Experimental Study On Process Parameters Of Downstream Corn Drying In Cold Regions

Heilongjiang province is an important grain production base.In the process of commodity grain storage,if handled improperly,the quality of commercial grain will be greatly damaged,the germination rate will be reduced,or even completely damaged.With the limit of long-term and climatic conditions,corn needs to be dried in winter storage.Only fast down to safe moisture the quality of corn can be ensured.Therefore,in order to solve the problems of low drying efficiency,energy consumption and drying quality in the drying process of corn in the northern cold field,analysis the cold ground corn drying technological process,improve the system automatic control test system,the hardware and software of the system and automatic control test system was made numerical simulation analysis,and verify its improved rationality.The experimental study was carried out on the improved test platform.The main research focuses on the following aspects:(1)Based on the cold ground corn drying characteristic and basic structure of test bed,with 1-wire bus technology,finish the set up of the testing system of temperature and humidity sensor,using Lab VIEW monitor development platform to finish the design of system software.The automatic control test system is used for simulation analysis,the applicability and rationality of the design of the test bench are verified.(2)With the influence factors of hot air temperature,hot wind speed,the drying time,initial moisture content,the drying rate and crack rate as a target for the single factor experiments.By single factor test results of variance analysis,hot air temperature(80℃～120℃),hot wind speed(0.5m/s～1.5m/s)and the drying time(90 min～110 min)for the significant influence factors,provides the parameter basis for the quadratic general rotary combination experiment.(3)Using ternary quadratic general rotary combination test method,three sets of significant factors is obtained by single factor,with the drying rate,unit energy consumption,corn quality as evaluation index,use MATLAB for data processing and analysis of each evaluation index and draw the response surface graph.The target function is determined directly by the parameters.Each index regression mathematical model is established,rendering the use linear efficacy coefficient method,weighted comprehensive evaluation method and comprehensive optimization of drying process,to determine the order of influence dry comprehensive evaluation index for:dry hot air temperature>time>hot wind speed.Optimum parameter combination of cocurrent drying process is:103 ℃ hot air temperature,hot wind speed 1.5 m/s,the drying time of 100 min.Under the condition of the process parameters,the efficiency of drying can be effectively improved,save energy,reduce nutrient losses in corn drying process and achieve the purpose of cold corn drying quality,provide theory for downstream dry cold northern corn production base.