20 research outputs found
A Survey of Deep Learning Methods for WTP Control and Monitoring
Drinking water is vital for everyday life. We are dependent on water for everything from cooking to sanitation. Without water, it is estimated that the average, healthy human won’t live more than 3–5 days. The water is therefore essential for the productivity of our community. The water treatment process (WTP) may vary slightly at different locations, depending on the technology of the plant and the water it needs to process, but the basic principles are largely the same. As the WTP is complex, traditional laboratory methods and mathematical models have limitations to optimize this type of operations. These pose challenges for water-sanitation services and research community. To overcome this matter, deep learning is used as an alternative to provide various solutions in WTP optimization. Compared to traditional machine learning methods and because of its practicability, deep learning has a strong learning ability to better use data sets for data mining and knowledge extraction. The aim of this survey is to review the existing advanced approaches of deep learning and their applications in WTP especially in coagulation control and monitoring. Besides, we also discuss the limitations and prospects of deep learning
Gestion supervisée d’une unité de coagulation pour la potabilisation des eaux à partir d’une méthodologie d’apprentissage et d’expertise
Le travail présenté propose une méthodologie de classification par apprentissage qui permet l’identification des états fonctionnels sur une unité de coagulation impliquée dans le traitement des eaux de surface. La supervision et le diagnostic de ce procédé ont été réalisés en utilisant la méthode de classification LAMDA (Learning Algorithm for Multivariate Data Analysis). Cette méthodologie d’apprentissage et d’expertise permet d’exploiter et d’agréger toutes les informations provenant du procédé et de son environnement ainsi que les connaissances de l’expert. L’étude montre qu’il est possible d’ajouter aux informations issues des capteurs classiques (température, matières en suspension, pH, conductivité, oxygène dissous), la valeur de la dose de coagulant calculée par un capteur logiciel développé dans une étude antérieure afin d’affiner le diagnostic. Le site d’application choisi pour l’identification des états fonctionnels est la station de production d’eau potable Rocade de la ville de Marrakech, Maroc.The present work proposes a learning classification method to identify the functional states of a coagulation process for the treatment of surface water and production of drinking water. Supervisory control and diagnosis were performed using the LAMDA (Learning Algorithm for Multivariate Data Analysis) classification technique. This expert learning method involves the processing and aggregation of all information stemming from an environmental process, and it allows the incorporation of the user’s knowledge. The study shows that it is possible to refine the diagnosis by taking into account the information obtained from common sensors (e.g., temperature, suspended solids, pH, conductivity, dissolved oxygen) together with the predicted coagulant dosage, as computed with an intelligent software sensor developed previously. The Rocade drinking water plant located at Marrakech, Morocco was chosen to test the method
Numerical Investigation to Quantify the Rate of Damage within Mortar Bituminous Materials: Modeling of Cracks Initiation and Propagation
Asphalt concrete is highly used to construct pavement layers in the civil engineering field. It is defined as a complex medium composed of aggregates (inclusions), mortar (matrix) and air void. The mortar itself is a mixture of fillers, sand and bitumen. Furthermore, mortar is the phase that links the coarse aggregates. In general, fracture of asphalt concrete occurs within mortar or among aggregate-mortar interface. Therefore, two types of fracture can be identified, i.e., adhesive and cohesive damages. The first type is occurred among the interface of aggregate-mortar. The second is taken place within the mortar. This paper presents numerical investigations of the damage initiation and stiffness degradation within the asphalt concrete matrix. Numerical simulations were carried out to investigate, firstly, how damage is initiated and developed, and then, to simulate how cracks can be initiated and propagated within this material. Cohesive finite elements method was adopted to simulate fracture. For adhesive damage, the model was represented by one rectangular aggregate that is linked to the asphalt concrete thanks to a thin layer of the mortar. For cohesive damage, the model was considered as a thick layer of the mortar in between two coarse aggregates. The applied loading was derived from the speed of traffic vehicle. A comparative analysis between four mortars was conducted. The effect of loading and the type of mortar on damage initiation and stiffness degradation will be shown. Moreover, the initiation and propagation of cracks as function of loading and stiffness modulus will be illustrated
