Parameter Optimization And Experimental Research Of Rotary Drum Dehydrating Machine

Green removal is a key process for the formation of green tea shape and quality.Its purpose is to inactivate the enzyme activity and inhibit the enzymatic reaction of polyphenol oxidase by high temperature,which directly affects the quality of tea.At present,the electric roller type rotary drum dehydrating machine is widely used,but there are some problems,such as low utilization of heat energy,low quality and low output.Based on the analysis of the key structure parameters and the characteristics of tea particles in rotary drum dehydrating machine,the research group carried out research on the key geometric parameters and drum speed of 6CST-60 electric heating rotary drum dehydrating machine,and carried out the numerical simulation of the process by EDEM software to obtain the best working parameter combination which is beneficial to the tea green removing process,and to provide a theoretical reference for improving the green removing quality of the rotary drum dehydrating machine.The main work and achievements of this paper are as follows:(1)This paper analyzes the main transmission mechanism of the existing machine,including rack and pinion,gear pair,worm and worm gear,chain,friction wheel and so on.Combined with the actual operation characteristics and working conditions of the roller type rotary drum dehydrating machine,the friction wheel is selected as the transmission part,which has the advantages of supporting function in addition to transmission,and the corresponding friction wheel parameters and materials are designed.(2)Through Solidworks software,the virtual prototype of 6CST-60 type electric heating roller type rotary drum dehydrating machine was established,and the process of green removal was numerically simulated in EDEM.The movement process of tea particles in the drum was analyzed,and the kinematic and dynamic curves of tea particles under different drum geometric parameters(guide vane angle,number of guide vane plates)and cylinder speed were obtained,it provides a theoretical basis for the optimization of the parameters of the rotary drum dehydrating machine.(3)Taking the drum speed,guide vane plate angle and guide vane plate number as the influencing factors,and the appropriate rate and deterioration rate of the green leaf as the evaluation index,the quadratic orthogonal rotation combination test with three factors and three levels was carried out.Design-Expert software is used to process and optimize the test results.The test results showed that the order of influence on the two evaluation indexes was cylinder speed,guide vane angle and guide vane plate number.When the optimum parameter combination was drum speed 27.09 r/min,guide vane plate angle16.4 ° and guide vane plate number 5.1,the appropriate rate of cyaniding leaf was 96.18%,the deterioration rate was 1.28%,and the quality of cyaniding is better.(4)Taking 6CST-60 electric heating rotary drum dehydrating machine as the research object and famous green tea Lu'an Guapian Tea as the experimental material,the validation test was carried out on the green tea processing production line of tea processing base in Anhui Agricultural University.The rotation speed of the roller was set at 27 r/min,the angle of guide vane plate was 16 ° and the number of guide vane plates was 5.The moderate rate of green killing leaves was 94.87% and the deterioration rate was 1.31%.The verification test and optimization results were basically consistent.