles and high velocity water moving along the surface.
• Phase 2 small bubbles (<1mm in diameter) provide high volumes of dissolved oxygen because they are kept under water by the Phase 1 bubbles and fast moving surface water and have at least 25’ of residence time.
RELIANT
FINE BUBBLES, UNABLE TO RISE ABOVE TURBULANCE OFCOARSE BUBBLE FLOW, FINALLY BREAKING THE SURFACE
QUIESCENT WATER FORCES TURBULANT SURFACE FLOWING WATERTO FALL UNTIL IT HITS THE SLUDGE ON THE BOTTOM. THISTURBULANCE ON THE BOTTOM BEGINS SLUDGE FLUIDIZATION
OPPOSITE SHORE TURNS WATER BACK TOWARDTHE INTAKE OF THE MODEL WQA, WHICH PULLS9 MILLION GALLONS OF WATER THROUGH ITSELFPER DAY. THIS FLOWING WATER COMPLETES THEFLUIDIZATION OF THE SLUDGE
RELIANT
RELIANT
Lagoon Master
RELIANT
A 60 acre facultative wastewater lagoon that is used by 4 towns in SE Louisiana
Baffles
Inlets for4 towns
RELIANT
Same lagoon only 6 months after installing a newSludge Activating Sub-surface Aerator
Baffles
Activated sludge4.77 acres
Single Lagoon Master
60 Acre Lagoon System
Boutte, LA
Sat photo datedNovember 2011
Lagoon Master installed September 2012
This Sat photo datedMarch 2013
Lagoon Master Aerator
Lagoon Master
Area of influence
Inlets to lagoon
Sludge islands
No islands
RELIANT
Lagoon Master Aerator
Can the Lagoon Master
operate in high icing areas?
• Yes – there are installations in Canada in the Maritimes, Ontario, and Manitoba
• The Ice Option is provided in 2 forms –
• For ice cover under 3 inches
• For much heavier icing conditions
RELIANT
Ice Option Characteristics
RELIANT
For Low Icing Applications
RELIANT
For High Ice Option Characteristics
RELIANT
By Fluidizing and Oxygenating,or , the Sludge
in the Lagoon -
• The indigenous bacteria in the lagoon can continually digest the organic components in the sludge – odor disappears
• All trapped nitrogen/ammonia and H2S in the sludge is oxidized and eliminated from the water
• The water quality is improved because the polluting gases have been released
RELIANT
And – because this is taking place all day, every day, the organic sludge in
your lagoon is reduced
AT THE SAME TIME
• You will reduce your aeration electricity requirement from 60% to 90%
• You will reduce your aeration maintenance requirements over 90%
• The lagoon’s water quality will improve and remain in compliance. ODOR is Controlled
• You will reduce the number of aerators per lagoonRELIANT
RELIANT
Hog Waste Lagoon – North Carolina
Owner’s sludge survey reported 6” of sludge eliminated in 70 days
Monmouth Park Race Track New Jersey
Problem – Excessive fecal coliform and E. coli
RELIANT
FecalColiform#/100ml
E. Coli#/100ml
June2010
760 2050
June2011
180-76%
70-97%
July2010
19000 12000
July 2011
175-99.9%
2-99.99%
August2010
22600 6933
August2011
165-99.95%
0-100%
Monmouth RacetrackNew Jersey
Sept 2010
Problem: High fecal coliformand E. coli counts, odor
Resolution: 1 Reliant Water Lagoon Master Aerator plus
300 lbs of augmentation per year
Lagoon Master installed April 2011April 2013
•Elimination of fecal coliform• Elimination of E. coli• Odors eliminated• No seasonal turnover• Clear water
Lagoon Master Aerator
Lagoon Master
RELIANT
Specific plant concerns?Questions?
www.marylandbiochemical.com