Study On Optimum Condition Of Conventional Steam-Dehumidification Combined Drying Wood

With development of production, conflict of demand and supply of energy sources is increasing, tension of environment used energy in industry is on rise, so saving resources and protecting environment is of importance.Each of drying means is its disadvantages and its applied scope, while combined drying is able to avail themselves of advantages and to steer clear of their disadvantages and accords with innovation trend of international drying technology. Combined drying isn't simple combination of two drying means, but is optimizing match in allusion to different drying means.According to data, study and application on conventional steam-dehumidification drying have had in China, but optimum optimum condition of them is of absence. At the same time, as far as know, there is empty of all-around and systemic study on it overseas. Therefore, study on optimum condition of conventional steam-dehumidification combined drying is important actual sense.By figuring out consumption of every technics phases of conventional steam drying and dehumidification, and analysis of figures, it finds out optimum condition of conventional steam-dehumidification drying, it is that pre-heat is used by steam, that at evaporation phase, from initial moisture of wood to 24 percent of moisture, energy is recycled by dehumidification, that at rest of time, drying is used by conventional steam drying, and that under 24 percent of moisture, drying is used by conventional steam drying and moisture exhausts by vent.According as its condition it figures out the consumption of conventional steam-dehumidification drying and compares to consumption of three drying means. It makes it clear that the energy cost of dehumidification drying is the lest, but its period is the longest, and that the energy cost of conventional steam-dehumidification drying is less, but it is less than that of conventional steam drying by 17.6 percent, and comparing with the dehumidification drying's period, its period decreases by 55 percent. Therefore, the superiority of combined drying is showed, at the same time, the rationality of optimum condition appears.By testing consumption of every technics phases of conventional steam drying and dehumidification, and analysis of figures, it finds out optimum condition of conventional steam-dehumidification drying, it is that pre-heat is used by steam, that at evaporation phase, from initial moisture of wood to 23 percent of moisture, energy is recycled by dehumidification, that at rest of time, drying is used by conventional steam, and that under 23 percent of moisture, drying is used by conventional steam and moisture exhausts by vent.According as its condition it does test of conventional steam-dehumidification drying wood, and it compares and analyses three drying means. As is result that combined drying haves caloric loss of exhaust, but the caloric loss accounts for very little of overall supply energy, that combined drying compares with conventional steam drying, the caloric loss of combined drying is almost excepted, so combined drying economizes amount of energy, and that comparing with the dehumidification drying's period, its period decreases by half. Thus it can be seen that combined drying is superiority, and that rationality of optimum condition of conventional steam-dehumification drying wood is farther validated experimentally. It compares experimental optimum condition with theoretical optimum condition, both is consistent on the whole.The innovation of the thesis is to find out the optimum condition of conventional steam-dehumidification combined drying from the aspect of theory and experiment and the rationality of optimum condition is validated experimentally.