Optimization of rice husk drying process with infrared dryer

One of the main goals of drying agricultural crop is reduction of the moisture content and obtain optimum moisture in order to get maximum storage time and reduction of crop losses in the processing stage. Regarding to new science application and different methods of drying, use of new methods such as drying with infrared ray is necessary to be studied. In this study in order to determine effect of air temperature at three levels of 40, 50 and 60 ° C and ultimate paddy moisture at levels of %7-8, % 9-10 and %11-12 (based on dry weight) on drying time and paddy husk percent of Tarom Hashemi was used rotary cylindrical drier of infrared in three replications. Besides, effect in three levels of temperature and moisture and two type crop of paddy and brown rice on some mechanical properties of the dried paddy were determined by instron apparatus in five replications. The results indicated that the studied factors temperature and moisture had a significant effect on drying time. However, temperature and moisture factors hadn’t significant effect on the husk present. Measurement of Mechanical properties of rice paddy after drying indicated that among three factors: type crop (paddy and brown rice), moisture and temperature; two factors of type crop and moisture were more effective on mechanical properties. The obtained results of the research showed that optimum temperature of drying and optimum ultimate moisture (based on dry weight) are 57/68 ° C degree and %7/5 and under such conditions optimum time of drying was 84/76 minutes so that husk percent, break time and force were %21/54, 4/24 sec and 33/92 N respectively, besides size of displacement up to break point was 0/34 mm.