Anaerobic co-digestion of dairy cattle manure and pear waste

Anaerobic co-digestion of pre-treated dairy cattle manure (LCM) with pear waste after a storage period (PLF) was tested at four inclusion levels: 0%, 25%, 75% and 100%. Inclusion levels consisted in the replacement of the volatile solids (VS) from the LCM with the VS from PLF keeping the organic loading rate around 1.1 ± 0.4 g SV L−1 d−1. The introduction of the co-substrate clearly enhanced methane production rate (MPR) in comparison to single substrate (phase I) as phases II and III, respectively, achieving values 1.3 and 2.8 times higher than phase I. The overall performance was optimized for the mixture 25:75 (LCM:PLF; v:v). Moreover, storage of pear waste did not compromise its use in AD. This fact is important once it can improve waste management from pear production through its valorisation as co-substrate in AD process.