Study On Pyrolysis Characteristics And Kinetics Of The Typical Forest Fuel In Mao’er Mountain

Pyrolysis characteristics and kinetics of12herbaceous,8kinds of shrubs and8kinds of trees species grown in MaoEr of heilongjiang province area were studied by the thermogravimetric analysis. The analysis of TG-DTG curve of these fuels revealed their pyrolysis processes and pyrolysis parameters of quantitative comparison reflect the different plant fuel pyrolysis characteristics,and their activation energy and frequency factor were obtained by grading reaction kinetics model (Coats—Redfern method).:The results show that all the pyrolysis process of the samples in air atmosphere can be divided into four stages generally:dehydration stage, holocellulose pyrolysis stage, lignin pyrolysis stage, charring stage. Holocellulose pyrolysis stage and lignin pyrolysis stage are the two main weightlessness stages, Weight loss is more than80%of the initial weight, under low temperature pyrolysis reaction was more complex, it was connected with Benzyl ethanol extraction content decomposition. Several tree Species fuels in the late combustible600～650℃test made a small range of weightlessness, and it relates to itself chemical composition.With the pyrolysis characteristic parameters comparison, it was observed that the combustibility of Aquilegia vulgaris and Paeonia lactiflora were the best of twelve herb fuels, because of lower initial decomposition temperature, flame combustion intense, volatile matter more and the small ash content. Reversely the combustibility of Brachybotrys paridiformis and Rhizoma cimicifugae were the worst.Because their all the pyrolysis indexes were at middle level or lowest, flame burning not acuteness and more ash content. To shrubs fuels, the pyrolysis indexes of Leapedeza bicolor and Euonymus phellomana were at highest level, they were good inflammable and poor thermal stability. Reversely the pyrolysis indexes of Rhamnus ussuriensis were at middle or lowest level, it was an stronger fire-resistance in eight shrubs fuels. To tree fuels, the fire-resistance of Acer tegmentosum was the best, and recommended as fire resistance species for fire-preventing forest belts. The combustibility of Tilia amurensis was better of other seven tree species. Tree leaves was higher combustion than bark,Because of leaves have more benzyl ethanol extraction content and crude fat content.By the size of integral activation energy determining to the degree of difficulty of the pyrolysis reaction. Herb fuels combustion ease from high to low order was Parasenecio hastata> Filipendula palmata> Prenanthes tatarinowii> Paeonia lactiflora> Aquilegia vulgaris> Artemisia stolonifera> Eriophorum vaginatum> Adiantum pedatum> Pseudostellaria davidii>Brachybotrys paridiformis>Athyrium multidentatum>Rhizoma cimicifugae. The degree of difficulty of the pyrolysis of eight shrubs fuels was Euonymus alatus>Rhamnus ussuriensis>Aralia elata>Euonymus phellomana>Actinidia kolomikta> Leapedeza bicolor> Ribes diacanthum> Schisandra chinensis; tree species was Acer tegmentosum> Tilia mandschurica> Fraxinus mandshurica> Prunus maackii> Ulmus laciniata>Pouplus davidiana>Tilia amurensis>Quercus mongolica...