Analysis of the Influence of Vortexbinder Dimension on Cyclone Separator Performance in Biomass Gasification System

Producer gas produced from biomass gasification still contains particulate ash. It is cleaned by using a cyclone separator. Cyclone separator capability to 'capture' ash is characterized by its performance known as collection efficiency. One major factor influencing cyclone separator performance is vortex finder dimension. A cyclone separator model with 2D standard configuration with 150 mm diameter has beenmade. Standard configuration model isused to minimize geometrical factors affecting cyclone separator performance other than vortex finder itself. Three variations of length (3/8 D; 5/8 D; 1 D) and three variations of diameter (35; 70; 85 mm) of vortex finder are used to identify their influences on cyclone performance. Experimental study and CFD simulation using ANSYS Fluent were performed. Experimental study aims to find out vortex finder dimension effects on collection efficiency trend, whileCFD simulation goal is to determine the velocity profile of air inside cyclone separator. RNG k-ɛ for swirl dominated flow was chosen as the turbulence model. Velocity magnitude inside cyclone separator is used to predict the collection efficiency trend. Collection efficiency fromexperimentare determined by weighing method, i.e. percentage of total mass of ash captured divided by total mass of ash entering cyclone separator. Experimental results show that increasing vortex finder length and decreasing vortex finder diameter can increase the collection efficiency. In general, increasing vortex finder length and decreasing vortex finder diameter can also increasethe velocity magnitude of air inside cyclone separator. Highest collection efficiency is achieved by using vortex finder with 35 mm (1/4 D) in diameter and 1 D (150 mm) in length.