Application scope of convective heat transfer drying equipment

Nanjing Tianli Pharmaceutical Equipment Co., Ltd is located in the beautiful eastern suburb of Nanjing, the ancient capital of Six Dynasties With an area of 26000m2 and a plant area of 10000m2, the company is a large-scale enterprise that produces pharmaceutical equipment, chemical equipment and food equipment in Nanjing (hot air circulation oven, vacuum drying oven, Vacuum oven); its brand products include: DMH series dry heat sterilization oven (Class 100, class 10000); zth series rubber plug sterilization (Class 100, class 10000) rotary oven; HDB, HDA (Class 100, class 10000) tunnel sterilization oven; ZDF / YZG series high, medium and low temperature vacuum oven; SZG series double cone rotary vacuum dryer; CT-C series hot air circulation oven; DW series belt dryer; LPG series Spray dryer; HG series of large electric heating blower dryer; FB type explosion-proof oven; CY type low temperature ozone sterilization oven; ZLG type vibratory fluidized bed dryer; BG type coating machine; CBX type ultrasonic bottle washing machine; CSQ type ultrasonic rubber plug cleaner; ZJP rotary drum rubber plug cleaner; XG type washing machine; VH type mixer; SYH type three dimensional motion mixer; VH type 2D motion mixer; The products are sold all over the country and abroad Eastern Europe The application of convective heat transfer drying equipment in the existing drying equipment, Zui is more convective heat transfer drying Such as hot air drying, hot air and dried materials contact for heat exchange to evaporate water The typical equipment of convection dryer is air suspension dryer, such as fluidized bed dryer, flash dryer, air dryer, spray dryer, ventilation dryer, flow dryer, air rotary dryer, stirring dryer, parallel flow dryer, rotary dryer, etc In practical application, there are single machine, combined machine and deformation machine The air dryer, fluidized bed dryer, spray dryer and so on all use hot air as the heat carrier, while drying, and also complete the transfer of materials This kind of dryer is characterized by no driving parts To dry powder, granule and flake materials, the common way of Zui is to heat air or gas flow on the surface of granule Through the air flow of the material for heat transfer, so that water evaporation The evaporated water vapor is taken away directly into the air The commonly used drying media in the drying system are air, inert gas, direct combustion gas or superheated steam The method makes the hot air directly contact with the material and removes the moisture while heating The key is to improve the contact area between materials and hot air and prevent hot air from deflecting The material temperature during constant speed drying is almost the same as the wet bulb temperature of hot air, so high temperature hot air can also be used to dry heat sensitive materials This drying method has high drying rate, less equipment investment, but low thermal efficiency The following is the basic situation of various convection drying equipment (1) the box dryer is one of the old driers of Zui The materials are packed in plates, which are placed on the unwheeling car layer by layer and placed in rows Steam or electricity are used as the heat source The hot air in the box can be recycled and partially discharged to make the drying more uniform Although the thermal efficiency is low, it is still being used in a large number and manufacturing continues The reason is that the structure is simple and the operation is not often taken care of and there is no obvious problem However, many materials need to be turned over and turned over when they are dry Heat sensitive materials are often discolored, and they are not suitable for drying materials with solvents Due to the accumulation of materials, the heat and mass transfer in the inner layer is poor, so the drying rate is low (2) tunnel drying room is designed to place the material tray on a special trolley, which can be used to enter and exit the tunnel one by one, so as to increase the output and thermal efficiency Other structures are similar to box dryers (3) the mesh belt dryer can be used to dry corn, grains, vegetables, etc This machine is equipped with a transmission belt made of stainless steel wire mesh The material moves with the belt and can be heated in sections The unit length of the device is 1.8-2m, Zui length can be connected to 40m, and the processing capacity per hour can be as high as 4T In the constant rate drying stage, the temperature of hot air can reach 130 ℃ and the relative humidity of exhaust gas can reach 85% (4) the multi-layer turbine dryer is a vertical cylinder, which is equipped with several layers of turntables The materials can be added from the top and discharged from the bottom layer by layer Hot air is introduced from the bottom and circulates air in sections by several blower turbine impellers located in the center of the cylinder Heaters are set at the corresponding height of the inner wall of the device to supplement the heat of the air and improve the thermal efficiency and drying rate However, the equipment is not easy to clean, and it is difficult for many kinds of production and clean materials