Emerging Technologies in Onsite Wastewater …...Emerging Technologies in Onsite Wastewater...
Transcript of Emerging Technologies in Onsite Wastewater …...Emerging Technologies in Onsite Wastewater...
Emerging Technologies in Onsite
Wastewater Treatment
Gordon Balch
Centre for Alternative Wastewater Treatment, Fleming College, Lindsay,
Alberta Onsite Wastewater Management Association: Convention and Trade Show
Friday, March 6th, 2015, Edmonton, Alberta
Overview Opportunities for Rural Growth through Sustainable Service
• Framework (Building Code)
• Advanced Treatment Systems
– domestic
– Customized (alternative systems)
• CAWT Testing
• Future Trends / Needs
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Ont. Building Code
Part 8: Sewage Systems
• Building code regulates a number of different
classes of onsite treatment systems
• Class 4 is most common and is intended to
minimize pathogens released into the
environment
– can include secondary and tertiary (advanced)
treatment systems located between septic tank
and leaching bed
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Advanced Treatment Systems
4
5
Advanced Treatment Systems
Advantages • provide the opportunity to service sites not suited for conventional septic systems
• Better treatment
• may extend the life of an existing leaching bed
• take up less room in the yard
• require mandatory maintenance (ensures the unit is functioning properly)
• may reduce nutrient output (depending on type)
Disadvantages • may be more expensive to purchase and install
• more expensive to operate (e.g. yearly electrical costs, media replacement)
• mechanical parts that can break down or need replacement
• requires mandatory maintenance (increases costs)
Conventional Septic System
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septic tank pipe
30-50% treatment in septic tank 50-70% treatment in soil
Pre-treatment Final Distribution and Soil Treatment Absorption trench or filter bed
SepticSmart 2010
advanced treatment unit
gravity or pump flow
Area Bed
pre-treatment tank*
stone
sand
pipe
native soil
saturated soil
Advanced Treatment System
7 SepticSmart 2010
Pre-treatment Final Distribution and Soil Treatment Shallow Buried Trench
10% treatment in soil 90% treatment in septic tank
Advanced Treatment Systems
Intent of ATS:
• To mitigate site impediments to installation (e.g.,
heavy clays, shallow soils, limited space, high
water table, etc.)
• To provide added protection (nutrient
abatement) to at-risk sites (e.g., nutrient
sensitive lakes, ground waters, etc.)
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Approval Criteria for ATS
Must meet performance criteria set out by
building code
– testing and certification by the NSF International
(U.S.-based) standard
– consideration of Ontario’s environmental/climatic
conditions
– evidence of in-field performance.
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Evaluation of ATS Technologies
• Treatment unit technologies were evaluated
by MMAH
• List of approved treatment units found in
Supplementary Standard SB-5 to the Building
Code
• All currently approved systems incorporate
microbial treatment and or physical filtration
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SB-5 (Ontario): Advanced Treatment
Units
Suspended Growth
• Aquarobic Canada
• Aqua Safe and Aqua Air
• Biocycle Aerated Wastewater System
• Clearstream Treatment Systems
• Norweco Singulair Treatment Systems
• Whitewater Treatment Systems
• WSB® Clean Treatment Systems
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SB-5 (Ontario): Advanced Treatment
Units
Attached Growth
• Bio-Microbics — FAST®Wastewater Treatment Systems
• Bionest Technologies Inc.
• Nayadic Wastewater Treatment Systems
• Rotordisk Wastewater Systems
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SB-5 (Ontario): Advanced Treatment
Units Synthetic Media Filter
• Orenco AdvanTex® Wastewater Treatment System
• Waterloo Biofilter Treatment Systems
Peat Filter
• Premier Tech Environment — Ecoflo Biofilter Treatment Systems
• Puraflo® Peat Fiber Biofilter Treatment Systems
Sand Filter
• Orenco Treatment Systems
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Alberta manufacturers/parent companies authorized to sell their
NSF 40 Class 1 Sewage Treatment Plants.
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Treatment Plant Manufacturer/Parent Company
AdvanTex Orenco Systems Inc.
Bionest Bionest Technologies Inc.
Aero-Tech Aero-Tech
Singulair Norweco Inc.
Singulair Norweco Inc.
Mo-Dad Acquired Wastewater Technologies, LLC
AdvanTex Orenco Systems Inc.
Singulair Norweco Inc.
Fast Bio-Microbics Inc.
Ecopod Pentair (formerly Delta Environmental Products)
Ecoflo Bioflo Premier Tech Technologies Limited
SludgeHammer SludgeHammer Group Ltd.
