Enhanced methane production from algal biomass through short duration enzymatic pretreatment and codigestion with carbon rich waste

Abstract

Anaerobic digestion of algal biomass faces problems of low digestibility due to cell wall resistance and inappropriate carbon to nitrogen ratio. In the present work a short duration method involving fungal crude enzyme based pretreatment of algal biomass was disclosed. The effect of fungal crude enzymes on algal biomass was assessed qualitatively through visual and microscopic observations and quantitatively through measuring algal biomass solubilization. Up to 50% biomass COD solubilization was observed within 150 min of pretreatment under optimal conditions. Subsequent anaerobic digestion of pretreated algal biomass showed production of 324.38 mL CH 4 g À1 VS fed as compared to 254.73 mL CH 4 g À1 VS fed from untreated algal biomass. Interestingly, methane yield increased up to 413.89 mL g À1 VS fed when pretreated algal biomass was codigested with cattle dung. On the other hand, sugarcane bagasse had a negative effect on algal biomass codigestion due to its poor digestibility. Overall, the present attempt showed promising results by improving methane yield from algal biomass though pretreatment and codigestion.

A method for simultaneous bioflocculation and pretreatment of algal biomass targeting improved methane production

“…Moreover, reports on cellulolytic action of A. lentulus crude enzymes on algal cell wall resulting in release of sugar from algal biomass, have recently been published by our group 18,19 .…”

“…Moreover, chemical and thermal pretreatment methods may render the algal biomass unsuitable for optimal biomethane production due to generation of inhibitory compounds during the pretreatment 17 . In contrast, the recently developed fungal crude enzyme based pretreatment of algal biomass 18,19 could provide an alternative to replace the conventional, cost and energy intensive processes. Our recent studies have established significant enhancement in the methane yield through fungal crude enzyme pretreatment of algal biomass 18,19 .…”

“…In contrast, the recently developed fungal crude enzyme based pretreatment of algal biomass 18,19 could provide an alternative to replace the conventional, cost and energy intensive processes. Our recent studies have established significant enhancement in the methane yield through fungal crude enzyme pretreatment of algal biomass 18,19 .…”

“…These enzymes could be utilized for pre-treatment of algae for improving its digestibility under anaerobic digestion 18,19 . Moreover, there have been some reports on utilization of fungal biomass for methane production through anaerobic digestion.…”

Current status of microalgae to produce Biogas through Pretreatment of lignocellulosic waste in the era of 21-Century

“…[46] Fig, 4. Solubilization and surface area effect the production of biogas by bacteria on inner organic matter [34,69]. The solution for this problem is shown in Fig, 5.…”