Experimental Study Of Dehumidification System For Storage

Air dehumidification is a very important issue in production. Low humidity response of storage requirements need to choose a suitable dehumidifying technology. In order to prevent the seeds from inactivation which caused by mildewed, this paper, based on literature retrieval and according to different dehumidification principles, puts forward the scheme of the dehumidifying system of the seed storage. The dehumidifying technology on the system, the system model, the form of air supply pipeline and other aspects were studied. Further details are present as follows:(1)The existing dehumidification technologies are clarified and the working principle and structure of dehumidification equipment are analyzed. Their advantages and disadvantages are introduced. Besides their future development directions are presented.(2)In order to select the suitable method of dehumidification for the storage, the test platform for storage of seeds is built. In this paper, the experimental study is carried out by changing the temperature of 5?, 15?, 25?, and the dehumidification method of refrigeration dehumidification and desiccant rotary wheels. The effect of dehumidification is characterized by the ability of dehumidification, the efficiency of dehumidification and the uniformity of the humidity field. The results show that the efficiency of refrigeration dehumidification method is 0.073g/(kg·h·k J), and the uniformity of humidity field is 6.58%, and the effect of desiccant is better at 25?. At 15? and lower temperature, the desiccant rotary wheels capacity is 3-6 times of refrigeration dehumidification, and the desiccant efficiency is 0.0034g/(kg · h · k J) and 4 times as much as refrigeration dehumidification at 5?. In this temperature environment, the desiccant rotary wheels way is more suitable. The research results provide a reference for the design of dehumidification system for the storage.(3)In this paper, the two-dimensional simulation model of the storage wheel desiccant system was established by using the finite element analysis software COMSOL Multiphysics. Based on the model of dilute species transport and the k-? model, the humidity field in the process of the desiccant is simulated, and the change and distribution of humidity in the storage room are obtained. The highest air flow velocity and pressure is between the air inlet and air outlet. The humidity distribution in the box body is relatively uniform, and the difference between the highest value of water vapor mole concentration and the lowest value is only 0.04mol/m3. The ambient temperature is 5?, 15?, 25?, with the increase of temperature, the rate of dehydration is accelerated, the water vapor mole concentration is increased and the uniformity of the humidity distribution is decreased. By comparing with the test results, the test results are in agreement with the simulation results, and the model is accurate. The results of this study have a certain reference value for the design of the desiccant system for storage.(4)In order to improve the working performance of dehumidification system for the storage and uniformity of the dehumidify homogeneity of preservation environment, a set of pipeline type wheel dehumidifying device is designed. And the dehumidifying effect of the modified system are tested and analyzed. By increasing pipeline type passage of dry air, the pattern of indoor air flow is rearranged from middle-in and bottom-out to pipe-in and bottom-out. In this paper, the experimental study is carried out by changing the pipeline location, pipe diameter, and the number of holes on pipes. The experimental results show that, when the pipeline is located in 0.65 m, the pipe diameter is 40 mm,the number of holes on pipes is 20, the capacity and efficiency of the desiccant is optimal. When the pipeline is located in the lower part of the box, the pipeline diameter is 50 mm, the number of holes is 20, the relative humidity distribution is the most uniform. The number of holes on pipeline has the greatest influence on capacity and efficiency of dehumidification, and the position of the pipeline has the most significant effect on the uniformity of humidity. The research results provide a reference value for the optimization design of dehumidification system for the storage.The results show that the dehumidification system of seed storage can adapt dehumidification requirement in low temperature environment, achieve the dehumidification function of the design requirements. The simulation model of the rotary desiccant system of the seed storage warehouse was established. The flow field inside the warehouse is optimized. The humidity control requirements of seed storage warehouses are satisfied.