Effects of drying and storage on year‐round production of butanol and biodiesel from algal carbohydrates and lipids using algae from water remediation

Abstract

Algae harvested from a pilot water quality improvement technology at the Rockaway Wastewater Treatment Facility in New York were examined as a source of carbohydrates and lipids for the production of biofuels. Dried stocks of algae harvested during a 6‐month period were used to feed the bioreactors, and the process to extract sugar from the natural wastewater grown algae was optimized. The length of storage time, storage conditions, sugar extraction process, and fuel production were studied. The results show that if the algae is stored dry (<25% moisture) the algae stock can be used for up to a year with good conversion of carbohydrates to sugars using a 10% w/v of dried algae. These optimized conditions extracted the maximum amount of sugar, which yielded an average of 0.11 (g butanol/g sugar) from the bioreactors year‐round from a wide range of diatoms and other microalgae used to treat wastewater. Similarly, lipids could be obtained from the stored algal with value of >0.015 g/g algae even after a year in storage. These results demonstrate the potential for year round production of fuel from algae harvested as part of a water reclamation process. © 2013 American Institute of Chemical Engineers Environ Prog, 32: 1013–1022, 2013

Enhanced bioenergy recovery from oil‐extracted microalgae residues via two‐step H2/CH4 or H2/butanol anaerobic fermentation

“…The highest butanol yield of 0.086 g/g‐carbohydrate was lower than the yield of 0.13 g/g‐carbohydrate presented in literature , indicating that the optimal concentration of OMR for butanol production required further investigation. Theoretically, two moles of NADH are generated from one mole of glucose via glycolysis, while it requires two moles of NADH for converting of acetyl‐CoA to butyrate and another two moles of NADH for further butanol production .…”

Biological butanol production from microalgae-based biodiesel residues by Clostridium acetobutylicum

“…using different organic wastes including algae biomass has been reported, as summarized in Table 4. Jernigan et al (2013) used algae as substrate and reported a butanol yield of 0.13, which was approximately two-third of control batch presented in Table 3, presumably due to incomplete consumption of carbohydrate in algae residues . Higher butanol production from algae biomass has been reported in Nakas et al (1983) and Ellis et al (2012) by adding inducers.…”

Production of recombinant protein in Escherichia coli cultured in extract from waste product alga, Ulva lactuca

“…Seasonable variability of U. latuca has been recently examined based on total carbohydrate and not patterns of individual sugar production. 24 In this study, the total carbohydrate varied between 42 and 46% of dry cell weight, indicating that the total carbohydrate mixture does not drastically change. Therefore, U. latuca hydrosylate would likely be used to produce industrial enzymes such as lipases or cellulases, rather than a therapeutic.…”

“…Lack of a diauxic response (Figures and ) indicated that the major carbohydrates are being consumed in a nonpreferential manner, eventually providing for GFP expression. Seasonable variability of U. latuca has been recently examined based on total carbohydrate and not patterns of individual sugar production . In this study, the total carbohydrate varied between 42 and 46% of dry cell weight, indicating that the total carbohydrate mixture does not drastically change.…”