Search results for " desalination"

Exergetic and exergoeconomic analysis of a renewable polygeneration system and viability study for small isolated communities

2015

Abstract A great interest has recently arisen for the sustainable supply of energy and fresh water, due to the growing demand from developing countries. Facing this demand by traditional technologies implies evident risks related with the high cost of fossil fuels and their environmental impact. Then, alternative solutions based on the use of renewable sources and innovative technologies must be considered. In this paper a renewable polygeneration system is examined, which includes a solar field based on parabolic trough photovoltaic/thermal collectors, a biomass heater, an absorption chiller and a Multiple Effect Distillation desalination unit. Plant operation under dynamic conditions has …

Advanced energetics of a Multiple-Effects-Evaporation (MEE) desalination plant. Part II: Potential of the cost formation process and prospects for en…

2010

This paper represents the 2nd part of a paper in two parts. In part I a 2nd Principle analysis of a Multiple- Effects-Evaporation (MEE) process has been proposed. In this Part II perspectives for process improvement will be investigated, along two distinct research lines: the thermoeconomics-aided optimization of a new system and the increase of thermal efficiency for existing systems by a pinch-based plant retrofit. As concerns the first research line, a detailed productive structure for the plant stage (i.e. effect) examined in Part I is presented; the cost formation structure is then used to improve a simplified optimization process, revealing capable to properly reflect the interactions…

Experimental investigation of the effects of efficiency promoters in a MSF lab-scale unit

2006

Performance increase of membrane distillation pilot scale modules operating in vacuum-enhanced air-gap configuration

2019

Abstract This paper presents the first experimental evaluation at pilot scale of the operation of vacuum-enhanced air-gap membrane distillation (V-AGMD) using two commercial spiral-wound modules at Plataforma Solar de Almeria's solar desalination test facilities. The main difference between the modules was the channel length (1.5 and 2.7 m) as a result of having different membrane surface area (7.2 m2 and 25.9 m2 respectively) and different number of envelopes. Suction of air from the gap improved the vapour transfer through the membrane pores and the performance of the modules was significantly increased in relation to common air-gap (AGMD) operational mode, especially in the treatment of …

Analysis of the process of environmental impact assessment for seawater desalination plants in Spain

2014

Desalination generates drinking water and enhances the economic, social, and environmental development of many areas with few water resources, such as parts of the Middle East, North Africa, and southern Europe (such as Spain and Cyprus). Desalination plants may cause environmental impacts in coastal areas and so it is necessary to submit plans for new plants to a process of environmental impact assessment (EIA) in order to achieve more environmentally viable projects, meaning: optimal locations; appropriately used systems and technologies; effective preventive, compensatory, and corrective measures; and social and environmental acceptance. This article contains a study of the process of en…

Optimal design of cogeneration plants for seawater desalination

2004

Multi-stage flash (MSF) and reverse osmosis (RO) are the most common techniques for seawater desalination. A significant difference between these methodologies consists of their different energy requirements, i.e., thermal energy for MSF and mechanical energy for RO plants. The presence of both desalination systems (MSF and RO) appears to be suitable for cogeneration plants. The reject heat from the power cycle can feed an MSF section, while some power feeds the RO section and the MSF auxiliary equipment; the rest is sold to the grid. A criterion for the optimal design of such tri-functional cogeneration plants is proposed, based on exergo-economics and on profit maximization. In particular…

Renewable energy desalination: performance analysis and operating data of existing RES desalination plants

2015

Abstract: During the last decades, several small autonomous brackish or seawater desalination units driven by renewable energy sources (RES) have been developed within EU and non-EU projects around the world. A significant number of these units were designed, developed, and operated by research centers/universities, in collaboration with companies working in the field of RES and desalination, in their own premises (laboratories) in order to investigate the reliability and performance of the technologies matching in small-scale and autonomous operations. Some systems were also developed for the supply of fresh water to remote areas, and particularly to cover the needs of small villages or co…

CFD Modelling of the Demister in the Multi Stage Flash Desalination plant

2011

Abstract Demisters are used to remove entrained brine droplets from flashed off vapor within the flashing stages of the multi stage flash desalination process (MSF). This is necessary to prevent accumulation of brine droplets on the outside surface of the condenser tubes and contamination of the desalinated water. The aim of this work is to design a new demister with lower pressure drop and unaffected separation efficiency which can be later installed in the flashing stages of the MSF plant and causes reduction in the required heat transfer area. In this work the demister performance is predicted as a function of design (wire diameter), and operating parameters (stage temperature). This obj…

A novel 2D process model of electrodialysis units in cross-flow layout for the assessment of membrane deformation effects

2022

SOLAR DESALINATION: A CHALLENGE FOR SUSTAINABLE FRESH WATER IN THE 21ST CENTURY

2007

generate a sustainable source of fresh water as well as energy. This combination is highly valued as it limits and reduces air pollutant emissions and green house gases generated by combustion of fossil fuels. Increase in energy demand during the first half of this century is expected to continue, which makes the cost of renewable solar energy highly competitive against fossil fuels. Desalination has been relied on to provide fresh water for large cities and countries across the world. The desalination industry continues to grow in countries in arid regions. Various aspects of solar desalination processes, solar energy, and conventional desalination are discussed. Scenarios for combination …