摘要
[目的]分析填料粒径对生物滞留池(BRC)渗透性能及微生物膜形态的作用机理,以期优选出适合生物滞留池填料层的颗粒粒径及相应填充的孔隙率。[方法]采用数值模拟和试验实测相结合的方法,利用Fluent软件对BRC小尺度计算区域范围内的流场形态进行模拟,对6种粒径(0.5,1.0,2.0,4.0,6.0,8.0 mm)下的流线图、压力分布及变化图进行综合对比分析。为验证模拟结果的正确性,对不同颗粒粒径进行生物膜培养和运行,测定颗粒表面生物膜厚度。[结果]平均粒径为0.5~1.0 mm时流场形态最好,可形成结构合理数量较多的小涡流,有利于水流渗透及物质传递的进行,实测生物膜也表明粒径为1.0 mm时,微生物膜生长最为均匀且生物量最大。[结论]填料的粒径会影响BRC的运行效果,数值模拟可为实际粒径的选取提供参考。
[Objective]The effect mechanism of packing particle sizes on the permeability of bioretention cells(BRC)and biofilm patterns was analyzed in order to optimize the particle size and corresponding filling porosity of the BRC packing layer.[Methods]By numerical simulation and experimental measurement methods,fluent software was employed to simulate and analyze the flow field pattern of BRC in the small-scale calculation zone.The streamline diagram,pressure distribution,and change diagram for six different sizes of granule particles(0.5,1.0,2.0,4.0,6.0,and 8.0 mm)were comprehensively compared.In order to verify the correctness of the simulation results,biofilms with different particle sizes were cultured and operated.The thickness of the biofilm on the particle surface was measured.[Results]When the average particle sizes were 0.5—1.0 mm,the flow field pattern was the best and a smaller eddy current with reasonable structure could be formed.This flow field was the most conducive to water infiltration and material transfer.The measured thickness of the biofilm also showed that when the particle size was 1.0 mm,the growth of the biofilm was the most uniform and the biomass was the largest.[Conclusion]The packing particle size will affect the operation effects of the BRC,and the numerical simulation can provide a reference selection of actual particle sizes in the BRC.
作者
王进喜
王亚军
周玉青
Wang Jinxi;Wang Yajun;Zhou Yuqin(School of Chemical Engineering,Lanzhou University of Arts and Science,Lanzhou,Gansu 730000,China;School of Civil Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050,China)
出处
《水土保持通报》
CSCD
北大核心
2020年第5期134-140,共7页
Bulletin of Soil and Water Conservation
基金
甘肃省陇原青年创新创业人才项目(2020RCXM205)
国家自然科学基金项目“生物滞留系统对城市污水厂尾水中典型抗生素的去除及其强化机制”(41967043)
兰州文理学院2020年度省级“大学生创新创业训练计划”项目(S202011562033)。
关键词
生物滞留池
小尺度流场模拟
试验验证
生物膜形态
bioretention cells
flow field simulation
experimental verification
biofilm morphological structure