Assessing filter robustness at drinking water treatment plants

Abstract

This investigation explores the use of five‐parameter logistic curve fitting in quantifying turbidity robustness and risk scoring in clarification and filtrations stages of several surface water treatment works in the Anglian Water region of the United Kingdom. The approach taken reviews different scoring systems and addresses issues of weighting, averages and variability in robustness performance using turbidity robustness indices (TRIs). It also proposes an area‐based risk scoring profile to assess performance [relative area profile for T90 (RAP90)]. The metrics produced are considered to be a logical and rational way to help prioritise where resources for water treatment operation should be deployed.

Performance of Four Full-Scale Artificially Aerated Horizontal Flow Constructed Wetlands for Domestic Wastewater Treatment

“…In this context, robustness is described as the ability of a treatment unit to produce consistent effluent quality under varying influent characteristics and differentiates from resilience, which is defined as the ability to return to normal after a dynamic event [19]. Resilience was assessed by evaluating the response of Site B to an upstream process failure and time to restore nitrification capacity in Site A after a period of 5 months where the beds were taken offline.…”

“…A robustness index (RI) was calculated with respect to overall ammonium removal performance against a treatment goal (T goal ) and the percentage time spent under the treatment goal (Equation (1), [19]). As the goal term heavily influences the outcome, RI was calculated for a range of treatment goals from 0.1 to 5 mgNH 4 + -N/L.…”

“…A lower robustness score indicates a more robust process. In accordance with Reference [19], the approach was used to assess overall robustness rather than directly assess the ability of the sites to meet regulatory standards as RI is more effectively used as an indicator of variation rather than directly about meeting a fixed goal. Accordingly the 90th percentile was used to avoid confusion with regulatory compliance at the 95th percentile.…”

Control of desalination plants using sliding mode scheme with state observer

“…Hence, RO systems often operate under many parametric uncertainties and exogenous disturbances that can cause deterioration of system performance in some plant operational stages, if they are controlled by conventional controllers in the RO literature. On the other hand, due to global climate change, the operational condition for desalination plants is getting harsher and harsher (Hartshorn et al 2015). Despite the recent improvement in designing membranes and filters (Bhatti et al 2020;Fazelabdolabadi & Golestan 2020;Hussain & Al-Fatlawi 2020), a modern RO plant still requires a more efficient control system to offer its optimal operation against severe working conditions.…”

Evaluación de la turbiedad como parámetro indicador del tratamiento en una planta potabilizadora municipal

“…Esto exige métodos complementarios para su tratamiento [2]. La eficiencia de una planta de tratamiento de agua potable está ligada al cumplimiento de la legislación en la calidad de agua suministrada sin importar los cambios en la calidad del agua del afluente [3]. Es así, como la turbidez se ha posicionado como un parámetro fisicoquímico importante para medir la calidad de agua en las fuentes de abastecimiento y en el agua suministrada a los usuarios [4] La turbidez refleja el contenido de sustancias coloidales, minerales u orgánicas en el agua, por lo que puede ser indicio de contaminación [5].…”