Experimental Study On The Dried Preservation Storage Technology Of Late Indica Rice In The Warehouse

In the majority of Southern region of China, summer storage of late indica rice is always an insurmountable difficulty. In this paper, using the methods of by reducing moisture of late indica rice and lowering storage temperature, we study the deterioration process of rice, and develop the applicable ventilation drying equipment and refrigeration equipment for big warehouse. It provides solutions for acquisition and storage of paddy rice with high moisture content.In this study, small samples was used to simulate the drying experiments and verify the feasibility and equipment parameters; then self-designed dehumidifier was used to low water under closed circulation in the practice bin drying test and let average water content to drop the safe storage in full bin. To keep long period safe storage of rice, we studied the low temperature storage of grain and CFD technique was introduced to study transferring heat, and following fixed diversion ventilation to reach fixed-point cooling purpose. It will energy saving and fast.Simulating the drying test results showed that drying temperature controlled below 40℃ and moisture controlled range from 11.0%-13.6% effectively improved the rate of head milled rice, food processing and eating quality and conducive to rice preservation. In low humidity and humidity conditions of wet paddy drying, temperature is the most important factors which affected the rice milled rice rate and 40℃ is a watershed, and about 40℃the highest milled rice rate. When the temperature is higher than 40℃, it has a great influence on the rate for milled rice and rice rapid dehydration, which will cause internal grain layer fracture and head milled rice rate decreased rapidly. When the temperature is below 40℃, velocity of reducing moisture content will decrease. Overall, high wet rice lowering moisture rice has little effect on head milled rice rate. Because high wet rice lost moisture slowly, the velocity of reducing moisture content is also slow. From actual production application of 40℃ for drying is more appropriate, it is best to adjust the ventilation humidity in the different stages, while maintain the high rate of head milled rice and rapid reducing moisture content of rice.Based the original ordinary ventilation equipments, the new ventilation and dehumidification equipment and double cold source grain cooling machine were added introduced the temperature and dehumidification function, which can control temperature and humidity of the air entering the chamber and can more quickly and effectively adjust the structure of the cabin temperature and humidity. It has important significance for grain storage; At the same time, double cold source grain cooling machine also reduce energy consumption and make full use of energy of groundwater cooling and condenser heat.The whole warehouse reduces moisture content need to increase the grain temperature and will consume a lot of energy. After reducing moisture, downregulating the grain temperature also need consume a lot of electricity energy. So the temperature of reducing moisture can not be too high. When the average grain temperature of the whole warehouse is more than 23 ℃, the grain temperature is not high and reducing the ventilation is suitable, and the rice will not produce the deterioration and the ventilation efficiency is improved obviously comparing with the low temperature situation. Because store drying is connected pipe ventilation equipment with barn, which form a closed circulatory system and it is little affected by the external environment, so it can ventilate and reducing moisture content under various environmental conditions. Analyzing the heat into the way and the range by the method of computational fluid dynamics (CFD) and deciding fixed cooling, it will save a lot of cooling capacity and can quickly and efficiently to achieve the purpose of grain storage in low temperature; while preserving the rice in winter cooling form cold core, and pressing lid flow ventilation can save cooling capacity 52.17% comparing with existing ventilation system. It can keep the original processing quality of rice and edible quality and do not need most of the grain conventional ventilation under the high and low temperature repeatedly.