Table 3
Different methods employed for pretreatment of microalgae
Strain
Processing
conditions
Method of
pretreatment
Operating conditions
Biogas production
Reference
Before
pretreatment
After
pretreatment
Nannochloropsis
salina
40 days (38 °C)
Freezing
overnight
−15 °C, overnight
0.347 L
biogas/g VS
0.233 L
biogas/g VS
Schwede et al.
(2011)
Thermal
100 °C, 8 h
0.549 L
biogas/g VS
Microwave
5
 until boiling at 600 W,
2450 MHz
0.487 L
biogas/g VS
Ultrasound
3
 45 s at 200 W, 30 kHz
0.274 L
biogas/g VS
French Press
2
 10 MPa
0.460 L
biogas/g VS
Spirulina maxima
60 days (35 °C)
Ultrasound
10 min (polytron
generator)
0.19 L CH
4 /
g VS
0.17 L CH
4 /
g VS
Samson and Leduy
(1983)
Thermo-chemical
50 °C (1 h in water bath)
0.21 L CH
4 /
g VS
100 °C (1 h water bath)
0.22 L CH
4 /
g VS
150 °C (1 h in steam
sterilizer)
0.24 L CH
4 /
g VS
Scenedesmus
sp.
34 days (35 °C)
Thermal
70 °C, 25 min
0.082 L
CH
4 /g COD
0.089 L
CH
4 /g COD
González-Fernández
et al. (2012b)
80 °C, 25 min
0.129 L
CH
4 /g COD
Ultrasound
130 MJ/kg, 30 min
0.154 L
CH
4 /g COD
(continued)
4 Process Intensification of Biofuel Production …
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