Presentation hesy 12-02-2014 Recirculation Aquaculture Systems
Recirculation Aquaculture
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Transcript of Recirculation Aquaculture
Recirculation Aquaculture
Why Recirculation• Water use
• Climate
• Quality
• Predation
• Environmental impact
• Land
• Disease
• Exotic species (or control thereof…
Cost of Labor : $7/day
Solids Siphon
Near Ensenada, Mexico; 2002
Near Ensenada, Mexico; 2002
Near Ensenada, Mexico; 2002
Raise a lot of fish with Little Labor
Recirculating System:
A production system that reconditions water to extend it’s reuse
A technique that increases the value of a limited resource
An artificial well that never ceases to flow
A stable platform forming a reliable base for commercial production
Definitions
• Five Major Processes1) Circulation2) Clarification (Solids capture)3) Biofiltration (BOD reduction/nitrification)4) Aeration (Oxygen replacement)5) Degasification (CO2 stripping) DENITRIFICATION
ION BALANCE
GAS STRIPPING
ALKALINITY ADDITION
DISSOLVED
REFRACTORY
MANAGEMENT
AERATION
SOLIDS REMOVAL
SOLIDS
TAN
BOD
SOLIDSB A C TE R IA
N
NO
CO
O
INERT
NO2
2
3
--
2
2
CO2
O2
FEED
BOD REDUCTION
NITRIFICATION
H+
Solids Capture
Circulation Aeration
Biofiltration
Fish Tank
The Five Major Processes in a Recirculating System
Feeding
Degasification
Five Major Treatment Objectives
Double Drain at Center of Tank
Return toTank
Sludge outlet
Inlet
Outlet
From Under-drain
Over-Drain Flow
Captured Solids
Microscreen Cleaning Jets
From Microscreen
Micro-Bead Filter
1 mm Styrene Beads
Centrifugal Pumps
Pressure line from CentrifugalPumps
02 Flow Meter
Pressure GaugeWater
OxygenBubbles
Return to Tanks
Solids Capture
Circulation Aeration
Biofiltration
Fish Tank
Feeding
Degasification
Solids Capture
Impact of Solids on Recirculating Systems
Impact of Solids on Recirculating Systems
• Increased BOD load (organic solids) causes problems with Biofilters
• Increased system turbidity (fine particles)
• Gill damage in fish (fine particles)
Solids Capture
Particle Size Distribution (microns)Particle Size Distribution (microns)
10-4 10-3 10-2 10-1 1 10 100
Dissolved Colloidal Suspended
Settleable
Solids Capture
No Fine Solids Capture
Tilapia
Foam Fractionation
Granular Filter
Microscreen
Tube Settler
Cartridge Filter
CoarseScreens
PlainSedimentation
100 75 30 10Particle Size, microns
SOLIDS REMOVAL PROCESSES AND PARTICLE SIZES
INFLOW
OUTFLOW
Inle
t Zon
e
Out
let Z
oneVs
Vh
Sludge Zone
Settling Zone
(Vs > Overflow Rate to settle)
SEDIMENTATION
Solids Capture
Solid Removal Technologies
• Effective for selected particle size
• Differ in headloss…energy $$$
• Differ in labor for upkeep
• Sensitive to organic loading
Solids Capture
Floor Plan
TANKS
Pump
Bead Filter
Fluidized Bed
Lime Addition
Liquid O2
Packed Column
Packed Column
““BYPASS” FILTRATIONBYPASS” FILTRATION
TANKS
Pump
Bead Filter
Fluidized Bed
Packed Column
Shrimp Maturation in South America
“IN-LINE” FILTRATION
Solids Capture
Circulation Aeration
Biofiltration
Fish Tank
Feeding
Degasification
Types of Biofilters
Biofiltration
PlasticBead
Heterotrophic Biofilm
Embedded NitrifyingBacteria
Oxygen
Organic Wastes
Carbon Dioxide
BOD
Decay
Nitrite
Oxygen
Carbon Dioxide
Bicarbonates
Nitrate
Nitrification
Ammonia
Biofiltration
TSS
BOD Bacteria
NH + NH
Nitrobacter sp.
Nitrosomonas sp.
NO
NO (Nitrate)
(Nitrite)
O
O
CO
CONitrification
(Total Ammonia)
TAN
HCO
HCO
3 4+
2
2
2
2
2
3
3
3
HeterotrophicBiofiltration
Inert M aterials
N itrifier rich
H eterotrop hs
B ound ary L ayer
B u lk W ater
M aterial S u rface
Inert M aterials
N itrifier rich
H eterotrop hs
B ound ary L ayer
B u lk W ater
M aterial S u rface
Biofiltration
0
100
200
300
400
500
TA
N C
onve
rsio
n (g
ms/
m3 -d
ay)
Beads Modified Beads Tubes
0.45 kg/m0.45 kg/m33
USDA - SBIR/AST, 97USDA - SBIR/AST, 97
Production Units
Propellor-washed Floating Bead Filters
Filtration Backwashing
Sludge
Return
Bypass
Pressure GaugeSludge View Port
Anti-siphon valve
Intake
Broodstock
ADM Tilapia System
Solids Capture
Circulation Aeration
Biofiltration
Fish Tank
Feeding
Degasification
Gas Exchange
Different Behavior
• Oxygen– 21% of air
– Saturation 10 mg/l
– Poorly soluble
– Transfer H20 limited
• Carbon Dioxide– 0.035% of air
– Saturation 0.5 mg/l
– Highly soluble
• 50 mg/l +
– Transfer gas limited
Oxygen goes in easier than CO2 comes out
Gas Exchange
Enrichment Devices
•Commonly used for large scale applications•Self-generates pressure (150-200 psi)•1 m3 liquid860 m3 gas•Dependent on local source of liquid oxygen•Not impacted by power failure •15-35cents/kg typical
Timmons and Lorsordo (1994) pg. 188Liquid Oxygen
Gas Exchange
No CO2
Removal
• Air stones
• Paddle wheels
• Surface Agitators
• Spray nozzles
• Packed columns
Gas Exchange
Ambient Air –Oxygen Addition and Carbon Dioxide removal are balanced
Gas Exchange
Ambient Air Options
Solids Capture
Circulation
Aeration
Biofiltration
Fish Tank
Feeding
Degasification
Circulation
Circulation Options
Airlift
Air
Air
Pump
Circulation
Air
Air
Airlifts Perform Several Functions– Circulation
– Aeration
– C02 stripping
– Foam control
B
D
E
(1)
(3)
(6)
A
Water
(2)
(7)
AirWater
Patent # 5,770,080
Water Flow
(4)C
(5)
Air Flow
Sludge
Water Flow
Air Bleed Builds Charge
Settled BackwashWaters returned to
system
Filter Mode Drop Filters : Low Water LossFloating Bead Bioclarifiers
E
(1)
(3)
(4)
(6)C
(2)
(7)
Water
(5)
Air
Patent # 5,770,080
Air Flow
Water Flow
Internal Sludge Capture
Drop Filters : Low Water LossFloating Bead Bioclarifiers
Released Air Washes Beads
Backwashmode
Fish Tank
Feeding
FAS 1012C: Recirculation Aquaculture Quiz Name:_________________List the five major treatment objectives and explain what they do.