气动乳化脱硫筒内气液两相流动的数值模拟

Numerical simulation of gas-liquid two-phase flow in a pneumatic emulsifying desulfurization cylinder

为直观地了解和分析脱硫筒内部气液两相的混合与流动规律,采用CFD仿真软件对某公司大型湿法脱硫塔内气动乳化脱硫筒内气液流动进行数值模拟,分析了加装湍流器、改变湍流器角度以及喷雾锥角对脱硫筒内气液两相流动混合的影响;选用可实现的k-ε湍流模型和DPM模型,结合SIMPLE算法对气、液两相进行数值模拟。模拟结果显示,增设湍流器与提高喷雾锥角能够有效提高气液两相紊动混合度,提高脱硫反应的传质效率。流场分布、气液混合与能量损失等的模拟结果表明:当湍流器角度为30°~36°时,加装湍流器的效果最佳;当喷雾锥角为120°~180°时,系统内喷淋液分布比较均匀,与烟气的混合比较充分,有利于脱硫反应的进行。以上研究结果可为大型电厂脱硫塔中气动乳化脱硫筒设备的设计制造与运行管理提供参考。

In order to directly understand and analyze the gas-liquid two-phase flow mixing characteristics in the desulfurization cylinder of a large-scale wet desulfurization tower in a company,CFD technique was introduced to simulate the flow field.In this study,the effects of adding turbulators,changing turbulator angle and spray cone angle on the mixing characteristics were analyzed.The realizable k-εmodel and DPM model,combined with SIMPLE algorithm were used to simulate the gas-liquid two-phase.The simulation results showed that adding turbulator and increasing spray cone angle could effectively improve the degree of gasliquid two-phase turbulence mixing,and enhance the mass transfer efficiency of desulfurization reaction.Taking into consideration of the distribution of the flow field,the mixing degree of gas-liquid and the loss of energy,the best performance of the turbulator angle was between 30°to 36°.When the spray cone angle was between 120°to 180°,the distribution of spray liquid in the system was relatively uniform and the mixture with flue gas was sufficient,which was conducive to the desulfurization reaction.The results of the research provide references for the design,manufacturing and operation of the pneumatic emulsifying desulfurization cylinder in the large power desulfurization tower.