Kania Dewi

Preliminary Study on Climate Change Biomitigation by Improving CO2 Removal and CO2 Utilization Efficiency Using Microalgae Culture in Photobioreactor

Culture conditions are very important to CO2 bio-fixation related with the CO2 removal efficiency through biological process by microalgae photosynthesis activities. The aim of the research was to study how high CO2 utilization efficiency could reach in mix culture that supplied high CO2 concentration (2%, 5%, and 7%) continuously from the bottom of photobioreactor. The mix microalgae culture containing of Chlorella sp, Scenedesmusobliquus and Ankistrodemus sp. were cultivated in photobioreactor with various environmental treatments i.e light intensities, light periodism and temperatures whereas the fixed CO2 gas flow rate of 8 L.min-1. The results showed that microalgae growth was best at light intensity of 4000 lux for 16/8 hours light/darkness cycling, 30°C and 5% CO2 supplied, indicated by the highest dried biomass (g.L-1), the highest Carbon content was g.d-1 and highest CO2 removal efficiency (%) that were 2.7, 11.9, 49, respectively. However the highest CO2 utilization efficiency for bio-fixation phenomenon was obtained from culture that supplied by 2% CO2 concentration, the value was almost 2 fold than 5% CO2 supplied and 4 fold than 7% CO2 concentration supplied, respectively. Biological fixation of CO2 are greatly affected by the characteristics of the microalgae strains and their tolerance to environmental conditions.