Study On The Collapse Recovery Technology And Mechanism Of Poplar Plantation

In order to further proven recovery mechanism and recovery power of wood collapse,, and to provide theoretical basis for the study of effective recovery collapse, and to provide technical support for efficient utilization of plantation timber. This paper mainly study on the poplar plantation in Inner Mongolia, and the recovery characteristics and mechanism of collapsed wood. And study on the control factors and recovery technology. To evaluate the collapse recovery effect by Using advanced digital image analysis method from the point of view of microscopic. The change of water status and crystallinity were compared before and after recovery.Main conclusions are summarized as follows:By poplar collapse recovery process optimization test, the recovery Ratio of tangential direction of Populus Xbeijingensis W. Y. Hsu.is19.83%, and the recovery Ratio of radial direction is9.12%. The recovery Ratio of tangential direction of100℃is26.68%,and the recovery Ratio of radial direction is9.36%. The recovery Ratio of tangential direction of6h is21.27%, and the recovery Ratio of radial direction is8.13%. the collpae parameters optimization results is100℃for the processing temperature, and6hfor the processing time.Obtained by poplar collpase recovery performance test, the maximum height of collpae is1.53mm of Populus X beijingensis W. Y. Hsu. the collapse factor is up to56.07of Populus X canadensis Moench, the maximum volume shrinkage is3.95%of Populus simonii Cam. After12h treatment, the minimum height of collapse reduced0.20mm. After6h treatment, the collapse factor is reduced to a minimum of23.79. The Sample s’ volume shrinkage ratio gradually increased along with the increase of processing time.By studying the different positions collapse recovery performance test, the height of collapse and volume shrinkage ratio of bottom is bigger In the vertical position, the height of collapse of Heartwood and sapwood border is larger, and the collapse factor of Heartwood is larger, and the volume shrinkage ratio of sapwood is bigger.From ultra-microscopic image analysis experiments shows that the collapse occurs the main area of the junction of the heart wood and sapwood of poplar plantation. After steam treatment, the recovery ratio is32.90%compared with before treatment by wood cell area increases significantly. The recovery ratio of Perimeter is20.65%. The most obvious recovery effect is in the junction of the heart wood and sapwood. As length direction, the degree of shrinkage did not show significantly.It is thin cylinder model about the collapse recovery cell model. The collapse recovery mechanism of wood:the cell walls absorb water and heat undergoes steam or saturated air treatment, the collapse cells began to recover when the rigid of cell wall reduced under drying stress. And the cell cavity further recoved shape by increasing of cell cavity pressure, because of thermal expansion of the air inside the cavity cells.