การเพิ่มผลผลิตบิวทานอลจากสาหร่ายขนาดเล็กด้วยการบูรณาการการหมักแบบไร้แสงร่วมกับการหมักที่มีระบบเก็บเกี่ยวบิวทานอล

Abstract

Production of volatile acid in CSTR at 5 L working volume from microalgae (Chlorella sp.) fermentation of HRT 6 day showed a hydrogen yield of 161-189 mL-H2/g-VSadd and production rate 1,938-2,269 mL-H2/Lreactor with the production of acetic acid propionic acid and butyric acid produced during the experiment were in the range of 5.25±0.14 g/L, 0.76±0.02 g/L and 7.50±0.15 g/L, respectively. The main bacterial in the fermentation of mixed culture were Dysgonomonas mossii, Porphyromonadaceae bacterium, Proteiniphilum saccharofermentans, Lysinibacillus macroides, Clostridium sp. strainS6, Ruminococcaceae bacterium, Acetobacter pasteurianusและ Comamonas aquatica. Higher butanol concentration of 10.17 g/L was produced from Clostridium beijerinckii ATCC10132 at 40 g-VS/L initial glucose concentrations than 20 60 and 80 gVS/L. The initial concentration 40 g-VS/L of microalgae pretreatment with 108 °C autoclave for 30 min with nutrient addition was produced butanol 2.30 g/L which higher than untreated. In addition, by studying the B/G ratio from the Taguchi experimental design, the results showed that batches with acid concentrations from 2-10 g/L had better yields compared to those with acid concentrations up to 14 g/L. From the experiment, it was found that the combination of 10 g/L butyric acid with 20 g/L glucose yielded the highest butanol yield at 3.67 g/L from the 15% inoculation concentration. Butanol production yield from CSTR with semi-continuously fed 20 gVS/L glucose on TYA medium at HRT 2 day was constant in the range of 5.51 g/L, 38% hydrogen concentration with yield of 74 mL-H2/g-VS ( 740 mL-H2/L/d). When Stripping gas (CO2 and 30%H2 ) 3 L/min, blowing in the fermentation system for 48 hours continuously, it was found that the harvest butanol was 43.86% with 75.29% Efficiency of condensation, with 10.84 percent loss. During the first gas stripping from the fermented of 5.51 g/L butanol concentration, in the first 4 hours, the highest butanol concentration was obtained in the first condensing unit at 45.17g/L. This stripping process is suitable if the fermentation process was high solvent yield. In addition, the test results to produce butanol from the effluent of rich butyric acid together with 20 g-VS/L Glucose, it was found that in the early period it was produced butanol 5.54 g/L with hydrogen production 117.68 mL-H2/g-VS. The acid content is increased in the system and affects the growth and activity of Clostridium beijerinckii. A reduction in the acidic substrate concentration is necessary since the acid in the fermentation solution is not only butyric acid but also contains other types of volatile acids