摘要
采用计算流体动力学和FLUENT软件模拟了循环曝气生物滤池中空气和水两相以不同的体积流量比接触时水中溶解氧的浓度分布和滤池内循环水的流动状况。模拟结果表明,随着qV(空气)∶qV(水)的增大,溶解氧在水中分布更加均匀,水中溶解氧的平均浓度也不断上升,但增速逐渐变小,当qV(空气)∶qV(水)>24∶1时变化已不明显;循环水的流速随着qV(空气)∶qV(水)的增大而上升,循环流量可以达到进水量的20倍以上;生物滤池填料层中水的流动状态为层流,曝气筒中水的流动状态为湍流,既有利于强化气液两相的传质,也有利于废水生物降解和提高系统抗冲击能力。
The distribution of dissolved oxygen and circular velocity of water in circulating biological aerated filter were simulated with computational fluid dynamics and FLUENT at different ratios of air to water flow rate.The results showed that the distribution of dissolved oxygen in water became more even and the mean concentration of dissolved oxygen rose constantly as the ratio of air to water flow rate increased but no more than 24∶1.Circular velocity of water rose as the ratio of air to water flow rate increased and circulation flux may reach more than twenty times of influent.The flow pattern in packing was laminar and that in aerated tubes was turbulent which was beneficial to mass transfer between gas and liquid phases and biodegradation of wastewater and to improve the reactor＇s system shock resistance.
出处
《化工科技》
CAS
2015年第4期9-14,共6页
Science & Technology in Chemical Industry
基金
广东省自然科学基金资助项目(91529021000005)
关键词
循环曝气生物滤池
数值模拟
计算流体动力学
Circulating biological aerated filter
Numerical simulation
Computational fluid dynamics
