Abstract
The objective of this study was to determine the optimal inclusion level of liquid egg hatchery waste for the anaerobic co-digestion of dairy cattle manure. A completely randomized experimental was applied, with seven treatments (liquid hatchery waste to cattle manure ratios of0: 100, 5:95, 10:90, 15:85, 20:80, 25:75 and 30:70), with five replicates (batch digester model) each. The evaluated variables were disappearance of total solids (TS), volatile solids (VS), and neutral detergent fiber (NDF), and specific production of biogas and of methane. Maximum TS and VS disappearance of 41.3% and 49.6%, were obtained at 15.5% and 16.0% liquid hatchery waste inclusion levels. The addition of 22.3% liquid hatchery considerably reduced NDF substrate content (53.2%). Maximum specific biogas production was obtained with 17% liquid hatchery waste, with the addition of 181.7 and 229.5 L kg-1TS and VS, respectively. The highest methane production, at 120.1 and 151.8 L CH4 kg-1TS and VS, was obtained with the inclusion of 17.5 and 18.0% liquid hatchery waste, respectively. The addition of liquid hatchery waste atratios of up to 15.5%in co-digestion with cattle manure reduced solid and fiber levels in the effluent, and improved biogas and methane production.
Highlights
The global demand for food is increasing every year under the pressure of the worldwide population growth
Treatments consisted of the anaerobic digestion of different ratios of liquid hatchery waste to dairy-cattle manure (0:100; 5:95; 10:90; 15:85; 20:80; 25:85; and 30:70, respectively), on total solid (TS) content basis, in five different biodigesters, totaling 35 experimental units
Nure of 15.5 and 16.0%, respectively, which resulted in 41.3% and 49.6% disappearance of total solids (TS) and volatile solids (VS) in the effluents relative to the substrates. These results indicate better degradation of solids during biodigestion with the inclusion of liquid hatchery waste, which increased TS disappearance in74.0%compared with the control treatment; while VS in 56.2%
Summary
The global demand for food is increasing every year under the pressure of the worldwide population growth. Solid waste consists of infertile eggs, unhatched eggs, dead chicks, dead or culled chicks, and eggshells, whereas liquid waste includes water used for cleaning the setters, hatchers, and hatchling handling areas (Araújo & Albino, 2011) This waste material has a high organic load, and contains, on average, 33.1% crude protein, 29% ether extract, 21.5% ash, and 28.8 MJ kg-1 gross energy (Glatz et al, 2011). This study aimed at determining the optimal addition level of liquid hatchery waste to dairy cattle manure submitted to anaerobic co-digestion to reduce solid and fiber content and to increase biogas and methane production
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
