Investigation of photobioreactor design for enhancing the photosynthetic productivity of microalgae

As photosynthetic efficiencies are relatively high at irradiation levels of <500 mu mol m(-2) s(-1), photosynthetic productivity could be increased by redistributing strong light over a larger photo-receiving area using conic al, helical, tubular photobioreactors (HTP). When Chlorella were exposed to light irradiation of 980 mu mol m(-2) s(-1), the ratio of productivities w as 1.00:1.13:1.23:1.66 for conical HTPs with cone angles of 180 degrees (fl at type), 120 degrees, 90 degrees, and 60 degrees, respectively. This sugge sts that photo-redistribution technology is a highly effective and convenie nt approach for increasing the photosynthetic productivity of microalgae. ( C) 2000 John Wiley & Sons, Inc.