No abstract

As new and efficient dehydration technology and equipment needs to be applied to the recycling of Chinese urban garbage urgently, this study discusses the differences and similarities between spiral-extrusion and screw-extrusion physical model on dehydration technology. Based on the research on screw-extrusion dehydration technology, the factors that affect dehydration production volume and efficiency of urban garbage’s recycling have been analyzed. Using screw-extrusion theoretical model, the paper further discusses the influence of some parameters such as operation factors, geometric structure and urban garbage’s material performance. Finally, experiment research is made to examine the screw-extrusion theoretical model. The results show that appropriate screw speed can balance the production volume and dehydration efficiency. The main factors of geometric parameters are screw diameter, screw groove depth and helix angle, and all of these three factors can influence dehydration output and efficiency.

As final component of coextrusion system in polymer industry to produce product with multi-layer different materials, the coextrusion-die can be regarded as the most important determinant that can influence product quality directly. For design of die-cave that can make uniform pressure and speed distribution for different materials, geometry structure of die-cave and rheology performances of materials must be taken into consideration. In order to reduce the influence of operation uncertainty of polymer extrusion, damping block can be used to make adjustment for flowing speed of different materials. In this paper, a finite element method based simulation is made to analyze the impact of the damping-block to the uniformity of coextrusion flowing. With the simulation result, control methods for coextrusion quality are discussed for damping-block design and operation condition settings.