What is the Drying Temperature of the Dehumidifying Dryer?

Since most engineering plastics are hygroscopic, coupled with the influence of weather and regional climate, it is easy to cause excessive moisture in the plastic pellets and fail to achieve the molding effect. In addition, the plastic raw materials are different in the previous granulation process, and the moisture content and hygroscopicity are also different. Therefore, during molding, bubbles, silver bars, poor transparency, cracks, poor stability and other problems are prone to occur, which seriously affect product quality. The air pipeline of the dehumidifying dryer adopts a closed circulation system, which can not be affected by the external weather. Whether it is dry weather or wet weather, the material can be dried well, without moisture, and the product molding quality is high.

The dehumidifying dryer first draws the air in the environment to remove the moisture in the air at a low dew point, and then heats the dried air into one or more standard drying hoppers, which can improve drying efficiency and shorten drying time. If the traditional hot air blower is used to dry the material with external air with moisture, it is difficult to achieve the drying effect. In addition, when the plastic is taken out of the moisture-proof sealed packaging bag and exposed to the air, it will start to absorb moisture from the air. The traditional hot air blower cannot prevent the plastic from continuously absorbing moisture, and the drying effect is poor.

The dehumidifying dryer is different from the drying method of the traditional hot air blower. It sends the heated air into one or more standard drying hoppers, which not only improves the drying efficiency and shortens the drying time, but also is not restricted by the environment, ensuring excellent quality. drying effect. However, due to the different physical properties of different raw materials, the required drying temperature is also different, and a reasonable drying temperature needs to be set according to the actual situation.

1. Definition of drying temperature of dehumidifying dryer

The drying temperature of the dehumidifying dryer refers to the temperature of the air entering the drying barrel. Due to the different physical properties of each raw material, such as molecular structure, specific gravity, moisture content and other factors, there is a certain limit on the drying temperature. When the temperature is too high, some additives in the raw materials will volatilize and deteriorate or agglomerate, and if the temperature is too low, some crystalline raw materials cannot meet the required drying conditions, and the drying effect is not good.

2. The drying temperature of the dehumidifying dryer

The drying time recommended by the supplier of the material to be dried by the desiccant dryer is 4 hours, and the processing capacity is 100 lb/h. To determine whether the airflow of the desiccant dryer is sufficient, you can measure the temperature curve in the drying silo. Here, pay special attention to the temperature at 4hr. If the temperature at the 400lb material level in the drying silo of the dehumidifying dryer reaches the set value, then the air flow can be considered sufficient (the dehumidifying dryer does not use raw materials). If only the material at 1hr, 2hr or 3hr in the drying silo is fully heated, it means that the air flow cannot complete the heating and drying of the material at the predetermined production rate.

If the material has not been properly dried after coming out of the desiccant dryer, it should be checked whether the drying silo has enough space to provide sufficient and effective drying time. The effective drying time of a desiccant dryer is the time the particles are actually exposed to the proper drying temperature and dew point. In addition, the return air temperature of the dryer should be checked frequently. When the return air temperature is high, it may indicate that the size of the dryer is too large for the production rate, or the temperature of the material entering the drying silo is too high. In order to prevent the return air temperature from becoming high, it is necessary to install a heat exchanger on the return air path, to ensure that the dryer can effectively remove the moisture in the dry air to ensure the drying effect.

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