With the continuous recognition of green, organic and non-polluting products, organic fertilizers play an increasingly vital role in agricultural production. Among them, hydrochar-based organic fertilizer has attracted widespread attention recently. The present study evaluated the potential of digestate from anaerobic digestion of food waste for the preparation of hydrochar-based organic fertilizer by straw-based, FeCl3-catalyzed hydrothermal carbonization (HTC). Under the optimal conditions, a hydrochar-based organic fertilizer with > 25 wt% humus content and limited pollution risk was successfully prepared. The pot experiment demonstrated the feasibility of improving the physicochemical properties of red soil and promoting crop growth after adding hydrochar in place of commercial fertilizer. In addition, the function of zeolite on nutrient recovery in hydrothermal liquid (HTL) was analyzed, and preparing the slow-release organic fertilizer by mixing the nutrient-rich zeolite with hydrochar in a mass ratio of 1:4 was proposed. This work has significant implications for achieving the efficient resource recovery of digestate.

中文翻译：

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通过水热处理从餐厨垃圾沼渣中高效回收资源并用作有机肥料


随着绿色、有机和无污染产品的不断认可，有机肥料在农业生产中发挥着越来越重要的作用。其中，水炭基有机肥近年来引起了广泛关注。本研究评估了食物垃圾厌氧消化液通过秸秆基 FeCl3 催化的水热碳化 （HTC） 制备水炭基有机肥的潜力。在最佳条件下，成功制备了腐殖质含量为 > 25 wt% 且污染风险有限的水炭基有机肥料。盆栽实验证明了添加水炭代替商品肥料后改善红壤理化性质和促进作物生长的可行性。此外，分析了沸石对热液 （HTL） 养分回收的功能，提出了将营养丰富的沸石与水炭以 1：4 的质量比混合制备缓释有机肥。这项工作对于实现沼渣的高效资源回收具有重要意义。