Biogas production from sugarcane bagasse and marine algae using codigestion method

The sharp increase in energy consumption and the production of waste are the important environmental challenges. Anaerobic digestion of waste with methane and fertilizer production is an eco-friendly method. The codigestion of suitable substrates with the adequate mixing ratio removes the difficulties to single digestion. The aim of this study was to investigate the effect of codigestion of sugarcane and algae collected from the Caspian Sea on biogas production. To measure the biogas production in anaerobic digester, various treatments including sugarcane, algae and their mixtures were prepared in two ways, untreated and treated with ۱ M sodium hydroxide. In each digester, ۲۰ ml of inoculum (cow manure) and ۲ g of substrate were added and the final volume of digestion was increased to ۸۰ ml with water. The digester was incubated at ۳۷ °C for ۳۰ days. The volume of biogas production was measured during ۵ days intervals. The results was shown that the highest volume of daily gas production in the digester containing untreated sugarcane in the first ۵ days was ۲۲.۵۷% (v/v). Also, the lowest amount of daily gas in this digester was produced ۰.۲% (v/v) volume during the last ۵ days. The amount of biogas production in the digester containing sugarcane treated with ۱ M sodium hydroxide was appropriate, so that the amount of gas produced per day was ۵.۳۶% (v/v) during the last ۵ days. In addition, the results of daily biogas production in sugarcane and algae codigestion were average ۳.۱۸۴% (v/v), which in compare to the daily gas production during the ۳۰ days was more than in both digesters containing untreated and treated sugarcane. The results of the present study demonstrated that the codigestion of sugarcane and algae increases the production of biogas. Increasing the efficiency of biogas production using codigestion method requires further studies.

Keywords:

Biogas , codigestion , waste , sugarcane , marine algae