ANAEROBIC DIGESTION AND CO-DIGESTION OF POULTRY LITTER SUBMITTED TO DIFFERENT REUSES

ABSTRACT Considering the constant increase in the waste generation from poultry and pigs’ husbandries, the main contributions of this study were to verify the potential of biogas production through the anaerobic digestion and co-digestion of the residues generated by these two activities, as well as to highlight the recovery of the nutrients contained in the obtained digestate. The wastes used were poultry litters after six, seven and eight production lots, as well as the sifted wastewater from one Piglets Producer Unit (PPU). Higher biogas production (p <0.05) was observed in the treatments in which anaerobic codigestion was used with the swine wastewater (SW): 0.179; 0.158 and 0.117 m3 per kg of total solids (TS) added for poultry litters with six, seven and eight lots, respectively. It was concluded that the anaerobic co-digestion between the poultry litter and sifted swine wastewater is the best option for energy and nutrient recycling. No positive relationships were observed in the increase in the number of reuses of litter in the production of biogas and in the concentration of nutrients in the digestate.

摘要：鉴于家禽与生猪养殖业废弃物产生量持续增长，本研究的主要贡献在于验证了利用两类养殖活动产生的残渣开展厌氧消化及厌氧共消化生产沼气的潜力，并阐明了回收所得消化物中营养物质的可行路径。本试验所用废弃物包括经6、7、8批养殖生产后的家禽垫料，以及某仔猪生产单元（PPU）经筛分处理的养殖废水。试验结果显示，相较于单一厌氧消化，添加猪粪废水（SW）的厌氧共消化组沼气产量显著更高（p<0.05）；对应6、7、8批养殖垫料的处理组，每千克添加总固体（TS）的沼气产量分别为0.179、0.158及0.117立方米。研究结论表明，家禽垫料与筛分猪粪废水的厌氧共消化是实现能源与营养物质循环利用的最优方案。此外，本研究未发现家禽垫料重复使用次数的增加与沼气产量及消化物中营养物质浓度之间存在正向关联。