Energy consumption in terms of shear stress for two types of membrane bioreactors used for municipal wastewater treatment processes

Archives of Thermodynamics

Nicolas RatkovichCorresponding authorDepartment of Civil Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, DenmarkEmailOther articles by this author:De Gruyter OnlineGoogle Scholar¹  Thomas R. BentzenDepartment of Civil Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, DenmarkOther articles by this author:De Gruyter OnlineGoogle Scholar¹  Michael R. RasmussenDepartment of Civil Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, DenmarkOther articles by this author:De Gruyter OnlineGoogle Scholar¹ 

[1] Department of Civil Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark

关键词: Keywords:: Shear stress;    Bubble column;    CFD;    Membrane bioreactor (MBR);   

DOI  :  10.2478/v10173-012-0012-1

学科分类：能源（综合）

来源: Polska Akademia Nauk * Oddzial w Gdansku, Instytut Maszyn Przeplywowych / Polish Academy of Sciences, Institute of Fluid-Flow Machinery

【 摘 要 】

Two types of submerged membrane bioreactors (MBR): hollow fiber (HF) and hollow sheet (HS), have been studied and compared in terms of energy consumption and average shear stress over the membrane wall. The analysis of energy consumption was made using the correlation to determine the blower power and the blower power demand per unit of permeate volume. Results showed that for the system geometries considered, in terms the of the blower power, the HF MBR requires less power compared to HS MBR. However, in terms of blower power per unit of permeate volume, the HS MBR requires less energy. The analysis of shear stress over the membrane surface was made using computational fluid dynamics (CFD) modelling. Experimental measurements for the HF MBR were compared with the CFD model and an error less that 8% was obtained. For the HS MBR, experimental measurements of velocity profiles were made and an error of 11% was found. This work uses an empirical relationship to determine the shear stress based on the ratio of aeration blower power to tank volume. This relationship is used in bubble column reactors and it is extrapolate to determine shear stress on MBR systems. This relationship proved to be overestimated by 28% compared to experimental measurements and CFD results. Therefore, a corrective factor is included in the relationship in order to account for the membrane placed inside the bioreactor.

【 授权许可】

Unknown