- 期刊
小球（Chlorella vulgaris）於模擬煙道氣環境下之最適生長條件探討
Optimal Growth Conditions of ＂Chlorella vulgaris＂ in a Simulated Flue Gas Environment
摘要
微藻對於CO_2吸收有良好的轉換效率，但若讓小球藻在類似煙道氣的環境下（含高濃度CO_2和SO_x）是否仍可以存活？最適生長條件又為何？本研究將模擬在煙道氣的各種操作條件下，小球藻的培養試驗，了解小球藻可以忍受和最適生長條件範圍。本研究主要試驗項目為：CO_2濃度、pH、溫度、光照比例，及不同pH值下之Na_2SO_3濃度變化試驗，分成批次和連續曝氣培養。早晚曝氣培養下，當CO_2濃度為15%，小球藻有最佳平均生長速率，為25.5mg/L/day；早晚曝氣兩次的小球藻可以忍受到35%的CO_2，pH6、25℃為小球藻最適合生長環境；高於或低於此pH及溫度生長量與速率會逐漸減少，pH4和9，生長溫度於15和35℃開始受到抑制。小球藻全天日照有最大產量和平均速率均為最佳，但就單位時間照光之小球藻產率（mg/L/day）照光時間）以12小時照光，有最高產率，也最符合經濟價值。當pH6時小球藻可以忍受50 mmol Na_2SO_3，pH 5時可以忍受20mmol Na_2SO_3，pH4時只能忍受10mmol Na_2SO_3。小球藻之連續曝氣培養，最適pH、溫度、光照比例結果都與批次相同，可以忍受到30%的CO_2，較早晚兩次曝氣低；生長速率以CO_2為15%時，小球藻有最佳平均生長速率，為31.4mg/L/day。當pH6時小球藻可以忍受40mmol Na_2SO_3，其忍受度稍低於早晚兩次曝氣試驗。小球藻操作條件迴歸式：x=0.98^(∣24- a∣)(5.88* S /(91.3+S+S^2/7.16)×c^(∣pH-6∣)×d^(∣T-25∣)
並列摘要
Microalgae demonstrate effective conversion efficiency in absorption CO_2. However, it is difficult to determine whether ＂Chlorella vulgaris＂ can survive in a flue gas environment filled with high concentrations of CO_2 and SO_x. In this study, ＂Chlorella vulgaris＂ were cultivated under various simulated operating conditions in a flue gas environment to determine a tolerable range and the optimal conditions for its growth. The main test items used in this study were CO_2 concentration, pH, temperature, illumination proportion, and Na_2SO_3 concentration varied according to different pH values to simulate the conditions of flue gas. The tests were mainly divided into batch-type aeration and continuous aeration cultivation. During morning and evening batch aeration cultivation, a 15% CO_2 concentration resulted in the highest growth rate of 25.5 mg/L/d. The ＂Chlorella vulgaris＂ that experienced morning and evening batch aeration could endure an environment of up to 35% CO_2, with pH 6 and a temperature of 25 ℃; these were the most suitable environments for the growth of ＂Chlorella vulgaris＂. The growth rate of ＂Chlorella vulgaris＂ at a higher or lower pH and temperature was gradually decreased, and was inhibited when it reached pH 4, 9 and 15, 35℃. Full-day illuminated cultivation led to the most production and highest production rate of ＂Chlorella vulgaris＂. However, regarding the production rate per unit time of illumination (mg/L/day/illumination time), the test with an illumination ratio of 1:1 demonstrated the highest and most economic test. At pH 6, ＂Chlorella vulgaris＂ could withstand 50 mM of Na_2SO_3. At pH 5, it could withstand 20 mM of Na_2SO_3, and at pH 4, it could withstand only 10 mM of Na_2SO_3. The continuous aeration cultivation of ＂Chlorella vulgaris＂ showed identical results for pH, temperature, and an illumination ratio to the batch aeration cultivation, however it could withstand a CO_2 concentration of only 30%, which was lower than that of the cultivation with morning and evening batch aeration cultivation. The highest growth rate of ＂Chlorella vulgaris＂ was 31.4mg/L/d, with a CO_2 concentration of 15%. In a pH 6 environment, it could withstand 40 mM of Na_2SO_3, which was lower than the cultivation test with morning and evening batch aeration cultivation. Operation conditions regression of ＂Chlorella vulgaris＂: X=0.98^(∣24- a∣)(5.88* S/(91.3+S+S^2/7.16) g)×c^(∣pH-6∣)×d^(∣T-25∣)