沼液变“废”为“肥”难在哪？

Core Viewpoint - The article discusses the challenges and potential solutions related to the treatment and application of biogas slurry produced from anaerobic fermentation of livestock manure, emphasizing the need for responsible management and innovative application methods [1] Group 1: Current Challenges - Biogas slurry contains nutrients like nitrogen, phosphorus, and potassium, which can be used as liquid fertilizer, but faces issues such as public perception, strong odor, and inadequate irrigation systems [1] - The treatment of biogas slurry has two main pathways: either to be discharged after meeting standards under the supervision of environmental management departments or to be used as liquid fertilizer with guidance from agricultural departments [1] Group 2: Application Techniques - The nutrient content of biogas slurry is relatively low, making it suitable for "water-fertilizer integration" application, which can be done even during fallow periods to maintain soil fertility [1] - During the rainy spring season, application should be timed to avoid rain, and optimized plans are necessary to prevent surface water pollution from liquid fertilizer [1] Group 3: Innovative Solutions - The emerging drone spraying technology offers high efficiency and uniform application, overcoming payload limitations and presenting significant potential for widespread adoption [1] - Drones can be used not only in farmland but also in forests and grasslands, suggesting a broader application scope for biogas slurry [1] - Relevant departments are encouraged to explore new issues and leverage advanced technologies to maximize the resource value of biogas slurry [1]