The calculation of base flow rates in rivers is complex since hydrogeological and hydrological studies should be performed. The estimation of base flow rates in storm hydrograph associated to various return periods is even more challenging compared to other events. This research provides a novel methodology to compute base flow rates in gaged rivers for extreme events based on statistical correlations of daily flows. The current methodology does not require complex aquifers analysis to compute base flows. Results of computed base flow rates are validated using observed storm hydrographs using a complete record. The proposed methodology was applied considering measurements of a limnigraphic station in the Sinú river located in Montería, Córdoba, Colombia. The analysis confirmed that only using series of multiannual monthly mean flows is possible to estimate base flow of flood hydrograph associated to different return periods.
The objective of this study was to model an adsorption column bed with biomass residues using computational software to remove Pb (II) at the industrial level and analyse the effects of parametric variation. For this purpose, several simulations of the adsorption column were performed using Aspen Adsorption software, evaluating the effects of varied height, inlet flow rate, and initial concentration on the adsorption process performance. The Langmuir II and Freundlich models are established as isotherm models, and the linear driving force (LDF) model is established as the kinetic model. The findings showed that Freundlich–LDF obtained efficiencies of up to 99.9% and Langmuir II–LDF efficiencies of up to 99.7%. The optimal simulation conditions were a column height of 4 m, an initial Pb (II) concentration of 3000 mg/L, and an inlet flow rate of 250 m3/d. This study presents a novel engineering approach to predict the potential performance of columns packed with organic waste-derived biomasses in multi-scale Pb (II) removal using computer-aided engineering tools.
Spanish Abstract: El análisis del comportamiento de las bolsas de aire atrapadas en conducciones presurizadas es de gran importancia teniendo en cuenta los efectos que pueden ocasionar sobre el sistema hidráulico. El proceso del vaciado de agua en conducciones presurizadas necesita un análisis detallado debido a que se generan importantes depresiones que pueden producir el colapso del sistema dependiendo de las condiciones de instalación. Este artículo presenta el modelo matemático desarrollado por los autores y estudia numéricamente la influencia de las bolsas de aire atrapadas en una conducción de perfil irregular en la cual no se han instalado válvulas de aire (ventosas) o donde han fallado por problemas de mantenimiento. Los resultados muestran que para no solamente se alcanzan depresiones extremas sino que también el sistema no drenará completamente quedando parte de la columna de agua atrapada.
Microgrids are decentralized power production systems, where the energy production and consumption are very close to each other. Microgrids generally exploit renewable energy sources, encountering a problem of storage, as the power production from solar and wind is intermittent. This research presents a new integrated methodology and discusses a comparison of batteries and pumped storage hydropower (PSH) as energy storage systems with the integration of wind and solar PV energy sources, which are the major upcoming technologies in the renewable energy sector. We implemented the simulator and optimizer model (HOMER), which develops energy availability usage to obtain optimized renewable energy integration in the microgrid, showing its economic added value. Two scenarios are run with this model—one considers batteries as an energy storage technology and the other considers PSH—in order to obtain the best economic and technical results for the analyzed microgrid. The economic analysis showed a lower net present cost (NPC) and levelized cost of energy (LCOE) for the microgrid with PSH. The results showed that the microgrid with the storage of PSH was economical, with an NPC of 45.8 M€ and an LCOE of 0.379 €/kWh, in comparison with the scenario with batteries, which had an NPC of 95.2 M€ and an LCOE of 0.786 €/kWh. The role of storage was understood by differentiating the data into different seasons, using a Python model. Furthermore, a sensitivity analysis was conducted by varying the capital cost multiplier of solar PV and wind turbines to obtain the best optimal economic solutions.
• Fish by-products ( P. magdalenae scales/skeletons) were valorized into natural bio-coagulants (HAP/COL and COL). • High yields were achieved (HAP/COL over 50%), and the composite structure (hydroxyapatite and collagen) was confirmed by FTIR and XRD. • Both bio-coagulants demonstrated high turbidity removal efficiency (HAP/COL: 90–94%; COL: 95–99%). • A major drawback is that the final pH was too acidic (ranging from 4.1 to 5.1), falling below the minimum regulatory standard of 6.5. This study aimed to prepare a bio-coagulant using the scales and skeletons of Prochilodus magdalenae for application in turbidity removal from water. Hydroxyapatite/collagen (HAP/COL) and collagen in solution (COL) were extracted using the precipitation method and the ASH method, respectively. The obtained HAP/COL was dried and ground to a particle size of less than 1 mm. The resulting samples were characterised using FTIR, SEM-EDS, and XRD analyses. Yields of over 50% were achieved for HAP/COL and between 24% and 29% for COL. Following the confirmation of efficient production, the materials were applied as bio-coagulants and evaluated using the jar test method. Turbidity removal efficiency, pH, and conductivity were assessed according to the standards established in Resolution 2115 of 2007. The results demonstrated turbidity removal efficiencies ranging from 90% to 94% for HAP/COL and from 95% to 99% for COL. These removal rates were achieved within pH ranges of 4.1 to 5.1 for HAP/COL and 4.3 to 4.7 for COL, with conductivities ranging from 32 to 95 μS and 112 to 198 μS, respectively.
