Manure separation is a process where a fraction of slurry particles is isolated by one of several mechanical separation processes (Burton, 2007). Storage of the liquid fraction may result in lower N2O emissions than untreated slurry if crust formation is prevented. However, N2O emissions from the solid fraction during storage can be high (Fangueiro et al., 2008), and thus overall N2O emissions during storage may increase significantly after separation without additional measures. Separate storage of the liquid and solid fractions after manure separation have in most cases, resulted in lower CH4 emissions (Table 6). Likewise, combined CH4 and N2O emissions from storage of both separation products have usually, but not always, been lower than from untreated manure (Dinuccio et al. 2008; Mosquera et al., 2011). Slurry separation requires additional measures to achieve GHG mitigation during subsequent storage: cover solid and liquid fractions or anaerobic digestion of solid fraction (Sutaryo et al., 2012).

Source: AnimalChange (project supported by the EU-FP7)

DELIVERABLE 6.2. Deliverable title: Report on the extent to which manure management might help decrease GHG gas from animal agriculture.