Study on Medium Composition of Microalgae Optimization for CO{sub}2 Removal From Air by A Membrane-Photobioreactor

摘要

In this paper, a 3 L membrane-photobioreactor was first prepared to study the CO{sub}2 removal capability using Chlorella pyrenoidosa. The CO{sub}2 was efficiently removed from the airstream when the following operating conditions were set: the inlet airflow of 0.6 L/min, the aeration gas containing 1% CO{sub}2, light intensity of 3500 Lx, at 25～30 and pH at 8.5～9.5. It showed that CO{sub}2 concentration in the discharged gas decreased 50% compared to that in the aeration gas, and the removal capacity of the experimental photobioreactor was 0.118 g CO{sub}2/(L-medium h). The medium composition of C. pyrenoidosa for CO{sub}2 removal from air was also studied in a 10 L enclosed photobioreactor, in which the proper values of temperature, pH and dissolved oxygen (DO) were controlled on-line. In order to alleviate the influence of DO on the growth of microalgae, N{sub}2 was also used to form mixed aeration gas instead of condensed air. Based on the ascertainment of the mode of inorganic carbon (Ci) uptake, the concentration changes of (HCO{sub}3){sup}-, (CO{sub}3){sup}(2-), (NH{sub}4){sup}+, (PO{sub}4){sup}(3-), (NO{sub}2){sup}- and (NO{sub}3){sup}- were analyzed during the process of high-density photoautotrophic microalgal culture. Consequently, the optimization performance of CO{sub}2 removal by the high-density photoautotrophic microalgal culture will be carried out in this lab under optimum operating conditions.