Experimental application of the ICW concept for examining various - - PowerPoint PPT Presentation

Experimental application of the ICW concept for examining various wastewater treatment.

• Dr. Caolan Harrington

Meso-scale ICW

 Experimental platform to test treatment

efficacies for water-vectored constituents

 Complimentary to full-scale ICW systems  Experimental investigation of ‘conventionally

difficult’ wastewater treatment

 Practical test bed for preliminary

experimental treatment

Meso-scale ICW

 Versatile

• Inherent concepts/design allow for the examination of a wide

range of wastewaters

 Affordable

• Using easily sourced materials and equipment keeps

construction and maintenance costs to a minimum

 Replicable

• Affordability allows for high-replication of parameters and

treatment methods

 Adjustable

• Use of simple mechanics allows for the systems to be high

adjustable upon initial setup

 Accurate

• High replicate count rules out erroneous results and errors that

can occur: delivering high confidence values

Swine wastewater treatment in Ireland

Primary method: Land spreading Other methods: Anaerobic digestion, Composting

Initial development of Meso-scale ICW

 Creation and operation of a low-cost, linearly

scaled ICW system dealing with anaerobically digested (AD) piggery liquid

 Examination of the treatment of AD liquid using an

Integrated Constructed Wetland approach

 Examine the reliability of such an approach and

potential future use of the meso-scale as a test-bed system for experimental examination of various wastewaters

Drivers

 Water Framework Directive

• Directive 2000/60/EC
• S.I. 327 of 2012

 Nitrates Directive

• Directive 91/676/EEC
• S.I. 610 of 2010

 Septic Tank Infrastructure

• EU decision and penalties (2012)

 Convention on Biodiversity

• RAMSAR

Constructed wetlands and Wastewater treatment

• World-wide application
• Environmentally beneficial
• Cost effective
• Amenities

vs.

Design

Design

High replication M ultiple inflows Easily controlled

Design

Design

Operations

Operation Ammonia-N Hydraulic loading Effluent recycling

Normal 100 mg NH4/l 37 m3/ha/d no Recycling 100 mg NH4/l 37 m3/ha/d Yes (100%) High nutrient loading 200 mg NH4/l 37 m3/ha/d no High flow rate 100 mg NH4/l 74 m3/ha/d no

Operational timeframe

 Construction

• June 2008 to September 2008

 Operation

• November 2008 to June 2010
• 18 months fully operational

Operational difficulties

 Siphon effects  Overloading  Extreme weather

Ammonia-Nitrogen NH3

 Ammonia NH3

• Primary basis for dilution of influent

0.01 0.10 1.00 10.00 100.00 1000.00 10/12/2008 10/01/2009 10/02/2009 10/03/2009 10/04/2009 10/05/2009 10/06/2009 10/07/2009 10/08/2009 10/09/2009 10/10/2009 10/11/2009 10/12/2009 10/01/2010 10/02/2010 10/03/2010 10/04/2010 10/05/2010 Ammonia-nitrogen (mg/l) Date Tank 1 Tank 2 Normal Recycling HNL HFR

High flow Low flow

Threshold: 0.5 mg/l

Hydraulic loading

 Initial loading @ 100 m3/ha/d  After 15 weeks reduced to 68 m3/ha/d  After 17 weeks, reduced to 37 m3/ha/d

20 40 60 80 100 120 0.01 0.1 1 10 100 1000 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 NH4 (mg/l) Sampling week

Ammonia (NH4)

Cell 1 Cell 4 Storage tank Influent loading

Molybdate reactive Phosphorus (MRP)

 MRP Effluent levels

• Phosphorus is a key parameter in eutrophication

0.001 0.01 0.1 1 10

10/12/2008 10/01/2009 10/02/2009 10/03/2009 10/04/2009 10/05/2009 10/06/2009 10/07/2009 10/08/2009 10/09/2009 10/10/2009 10/11/2009 10/12/2009 10/01/2010 10/02/2010 10/03/2010 10/04/2010 10/05/2010

Molybdate reactive phosphorus (mg/l) Date Tank 1 Tank 2 Normal Recycling HNL HFR

High flow Low flow Threshold: 1 mg/l

 Exceptional removal with reduced loading

rates

Normal Recycling HNL HFR Ammonia 99.7% 99.9% 99.8% 99.1% MRP 97.7% 96.0% 94.6% 89.1% Nitrite 95.2% 96.2% 98.4% 83.8% Nitrate 93.0% 92.2% 81.7% 75.7% TON 93.4% 93.1% 92.9% 77.4%

Variability in the systems

0.010 0.100 1.000 10.000 100.000 1000.000 1 6 11 16 21 26 31 36 41 46 51 56 61 66

Ammonia-N mg/l

Sample Week Replicate 1 Replicate 4 Replicate 3 Replicate 2

Variability in the systems

0.001 0.01 0.1 1 10 100 1000 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69

Ammonia-N mg/l

Sample Week Series4 Series3 Series2 Series1

Variability in the systems

0.010 0.100 1.000 10.000 100.000 1000.000 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69

Ammonia-N mg/l

Sample Week Replicate 4 Replicate 3 Replicate 2 Replicate 1

Variability in the systems

0.010 0.100 1.000 10.000 100.000 1000.000 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69

Ammonia-N mg/l

Sample Week Replicate 4 Replicate 3 Replicate 2 Replicate 1

Discussion

 Linearly-scaled meso-scale systems

functioned similarly to other full-scale ICW systems

 Exceptional nutrient removal rates  High replicate count shows reliability in

recorded results.

Potential applications

 Ongoing discussion for development of

sludge treatment from municipal WTP

 Mine wastewater treatment (heavy metal

content)

 Landfill leachate investigation  High ammonia content wastewaters

Conclusion



Meso-scale approach

• Reliable test-bed
• Flexible interim experimental scale
• Easily maintained
• Low cost

 Land and equipment

• Feasible to have high replicate count
• Analysis of data
• Result comparison



Loading rates

• Capable of dealing with higher nutrient loadings (>200 mg/l)
• High flow showed substantial mass removal, but effluent nutrient levels higher



Recycling

• Effluent recycling yielded consistently low effluent nutrient levels (ammonia-N)
• Year-round performance increase
• 4-fold effect; longer retention time, further dilution, extended treatment time, reduced

effluent volume