Effects of ceramsite on methane and hydrogen sulphide productions from macroalgae biomass

The easy acidification and high hydrogen sulfide (H2S) production during anaerobic digestion of macroalgae limited its application in biomethane production. In order to investigate the effects of ceramsite on methane and H2S productions during anaerobic digestion of macroalgae, batch experiments of Macrocystis pyrifera were carried out. Four groups named C0, C1, C2 and C3 added with 0, 1.5, 3.0 and 4.5 g/gsubstrate of ceramsite, respectively, were studied and compared. The highest cumulative methane yield of 286.3 mL/gsubstrate is obtained in C2, which is 40.11% higher than that of C0. The cumulative H2S yields of C1, C2 and C3 are 32.67%, 44.66% and 53.21% lower than that of C0, respectively. Results indicate that ceramsite addition permits higher methane yields, shorter lag-phase time and lower H2S yields during anaerobic digestion of Macrocystis pyrifera.