Singulair Norweco Inc.
Pro Flo Pro Flo Aerobic Systems, LP
Jet Bat Jet Inc.
Bionest Bionest Technologies Inc.
Waterloo Biofilter
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There are different configuration depending on the
wastewater constituents and desired treatment level
CANWEST tanks & ecological systems
Ltd. Surry, BC
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17
1
2
3
4
5
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1. Primary Clarification
2. Moving Bed Bioreactor
3. Aeration
4. Final Clarification
5. Sludge Return
6. Outlet
WSB® clean Septic System
CAN/BNQ 3680-600
• CAN/BNQ 3680-600, “Onsite Residential Wastewater Treatment Technologies” is the new national standard for testing wastewater residential treatment technologies.
• This standard will replace the current criteria for treatment units set out in the Ontario Building Code, and the list of treatment units found in Supplementary Standard SB-5 which are deemed to meet these Code requirements. [to be revoked Jan 1/17]
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Treatment Options Domestic
Conventional Septic Systems
Advanced Wastewater Treatment
• Microbial (suspended or fixed) ± aeration
• Physical filtration ± aeration
Alternative Constructed Wetlands
Engineered Bio Reactors (e.g., S-reducing Bacteria for Arsenic)
Sportive media for Phosphorus
Moving Bed Bio Reactors for Oxidized N
Ozone
UV
Hybridized nano-membranes with nanoparticles
others
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Specialized (site-specific)Treatment
Needs
• Complexity of waste stream is increasing
• Greater need for site specific treatment options
– reduce treatment burden on existing systems (e.g.,
high BOD from brewery industry)
– Meet industry specific needs (aquaculture, mining,
health care, etc.)
• Ozone, sulfur reducing bioreactors, hybridized
constructed wetlands, etc., all showing promise
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Enhanced Nitrogen Removal
(stationary fixed film)
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Anoxic Aerobic Clarifier
Denitrification Nitrification
+
BOD removal
Denitrification • 2.3 g BOD per g NO3-N
• 3.02 g organic matter per g NO3-N
• Heterotrophic bacteria for generation of carbon source
• Significant portion of BOD generally consumed during nitrification, leaving little for
denitrification
High in
BOD &
NH4
Return unconsumed Carbon
Moving Bed BioReactor
(MBBR)
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• Small foot
• Very efficient
• Up to 5Xs
biofilm
• Does require
pumps and
aeration
Phosphate Removal
adsorption, precipitation
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H2PO4- + Fe Fe
O
O
Fe
O
Fe
O P
O
O
H
O
H Adsorption (Fe, Al, Mn oxides)
Precipitation (Fe, Ca, Al phosphates)
Variety of Sources and Manufactures
• Blast furnace steel slag
• Oxide rich natural clays
• Manufactured oxides (Al, Fe, mixtures)
Phosphorous adsorptive media
for Stormwater runoff
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• Adsorptive media can also be used in advanced treatment systems (residential)
• Work is proceeding in looking at ways to incorporate and regenerate media
Mining Sector
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Arsenic Removal from Tailings Waters
Engineered wetland to
complex dissolved
Arsenic with Sulfur with
the use of bacteria
Use of sulfur reducing
bacteria
Agriculture Sector
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CUI2I – Agriculture Wastewaters • Greenhouse wastewaters rich in Cl-, SO4
2-, Na,+
K+, Ca++
• High in Nitrates and Sulfates
• Employ salt hyper-accumulating plants,
denitrification reactors (removing NO3 and
convert SO4 to H2S) College-University idea to innovation Grants
Aquaculture Sector
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Land Based fish farm • Solids
• Nutrients (N & P)
• Fish pathogens
Trickle Filters
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• High removal rate of
BOD, Nitrogen, TSS
• Aerobic and anaerobic
zones
• Food wastes,
aquaculture
applications (e.g.
winery wastes)
• Sewer by-laws
Advanced On-Site Treatment
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• Ozone
• Pressure differentials
• Poly-filter
• Granulated activated carbon
filter
• Nutrients (N & P)
• TSS
• BOD
• Pathogens
• PPCPs
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Overview of System
Off gas &
destruct
Results: Selected PPCPs (ppt)
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0 200 400 600 800 1000
Levonargestrel
Progesterone
Medroxyprogesterone
Aspartame
Diclofenac
Carbamazepine
Trimethoprim
Sulfamethoxazole
Influent Effluent
n.d.
n.d.
n.d.
n.d.
n.d.
n.d.
n.d.
