The absorption of CO
2 and O
2 gas into the chlorella suspension and the stripping of O
2 gas generated by photosynthesis of chlorella through the hydrophobic microporous hollow fiber membrane of polypropylene took place. The chlorella suspension flowed inside the hollow fibers and the gas mixture of CO
2 and air flowed outside them. The following results were obtaind: (1) Overall mass transfer coefficient of CO
2 and O
2 gas for absorption depended only on the flow rate of suspension in the fibers, and was correlated by the dimensionless equation given below.
Sh=
A(
Pe)
1/3. (2) The photosynthetic reaction rate did not depend on the CO
2 concentration in the suspension in the range of 1.5 to 5.0mol·m
-3. (3) The supply of CO
2 gas and the stripping of O
2 gas generated by photosynthesis could be carried out with the same membrane module. (4) The membrane area required to get the maximum generation rate of O
2 gas can be estimated when overall mass transfer coefficient, chlorella concentration and CO
2 concentration in feed gas mixture were given.
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