叶轮驱动式机收残膜水洗分选设备膜杂分离迁移机理的研究与参数优化

The project uses the residual film mixture in Xinjiang cotton field as the research object, which is twined and tied too seriously to be separated by machines. In order to solve the technical problem, project starts with the study of the shearing and breaking characteristics, basing on the liquid-solid two-phase flow theory , the principal component`s difference form of cracked material and the principle of sedimentation layering under external force disturbance, to put forward mixture separation method and water separation equipment scheme which are based on the residual film debris washing sedimentation layering of impeller driving and combination of water driving and carrying . Determine the optimal water washing separation technology scheme by studying on water washing dynamic settlement stratification and the flow carrying and migration law of the main components of residues in different sizes under different settlement scheme and different driving strength by doing experiments, constructing the main component fluid dynamics model through theoretical analysis, analyzing its motion characteristics by computer simulation, and identifying the main factors affecting the separation performance of the main components and their correlation and the parameters range. Design and manufacture the washing and sorting technology and device of residual film by mechanical recovery, through testing to obtain the influence law of the main parameters on the residual film water separation performance, constructing comprehensive evaluation and optimization model combined with production, obtaining the optimal parameter combination, to realize the functions of membrane separation, migration, collection and other functions effectively. The results are of great significance for the recovery and reutilization of machine collecting residual film and the separation and transfer of complex materials.

项目以新疆秋季棉田机收残膜混合物为研究对象，针对其缠绕打结无法机械化分离清选的技术难题，从其剪切破结特性的研究入手，依据液固两相流理论和破解后物料主成分的形体差异大，外力扰动沉降分层的原理，提出基于叶轮驱动的残膜碎片水洗沉降分层和水介质驱动携带相结合的膜杂分离方法和水洗分选设备方案，试验研究不同尺寸残膜物料主要成分在不同沉降方案和不同叶轮驱动转速下其水洗动态沉降分层及其水流携带迁移规律，理论分析构建主成分流体动力学模型，计算机仿真分析其运动特性，明确影响其主要成分分离性能的主要因素及其相互关系及参数变化范围，确定较优的水洗分离技术方案。设计研制机收残膜水洗分选的工艺与设备，试验获得其主要参数对残膜物料水洗分选性能的影响规律，结合生产构建综合评判优化模型，获取较优参数组合，有效实现膜杂分离、迁移、收集等功能，其成果对机械化残膜回收利用与复杂形体混合物料分离迁移方法及相关理论研究意义。

项目针对机收残膜混合物缠绕打结无法机械化分离清选的技术难题，从其剪切破结特性的研究入手，依据液固两相流理论和破解后物料主成分的形体差异大，外力扰动沉降分层的原理，设计了膜秆混合物剪切破结装置和水洗分选设备。项目构建了残膜和棉秆的动力学和运动学模型，理论分析了曲面V型滚刀式剪切机构的力学特性，搭建了膜秆混合物剪切破结试验装置，通过台架试验分析确定了影响剪切破结性能的主次因素，构建各性能指标影响因素的回归方程。对于破结后的残膜混合物，项目通过搭建地膜与棉秆悬浮水力特性试验台，开展外部流场和地膜与棉秆物料属性的单因素试验和正交试验，明确了其水洗动态沉降分层及其水流携带迁移规律，理论分析了构建了残膜和棉秆流体动力学模型，建立了影响因素与响应指标之间的多元拟合回归方程，确定了较优的水洗分离技术方案。在此基础上，提出基于灌溉用引水渠中的水为介质的膜秆分离方案，设计研制机收残膜水洗分选的工艺与设备。项目主要开展的研究内容与结论如下：通过剪切试验研究棉秆主干部位、地膜包裹层数和加载速度对膜秆混合物剪切强度的影响，当取样部位为棉秆主干底部，地膜包裹层数为8层时，剪切强度达到最大值为4.25MPa；当剪切破结装置输送辊线速度0.993m/s，剪切工作角度152.8°，剪切器主轴转744.8r/min时，碎膜率77.44%、碎秆率87.78%；地膜与棉秆分离的最优参数组合为叶轮转速202 r/min，地膜面积为1271.4 mm2，棉秆长径比为13，相对应的地膜与棉秆驰豫时间差和最大垂向位移差分别为4.20 s 和22.1 cm；水洗分选设备的最佳参数组合：导流板安装角度为33.75°，膜秆喂入量为67.452 个，膜秆回收网安装位置为24 cm，位移差为25.76 cm，膜秆损失率为10.00%，回收网中含杂率为3.72%。迄今为止，该项目主要研究内容已经全部完成，授权发明专利2项，实用新型授权4项；发表SCI检索论文1篇，EI检索论文3篇，核心期刊论文3篇；科研竞赛国家银奖1项，省部级2项；培养青年教师和研究生6人次。项目解决了残膜混合物料的剪切破结和分离问题，对残膜回收利用与复杂形体混合物料分离迁移研究提供理论参考。