Livestock manure use for biogas production in Latvia

Abstract

The raw material distribution used for the production of biogas in Latvia in 2019 has been identified in the plants where manure is used as feedstock. The focus of the study was on quantification of processed manure in biogas and estimation of the exploited potential. It has been established that in the production of biogas mainly dairy cow slurry, calf and heifer solid manure, considering that these animals are not placed in pastures, pig slurry from large farms and laying hen manure from cage housing are used. In addition, various other biomasses are used: maize silage, animal fodder residuals, animal slaughterhouse bio waste, sewage sludge, molasses, etc. The mass of other biomass may represent up to 50% of the amount of manure processed. In Latvia in 2019, 37 biogas plants used manure as feedstock. The total amount of manure processed was 840.8 thousand tonnes. Of these, 34.7% were cattle slurry and litter, 44.1% was pig slurry and 61.9% was laying hen manure. This means that the possibilities for manure processing in biogas because the capacity is not currently exhausted can be significantly increased in the future due to intensification of the livestock farming.