[ Processus de Récupération et de valorisation du Phosphore à partir d'échantillons d'eaux de la station de traitement des eaux usées de la ville de Settat ]
Volume 18, Issue 3, November 2016, Pages 721–731
Asmaa KARBOUBI1, Abdeljalil ZOUHRI2, and Abdellah ANOUAR3
1 Laboratoire de chimie appliquée et environnement, Faculté des Sciences et Techniques, Université Hassan 1er Km 3, 5 route de Casablanca, BP 577 Settat, Morocco
2 Laboratoire de chimie appliquée et environnement, Faculté des Sciences et Techniques, Université Hassan 1er Km 3, 5 route de Casablanca, BP 577 Settat, Morocco
3 Laboratoire de chimie appliquée et environnement, Faculté des Sciences et Techniques, Université Hassan 1er Km 3, 5 route de Casablanca, BP 577 Settat, Morocco
Original language: French
Copyright © 2016 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The focus in recent years has been on process improvements that lead to enhanced recovery of phosphorus from wastewater. This study was designed to develop a methodology based on the operating results of numerical simulations and laboratory experiments. The developed methodology is meant to determine the conditions favoring the maximum efficiency for the recovery of calcium phosphates. It concerns the modeling of chemical equilibria, for calculating the rate of conversion of phosphate depending on the pH and the reactant concentration of the developed reaction and their dependence on supersaturation. To measure the phosphate conversion rate, experiments were carried out in aqueous solution at different pH (from 9.5 to 11.5) for molar ratios of initial ion concentrations of Ca / P in different temperature (25 ° C). These conditions were chosen to cover the pH values at which calcium phosphate crystallizes easily. In order to achieve a visible precipitate and phosphorus removal efficiency close to 90%, 2 hours contact time was also required. The precipitation / crystallization process was then studied using the VISUAL MINTEQ program as a predictive tool to determine the conditions that affect the saturation index as a dependent function of the pH and the concentration of calcium, revealing the existence of three different stages.
Author Keywords: crystallization, simulation, supersaturation, initial molar ratio Ca / P, conversion ratio.
Volume 18, Issue 3, November 2016, Pages 721–731
Asmaa KARBOUBI1, Abdeljalil ZOUHRI2, and Abdellah ANOUAR3
1 Laboratoire de chimie appliquée et environnement, Faculté des Sciences et Techniques, Université Hassan 1er Km 3, 5 route de Casablanca, BP 577 Settat, Morocco
2 Laboratoire de chimie appliquée et environnement, Faculté des Sciences et Techniques, Université Hassan 1er Km 3, 5 route de Casablanca, BP 577 Settat, Morocco
3 Laboratoire de chimie appliquée et environnement, Faculté des Sciences et Techniques, Université Hassan 1er Km 3, 5 route de Casablanca, BP 577 Settat, Morocco
Original language: French
Copyright © 2016 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
The focus in recent years has been on process improvements that lead to enhanced recovery of phosphorus from wastewater. This study was designed to develop a methodology based on the operating results of numerical simulations and laboratory experiments. The developed methodology is meant to determine the conditions favoring the maximum efficiency for the recovery of calcium phosphates. It concerns the modeling of chemical equilibria, for calculating the rate of conversion of phosphate depending on the pH and the reactant concentration of the developed reaction and their dependence on supersaturation. To measure the phosphate conversion rate, experiments were carried out in aqueous solution at different pH (from 9.5 to 11.5) for molar ratios of initial ion concentrations of Ca / P in different temperature (25 ° C). These conditions were chosen to cover the pH values at which calcium phosphate crystallizes easily. In order to achieve a visible precipitate and phosphorus removal efficiency close to 90%, 2 hours contact time was also required. The precipitation / crystallization process was then studied using the VISUAL MINTEQ program as a predictive tool to determine the conditions that affect the saturation index as a dependent function of the pH and the concentration of calcium, revealing the existence of three different stages.
Author Keywords: crystallization, simulation, supersaturation, initial molar ratio Ca / P, conversion ratio.
Abstract: (french)
L'accent au cours des dernières années a été axé sur l'amélioration des processus qui conduisent à la récupération assistée du phosphore des eaux usées. Le présent travail a été conçu pour développer une méthodologie fondée sur l’exploitation de résultats de simulations numériques et d’expérimentations en laboratoire. La méthodologie développée permet de déterminer les conditions favorisant l’efficacité maximale pour la récupération des phosphates de calcium. Elle concerne la modélisation des équilibres chimiques, pour calculer le taux de conversion du phosphate en fonction du pH et la concentration des réactifs de la réaction développée et leur dépendance à la sursaturation. Pour mesurer le taux de conversion des phosphates, des expériences ont été effectuées en solution aqueuse à différents pH (de 9,5 à 11,5) pour des rapports molaires de concentrations ioniques initiales Ca/P différentes à température (25 ° C). Ces conditions ont été choisies pour couvrir les valeurs de pH à laquelle le phosphate de calcium cristallise facilement. Afin d'atteindre un précipité visible et une efficacité d'élimination du phosphore près de 90%, 2 heures de temps de contact ont été également requises. Le processus de précipitation /cristallisation a ensuite été étudié en utilisant le programme VISUAL MINTEQ comme un outil de prédiction pour déterminer les conditions qui influent sur l’indice de saturation en tant que fonction dépendant du pH et de la concentration de calcium, révélant ainsi l'existence de trois stades différents.
Author Keywords: cristallisation, simulation, sursaturation, rapport molaire initial Ca / P, taux de conversion.
How to Cite this Article
Asmaa KARBOUBI, Abdeljalil ZOUHRI, and Abdellah ANOUAR, “Phosphorus recovery and enhancement process from water samples of the wastewater treatment plant of the city of Settat,” International Journal of Innovation and Applied Studies, vol. 18, no. 3, pp. 721–731, November 2016.
