Effect of multiple product extractions on bio-methane potential of marine macrophytic green alga Ulva lactuca

• Published in: Renewable energy 2019-03, Vol.132, p.742-751
• Main Authors: Mhatre, Apurv, Gore, Suhas, Mhatre, Akanksha, Trivedi, Nitin, Sharma, Manju, Pandit, Reena, Anil, Annamma, Lali, Arvind
• Format: Article
• Language: English
• Subjects: Anaerobic digestion; Biomethane potential; Macroalgae; Sequential extraction; Ulva sp
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2018.08.012

Biomethane Potential (BMP) of green macroalga Ulva lactuca post extraction of sap, ulvan and protein was analysed in batch studies. Extraction was performed in two different ways (individual and sequential) to understand the effect of removal of these components on methane yields. Both the treatments resulted in enhanced biomethane production in most of the treated residues, however, the highest methane yield of 408 ± 20.02 ml CH4 g−1 VS (70.93% of theoretical) was observed in sap and ulvan removed residue (batch VI). The methane production rates improved after both the treatments (0.15–0.28 day−1 for untreated and treated batches). This corroborates well with the fact that high protein and sulphate content are major inhibitors in anaerobic digestion (AD) of U. lactuca and their removal leads to improved methane yields. Sequential extraction of value-added products prior to the AD process not only improves biomass amenability and respective methane yields but also makes the overall process more efficient and viable. [Display omitted] •Enhanced amenability of Ulva lactuca biomass post sequential treatment.•Rapid anaerobic digestion with increased substrate utilization (upto 46%).•Improved biomethane yields (∼2 folds) from treated residues.•Sequential extraction of bio-products for biorefining of Ulva lactuca.