Task 3
By: Erdenesuvd Bat-Erdene
Overall Process of 5 tons/year
Astaxanthin production plant
M1.2 AIR
M1.3
M1.1 CO2
Medium
M3.2 AIR
M2.2 AIR
M2.3
M2.1 CO2 Medium
M2.4
Waste Gas
M1.4
Waste Gas
E-1
25,000L
PBR
M2 Cell
Culture
M1 INOCULUM
M4.2
M4.1 CO2 Medium
M3.4
M4.3
Waste Gas
Waste Gas
E-3
E-2
6000L PBR
M3.3
Medium
M3.1 CO2
3d PBR
M3 Cell
Culture
M2.5
Supernatant
E-2
E-5
E-4
Pond
M4 Cell
Culture
M3.5
Supernatant
E-3
M5 Cell
Slurry
M4.4
Supernatant
E-4
Sedimentation
Tank
M5.1 Supernatant
M10.2
Astaxanthin
M7.1 Evaporated
Waste Water
M7.2 Waste Air
E-6
Centrifuge
M6
Sedimented
Slurry
E-8
E-7
Spray Dryer
M7
Algae
Paste
M9
M8
Dried
Algae
Pulveriser
E-9
Extraction
M10
E-10
Purification
M7.3 Hot Air
M6.1 Supernatant
M7.4 Biomass
Waste
M8.1 Biomass
Waste
M9.1 Biomass
Waste
M10.1 Biomass
Waste
Mass Balance of Dry
Biomass
•
•
Biomass concentrations in Inflow and Outflow Basis:
Based on residence time 5 days and daily 6 hours of solar illumination in Kunming,
China (Ref 1).
Start Cell biomass
End cell biomass
6 x 10^7cells/L
5 x 10^8 cells/L
•
Method: biomass dry weight 0.0004 kg/L in the final pond culture
•
In the ponds the cell culture is harvested but not grown. So the cell concentration
in the pond will be 6x10^7cells/L
Per cell biomass: = 0.0004/(6x10^7) = 6.67x10^-12 kg/cell, confirms with the
1x10^-12kg/cell from Ref 2.
•
•
•
Biomass IN (kg/day) = Start cell biomass (cells/L) x per cell biomass (kg/cell) x
Volumetric flowrate (L/day)
Biomass OUT (kg/day) = End cell biomass x per cell biomass x Volumetric Flow rate
Mass Balance
• Nutrient medium: 10 mM KNO3, 2 mM
Na2HPO4, 0.5 mM CaCl2, 0.5 mM MgSO4, 2 mM
NaHCO3 (Ref 1)
• Air: Aeration rate 0.05 vvm (Ref 1)
• Mass concentrations of components in Air: 23.2%
O2, 75.5% N2, 1.3% Ar. Assuming Oxygen is used
fully, N2 and Ar are inert. Oxygen concentration
150% saturation is desired. (Ref 2).
• CO2 in: 15vol% going into 6000L and 25,000L
PBRs (Ref 1)
• CO2 out: 75mass% going out from PBRs (Ref 3).
