Search results for "reactors"

A dynamic air–liquid interface system for in vitro mimicking of the nasal mucosa

2022

The development of an in vitro 3D model for the growth of the nasal mucosa cells can improve the therapy and the study of pathological states for subjects with chronic airway conditions. We have previously characterized a system consisting of a scaffold with an internal channel and a perfusion bioreactor with two independent flows provided by an external and an internal circuit, respectively. In this paper, this system was designed as a model of the nasal cavity, in which cells, grown on the inner surface of the scaffold channel, would be in contact at the same time with both culture medium, supplied by the external circuit, and air, provided with the internal flow. To ensure adequate nutri…

Widening the applicability of AnMBR for urban wastewater treatment through PDMS membranes for dissolved methane capture: Effect of temperature and hy…

2021

[EN] AnMBR technology is a promising alternative to achieve future energy-efficiency and environmental-friendly urban wastewater (UWW) treatment. However, the large amount of dissolved methane lost in the effluent represents a potential high environmental impact that hinder the feasibility of this technology for full-scale applications. The use of degassing membranes (DM) to capture the dissolved methane from AnMBR effluents can be considered as an interesting alternative to solve this problem although further research is required to assess the suitability of this emerging technology. The aim of this study was to assess the effect of operating temperature and hydrodynamics on the capture of…

DEVELOPMENT OF ELECTROCHEMICAL MICROFLUIC DEVICES FOR THE TREATMENT OF WASTEWATERS AND THE SYNTHESIS OF CHEMICAL

Photocatalytic ozonation under visible light for the remediation of water effluents and its integration with an electro-membrane bioreactor

2018

Abstract Photocatalysis and photocatalytic ozonation under visible light have been applied for the purification of a complex aqueous matrix such as the grey water of Masdar City (UAE), by using N-doped brookite-rutile catalysts. Preliminary runs on 4-nitrophenol (4-NP) solutions allowed to test the reaction system in the presence of a model pollutant and to afford the relevant kinetic parameters of the process. Subsequently, the remediation of grey water effluent has been evaluated in terms of the reduction of total organic carbon (TOC) and bacterial counts. The concentration of the most abundant inorganic ionic species in the effluent has been also monitored during reaction. Photocatalytic…

ELECTROCHEMICAL MICROREACTORS FOR THE ABATEMENT OF ORGANIC POLLUTANTS IN WATER SOLUTION

2015

Electrochemical methods can offer new sustainable routes for the abatement of organic pollutants resistant to biological processes. These methods use a clean reagent, the electron, and very mild operative conditions (ambient temperature and atmospheric pressure) with limited operative costs. However, electrochemical processes present some important disadvantages when performed in conventional reactors. In particular, to achieve reasonable cell voltages when the medium has not an adequate conductivity, one needs adding to the system a supporting electrolyte. This is certainly a main obstacle for a wide application of electrochemical tools. Indeed, adding chemicals is often a problematic issu…

Hybrid moving bed biofilm reactors: an effective solution for upgrading a large wastewater treatment plant

2009

Over the last few years there has been a growing attention regarding the receiving water body quality state. As a matter of a fact, the Directive 91/271 of the European Union (EU) replaced the “emission standard” concept that fixes discharge limits depending on polluting emission characteristics, with the “stream standard” concept that fixes discharge limits for each polluting substance depending on self-depurative characteristics of the RWB. In this context, several WWTPs need to be upgraded in order to meet stricter effluent limits. The need of WWTP upgrading was also emphasized by the growing urbanization that have led, in most cases, to get overloaded WWTP due to an overcoming of the ma…

Hybrid moving bed biofilm reactors: a pilot plant experiment.

2008

The growing increment of the urbanization and on the other hand, the even more strict effluent limits imposed by the Water Framework Directive for the receiving water body quality state have lead to a need of upgrading several existing WWTP. With this respect HMBBR systems are an innovative solution since allow to upgrade existing high loaded WWTP without building new tanks. However, some uncertainties in their design, maintenance as well as performance have to be addressed due to their recent acquisition compared with well consolidated technologies such as activated sludge systems. In this light, a data gathering campaign on a HMBBR pilot plant has been performed. The aim was to detect the…

Modelling of hybrid moving bed biofilm reactors: a pilot plant experiment.

2007

In recent years there has been an increasing interest in the development of hybrid biofilm reactors, especially in the upgrading of existing WWTP that are no longer able to respect concentration limits. In fact, today's challenge is the achievement of a good aquatic state for the receiving water bodies according to the Water Framework Directive requirements, which indeed limit even more the continuous emissions, i.e. coming from WWTP. This paper presents the setting up of a mathematical model for the simulation of a hybrid MBBR system; the model calibration/validation has been carried out considering a field gathering campaign on an experimental pilot plant. The main goal is to gain insight…

Parameter subset selection for the dynamic calibration of activated sludge models (ASMs): experience versus systems analysis.

2007

In this work we address the issue of parameter subset selection within the scope of activated sludge model calibration. To this end, we evaluate two approaches: (i) systems analysis and (ii) experience-based approach. The evaluation has been carried out using a dynamic model (ASM2d) calibrated to describe nitrogen and phosphorus removal in the Haaren WWTP (The Netherlands). The parameter significance ranking shows that the temperature correction coefficients are among the most influential parameters on the model output. This outcome confronts the previous identifiability studies and the experience based approaches which excluded them from their analysis. Systems analysis reveals that parame…

Instrumentation, control, and automation for submerged anaerobic membrane bioreactors

2015

A submerged anaerobic membrane bioreactor (AnMBR) demonstration plant with two commercial hollow-fibre ultrafiltration systems (PURON® , Koch Membrane Systems, PUR-PSH31) was designed and operated for urban wastewater treatment. An instrumentation, control, and automation (ICA) system was designed and implemented for proper process performance. Several single-input-single-output (SISO) feedback control loops based on conventional on off and PID algorithms were implemented to control the following operating variables: flow-rates (influent, permeate, sludge recycling and wasting, and recycled biogas through both reactor and membrane tanks), sludge wasting volume, temperature, transmembrane pr…