China Drying Network News Traditional tobacco baking, coal-fired barns occupy the largest market share, tobacco farmers and tobacco companies to accept such barns are also high. The main control parameters of such barn controllers are dry bulb temperature and wet bulb temperature in the barn. The control of the dry bulb temperature is mainly reflected in the heat source. The heat source needs to continuously provide the heat required for the dehumidification of the barn and the heat loss of the barn. At the same time, according to the requirements of the flue-cured tobacco technology, the heat source needs to maintain the maximum dry-bulb temperature of the baking room at 68°C during the color fixing stage of the tobacco leaves. Wet bulb temperature mainly adopts fresh air dehumidification method, utilizes the negative pressure formed by the circulating fan in the baking room, controls the opening of the new air damper, and controls the amount of fresh air entering the baking room, so as to control the indoor wet-bulb temperature. In the three stages of the drying and drying process , the maximum amount of moisture removal is the fixing stage. At this time, a large amount of cold wind enters the barn, and a large number of high-temperature, high-humidity and hot winds are directly discharged. The heat source needs to generate enough heat, and the barnhouse keeps the dry bulb temperature of the process required by 55-58°C. News link: Tobacco drying equipment Drying technology is widely used in tobacco processing, such as the redrying of raw tobacco and stems, baking of burley tobacco, and drying of leaf silk. The purpose and requirements of dry tobacco are different. Some of them are used to remove excess water for processing and storage; others are to increase their filling capacity and flammability; and others are used to improve and improve their sensory quality. For a long time, tobacco drying research has been highly valued by tobacco workers at home and abroad. The research progress of tobacco thermophysical properties The thermophysical data of tobacco is one of the basic data necessary for the design of tobacco machinery and the development of the processing conditions of cigarettes. The commonly used thermophysical property data in tobacco include specific heat capacity, enthalpy, entropy, thermal conductivity, thermal diffusivity, and adsorption heat and desorption heat of water in tobacco. As early as the 1950s, Brock and Samfield systematically measured the specific heat capacities of various tobaccos at different moisture contents, the desorption heat of water in tobacco, and the entropy change at the time of desorption, as well as the thermal diffusivity and heat conduction of various tobaccos. Rate, obtained a relatively complete tobacco thermal properties data and tobacco thermal properties and moisture content of the basic relationship: the specific heat capacity of tobacco, thermal conductivity with its increase in the moisture content increases; when the tobacco leaf moisture content is less than 20%, the tobacco heat diffusion The rate gradually decreases with the increase of tobacco moisture content; when the moisture content of tobacco leaves is 20% to 25%, the thermal diffusivity is the lowest, and when the moisture content of tobacco leaves exceeds 25%, the thermal diffusivity increases slightly with the increase of the moisture content. Grab Crane,Portable Crane ,Portable Gantry ,Over Head Cranes Overhead Crane Co., Ltd. , http://www.nbcraneseries.com