M1.2 AIR
Oxygen
Nitrogen
Argon
73.63 kg
239.61 kg
4.13 kg
MASS BALANCES kg/day
KNO3
3.49 kg
Na2HPO4
0.98 kg
CaCl2
0.19 kg
MgSO4
0.21 kg
NaHCO3
0.58 kg
Water
2960.90 kg
CO2
Nitrogen
Argon
M1.3
Medium
M1.1 CO2
3.89 kg
239.61 kg
4.13 kg
M1.4
Waste Gas
CO2 5.18 kg
E-1
6000L PBR
M1 INOCULUM
1.38 kg
0.42 kg
0.12 kg
0.023 kg
0.025 kg
0.070 kg
412.68 kg
Total mass going In = 3703.62 kg/day
Total mass going Out = 3703.62 kg/day
Residence time 5 days
Dry Biomass
Water
11.53 kg
3444.47 kg
Biomass Growth
600000000
500000000
Biomass cells/ L
Dry Biomass
KNO3
Na2HPO4
CaCl2
MgSO4
NaHCO3
Water
M2 Cell Culture
y = 9E+07x + 6E+07
400000000
300000000
200000000
100000000
0
0
1
2
3
4
Days
5
6
7
MASS BALANCES kg/day
M2.2 AIR
Oxygen
Nitrogen
Argon
153.39 kg
499.18 kg
8.60 kg
KNO3
Na2HPO4
CaCl2
MgSO4
NaHCO3
Water
29.12 kg
8.18 kg
1.60 kg
1.73 kg
4.84 kg
25134.34 kg
M2.3
Medium
M2.1 CO2
CO2
CO2
Nitrogen
Argon
32.40 kg
499.18 kg
8.60 kg
M2.4
Waste Gas
43.2 kg
E-2
25,000L
PBR
M2 Cell Culture
Dry Biomass
11.53 kg
Water
3444.47 kg
M3 Cell Culture
Dry Biomass
Water
Total mass going In = 29340.18 kg/day
Total mass going Out = 29340.18 kg/day
Residence time: 5 days
96.05 kg
28703.95 kg
ENERGY BALANCES
Energy Balance for 6000L PBRs (Assume Turbulence power and solar
radiation negligible at this stage)
Cooling Duty = Energy In – Out + Turbulence Power + Solar Radiation
m (Kg/Day)
Cp (KJ/Kg/C)
Inlet Temperature
Outlet Temperature
∆T
Q (KJ/day)
Q(KW)
Air Supply
Medium and
CO2 Supply Cell culture
(O2,N2,Ar)
Water
317.37
5.18
414.72
2966.35
1.005
0.8439
4.184
4.184
25C
25C
20C
25C
20C
20C
20C
20C
5
5
0
5
1594.78
21.86
0
62056.04
0.0185
0.000025
0
0.718
Total
0.737 kW
ENERGY BALANCES
• Energy Balance for 25,000L PBRs:
• Cooling Duty = Energy In – Out + Turbulence Power + Solar Radiation
m (Kg/Day)
Cp (KJ/Kg/C)
Inlet Temperature
Outlet Temperature
∆T
Q (KJ/day)
Q(KW)
Air Supply
Medium and
CO2 Supply Cell culture
(O2,N2,Ar)
Water
661.17
43.2
3456
25179.87
1.005
0.8439
4.184
4.184
25C
25C
20C
25C
20C
20C
20C
20C
5
5
0
5
3322.38
182.28
0
526762.88
0.0385
0.00211
0
6.0968
Total
6.137 kW
Summary of Operational Parameters
Photo bioreactor process control parameters
Bioreactor culture temperature
Bioreactor aeration rate
pH
Starting cell concentration of PBRs
Final cell concentration for PBRs
Photo bioreactor process performance parameters
Power consumption for cooling a 6000L PBR
Power consumption for cooling a 25000L PBR
Power consumption for turbulence a 6000L PBR
Power consumption for turbulence a 25000L PBR
Aeration power input for the 6000L bioreactors
Aeration power input for the 25000L bioreactors
Days for 6000L bioreactor cell culture to be ready
Days for 25000L bioreactor cell culture to be ready
Values
Below 25 C
0.05v/v/m
6.5-7
6 x 10^7 cells/l
5 x 10^8 cells/l
Estimated values
60 kWh
160 kWh
15 kW
67.5 kW
0.6 kWh
2.5 kWh
5 days
5 days
Ranges
10-25 C
5-8 x 10^7 cells/l
5-7 x 10^8 cells/l
Ranges
0-120 kWh
0-320 kWh
4-6 days
4-6 days
Equipment Volumes
6000L PBRs
5days = V / (3703.62 kg/day)
V = 18518.1 kg
3 x 6000L PBRs needed
Mechanical Design for:
25,000L PBRs
5days = V / (29340.18 kg/day)
V = 146700.9 kg/ (1000kg/m3) = 146.70 m3
6 x 25,000L PBR needed
Choice of photobioreactor
Mechanical design of 25,000L PBR
• If one desires to provide large quantities of
cheap/free light to the cultures, the cultures
need to be taken outside.
