Wastewater Treatment with Particulate Biofilm Reactors
TL;DR: In this paper, a review of applications of particulate biofilm reactors (e.g., upflow sludge blanket, Biofilm Fluidized Bed, Expanded Granular Sludge Blanket, biofilm Airlift Suspension, Internal Circulation Reactor) is presented.
Abstract: The review presented in this paper focuses on applications of particulate biofilm reactors (e.g. Upflow Sludge Blanket, Biofilm Fluidized Bed, Expanded Granular Sludge Blanket, Biofilm Airlift Suspension, Internal Circulation reactors). Several full-scale applications for municipal and industrial wastewater treatment are presented and illustrated, and their most important design and operation aspects (e.g. biofilm formation, hydrodynamics, mass transfer, mixing) are analysed and discussed. It is clear from the review that this technology can be considered a grown up technology for which good design and scale-up guidelines are available.
Citations
More filters
TL;DR: A membrane bioreactor (MBR) based method for growing a highly enriched anammox microbial community and the intrinsic nitrite half saturation constant was identified to be as low as 35 μg-N L(-)(1).
362 citations
TL;DR: Aerobic granular sludge can successfully be cultivated in a sequencing batch reactor (SBR) treating dairy wastewater, and the maximum applicable loading rate is nevertheless limited, as the stability of aerobic granules very much depends on the presence of distinct feast and famine conditions.
Abstract: Aerobic granular sludge can successfully be cultivated in a sequencing batch reactor (SBR) treating dairy wastewater. Attention has to be paid to the fact that suspended solids are always present in the effluent of aerobic granular sludge reactors, making a post-treatment step necessary. Sufficient post-treatment can be achieved through a sedimentation process with a hydraulic retention time of 15–30 min. After complete granulation and the separation of biomass from the effluent, removal efficiencies of 90% CODtotal, 80% Ntotal and 67% Ptotal can be achieved at a volumetric exchange ratio of 50% and a cycle duration of 8 h. Effluent values stabilize at around 125 mg l−1 CODdissolved. The maximum applicable loading rate is nevertheless limited, as the stability of aerobic granules very much depends on the presence of distinct feast and famine conditions and the degradation of real wastewaters shows slower kinetics compared with synthetic wastewaters. As loading rate and volumetric exchange ratio are coupled in an SBR system, the potential of granular sludge for improving process efficiency is also limited.
230 citations
Cites background from "Wastewater Treatment with Particula..."
...Granular sludge can hence be considered an appropriate measure for realizing a high-rate aerobic treatment system and for enhancing the capacity of an existing system that is limited by its volumetric conversion capacities (Nicolella et al. 2000)....
[...]
TL;DR: This paper reviews the formation, structure, and stability of bioaggregates with an emphasis on the composition and distribution of extracellular polymeric substances (EPS) and their role in bioaggregation.
Abstract: This paper reviews the formation, structure, and stability of bioaggregates with an emphasis on the composition and distribution of extracellular polymeric substances (EPS) and their role in bioaggregation. Bioaggregation is ubiquitous in natural environment and is of great importance in biological wastewater treatment processes. It greatly influences the flocculability, settleability, and dewaterability for flocs and sludge retention and shear resistance for biofilms. The physico-chemical and microbial structures of bioaggregates are dependent on operational conditions as well as microbial diversity and spatial distribution. The formation of bioaggregates is mediated by the physico-chemical interactions as well as the microbial interactions such as EPS production and quorum sensing. EPS are composed of a mixture of macromolecules including proteins, polysaccharides, humic-like substances, and nucleic acids, which entrap the microbial cells in a three-dimensional matrix. The composition and physico-chemical characteristics of EPS have significant influence on the maintenance of the bioaggregate structure and the process performance of the wastewater treatment. However, the mechanisms of bioaggregation are still unclear and the conclusions on the role of EPS were mostly drawn from the established correlations and hypotheses. This paper expects to provide up-to-date knowledge on bioaggregation and insights for further studies and applications.
181 citations
Cites methods from "Wastewater Treatment with Particula..."
...To avoid confusion, the term biofilm includes granules and attached growth systems in this paper, which is in compliance with Nicolella et al. (2000) and Maksimova (2014)....
[...]
TL;DR: It is demonstrated that immotile cells, including those identical to the biofilm resident strain, are completely excluded from entry into resident biofilms, using the model bacterium Vibrio cholerae as a model.
Abstract: Many bacteria are highly adapted for life in communities, or biofilms. A defining feature of biofilms is the production of extracellular matrix that binds cells together. The biofilm matrix provides numerous fitness benefits, including protection from environmental stresses and enhanced nutrient availability. Here we investigate defense against biofilm invasion using the model bacterium Vibrio cholerae. We demonstrate that immotile cells, including those identical to the biofilm resident strain, are completely excluded from entry into resident biofilms. Motile cells can colonize and grow on the biofilm exterior, but are readily removed by shear forces. Protection from invasion into the biofilm interior is mediated by the secreted protein RbmA, which binds mother-daughter cell pairs to each other and to polysaccharide components of the matrix. RbmA, and the invasion protection it confers, strongly localize to the cell lineages that produce it.
178 citations
Cites background from "Wastewater Treatment with Particula..."
...The strain composition and spatial arrangement of bacteria in biofilm communities strongly influence the course of bacterial infections, the functioning of our resident microbiota, bacterial contributions to biogeochemical cycling and industrial bioremediation (Nicolella et al., 2000; Costerton, 2001; Oggioni et al., 2006; Arnosti, 2011; von Rosenvinge et al., 2013)....
[...]
...…communities strongly influence the course of bacterial infections, the functioning of our resident microbiota, bacterial contributions to biogeochemical cycling and industrial bioremediation (Nicolella et al., 2000; Costerton, 2001; Oggioni et al., 2006; Arnosti, 2011; von Rosenvinge et al., 2013)....
[...]
TL;DR: In this review, a comparative analysis of various technologies is summarized with their working principle, advantages, and limitations followed by special focus on biosorption.
171 citations
References
More filters
TL;DR: It is clear from the review that particulate biofilm reactors can be considered a grown up technology for which good design and scale-up guidelines are available.
440 citations