Detection of functional states by the ‘LAMDA’ classification technique: application to a coagulation process in drinking water treatment
Approximate Analytical Solution for One-Dimensional Solidification Problem of a Finite Superheating Phase Change Material Including the Effects of Wall and Thermal Contact Resistances
This work reports an analytical solution for the solidification of a superheating phase change material (PCM) contained in a rectangular enclosure with a finite height. The analytical solution has been obtained by solving nondimensional energy equations by using the perturbation method for a small perturbation parameter: the Stefan number, ε. This analytical solution, which takes into account the effects of the superheating of PCM, finite height of the enclosure, thickness of the wall, and wall-solid shell interfacial thermal resistances, was expressed in terms of nondimensional temperature distributions of the bottom wall of the enclosure and both PCM phases, and the dimensionless solid-liquid interface position and its dimensionless speed. The developed solution was firstly compared with that existing in the literature for the case of nonsuperheating PCM. The predicted results agreed well with those published in the literature. Next, a parametric study was carried out in order to study the impacts of the dimensionless control parameters on the dimensionless temperature distributions of the wall, the solid shell, and liquid phase of the PCM, as well as the solid-liquid interface position and its dimensionless speed
Thermodynamic Analysis and Mathematic Modeling of Waste Sludge from Drinking Water Treatment Plants
Water treatment annually produces a huge amount of Drinking Water Treatment Sludge (DWTS) wastes. The latter causes environmental problems in Morocco in terms of energy and pollution. Therefore, cost-effective and eco-friendly solutions for managing them should be proposed in order to reduce the frequency of storage along with transportation costs. In this paper, a thermodynamic analysis of DWTS wastes was conducted based on the isosteric heat and compensation theory. Different results concerning the mineralogical identification of sludges were established. Findings revealed that the by-product of water purification was mainly composed of aluminum, silica and iron hydroxides, with pH varying between 6.23 and 6.85. The suspended matter was between 18.3 and 19.6 m/l. The volatile matter of the three sludge samples was between 18 and 21%. The measured dry matter content was between 13.41 and 15.23%. The experimental tests were performed under temperatures from 45 and 60 °C, the experimental data of the sorption curves were fitted by using several models of correlation. Furthermore, the analysis showed that the Peleg’s model perfectly described the isotherm curves in the activities ranging from 0 to 90%. The net isosteric heats of sorption of the three hydroxide sludge from the Moroccan treatment station: , and , were determined for desorption and adsorption. Moreover, it was revealed that the equilibrium water content rising lead contributed to the reduction of the net isosteric heat and the entropy of sorption. Finally, the enthalpy-entropy compensation showed that the sorption mechanism involved was enthalpy driven
Vers l'élaboration d'un système d'aide à la décision pour le choix des méthodes d'estimation des débits max des crues : réadaptation aux données hydrologiques récentes
Le Maroc de part sa situation géographique connait beaucoup d'épisodes de crues, qui se sont amplifiées ces dernières décennies à cause des effets de changements climatiques, induisant beaucoup de dégâts humains et matériels. Ainsi le but du présent travail est la réadaptation des méthodes d'estimation des débits max des crues utilisés pour le dimensionnement des ouvrages hydrauliques à la lumière des nouvelles données hydro pluviométriques extrêmes observées. Cela en vue de la création d'un Système d'Aide à la Décision (SAD) pouvant aider les ingénieurs à choisir la méthode d'estimation des débits max des crues la mieux adaptée selon l'ouvrage hydraulique à dimensionner et les données disponibles.
L'article décrit la méthodologie de réadaptation des méthodes sur l'exemple du bassin de Tensift.
