| With the rapid development of the global economy, which the demand of energy is increasing, especially the non-renewable energy demand that accounted for a significant proportion, this thesis is based on the current global situation for a study. Our country is a property rich big country, at the same time, is also a big country which has rich in forest resources and agricultural products. A large number of solar energy are stored in these trees and crops straw, after burning can be made a great of the heat, is a renewable-biomass energy that is able to live instead of coal and oil. However, combustion energy obtained directly from this biomass is limited, and they are inconvenient storage and transportation. Therefore, we need to pretreatment the source of biomass and pressed into granules and then combusted.Based on the related literature of dryer at home and abroad, according to actual needs of drying biomass, the drying process of biomass were studied, determined the suitable drying methods, designed a spin-jet dryer that meet the requirements of modern drying technology, has important practical significance in effective utilization of energy. The main research contents of this article were as follows:(1) This paper introduced the principle of the traditional drying, aiming at the shortcomings of the traditional drying, we put forward the new spin-jet dryer design concept. Described the new process of new spin-jet dryer, designed the main body of spin-jet dryer, including the size calculation of Venturi tube, the shell size determination of dryer, the design of the air flow control valve, etc, and accessory equipment selection.(2) According to the energy conservation equation and heat-mass transferring theory knowledge, summary energy equations of the spin-jet dryer, expressed thermal efficiency of and dry strength of the spin-jet dryer, introduced the characteristics of limited space of jet and rotary jet, and their relationships with the spin-jet dryer.(3) The FLUENT CFD software is used for single-phase gas analysis of spin-jet drier, including analysis of gas flow field, analysis of temperature changes and analysis of pressure distribution. It is proved to verify whether the designed dryer can achieve the desired results and calculation results is consistent. (4) Determined the needed factors for the experiment by using the orthogonal experiment method, including the inlet air temperature, air flow rate, feed speed and the size of the classifier, controlling these factors, and then results were measured and recorded through the experiment of measuring instruments under the influence of different factors, the corresponding conclusions were received.This study shows that the design of this new type spin-jet dryer was reasonable, the primary and secondary relations of the various influence factors of drying effects were obtained through the experiments, which the temperature of the air flow was one of the largest factor influenced on the drying effect. |
