Time filter

Source Type

Lancaster, United Kingdom

Bieroza M.,Center for Sustainable Water Management | Baker A.,University of New South Wales | Bridgeman J.,University of Birmingham
Journal of Environmental Engineering | Year: 2011

Optimization of organic matter (OM) removal is of key importance for effective water treatment, as its presence affects treatment processes. In particular, OM increases the operational cost of treatment caused by increased coagulant and disinfectant demands. In the work reported here, fluorescence spectroscopy is used to assess the effect of changing coagulation pH on OM removal, character, and composition. The results of a 3-month trial of low pH coagulation operation at a major surface water treatment works in the Midlands region of the UK are discussed, together with the effect upon total organic carbon (TOC) removal. OM removal was assessed on the basis of both measured removal and fluorescence-inferred removal (through intensity-reduction measurements). Fluorescence spectroscopy demonstrated that optimized coagulation affects the quantitative and qualitative OM properties. Fluorescence analyses were shown to complement other OM measurements, with reductions of peak intensities correlating well with removal of TOC in a range of different treatment conditions. © 2011 American Society of Civil Engineers. Source

Bieroza M.,Center for Sustainable Water Management | Baker A.,University of New South Wales | Bridgeman J.,University of Birmingham
Education for Chemical Engineers | Year: 2012

Large datasets are common in chemical and environmental engineering applications and tools for their analysis are in great demand. Here, the outputs of a series of fluorescence spectroscopy analyses are utilised to demonstrate the application of the self-organising map (SOM) technique for data analysis. Fluorescence spectroscopy is a well-established technique of organic matter fingerprinting in water. The technique can provide detailed information on the physico-chemical properties of water. However, analysis of fluorescence spectra requires the application of robust statistical and computational data pre-processing and analysis tools.This paper presents a tutorial for training engineering postgraduate researchers in the use of SOM techniques using MATLAB®. Via a tutorial, the application of SOM to fluorescence spectra and, in particular, the characterisation of organic matter removal in water treatment, is presented. The tutorial presents a step-by-step example of the application of SOM to fluorescence data analysis and includes the source code for MATLAB®, together with presentation and discussion of the results. With this tutorial we hope to popularise this robust pattern recognition technique for fluorescence data analysis and large data sets in general, and also to provide educational practitioners with a novel tool with which to train engineering students in SOM. © 2011 The Institution of Chemical Engineers. Source

Bieroza M.,Center for Sustainable Water Management | Baker A.,University of New South Wales | Bridgeman J.,University of Birmingham
Advances in Engineering Software | Year: 2012

For the first time, the application of different robust data mining techniques to the assessment of water treatment performance is considered. Principal components analysis (PCA), parallel factor analysis (PARAFAC), and a self-organizing map (SOM) were used in the analysis of multivariate data characterising organic matter (OM) removal at 16 water treatment works. Decomposed fluorescence data from PCA, PARAFAC and SOM were used as input to calibrate fluorescence data with OM concentrations using stepwise regression (SR), partial least squares (PLS), multiple linear regression (MLR), and neural network with back-propagation algorithm (BPNN). The best results were obtained with combined PARAFAC/PLS and SOM/BPNN. Both the numerical accuracy and feasibility of the adopted solutions were compared and recommendations on the use of the above techniques for fluorescence data analysis are presented. © 2011 Civil-Comp Ltd and Elsevier Ltd. All rights reserved. Source

Riley M.S.,University of Birmingham | Tellam J.H.,University of Birmingham | Greswell R.B.,University of Birmingham | Durand V.,University of Birmingham | And 3 more authors.
Water Resources Research | Year: 2011

A mathematical model describing the steady state flows in a forced gradient tracer test between an injection and pumping borehole in a multilayered sandstone aquifer has been developed that includes the effect of vertically variable background heads. A second model describing the recovery of tracer from a layer in which there are discharges due to vertical flow in the injection borehole is also presented. Application of the models to field tracer test data indicates that the observed recoveries, which are not proportional to the abstraction rate in each layer, are consistent with the hydraulic behavior of the aquifer when natural vertical head gradients are taken into account. Investigation with the models illustrates that the vertical distribution of tracer recovery depends strongly upon the background heads and that tracer tests conducted in the same aquifer, but at different times, may interrogate different aquifer layers. It is also shown generally that for a given abstraction rate the vertical distribution of tracer recovery in small-scale tracer tests is controlled largely by the transmissivity distribution but that as the spatial scale of the test increases, the distribution of recovery becomes proportional to the discharges from the injection borehole because of vertical flows within it, which may be natural or induced by pumping in the monitoring borehole. Uncertainties inherent in the design of forced gradient tracer tests in multilayered aquifers and the problems of applying the results of such tests to natural gradient contaminant migration are discussed. Copyright 2011 by the American Geophysical Union. Source

Bieroza M.,Center for Sustainable Water Management | Baker A.,University of New South Wales | Bridgeman J.,University of Birmingham | Boomer I.,University of Birmingham
Proceedings of the Institution of Civil Engineers: Water Management | Year: 2014

To date, the δ18O and δ2H stable isotopic composition of freshwaters has received little attention compared to stable isotopes in precipitation. Specifically, studies characterising the stable isotopic variability of surface waters on regional and local scales are limited. Here, the δ18O and δ2H stable isotopic compositions of raw and partially treated waters from 16 UK water treatment works are examined. The water treatment works abstract surface waters from a range of catchments (upland versus lowland and semi-natural versus anthropogenically impacted). The investigation of stable isotope composition and deuterium excess (d-excess) revealed a high degree of spatial and temporal variability. Compared to rainfall, the spatial and temporal variability of surface water is more complex and catchment-dependent. Multiple linear regression analysis identified moderately strong relationships between catchment controls (altitude, mean rainfall, base flow index, aquifer permeability, location) and δ2H, δ18O and d-excess of raw and partially treated waters. Results suggest that catchment controls explain 60% (δ2H), 66% (δ18O) and 74% (d-excess) of the variation in isotopic composition of raw water. Results also indicate that catchment permeability has a stronger influence on surface waters isotopic composition than altitude, latitude or rainfall effects. The potential benefits from the use of isotopic composition data in the water supply are discussed. © 2015, Thomas Telford Services Ltd. Source

Discover hidden collaborations