Optimization of the digestion process of Scenedesmus sp. and Opuntia maxima for biogas production

Abstract Scenedesmus biomass is not an adequate substrate for anaerobic digestion due to its low biodegradability and low biogas yield. This study aims to evaluate the anaerobic co-digestion of Scenedesmus microalgal biomass and Opuntia maxima cladodes, the latter added in order to improve the digestion process. Batch assays were conducted to evaluate possible synergistic effects in different mixtures of both substrates. Mixture with highest methane yield was digested in semi-continuous mode at different VS concentrations. Feedstock composed of 75% O. maxima and 25% Scenedesmus (VS basis) showed the highest methane yield increasing 66.4% and 63.9% that of Scenedesmus and O. maxima, respectively. In semi-continuous mode, ideal organic loading rate (OLR) with 6%VS feed concentration was 4 gVS L−1 d−1, which yielded 292 ± 39 LCH4 kgVS−1 (15 days HRT). In the case of 8%VS feed concentration ideal OLR was 5.33 gVS L−1 d−1, which yielded 308 ± 22 LCH4 kgVS−1 (15 days HRT). The co-digestion of O. maxima and Scenedesmus biomass enhanced the anaerobic digestion process and avoided inhibition caused by low C/N ratio of microalgae.

[1]  Y. Chisti.  Biodiesel from microalgae. , 2007, Biotechnology advances.

[2]  A. Shilton,et al.  Wastewater treatment high rate algal ponds for biofuel production. , 2011, Bioresource technology.

[3]  H. B. Gotaas,et al.  Anaerobic digestion of Algae. , 1957, Applied microbiology.

[4]  H. El-mashad.  Kinetics of methane production from the codigestion of switchgrass and Spirulina platensis algae. , 2013, Bioresource technology.

[5]  J P Steyer,et al.  Effect of organic loading rate on anaerobic digestion of thermally pretreated Scenedesmus sp. biomass. , 2013, Bioresource technology.

[6]  I. Angelidaki,et al.  Assessment of the anaerobic biodegradability of macropollutants , 2004 .

[7]  L. Laurens,et al.  Microalgae as biodiesel & biomass feedstocks: Review & analysis of the biochemistry, energetics & economics , 2010 .

[8]  J. C. Converse,et al.  Improved alkalimetric monitoring for anaerobic digestion of high-strength wastes , 1986 .

[9]  Freyr Sverrisson,et al.  Renewables 2014 : global status report , 2014 .

[10]  Beatriz Molinuevo-Salces,et al.  Evaluation of anaerobic codigestion of microalgal biomass and swine manure via response surface methodology , 2011 .

[11]  R. Samson,et al.  Improved performance of anaerobic digestion ofSpirulinamaxima algal biomass by addition of carbon-rich wastes , 1983, Biotechnology Letters.

[12]  Z. Rehman,et al.  Effects of thermal pretreatment on anaerobic digestion of Nannochloropsis salina biomass. , 2013, Bioresource technology.

[13]  J. C. García,et al.  Utilizacion agroindustrial del nopal , 2006 .

[14]  N. Bernet,et al.  Comparison of ultrasound and thermal pretreatment of Scenedesmus biomass on methane production. , 2012, Bioresource technology.

[15]  B. Ahring,et al.  Anaerobic digestion of swine manure: Inhibition by ammonia , 1998 .

[16]  O. Kruse,et al.  Microalgae as substrates for fermentative biogas production in a combined biorefinery concept. , 2010, Journal of biotechnology.

[17]  Cristina González-Fernández,et al.  Enhancing methane production of Chlorella vulgaris via thermochemical pretreatments. , 2013, Bioresource technology.

[18]  F. Rogalla,et al.  Biochemical methane potential of microalgae biomass after lipid extraction , 2014 .

[19]  Philip Owende,et al.  Biofuels from microalgae—A review of technologies for production, processing, and extractions of biofuels and co-products , 2010 .

[20]  Rafael Borja,et al.  A comparative kinetic evaluation of the anaerobic digestion of untreated molasses and molasses previously fermented with Penicillium decumbens in batch reactors , 2004 .

[21]  Hong-Wei Yen,et al.  Anaerobic co-digestion of algal sludge and waste paper to produce methane. , 2007, Bioresource technology.

[22]  W. Oswald,et al.  Biological conversion of light energy to the chemical energy of methane. , 1959, Applied microbiology.

[23]  H. Takeda.  Cell wall sugars of some Scenedesmus species , 1996 .

[24]  W. Owen,et al.  Fundamentals of Anaerobic Digestion of Wastewater Sludges , 1986 .

[25]  I. Sárvári Horváth,et al.  Co-digestion of different waste mixtures from agro-industrial activities: kinetic evaluation and synergetic effects. , 2011, Bioresource technology.

[26]  Paris Honglay Chen,et al.  Thermochemical treatment for algal fermentation , 1998 .

[27]  Roland Span,et al.  Anaerobic co-digestion of the marine microalga Nannochloropsis salina with energy crops. , 2013, Bioresource technology.

[28]  Willy Verstraete,et al.  Revival of the biological sunlight‐to‐biogas energy conversion system , 2009, Biotechnology and bioengineering.