Effects Of Water Content On Flue Gas And Chemical Composition Of Flue Gas

Tobacco and tobacco products can offer sensory satisfaction by the components resulted from the burning tobacco. The combustion of tobacco and tobacco products is an extremely complicated physical and chemical reaction process, and the chemical compositions of cigarette smoke which have an effect on the sensory quality directly. All compounds which participant in the combustion process will have an effect on the combustibility of tobacco and tobacco products. But the physical properties of cigarette, for example, the equilibrium moisture content will also have an effect on the combustion process. Therefore the humectant was used to control the equilibrium moisture content during the production of cigarette to improve the combustion of cigarette, to improve the sensory quality of cigarettes. This thesis discusses the influence of the equilibrium moisture content and humectant content in tobacco on the physical and chemical properties of tobacco products, therefor on the combustion of cigarette.(1) The influence of the equilibrium moisture content on tobacco① The equilibrium moisture content in tobacco have an effect on the surface microstructure of tobacco. The result showed that the micro-structure of surface and fracture in tobacco are recovered with the increased equilibrium moisture content of tobacco.② The equilibrium moisture content in tobacco have effects on the factors of combustion characteristic, kinetics parameters and the chemical compositions of cigarette smoke. The combustibility of tobacco is reducing by the increased equilibrium moisture content of tobacco. The calculation models are different for each thermal weight loss stage of tobacco pyrolysis and combustion reaction. The thermal weight loss stage of tobacco pyrolysis reaction use F1, F2 mechanism models respectively to calculate the kinetics parameters, and the thermal weight loss stage of tobacco combustion reaction use F1, R3 mechanism models. Overall consideration by the combustibility, chemical compositions and content of tobacco, when the equilibrium moisture content of tobacco is 13.01%, the tobacco sample can keep combustibility better, and it resulted in preferring aroma and flavor of smoke.(2) The influence of the humectant content on tobacco① Sprinkling different content of 1,2-propanediol and glycerol on the tobacco followed by normal casing and flavoring and the moisture retention ability of tobacco was investigated by a dynamic vapour sorption (DVS) system, then the content of tobacco and mainstream smoke are measured. The result showed that the content of glycerol on the tobacco, which is measured, has a varying gradient, in addition, the humectant content of tobacco has a very small part removing to mainstream smoke, the content mobility of 1,2-propanediol is 3.57%～5.05%, the content mobility of glycerol is 5.44%～8.71%. Furthermore the more the content of humectant in tobacco, the higher the equilibrium moisture content of tobacco is higher. And it showed that the humectant is good to enhance humectant performance of tobacco.② The humectant content of tobacco has effects on the chemical compositions of cigarette smoke. Overall consideration by the chemical compositions and content of tobacco, when the content of 1,2-propanediol and glycerol are 0.1% and 1% on the tobacco which is the best. This sample can keep better combustibility and has a better aroma and flavor of tobacco.③ Comparison of four marketed cigarettes④ The humectant content of cigarette products of four brands was compared for each other. The results showed that the brand A has a higher humectant content, and the other three brands all have the content of 1,2-propanediol and glycerol between 0% to 0.1%, then the spraying content has a changing trend by the varying price categories.② The chemical compositions of cigarette smoke of four brands are equal nearly. The aroma components content of brand A has a changing trend by the varying price categories. However the aroma components content of brands B, C, D have no regular changes by the varying price categories. In addition the total content of phenolics showed a changing trend by the varying price categories of cigarette.