Hansen A.M.,Mexican Institute for Water Technology |
Gonzalez-Marquez L.C.,Mexican Institute for Water Technology
Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering | Year: 2010
The city of Guadalajara, Jalisco, Mexico has 4.1 million inhabitants and a serious deficit in water supply. Once constructed, the Arcediano Dam will catch waters from the Verde and Santiago rivers, and after treatment will provide water to the city. The present study was undertaken to formulate scenarios and estimate risks of polluting the water that will be collected in the dam from the release of contaminants accumulated in sediments. Desorption of metals from sediments was estimated through sampling of water and sediments, chemical analyses of the environmental samples, and numerical modeling of the water-sediment interactions. Water quality generally increased as the river flowed downstream from the El Salto sampling station to the site where the Arcediano Dam will be constructed. Aluminum exceeded the Mexican Criterion for Drinking Water Supply (MCDWS), at all sampling stations, whereas iron and manganese surpassed the criteria at some stations. Trace metals were below their respective criteria. For sediment samples in the river, chrome, copper and zinc exceeded the Canadian Interim Sediment Quality Guidelines (ISQG), whereas manganese and nickel exceeded the probable effect level (PEL). Other metals were below these limits. With exception of the El Salto sampling station, metals were mostly enriched in iron-containing sediments, followed by aluminum-containing clays and, to a lesser extent, by manganese oxides. Therefore, the interaction of metals with iron oxides was considered as the controlling adsorption mechanism. Simulations to estimate risks of water contamination by desorption of metals from sediments indicate that manganese and nickel may reach concentrations higher than the CDWS. In some cases, dissolved concentrations of lead and chrome may be higher than the respective CDWS, especially under conditions of high accumulation of sediments in the dam. Arsenic, copper and mercury concentrations did not exceed the CDWS under the simulated conditions.
Aguilar-Chavez A.,Mexican Institute for Water Technology |
Morales-Perez R.,Mexican Institute for Water Technology |
Laurel-Castillo J.A.,Mexican Institute for Water Technology |
Velez-Munoz H.,Metropolitan Autonomous University
Environmental Hydraulics: Theoretical, Experimental and Computational Solutions - Proceedings of the International Workshop on Environmental Hydraulics, IWEH 2009 | Year: 2010
In this paper, a two-dimensional hydrodynamic depth average model is implemented to investigate the dynamics of the circulation in the Manzanillo harbor. The model is mainly forced by tidal elevations. In order to validate the model a circulation field experiment was made with ADCP (Acoustic Doppler Current Profile) deployed at the harbor entrance and on a moving boat. The field data showed a baroclinic circulation pattern. However, the mean flow circulation was simulated satisfactorily. Finally, the model results are used to generate anenvironmental management tool for the API-Manzanillo (Harbor administration office). © 2010 Taylor & Francis Group, London.
Gelover-Santiago S.L.,Mexican Institute for Water Technology |
Perez-Castrejon S.,Mexican Institute for Water Technology |
Martin-Dominguez A.,Mexican Institute for Water Technology |
Villegas-Mendoza I.E.,Mexican Institute for Water Technology
Water Science and Technology | Year: 2012
This paper presents the results of a study on electrogeneration of aluminium, as a coagulant to remove silica in make-up water for cooling towers. Three electrochemical systems were tested, two with aluminium electrodes (one with polarity change and another without it), and a third one with aluminium anodes and cathodes of stainless steel. From the obtained results it was concluded that under the studied conditions, the most advantageous system to produce aluminium and remove silica is the one with both electrodes of aluminium working with direct current. Due to chemical production of aluminium at the cathode, the concentration of aluminium in the water at the outlet of the electrochemical reactor is much higher than the one calculated according to Faraday's law. Under the tested conditions it was possible to remove up to 66% of silica from water containing around 50 mg L -1. © IWA Publishing 2012.