Experimental Research On Gas-liquid Hydrocyclone With Improved Structure

Factors affecting separation performance of gas-liquid cyclone mainly included short-circuit, secondary vortex, back-mixing and entrainment of outlet. Based on classic DN75gas cyclone structure, annulus was introduced outside the overflow tube. The optimal annulus structure was confirmed by investigating the separation performance change under various operating parameters. Through setting anti-backmixing cone in the centre of outlet, the effect of cone angle0or pass-flow area rate S on separation performance was examined. In order to address cooling tower plume problem, a5t/h cooling tower was built with internal installed of straight-flow or tangential-flow cyclone, the effect of additional cyclones to the performance of cooling, de-mist and water-saving was also studied. The main conclusions are as follows:(1) After setting annulus at vortex, the cyclone pressure drop ΔP reduced. And the pressure drop would decrease further with the increasing value of annulus. A new pressure loss coefficient ε is introduced to describe the effects of annulus on pressure drop. The maximum ratio of bypass flow is between3%~6%, which is less than the value of10%-20%of common hydraulic cyclone. Considering the two factors of separation efficiency and pressure drop, the author believe2.5mm is the best value of annulus. The separation efficiency could be82.3%when the flow rate was60m3/h. Considering the water evaporation influence, and the final fixed efficiency value could up to91.2%by excluding the influence of water evaporation.(2) After setting anti-backmixing cone in the centre of outlet, the cyclone separation efficiency is improved, but the pressure drop is also increased. When the cone angle is90°and pass-flow area rate is30%, the optimal separation performance was obtained. The fixed efficiency could up to86.4%when the flow rate was60m3/h.(3) After installing the built-in tangential flow cyclones, air flow rate reduced by turbine due to the high pressure drop of cyclone, which made the cooling performance affected. Since the flow of single cyclone is only30m3/h, which isn’t is not the optimal process flow, the recovery of water mist in the exhaust gas is only about50%. Given the advantages such as low pressure drop and high throughput, the installation of built-in straight flow cyclone would improve the cooling performanceunder the same operating coditions, while the recovery of water mist in the exhaust gaswas only between25%~35%...