• To be free from contamination they should be
enclosed.
• Each 25,000L PBR module has 100m2 land
surface area exposed to the sun
• Disadvantage: Large area needed
(6x25000LPBRs need area of 780m2)
Mechanical design of 25,000L PBR
• 4 parallel plastic tubes each 0.41 m diameter
34.5 m length laid on an impermeable surface
(Ref 2).
• Turbulence: air lift pump, Re ~ 4000
• Air lift pump Duty: 2–3.4 kW m-3
• Cooler: To control temperature 15 to 25C. PBR
is automatically flooded with cold sea water
from Kunming sea 600m under ocean surface.
• Cooler duty: 160 kWh
2D Model of 25,000L PBR
D= 0.41m
L= 34.5m
W = 3.89 m
X6
In real life…
3D Model of 25,000L PBR
Specifications of Ancillary
Items for 25,000L PBR
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Pumps
Air lift pump for cell culture going into PBRs
Centrifugal pump for outlet to the next PBR
Cascade Pumping System for cool water pump from deep ocean under
600m deep to the cooling pool.
Air Compressor Duty: 1.25kW x 6
Filters
Air and CO2 filters: 0.2micrometre membrane filter
Medium filters:2micrometre membrane filter
Pipes and tubes: 0.41 m diameter 34.5 m length PVC Plastic Pipes, narrow
PVC tubes used for sparging CO2 and Air to PBRs
Line sizes for in and outflow of cell culture and medium: Nominal Size 2.5,
OD 73 mm, Sch 40
Valves: Diaphragm valve for air, CO2 and water (fail-closed)
– Gate valve for cell culture
Tanks
CO2 Tank: Compressed tank stainless steel
Medium Tank: Stainless steel Tank
Control System Specification
• An outline of the intended control system:
• Computer controlled parameters:
• Nutrient concentration, Dilution rate,
Temperature, pH, Turbulence, Growth rate
• Cell count system: Model Z1 Coulter Counter
Ref 2.
P&ID
P&ID
Start Up procedure of 25,000L PBR
1.
2.
3.
4.
Make sure all valves closed V-9, V-8, V-13, and V-10
Medium Supply valve is opened, V-10
The plastic tubes were filled with medium
Medium discharge V-11, V-12 is opened and medium pump E-4
started
5. Medium drained to Supernatant storage
6. Close V-10 Medium supply
7. Close Drain valve V-12
8. Deep sea water V17 and V-18 opened and Pump E-6 was started
9. Switch isolators: cell culture V-6, V-8 and E-3, CO2 supply V-1 and
V-9, medium supply V-10, Air supply V-4, V-16 valves were
opened
10. Conditions of supplies are fully computer controlled
11. After the tube volume is filled, all incoming valves V-8, V-9, V-10,
V-13 etc. are closed
12. After 5 days V-13, V-14 opened and pump E-5 started to transfer
to the next PBRs
Shutdown Procedure
1. All incoming valves and pumps to PBR is
closed.
2. H2O cooler and all isolators switched off
3. Close V-13, pump E-5, V-14 valve
4. Open drainage valve fully V-12
5. PBR system was emptied of medium to
supernatant waste storage
References
• Ref 1: Jian Li, Daling Zhu (2011) An Economic
assessment of astaxanthin production by large scale
cultivation of HP
• Ref 2: Miguel Olaizola (2000) Commercial production
of astaxanthin from HP using 25,000L outdoor PBR
• Ref 3: Shu KI Tsang (2004) Optimal Harvesting strategy
for HP using stella based model
• Ref 4: http://www.tatupjournal.de/downloads/2012/tatup121_noua12a.pdf
• Ref 5: PBRs design and performance with respect to
light and energy input Otto, Pulz (1998)
Thank you for you attention
• Any questions?