Biofilm growth pattern in honeycomb monolith packings: Effect of shear rate and substrate transport limitations
Biofilm growth pattern in honeycomb monolith packings: Effect of shear rate and substrate transport limitations
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DOI：
10.1016/j.cattod.2005.06.051
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发表时间：
2005-08-15
期刊：
影响因子：
5.3
通讯作者：
van Loosdrecht, MCM
中科院分区：
文献类型：
--
作者：
Ebrahimi, S;Picioreanu, C;van Loosdrecht, MCM
对整体式反应器在生物过程中的潜在应用进行了实验研究。在生物应用中使用整体式反应器时，一个可能的问题是由于生物膜的形成而堵塞。一个有趣的现象是生物膜在整体通道内发展的模式。乍一看相当出人意料的是，人们反复观察到，生物膜的形成始于正方形整体通道一侧的中间，而不是首先定居在角落的低剪切区。为了解释这种生物膜形成模式，本研究建立了一个基于底物扩散和消耗以及微生物生长和脱落的二维机理模型。模拟结果表明，生物膜生长和生物膜脱落之间的平衡是由于剪应力引起的侵蚀而产生的意外生物膜图案。在早期阶段，角部的生物膜生长受到外部对底物转移的阻力的强烈限制。随着时间的推移和生物膜厚度的增加，通过气泡的机械力将导致更规则的生物膜形状，包括通道角落。(C)2005 Elsevier B.V.保留所有权利。
Potential application of monolith reactors in a biological process was investigated experimentally. A possible problem when using monolith reactors in biological applications is clogging due to biofilm formation. An interesting phenomenon is the pattern in which biofilms develop inside the monolith channels. Rather unexpectedly at a first glance, it was repeatedly observed that biofilm formation started in the middle of a side of the square-section monolith channels, instead of colonizing first the low-shear areas in the corners. To explain this biofilm formation pattern, a two-dimensional mechanistic model based on substrate diffusion and consumption accompanied by microbial growth and detachment was developed in this study. Simulation results suggest that the unexpected biofilm patterns are generated by the balance between biofilm growth and biofilm detachment due to shear stress induced erosion. In the early stages, the biofilm growth in the corners is strongly limited by the external resistance to subs trate transfer. As time passes and the biofilm grows in thickness, mechanical forces due to passing gas bubbles will lead to a more regular biofilm shape, including the channel corners. (c) 2005 Elsevier B.V. All rights reserved.