Il s'agit en premier lieu de caractériser le bassin et de calculer ses paramètres structurels et morphologiques. La deuxième étape est l'identification des groupes homogènes avec un comportement climatique similaire pour lesquels un même modèle d'estimation des crues peut être utilisé. Ainsi l'analyse en composantes principales sur les précipitations mensuelles a permis de retenir quatre groupes homogènes.
La troisième étape consiste à fiabiliser et régionaliser les méthodes usuelles d'estimation des débits max des crues à savoir les méthodes statistiques et hydrométéorologiques, dont la méthode du Gradex et méthodes empiriques.
Un schéma d'un système d'aide à la décision (SAD), sous forme d'une plateforme informatique est proposé
Couplage des procédés membranaires aux techniques physico-chimiques ou biologiques pour le traitement des rejets liquides de l'industrie de textile
Le traitement des rejets textiles se fait habituellement via une filière physico-chimique couplée à un traitement biologique. La qualité de l effluent obtenu obéit difficilement aux normes de recyclage ou de rejet dans le milieu naturel. Dans cet objectif, différentes combinaisons sont proposées: la coagulation floculation (CF) et/ou l adsorption sur charbon actif (CAP) en poudre couplée aux techniques membranaires (microfiltration (MF) ou ultrafiltration (UF)), la photocatalyse couplée à un traitement aérobie biologique (système membranaire (BRM) ou réacteur discontinu séquentiel (RDS)) ou au traitement anaérobie par voie biologique ou chimique. Une comparaison générale a été réalisée pour optimiser le traitement adéquat. La combinaison CF-CAP-UF est un traitement efficace pour la réduction de la DCO, de la couleur et de la turbidité. La dégradation de deux colorants textiles (azoïque et phthalocyanine) a été étudiée par photocatalyse simple ou combinée à un BRM. Le traitement photocatalytique a été réalisé en présence de dioxyde de titane fixé sur un support en fibres de cellulose dans un réacteur à film tombant en présence d irradiation UV. Pour les deux types de réacteurs biologiques, bien que la biomasse ait été influencée par la variation de la concentration en colorant et par le mode de fonctionnement continu pour le BRM, elle a pu résister. Après le pré-traitement nous avons obtenu une complète décoloration mais les sous produits photocatalytiques demeurent toxiques et peuvent empêcher l abattement de la DCO. Dans une dernière partie, nous avons testé le couplage de la photocatalyse à un traitement chimique par hydrogénation catalytique ou biologique par boues granulaires. Cette dernière possibilité s avère être efficace puisque des taux de décoloration supérieurs à 90% ont été atteints pour différents types de colorants et qu aucune toxicité des produits obtenus lors du pré-traitement photocatalytique n a été détectéeThe treatment of textile wastewater is usually done by a set of physicochemical processes coupled with a biological treatment. The effluent quality abides with difficulty the norms for reuse or discharge in environment. Various treatment combinations have been tested such as coagulation-flocculation (CF) and adsorption on activated carbon (PAC) coupled with membrane technologies (microfiltration (MF) or ultrafiltration (UF)), photocatalysis coupled with a biological treatment (membrane bioreactor (MBR) or a sequential batch reactor (SBR) or a biological and chemical anaerobic treatment. A general comparison was made to optimise the appropriate treatment. The combination CF-PAC-UF is the most effective of non-biological systems in terms of COD, absorbance and turbidity removal. The degradation of an azoïc and a phthalocyanine textile dyes by simple photocatalysis or combined to a membrane bioreactor has been investigated. Photocatalysis was achieved in a falling film reactor containing titanium dioxide fixed on cellulose fibres under UV irradiation. For both biological systems, although biomass was influenced by the variation of dyes concentration and the continuous operating mode for the MBR, it could resist to the applied conditions. However, even after pre-treatment where full decolouration was achieved, photocatalytic by-products were toxic and could inhibit COD removal. Chemical and biological anaerobic treatment have been applied to textile dyes and combined with a photocatalytic process. Photocatalysis was able to remove more than 90% color from crude as well as autoxidized reduced dye solutions. The photocatalytic end-products were not toxic toward methanogenic bacteriaNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF