碩士 / 中華大學 / 土木工程學系碩士班 / 102 / In today's environment, energy depletion has increasingly become a serious problem. All the countries in the world are, thus, looking for highly effective alternative energy sources. A wide range algae are denoted with its many features. Parts of them can be cultured to produce biomass energy, such as biodiesel with the quality better than one made from the general feed stocks, becoming the key source of supply for today's raw energy demand.
This study chose Nannochloropsis oculata as a major algae, because it's high content of fat in cells, of which we can effectively extract for high quality of oil. The purpose of this study was to use NaHCO3 as a main carbon source to replace the traditional use of 2% CO2 gas mixture, in order to achieve a cost-effective culturing in a large-scale algae bioenergy plant. The results show that the addition of 7.6 g/L NaHCO3 obtains the best algal productivity and yield of about 4 g/L and 0.52 (g/L/day). After seven-day culture under the same conditions, the use of added NaHCO3 has about 0.18 g/L of microalgae cell content and 0.03 (g/L/day) of yield in difference as compared to the traditional addition of 2% CO2 gas mixture, indicating that the cheap and easy handling NaHCO3 can be used as an alternative carbon source for replacement of CO2 gas mixture for cultivation of microalgae and maintain the culture of effectiveness. The cost of using NaHCO3 was proved to be only one-fiftieth of using 2% CO2 gas mixture.
In follow-up studies, the improved thin flatbed photo-bioreactor, designed to reduce the distance of the light pass, can solve the traditional drawback in the limit of the effective conduction of light when cultured concentration increased, thereby inhibiting the growth of algae shortcomings. In use of NaHCO3 as an inorganic carbon source with light intensity of 15000 Lux and culture medium circulation rate of 8 L/min, the results of experiment show that the maximum cell density of 4.42 g/L and the average yield of microalgae of 0.96 (g/L/day) were achieved in the three days of incubation in the semi-continuous test, displaying about double effectiveness to that from the traditional photo-bioreactor. Consequently, this proposed system not only can effectively reduce the economic costs but also increase the microalgae cell density and production rate. It can effectively help to capitalize on future large-scale cultivation for production of biomass energy, and applied to remove the excess of carbon dioxide.
| Identifer | oai:union.ndltd.org:TW/102CHPI5015036 |
| Date | January 2014 |
| Creators | Kuan-Yu Lin, 林冠佑 |
| Contributors | Sz-Chwun Hwang, 黃思蓴 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 68 |
Page generated in 0.0015 seconds