The effects of wastewater and nitrogen source on accumulation of Chlorella based bioenergy

• Main Authors: Chi-Han Kao, 高啟瀚
• Other Authors: Yu-Tzu Huang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/bk832b

碩士 === 中原大學 === 生物環境工程研究所 === 103 === With great industrial developments in Taiwan, raw materials and plenty of compounds are used in the processes which result in more complex compositions of wastewater. In fact, excess nitrogen-containing compounds can cause water pollution, such as Eutrophication and algal blooms. Actually, our government had promulgated the standards of ammonium concentration in wastewater discharging to prevent our environment from damaging. In the other hand, compared to corn and palm trees, algae have more economical advantages such as faster growth, higher productivities, easier to be cultivated, and less planting area, etc. Furthermore, the compositions of algal lipids are similar to ordinary diesel fuel which can be used to produce biodiesel easily after extracted. Algae are not only economical plants with highly competitive, but capable to fix carbon dioxide during growth, which make algae a great potential to be the sources of recycling energy. In this study, we are going to observe the effects of algal productivities simulated by different nitrogen-concentration cultivations. Besides, we also focuses on the following subjects: (1) analysis optimal growth conditions for algae in different nitrogen-concentration mediums, and (2) explore the relationship between nitrogen consuming and oil accumulating, and compare the carbon chain structures between the algal lipids and fossil diesel. Here are our results: (1) Taiwan local algal strain P-A can be cultured in artificial synthetic wastewater which has the best growth conditions and the largest cell concentration. (2) Taiwan local algae P-A is capable to effectively remove BOD, NO2-, and NO3- which removal rate are up to 85.64%. Besides, the removal rates of TP, TN, TKN are reached above 70.91% during wastewater treatment. (3) Two-step wastewater culture with different medium has the best lipid concentration at 18th hours up to 53.72%, yield 108.17 mg L-1d-1. (4) The results suggest the best growth condition of algae is 407.56 mg/L carbon (glucose) and 634.70 mg/L nitrogen (NO3-) and nitrogen concentration shows more critical than carbon during the cultivating.