Post on 27-Feb-2022
transcript
Solid-liquid separation of effluent produced by a fixed media biofilm reactor
Bernard Patry, Étienne Boutet, Serge Baillargeon and Paul Lessard
10th International Conference on Biofilm Reactors,
9th – 12th May 2017, University College Dublin, Ireland
Outline
• Context
• Objectives
• Methodology
• Experimental results
• Conclusions
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Context
Why treat suspended solids (SS) ?
O2 limitationEutrophicationToxicity
Discharge standards: 25 g/m³ in Canada
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= f(detached solids properties)
Context
• Solid-liquid separation = limiting step in biological treatment processes
• Attached growth
= f(operating conditions)
Media
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Context
• Most available data Moving bed biofilm reactors (MBBR) and non-submerged media systems
Conditions Properties Performances
• Hydrodynamics
• Temperature
• Surface loading
rate and HRT
• Biofilm properties
• Detachment
processes
• Particles size
• Flocs morphology
• Effluent settled
and non-settled SS
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Outline
• Context
• Objectives
• Methodology
• Experimental results
• Conclusions
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Objectives
Pilot study to :
• Characterize settleability of solids from submerged fixed media
biofilm reactors
• Measure influence of surface organic loading rate (OLR) and temperature
• Explain performance variations
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Outline
• Context
• Objectives
• Methodology
• Experimental results
• Conclusions
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Methodology
Experimental site :
Grandes-Piles,
Québec, Canada
(415 inhabitants)
Québec city
(Université Laval)
MontréalOttawa
Saint-Laurent river
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Methodology
• Measured variables :
• Settleable solids: Standard Methods protocol
• Particle size distributions (PSD): Focused beam reflectance measurement (FBRM)
• Particle settling velocity distributions (PSVD): ViCAs (Vitesse de chute en
assainissement)
• Microscopic observations
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Outline
• Context
• Objectives
• Methodology
• Experimental results
• Conclusions
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Experimental results
Operating temperature influence
Mixed regression with repeated measurements:P-value < 0.01
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Experimental results
Operating temperature influence
Compositional data analysis:P-value < 0.01
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Experimental results
Relation between particles size and non-settleable solids
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Experimental results
OLR influence
>5 g soluble CBOD5/m2·d
SS concentration < 20 g/m³
Mixed regression with repeated measurements:P-value > 0.05
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Outline
• Context
• Objectives
• Methodology
• Experimental results
• Conclusions
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OLR
Conclusions
T°
Operating
conditions
Particles
properties
Size
Morph.Settling
potential
Settleable
solids
Settling
velocity
• Intermediate T° highest settling potential
• High OLR ≈ potentially increased settling potential
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