Search results for "SEW"

Cost analysis of the facilities deterioration in wastewater treatment plants: A dynamic approach

2019

Abstract The implementation of the Directive 91/271 / CEE resulted in the proliferation of new Wastewater Treatment Plants (WWTPs) all around Europe. These facilities, which are compound by a wide range of assets (civil works, electromechanical equipment, pipelines, etc.), are ageing and deteriorating having an impact on the efficiency of the process. It is founded that repairs and corrective maintenance costs have increased in the last years, due to the deterioration process. Therefore, the aim of the present study is to focus on the cost effects of the deterioration process of the facilities in different wastewater treatment technologies. The analysis of these impacts will allow the opera…

Environmental Benefit of Improving Wastewater Quality: A Shadow Prices Approach for Sensitive Areas

2018

The use of effluents from wastewater treatment plants (WWTPs) as a non-conventional source of water for wetlands in arid and semi-arid regions is becoming the most-often sought solution for maintaining water flow in sensitive wetlands there. However, the managing effluent quality should be a requirement because excess nutrients (mainly nitrogen and phosphorus) can generate eutrophication problems in wetlands. In the Mediterranean area in general, wetlands are strongly vulnerable to eutrophication, which is why they are classified as sensitive areas. Our study uses a data set from 24 WWTPs, effluents of which are discharged to wetlands in the coast of Community of Valencia. We use the shado…

Performance assessment of water companies: A metafrontier approach accounting for quality of service and group heterogeneities

2021

Abstract The assessment of water companies’ efficiency, productivity and quality of service is part of the process to set water tariffs and therefore, is relevant for regulators and customers. However, the water industry involves several heterogeneous water companies. Following a pioneering approach, this study estimates productivity change and its drivers considering the non-homogeneous nature of the water companies and incorporating quality of service variables as undesirable outputs. In doing so, the metafrontier Malmquist Luenberger productivity index was estimated for a sample of English and Welsh water and sewerage companies (WaSCs) and water only companies (WoCs) over the years 2001–…

Editorial: Special Issue on Economics of Wastewater Treatment and Reuse

2018

Economic and environmental performance of wastewater treatment plants: Potential reductions in greenhouse gases emissions

2014

Abstract Sanitation and wastewater treatment are essential for protecting human health and environmental sustainability. Treatment processes are not free of environmental impacts; consequently assessment of the environmental performance of wastewater treatment plants (WWTPs) has gained interest in recent years. Unlike other methods, a direct approach is followed to estimate environmental performance indicators (EPIs) using data envelopment analysis (DEA), i.e. an index of overall performance is directly obtained. The present study represents pioneering work to integrate environmental impacts in the assessment of the efficiency of WWTP estimating pure (PEPI) and mixed (MEPI) environmental pe…

New European Wind Atlas: Mesoscale Atlas

2021

The mesoscale part of the New European Wind Atlas (NEWA) was created from WRF model simulations for all of Europe at a grid spacing of 3 km x 3 km, initially covering the 30 years from 1989 to 2018. The WRF model simulations (using WRF V3.8.1) were done in 10 partly overlapping domains using ERA5 reanalysis and OSTIA sea surface temperatures. We used many ensemble members to determine the most suitable configuration for the final production run. The model configuration, production and evaluation of the results against observations are described in Hahmann et al. (2020) and Dörenkämper et al. (2020).Data are accessible through doWIND, an instance of daTap (RESTfull API for data aggregation a…

Early-stage thermal performance design of thermo-active walls implemented in underground infrastructures

2022

Abstract Energy geostructures (EGs) represent an innovative technology in the sustainable energy agenda and are useful for satisfying the energy needs of the built environment. They are usually involving geostructures such as piles, walls, tunnels, shafts, and sewers. The application of such technology to infrastructure projects may have considerable thermal potential because of the large surfaces that can be thermally activated. This study focuses on thermo-active walls (energy walls, EWs), which are retaining structures used to sustain the sides of excavations. Key features related to their thermal design are examined, and a design methodology is proposed. The heat-exchange modes involvin…

DSC: software tool for simulation-based design of control strategies applied to wastewater treatment plants.

2011

This paper presents a computer tool called DSC (Simulation based Controllers Design) that enables an easy design of control systems and strategies applied to wastewater treatment plants. Although the control systems are developed and evaluated by simulation, this tool aims to facilitate the direct implementation of the designed control system to the PC of the full-scale WWTP (wastewater treatment plants). The designed control system can be programmed in a dedicated control application and can be connected to either the simulation software or the SCADA of the plant. To this end, the developed DSC incorporates an OPC server (OLE for process control) which facilitates an open-standard communic…

Cost modeling for sludge and waste management from wastewater treatment plants: an empirical approach for Spain

2013

Abstract Wastewater treatment involves the generation of large volumes of sludge and other waste. Managing this waste in an economical and environmentally acceptable way has become a matter of increasing importance over the last few years. While the technologies and processes to reduce sludge generation are being widely studied, research on the economic aspects is much more limited. This study applies a cost-modeling methodology that uses statistical information from a sample of Spanish wastewater treatment plants (WWTPs) to generate a sewage sludge and waste management cost function with the aim of contributing to a better understanding of the cost structure and predicting the cost savings…

A Banki–Michell turbine for in-line water supply systems

2017

The design of a novel Banki-Michell type turbine, to be located in existing water pipelines, is proposed. The turbine has a very efficient diffuser which allows the turbine to be compact and, most important, to have in-line flanges for minimal piping modifications at existing sites. This turbine combines a simple geometry with stable efficiency in a wide range of water discharges. The design procedure estimates the outer diameter of the impeller, its width and the geometry of the diffuser. A series of experimental tests has been carried out to measure the efficiency of the proposed turbine prototype. The turbine was tested in two different configurations, with and without rotational velocit…