Comprehensive evaluation research of livestock and poultry waste treatment technologies in the ecological fragile areas of Northwest China

The applicability of livestock and poultry waste treatment technology is quite different in different regions. In order to comprehensively, objectively and scientifically screen out suitable livestock and poultry waste treatment technologies in Northwest China, the life cycle assessment, cost benefit analysis (CBA) and analytic hierarchy process (AHP) methods were coupled to establish a screening system for livestock and poultry waste treatment technologies in Northwest China. The system included five factors of technology, economy, climate, direct and indirect environmental impacts, with a total of 18 indicators. Taking the livestock and poultry waste treatment technologies in Lanzhou as an example, the applicability of the technologies of aerobic composting, anaerobic fermentation, and litter utilization were analyzed. The results showed that the comprehensive ranking of the applicability of livestock and poultry waste treatment technologies in Lanzhou City was litter utilization technology (72.21 points)>aerobic composting technology (71.55 points) > anaerobic fermentation technology (68.79 points). It was more suitable to use litter utilization technology in Northwest China. The environmental friendliness of litter utilization technology is obviously better than that of anaerobic fermentation and aerobic composting technologies. The use of aerobic composting and anaerobic fermentation technologies could generate additional profits for the breeding farm. This research could provide guidance for the construction and optimization of livestock and poultry waste treatment technology models in Northwest China.