Anaerobic fermentation liquid from food waste contains abundant nutrients, such as volatile fatty acids (VFAs) and NH₃–N, which are promising nutrient sources for plant growth. Here, we report a novel integrated technique for the simultaneous recovery of C and N sources from anaerobic fermentation liquid. VFAs and NH₃–N extracted from anaerobic fermentation liquid were synthesized and converted into layered double hydroxides (LDHs) and NH₄HCO₃, respectively, for subsequent use as soil amendments to provide external C and N to plants. The X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy/energy dispersive X-ray spectroscopy results suggested that VFAs were successfully intercalated within the LDH, and the composite (VFA-LDH) exhibited good sustained release performance. In the VFA-LDH synthesis process, the concentrations of chemical oxygen demand, VFAs, and NH₃–N were reduced by 49.4%, 27.9%, and 43.6% in the anaerobic fermentation liquid, respectively. In addition, VFA-LDH and NH₄HCO₃ promoted increased soil fertility, including organic matter content, cation exchange capacity, and N and P contents. Overall, the developed technique exhibits great potential as an anaerobic fermentation liquid treatment and nutrient acquisition method.

中文翻译：

---

营养获取的创新综合技术：从餐厨垃圾厌氧发酵液中同时回收碳和氮源

来自食物垃圾的厌氧发酵液含有丰富的营养物质，例如挥发性脂肪酸（VFA）和NH ₃ -N，它们是植物生长的有希望的营养物质来源。在这里，我们报告了一种从厌氧发酵液中同时回收C和N源的新型集成技术。合成了从厌氧发酵液中提取的VFA和NH ₃ -N，并将其转化为层状双氢氧化物（LDHs）和NH ₄ HCO ₃分别用作土壤改良剂，为植物提供外部碳和氮。X射线衍射，傅立叶变换红外光谱和扫描电子显微镜/能量色散X射线光谱结果表明，VFA已成功插入LDH中，并且复合材料（VFA-LDH）表现出良好的缓释性能。在VFA-LDH合成过程中，厌氧发酵液中的化学需氧量，VFA和NH ₃ -N浓度分别降低了49.4％，27.9％和43.6％。此外，VFA-LDH和NH ₄ HCO ₃促进了土壤肥力的增加，包括有机质含量，阳离子交换能力以及氮和磷含量。总体而言，开发的技术作为厌氧发酵液处理和养分获取方法具有巨大的潜力。