What are the factors that affect the drying effect of spray dryer?

What are the factors that affect the drying effect of spray dryer? Choose different nebulizer for different materials, so that the finished products with good effect can be dried Low temperature spray dryer often spray atomizing dryer In fact, atomization of spray dryer is related to product moisture, particle size and sticky wall Different atomization methods are different according to different products Many users are confronted with problems such as uneven water content, uneven particle size, and conglomerate sticking of equipment tower or cone when using spray dryer It is related to the moisture, particle size and wall adhesion of the product The dryer is to vaporize and escape the moisture in the material (generally referring to moisture or other volatile liquid components) by heating, so as to obtain the solid material with specified moisture content The purpose of drying is to meet the needs of material use or further processing In fact, drying is a relatively simple process, but in some cases, the particles can not be completely dried The reason for this is that some external factors affect the drying effect, specifically in the following aspects: 1 Drying temperature: refers to the temperature of the air entering the drying barrel Due to the physical properties of each raw material, such as molecular structure, specific gravity, specific heat, moisture content and other factors, there are certain restrictions on the temperature during drying When the temperature is too high, the local additives in the raw material will volatilize, deteriorate or agglomerate, and when it is too low, some crystalline raw materials will not reach the required drying conditions, such as PC / 120 ℃ , ABS / 80 to 95 ℃ In addition, in dry barrel selection, insulation insulation and low temperature spray dryer are needed to avoid drying temperature leakage, resulting in lack of drying temperature or waste of energy 2 Dew point: in the dryer, first remove the wet air to make it contain very low residual moisture (dew point) Then, reduce the relative humidity of the air by heating it At this time, the steam pressure of dry air is low By heating, the water molecules inside the particles get rid of the binding force and diffuse to the air around the particles 3 Time: in the air around the particles, the absorption of heat and the diffusion of water molecules to the particle surface need a certain time Therefore, the resin supplier shall specify the time required for an effective drying of a material at an appropriate temperature and dew point 4 Air flow: the dry hot air will transfer the heat to the particles in the drying silo, remove the moisture on the particle surface, and then send the moisture back to the dryer Therefore, there must be enough air flow to heat the resin to the drying temperature, and maintain this temperature for a certain period of time 5 Air volume: the air volume takes away the Wei medium of moisture in raw materials The air volume will affect the dehumidification effect If the air volume is too large, the return air temperature will be too high, which will cause overheating and affect its stability If the air volume is too small, the moisture in the raw material cannot be completely removed The air volume also represents the dehumidification capacity of the dehumidification dryer.