Design And Experimental Study Of Straw Fiber Grinding Device

Straw fiber is an important raw material for the manufacture of seedling pot,biodegradable mulch film and tableware box,and is one of the key links in the high-value utilization of straw.At present,the production of straw fiber is mainly a combination of chemistry and physics,most of the straw fiber is obtained by the production method of traditional paper and pulp,there are some problems such as huge production equipment,complex technology and difficult to control the PH of straw fiber after production.Therefore,this paper designed a pure physical method to prepare rice straw fiber grinding and crushing device,the research results obtained are as follows:(1)On the basis of analyzing the material properties of rice straw,the whole structure of the straw fiber grinding device was designed.The design includes spiral feeding shaft design,grinding wheel clearance adjustment device design,spindle design and motor selection,grinding wheel selection,etc.Using Solid Works software to complete the solid modeling of straw fiber grinding preparation device,in order to determine the reasonable layout and working mode of each mechanism and device,verify the rationality of machine design and principle feasibility.(2)On the basis of the overall design of the straw fiber grinding preparation device,the key components including spiral feeding shaft and grinding wheel were statically analyzed,and the fatigue stress points were obtained through the stress analysis diagram,and solutions were adopted to verify the reliability of the work;EDEM analysis software was used to simulate the grinding process of straw material,determine the screw shaft working parameters,through the analysis of particle distribution characteristics and movement speed of the material,the process of straw crushing and fiber formation was studied.The simulation results showed that: the motion track of material particles is continuous and the distribution law is reasonable,the highspeed rotation of grinding wheel and rotation of feeding screw axis enhance the grinding and crushing effect of straw materials,and achieve the purpose of straw fiber preparation.The working parameters of the screw feeding shaft were determined as follows: the rotating speed of the screw feeding shaft was 44 r/min,the inner diameter of the screw was 25 mm,and the pitch of the screw was 40 mm.(3)In order to test the working effectiveness and efficiency of the straw fiber grinding preparation device,a straw fiber quality evaluation method was innovated,the prepared straw fiber is loaded into a special mold,which is pressed under a certain pressure and time to obtain the test sample,after drying under 60℃,the tensile index of the samples was determined by computer controlled Instron 5944 electronic universal tensile and compression tester,and the fiber quality was evaluated indirectly.In order to verify the scientific rationality of the method,in this paper,through extracting image grid,binarization processing method to establish sample test block pore channel model,analysis and straw fiber channel coefficient ratio test sample piece of the relationship between the tensile index,mechanism analysis showed that compared with conventional image analysis method,this method is feasible and reliable,easy to operation.(4)On the basis of single factor test,spiral feeding shaft speed,grinding wheel clearance and grinding wheel speed were selected as test factors,the tensile index of straw fiber and the kiloelectric yield of grinding device were used as evaluation indexes,and the three-way quadratic regression orthogonal combined experimental design was combined with response surface analysis,the effects of rotating speed of spiral feeding shaft,grinding wheel clearance and grinding wheel speed on tension index and kilowatt-hour output were tested,the optimized process and working parameters are as follows: grinding wheel clearance is 0.21 mm,grinding wheel speed is 1250r/min,screw feeding shaft speed is 40r/min.The experimental results show that the straw fiber grinding device can meet the technological requirements of straw fiber preparation after optimizing the experimental parameters.This study can provide theoretical reference for the design of straw fiber grinding device and straw fiber preparation method.