Working principle and characteristics of DW series belt dryer

DW series belt dryer is a common continuous drying equipment, which can be widely used in chemical industry, food, medicine, building materials, electronics and other industries It is suitable for drying flaky, strip and granular materials with good air permeability, especially for materials with high moisture content such as dehydrated vegetables, Chinese herbal pieces and other materials whose temperature is not allowed to be high DW series belt dryer has the advantages of fast drying speed, high evaporation intensity and good product quality For the paste materials of dehydrated filter cake, it can also be dried after forming by pelletizer or extrusion mechanism The principle and characteristics are as follows: the materials in the hopper of DW series belt dryer are evenly laid on the mesh belt by the feeder, the mesh belt is made of 12-60 mesh stainless steel wire mesh, which is dragged in the dryer by the transmission device The drying section is composed of several units, each of which has its own hot air circulation Part of the tail gas is discharged by a special exhaust fan, and the exhaust gas volume of each unit is controlled by a regulating valve In the upper circulating unit, the air from the circulating fan enters the lower chamber of the unit from the side air duct, and the air flow is heated up through the heat exchanger and distributed by the distributor The jet stream blows to the mesh belt, passes through the material and enters the upper chamber The drying process is a process in which hot air flows through the material layer to convey heat and quality The upper chamber is connected with the inlet of the fan by the air duct Most of the gas and fluid circulates Some of the gas with lower temperature and larger moisture content is discharged as the waste gas through the dehumidification pipe, regulating valve and jump wet fan In the lower circulating unit, the air from the circulating fan enters the upper chamber first, then it is heated by the heat exchanger downward and enters the lower chamber through the material layer The lower chamber is connected with the fan inlet by the side air duct and return air pipe Most of the air circulates and some is discharged The upper and lower circulation units can be flexibly equipped according to the needs of users, and the number of units can also be selected according to the needs If DW series belt dryer is used for dehydrating vegetables, three sets of equipment are generally used in series to form the initial, intermediate and final drying sections In the primary drying section, due to the high moisture content and poor air permeability of the material, small laying thickness, fast operation speed and high drying temperature are adopted If the temperature of the material is not allowed to exceed 60 ℃, the temperature of the drying gas in the initial drying section can be controlled below 120 ℃; the retention time of the material in the final drying section is 3-6 times of that in the initial drying section, and the thickness of the paving material is 2-4 times of that in the initial drying section For the requirement that the material temperature is not more than 60 ℃, a dry gas of about 80 ℃ can be used The performance of DW series belt dryer can be better developed by adopting multi-stage combination, and the drying is more uniform.