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Objective: The goal of this work was to establish the quality conditions of the sediments retained in a constructedwetland/storage-tank, which are to be used as productive material. Materials and methods: Sediments were collected every fortnight for five months in 2016, with sediment traps specially designed for the study case, to analyze particle size distribution, total organic carbon, and heavy metals concentrations. Sediment and hydrological data processing were performed using principal component analysis and multiple correspondence analysis. Results: The maximum measured concentrations were 110.80 mg/kg, 263.25 mg/kg, 798.85 mg/kg, and 3067 mg/kg for Cr, Cu, Pb, and Zn respectively; for total organic carbon was 20.6 mg. The sediment particles were considered thin (D50 < 150μm). Interesting relationships between rainfall and sediment characteristics were found. In shorter dry seasons, higher particle diameter, lower concentrations of heavy metals, and higher concentrations of total organic carbon were seen. Conclusions: Sediments are suitable for use in activities such as land remediation, vegetation of soils that are not for agricultural use, and as materials for ornamental and recreational areas. It is possible to use the sediments in embankments as tolerable soil for fillings of concrete structures and culverts in the core or foundation area. [ABSTRACT FROM AUTHOR]

In this review, the factors affecting the transfer of oxygen in activated sludge processes using fine-pore diffusers for water resource recovery are critically discussed. In water resource recovery facilities, the energy required for aeration constitutes 50% to 80% of the total energy consumed by the plant. This critical review highlights the use of fine-pore diffuser aeration and emphasizes the significance of accounting for the following factors: diffuser aging and fouling, diffuser layout, diffuser type, selector benefits, local environmental conditions (temperature and atmospheric pressure), influent wastewater variability, dissolved oxygen control systems, and airflow rates. In our review, we were unable to find mathematical models that could be used to develop dynamic a-factor predictions and diffuser fouling predictions. Although the development of a model that considers all the factors that affect oxygen transfer efficiency (OTE) in activated sludge systems would be extremely valuable, the creation of such a model is outside the scope of this review. [ABSTRACT FROM AUTHOR]

This paper establishes an environmental impact assessment applied to brass threaded unions. Two different scenarios were analyzed based on the amount of material used in the process: i) 100% virgin raw material usage and ii) 92.3% of recycled material usage. For the analysis and environmental impact evaluation, this study made use of the life cycle assessment methodology (LCA). It also used Ecoindicator 99 for grading impact, as well as the computer tool Simapro® for calculations. When a composition of 100% virgin raw material was used, significant impacts were identified on mineral extraction and air suspended inorganic material categories. For 92.3% of recycled material, major effects were related to air suspended organic material and impact category related to acidification/eutrophication. The comparison of both scenarios made it possible to detect an impact attenuation in mineral extraction and air suspended inorganic material categories. As a consequence of using recycled material in the product, a significant global impact reduction of 231% in terms of Pt was noticed. [ABSTRACT FROM AUTHOR]

Rainwater collection for domestic uses represents an interesting practice from the economical and environmental point of view. However, this solution is adopted due to the threat of the scarcity of water resources; it is not neutral from a sanitary perspective. This paper presents an analysis of the economical and technical viability of the its use as an alternative for irrigation purposes, as well as cleaning of facades and hard areas in the campus of the Pontificia Universidad Javeriana (Bogota, Colombia). Three main aspects are developed in the paper: (i) estimation of the available rainwater volumes and the possible collection points; (ii) preliminary quality analysis of the collected rainwater; (iii) estimation of the construction costs for the basic infrastructure required to collect rainwater and estimation of the monetary savings obtained with the proposed solution. The results suggest that the use of rainwater is economically and technically viable, and that it may contribute with a sustainable management and development of the University's campus. [ABSTRACT FROM AUTHOR]

In this review, the factors affecting the transfer of oxygen in activated sludge processes using fine‐pore diffusers for water resource recovery are critically discussed. In water resource recovery facilities, the energy required for aeration constitutes 50% to 80% of the total energy consumed by the plant. This critical review highlights the use of fine‐pore diffuser aeration and emphasizes the significance of accounting for the following factors: diffuser aging and fouling, diffuser layout, diffuser type, selector benefits, local environmental conditions (temperature and atmospheric pressure), influent wastewater variability, dissolved oxygen control systems, and airflow rates. In our review, we were unable to find mathematical models that could be used to develop dynamic alpha factor predictions and diffuser fouling predictions. Although the development of a model that considers all the factors that affect oxygen transfer efficiency (OTE) in activated sludge systems would be extremely valuable, the creation of such a model is outside the scope of this review.This article is protected by copyright. All rights reserved. [ABSTRACT FROM AUTHOR]

This research performs life cycle analysis of threaded unions manufactured in PVC. The analysis proposes two scenarios according to the amount of recycled material used in the process. One of the scenarios is based on 45% of recycled material and the other one is based on 100% of raw virgin material usage. The analysis was made by means of the software tool Simapro® version 7.0, establishing the environmental impact rating by the Ecoindicator 99 methodology. Data were collected from databases, observation and measurement of an industrial process, specific prototype development under laboratory conditions and interviews with experts. When a composition of 100% of virgin raw material was used for the product, significant effects observed during the product's life cycle were related to fossil fuel consumption and the generation of inorganic materials in suspension. For a product composition with 45% of recycled material, the most significant effects were related to the generation of inorganic materials in suspension and climate change. Environmental impact diminution was observed in the fossil fuel consumption, acidification / eutrophication, inorganic materials in suspension and climate change categories. Using recycled material in this product lowers the contribution of fossil fuels to the environmental impact from 56% to 5%, compared to the contribution of the other impact categories. [ABSTRACT FROM AUTHOR]