Concentration (ng L-1) Mean ± SD
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Constructed Wetlands
• Man-made with specific design specifications
• Intended to treat domestic waste using natural processes – Filtration / sedimentation
– Microbial oxidation / transformation
– Chemical processes
– Adsorption / absorption
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Hybridized Constructed Wetlands
Flow = 40 m3/d; Inlet COD = 1000 mg/L & NH3 = 1000 mg /L
Each line consists of:
1. SFS-v (e.g.,VSSF) stage with a superficial peat layer to ensure odor remove, leachate pre-
oxidation and metals precipitation;
2. Two stage SFS-v in series for nitrification (add O2) and organic load removal (e.g., BOD);
3. Two stage SFS-h (e.g., HSSF) in series for denitrification (remove O2) and removal of persistent
organic compounds;
4. A stage FWS to complete the denitrification and the organic compounds removal and to
enhance the evapotranspiration;
5. A final detention pond to accumulate the effluent and enhance the evapotranspiration.
The system is designed to ensure high removal rates (>90-95% COD and NH3), and a good
reduction of the effluent due to evapotranspiration.
Future Trends (???)
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North America
Wastewater Infrastructure Deficit
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• Wastewater
infrastructure deficit in
2 Provinces and 8 US
states is $10 billion
• $90 billion needed in
next 10 y (2007) to
replace and upgrade
Canada wide
Great Lakes Commission – 2007 report
Aging municipal infrastructure
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When Bigger Isn’t Better: Decentralized Wastewater
Treatment Systems (On. Environ. Commissioner 2009)
• Small or rural communities in Ontario faced with:
– Increasing population
– Climate change
– Stricter environmental regulations
• A call for decentralized systems
Waste Generation from DWWT
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• 1980 USA census – 3.8 trillion L per year to vadose zone (US EPA 1987)
• 25-30% of households in USA are served by septic systems (Bremer & Harter 2012)
• 22% of Canadians utilize on-site systems (Richardson & Fulton 2009)
Septic system leachate represents the largest
unregulated source of wastewater
1st everything
(1,385 km diameter)
2nd groundwater, fresh
surface water
(272.8 km diameter)
3rd fresh water in lakes
and rivers
(56.2 km diameter) Source: Scientific American
Global
Water
Supply
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Cluster Systems
Cluster systems are generally used to collect
wastewater from a small cluster of homes
• Waste is transported to the
site of treatment via
alternative sewers
• The transported wastewater is
treated at either a
conventional treatment system
or receives pre-treatment prior
to soil absorption of the
pretreated effluent
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Final disposal to Wetland and
Drainfield
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Application of Cluster Systems
• There can be many reasons
to install a cluster systems
• Most often installed because
the land size of individual
properties is not large
enough to accommodate an
on-site system OR
• Because the financial cost
for construction of a
conventional treatment
plant is not feasible
Small rural areas
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Human Health
Concerns
• Methaemoglobinaemia
• Cancers (increased risk)
• Thyroid disruption
2013
May see a
greater emphasis
on removal of
Nitrates
Phosphorus ???
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• Phosphorous
not strongly
linked to human
health
• Most issues are
impacts to
surface waters
• Cyanobacteria ?
• Present
concerns are
focused on
agriculture,
stormwater, etc.
Concluding Remarks
• Demand for decentralized treatment likely to
increase
• Demand for specialized treatment to off-load
burden to centralized systems may increase
• May see greater need for advanced treatment
systems for Nitrate and Phosphorous in
relationship to source water protection
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Questions
“You cannot get through a single day without having an impact on the world
around you. What you do makes a difference, and you have to decide what
kind of difference you want to make.” — Jane Goodall
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native soil
advanced treatment
unit
pump
chamber pressure flow
pressure pipe and chamber
pre-treatment
tank*
Advanced treatment units use oxygen
to enhance treatment.
saturated soil
47
Advanced Treatment System
Pre-treatment Final Distribution and Soil Treatment Shallow Buried Trench
SepticSmart 2010
90% treatment in septic tank 10% treatment in soil
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Smaller foot print of advanced treatment
systems
conventional advanced
WSB Clean
Disposal Challenges
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• Regulatory oversight / requirements increasing
– post Walkerton
– Ont. Environ Protection Act, Ont. Clean Water Act, etc.
• Complexity of wastewater increasing
– Pharmaceuticals and personal care products
• Increasing number of wastewater sources
– Petroleum, agra-farms, aquaculture, etc.
• Treatment Costs Increasing