Authors

Abstract

Solid-liquid separation is essential for utilizing livestock and poultry manure, impacting greenhouse gas emissions and pollution control. This study aimed to address the high water content and low efficiency issues in screw extrusion solid-liquid separation technology. A screw separator was designed, and a Box-Behnken test scheme was used to optimize parameters with dairy manure as the test object. The study identified extender length, screw rotation speed, and counterweight mass as the influencing factors, with extrudate water content and solids extraction rate as evaluation indices. A quadratic regression model was established to describe the relationships between the influencing factors and evaluation indices. Optimal parameters were determined as: extender length=10 cm, screw rotation speed=55 r/min, and counterweight mass=34.73 kg. The predicted extrudate water content was 65.44 %, and solids extraction rate was 2.39 m³/h. Validation tests showed an average extrudate water content of 67.71 % and solids extraction rate of 2.10 m³/h, with relative errors of 3.3 % and 9.6 % respectively. The model's reliability was confirmed, providing a reference for designing livestock and poultry manure screw extrusion separators.

Abstract in Chinese

固液分离是畜禽粪便资源化利用的关键共性环节，对控制温室气体排放和环境污染治理具有重要意义。针对螺旋挤压固液分离技术存在的挤出物含水率偏高、处理效率较低的问题，本研究设计了一种螺旋挤压脱水装置，以奶牛粪为试验对象，采用Box-Benhnken试验方案开展了参数优化研究。以延长器长度、螺杆转速、配重重量为影响因素，以挤出物含水率和固形物提取率为考核指标，建立了影响因素与考核指标之间的二次回归模型。通过多目标优化函数，确定一组最佳参数组合为：延长器长度=10cm，螺杆转速=55r/min，配重重量=34.73kg，此时挤出物含水率预测值为65.44%，固形物提取效率预测值为2.39m³/h。验证试验结果表明，在最优参数组合下，挤出物含水率均值为67.71%，与预测值相对误差为3.3%。固形物提取效率均值为2.10 m³/h，与预测值的相对误差为9.6%。两个考核指标的实测值与理论预测值均＜10%，表明建立的二次回归模型可靠，可用于参数优化。研究结果可为畜禽粪污螺旋挤压分离机的设计提供参考。