Macroalgae as Co-Substrates in Anaerobic Digestion Processes of Pig Slurry

Abstract

Anaerobic Digestion (AD) has proven to be very useful for the treatment of effluents with high organic load and the generation of methane. At the same time, the use of co-substrates increases the yield of methane in AD, which can be translated into both environmental and economic benefits. In this research, the comparison of methanogenic yields of three co-substrates in the AD of pig manure was carried out: macroalgae, aquatic plants and terrestrial plant. In order to do this, Biochemical Methane Potential (BMP) determination was performed. The results show that using macroalgae as a co-substrate, it is possible to obtain 157,2 ± 66,1 mlCH4/gVS, around three times the volume of methane obtained comparing it with an AD using only pig slurry. Thus, the use of macroalgae is proposed to increase methanogenic yield in AD processes.