Parneet Paul

Development and testing of a fully adaptable membrane bioreactor fouling model for a sidestream configuration system.

A dead-end filtration model that includes the three main fouling mechanisms mentioned in Hermia (i.e., cake build-up, complete pore blocking, and pore constriction) and that was based on a constant trans-membrane pressure (TMP) operation was extensively modified so it could be used for a sidestream configuration membrane bioreactor (MBR) situation. Modifications and add-ons to this basic model included: alteration so that it could be used for varying flux and varying TMP operations; inclusion of a backwash mode; it described pore constriction (i.e., irreversible fouling) in relation to the concentration of soluble microbial products (SMP) in the liquor; and, it could be used in a cross flow scenario by the addition of scouring terms in the model formulation. The additional terms in this modified model were checked against an already published model to see if they made sense, physically speaking. Next this modified model was calibrated and validated in Matlab© using data collected by carrying out flux stepping tests on both a pilot sidestream MBR plant, and then a pilot membrane filtration unit. The model fit proved good, especially for the pilot filtration unit data. In conclusion, this model formulation is of the right level of complexity to be used for most practical MBR situations.

Investigating the influence of geotextile layers as biofilm granular filters to treat stormwater

This study investigated the application of geotextiles as sustainable urban drainage systems for degradation of organic pollutant load present in stormwater. Three experimental granular filter rigs were used, packed with alternating layers made up of gravel, pea gravel, sand and either an upper layer, an upper and lower layer or no layer of geotextile. The hydraulic loading capacity matched that commonly used on conventional sand filters. Standard water quality parameters were measured and collated data was evaluated using an ANOVA and Levines test of homogeneity of variance procedure. It was found that the rig with both upper and lower geotextiles had a statistically significant difference in data from the rig with only a single geotextile layer. High chemical oxygen demand (58–80%) and suspended solids (88–99.99%) removal rates occurred for all rigs. However, the control rig showed increased outflow concentration of nutrients indicating the potential of geotextiles for stormwater treatment.

Obsolescence types and the built environment – definitions and implications

In view of the literature to date as well as anecdotal conversations with practitioners and consultants in various sectors of the built environment industry, it is observed that the term ‘obsolescence’ is scarcely used or comprehended with its diverse implications. In the context of climate change impacts this term is even more uncommon. This paper describes implications of the term in the form of definitions and types of obsolescence from various perspectives, including the built environment and climate change. This study also briefly explains that obsolescence is a multi-faceted entity and the comprehension of its concept and implications can help to effectively manage the built environment in a sustainable manner, particularly to the face of climate change. This paper can stimulate both debate as well as further research in industry and academe, respectively.

Comparing and Contrasting Traditional Membrane Bioreactor Models with Novel Ones Based on Time Series Analysis

The computer modelling and simulation of wastewater treatment plant and their specific technologies, such as membrane bioreactors (MBRs), are becoming increasingly useful to consultant engineers when designing, upgrading, retrofitting, operating and controlling these plant. This research uses traditional phenomenological mechanistic models based on MBR filtration and biochemical processes to measure the effectiveness of alternative and novel time series models based upon input–output system identification methods. Both model types are calibrated and validated using similar plant layouts and data sets derived for this purpose. Results prove that although both approaches have their advantages, they also have specific disadvantages as well. In conclusion, the MBR plant designer and/or operator who wishes to use good quality, calibrated models to gain a better understanding of their process, should carefully consider which model type is selected based upon on what their initial modelling objectives are. Each situation usually proves unique.

Sustainability of and Obsolescence in the Built Environment: Two Contrary Notions

The research described in this article introduces a new, but overlooked, insights about the inverse linkages between sustainability and obsolescence. This article explores the concepts, not only at an overall level via the individual definitions of the terms, but also on social, economic, and environmental grounds that are important to sustainability discussions. Comparisons between the two notions along these three dimensions are elaborated with illustrative examples and real-life case studies. A conceptual illustration is also presented on how the two concepts operate in opposition to each other over time. This article is intended to not only introduce innovative concepts, particularly in the context of the built environment, but also to provoke healthy debate and discussion among researchers and practitioners alike. Hopefully this debate will enhance these proposed innovative concepts as well as generate new ideas and approaches toward the sustainable management of the built environment.

Implementation of membrane bioreactor fouling models based on linear and bilinear autoregressive model structures

Abstract The focus of this research is to create pragmatic and novel membrane bioreactor (MBR) models which can be applied for plant design, control and optimisation. Consequently, this research compares the traditional mechanistic models based on existing well known MBR filtration and biochemical processes with alternatives forms based on autoregressive input–output model formulations that in turn are based on system identification methods. Both model types are calibrated and validated using the same plant layouts and datasets derived for this purpose. This collated plant information included data obtained from carrying out standard flux-stepping experiments on a membrane filtration unit, and long term filtration experiments on a pilot MBR plant. In order to overcome the inherent deficiencies in any traditional approach, a novel alternative approach was tried in order to predict membrane filtration and fouling process for a MBR in a quick and easy manner. The rationale behind this novel approach is that ...