Simulation And Experimental Research Of Injector Suction Performance For Compound Flotation Agitation Device

Based on the organic combination of three kinds of fluid characteristics about injection, vortex and agitation which having a large influence on flotation, this article puts forward a new type of flotation agitation device:compound flotation agitation device, by analyzing structure characteristics of mechanical agitation flotation machine and jet flotation machine. The working principle of compound flotation agitation device is certain pressure slurry through the self-priming ejector to suck the air, the ejector shoot out high-speed slurry to impact the impeller, thus driving the impeller to achieve the action of slurry agitation and bubble cutting. Aeration amount is an important indicator to evaluate the performance of flotation machine. The active principle of compound flotation agitation device is complex, it’s both ensure to suck enough air and ensure that the jet with sufficient impact to drive the impeller stirring. So, study the suction way and the suction performance in some suction way is an important aspect of the development of compound flotation agitation device, it has reference significance for the future research.This article use flow field simulation software to simulate injector structural characteristics, looking for the structural parameters of injector with optimal suction performance. Then injector physical model is manufactured and a series of experimental study are done. Ultimately, the feasibility of injector is determined and providing theoretical basis for compound flotation agitation device. The results showed that:1) For center air-inlet and surrounding-feed injector, the location of suction pipe in the injector has a great influence to suction performance. Suction pipe moves from the cone to the cylinder, suction amount increases quickly, it reaches the maximum value when the suction pipe in the joint between the cone and the cylindrical of injector. The suction amount gradually decreased with the movement of suction pipe in the cylindrical part.It has a good performance when the length of cylinder is8～16mm.it will be advantageous for the injector when shrinking angle α=15°.2)For center-feed and surrounding air-inlet injector, distance between water nozzle and mixed spout has a major influence on suction performance. Too big or too small distance both have influence on the suction performance of the ejector. when the distance is15mm, injector has a best suction performance.When the injector has best optimal distance, length of mixed spout has little influence on suction performance. There is a best mixed spout diameter make the best suction performance.3)For submerged jet, shrinking angle have a certain influence on the axial velocity of jet region, the axial velocity is best when α=15°.with the increase of angle, the axial velocity has a downward trend. The length of cylindrical section has little influence on axial velocity.4) Experiment research on two kinds of injector suggests that compared with the simulation results, experimental results are lower, but the trend of experiment results is similar to the simulation results. It proves the feasibility of the design of injector, and there is great possible to optimize in specific aspect.