Vermicomposting is an efficient technology to treat organic wastes and recover nutrients for agricultural purposes. The aim of this work was to assess the feasibility of vermicomposting to treat onion waste and the resulting vermicompost as an agricultural input. Onion waste from the food industry was mixed with cow dump and vermicomposted for 154 days at the pilot scale. The evolution of temperature, moisture, pH, electrical conductivity and total nitrogen was monitored during the vermicomposting process. Finally, the vermicompost was characterized to assess its potential use in agriculture. The vermicomposting process was carried out at moisture around 85% and maximum temperature of 33 °C. The pH decreased throughout the process, while the electrical conductivity increased. Total nitrogen concentration decreased during the first days but then was constant. The final vermicompost was a mature material (C/N = 13), with considerable carbon content (15.7%), lightly basic and with low electrical conductivity. Nutrient equilibria were 1:8:3 with appreciable content of other nutrients such as Ca, Mg and S. Toxic elements were in low concentration and below the legal threshold. The vermicomposting of onion waste with cow dump is a feasible technology to treat this waste and produce a valuable agricultural input to close the nutrient circle.

中文翻译：

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通过ver堆肥回收洋葱废物：营养素回收和农艺评估

com堆肥是一种有效的技术，可以处理有机废物并为农业目的回收营养。这项工作的目的是评估ver堆肥处理洋葱废物的可行性以及由此产生的ver堆肥作为农业投入品的可行性。将食品工业的洋葱废料与牛粪混合，并在试验规模上进行了154天的糊涂。在ver堆肥过程中监测温度，水分，pH，电导率和总氮的变化。最后，thecompost的特征在于评估其在农业中的潜在用途。com堆肥过程是在约85％的水分和33°C的最高温度下进行的。在整个过程中，pH降低，而电导率增加。总氮浓度在开始的第一天下降，但随后保持恒定。最终的ver堆是一种成熟的材料（C / N = 13），具有相当大的碳含量（15.7％），弱碱性和低电导率。营养平衡为1：8：3，其他营养素（例如Ca，Mg和S）的含量也相当可观。有毒元素的浓度较低且低于法定阈值。用牛粪对洋葱废物进行堆肥处理是一种可行的技术，可以处理这种废物并产生有价值的农业投入物，从而关闭养分循环。有毒元素浓度低且低于法定阈值。用牛粪对洋葱废物进行堆肥处理是一种可行的技术，可以处理这种废物并产生有价值的农业投入物，以关闭养分循环。有毒元素浓度低且低于法定阈值。用牛粪对洋葱废物进行堆肥处理是一种可行的技术，可以处理这种废物并产生有价值的农业投入物，从而关闭养分循环。