Optimal culture conditions of oil production by microalgae Chlorella sp.

• Main Authors: Ye, Hsiu-Feng, 葉修鋒
• Other Authors: Hwang, Shyh-Jye
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/70755338672915333973

碩士 === 國立清華大學 === 化學工程學系 === 97 === Due to human activities and industrialization development consumption massive fossil fuels, resulting in the environment questions and so on greenhouse gas accumulation as well as crude oil supply drop, in which carbon dioxide is the main greenhouse gas for causing the phenomenon of global warming. Therefore, it is necessary to development a substitute energy source for petroleum which is renewable, carbon neutral and be able to reduce atmospheric carbon dioxide concentration. Microalgae are photosynthetic autotrophs, which can efficiently utilize carbon dioxide as carbon source and convert it to lipid through photosynthesis. Many species of microalgae have the ability to produce large number of triacylglycerols and fatty acids in the adverse environmental conditions. Thus it can be seen, microalgae are not only for carbon dioxide fixation, but also can produce a large number of oils as a source of raw materials for biodiesel. Chlorella sp. is oleaginous microalgae, literatures indicate that the average oil content is 20-50 % dry cell weight, therefore Chlorella sp. is excellent raw material for biodiesel production. In order to obtain a higher oil yield, the effects of environment conditions and nutrient factors on Chlorella sp. growth and oil production was investigated. In this study, we will confirm the optimal culture conditions to obtain higher biomass and oil productivity. The results show that Chlorella sp. grown on optimal culture conditions (pH 8, salinity: 8.5 g/L, air flow rate: 2 L/min, L/D: 12/12, temperature: 30 ℃, light intensity: 12000 lux, CO2: 5 % and 0.1 g/L urea) after 14 days, it could obtain maximum biomass (2.85 g/L) and oil productivity (48.2 mg/L．day).