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The global water supply is at an already critical level; around 3.9 billion people (47% of the world population) will be subject to water stress in 2050, according to the Organization for Economic Co-operation and Development (OECD). Unless advanced and alternative technology solutions are applied, construction of desalination facilities will continue to rise, leading to higher CO2 emissions. While desalination allows for the production of water from highly saline sources, it is considered an energy intensive process that is largely powered by fossil fuel sources. The natural interconnections between water and energy known as water-energy nexus has been widely recognized for desalination facilities; yet, there are tremendous amounts of cooling water that are still needed for condensing steam in the thermoelectric Rankine cycle to produce electricity; and large amounts of energy are typically required to transport and treat the water. For example, over 45 thousand cubic meter per hour of water are required to run a 500 MW power plant, for cooling and other process requirements. Moreover, large amounts of water vapour exit in the effluent flue gas from the combustion process. The amount of water that can be recovered from the flue gas is sufficient to substantially reduce the need for freshwater make-up. This represents a promising opportunity to exploit synergies among water and energy systems specifically for arid regions. In this paper, the aim is to identify suitable water recovery (dehydration hybrid) technologies that are capable of maximizing the recovery of water from flue gas in gas fired power plant-desalination plant coupled system. Specifically, compression and cooling, quenching, membrane separation and absorption alternatives are studied. The capacity of the power plant, the capacity of the desalination plant, fuel consumption of the power plant and energy requirement of the desalination facility are known. This work studies the technical, environmental and economic competing objectives when integrating the dehydration hybrid technology within the desalination-power plant complex. In this paper, the results for all the considered alternatives will be presented in terms of water recovery, energy savings, emissions reduction and economic indicators. The integrated low pressure quenching water recovery alternative has shown promising results, with up to 42% water recovery, while the integrated low pressure absorption alternative has demonstrated the highest figure in energy savings and emissions reduction with around 37%. These results can aid the decision on the suitable water recovery alternative to be used in the integrated energy-water complex. The authors acknowledge the support of Qatar University by the internal grant No QUCD-CENG-2018-2. Scopus

Made available in DSpace on 2022-04-28T17:22:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) According to the Brazilian National Water Resources Policy, water is a limited public good, and its management involves the participation of public authorities, users, and communities. This paper analyzes data on groundwater concession and uses in five Brazilian municipalities, located in the northeastern region of the Paraiba do Sul River Basin. Data were analyzed to associate aquifer systems and groundwater use with electricity consumption of the water supply systems and food production, in the perspective of the water-food-energy nexus. This analysis aimed to quantify the exploited water flows and if it is adequate with the capacity of the aquifers. For data analysis and interpretation, statistical techniques were used, which allowed structuring, organizing, and associating the information. The results indicate that, among the regional aquifer systems, the Cacapava System is the most explored in terms of groundwater abstraction, with an average of 9769 m(3)/h, of which only 1331 m(3)/h is used for public supply and 8456 m(3)/h for private use. One finding of this research was to verify that just one of the municipalities studied makes public the use of groundwater abstraction, with consequences in public policy and alerting to the need for adequate inspection in the areas of underground well-drilling for non-contamination and better maintenance of aquifer systems. The results highlight the water-food-energy nexus in the study area, indicating that municipalities with large rice cultivation areas use or store most of the water resources for agricultural use. Promoting new sustainable actions and achieving the Sustainable Development Goals requires integrated management outside the traditional sectors and water-food-energy nexus approach. Sao Paulo State Univ Unesp, Sch Engn, Chem & Energy Dept, Guaratingueta, Brazil Sao Paulo State Univ Unesp, Sch Engn, Elect Engn Dept, Guaratingueta, Brazil Sao Paulo State Univ Unesp, Sch Engn, Chem & Energy Dept, Guaratingueta, Brazil Sao Paulo State Univ Unesp, Sch Engn, Elect Engn Dept, Guaratingueta, Brazil CAPES: 001 CNPq: PQ 301853/2018-5

Traditional wastewater-based epidemiology (W-BE) relying on SARS-CoV-2 RNA detection in wastewater is attractive for understanding COVID-19. Yet traditional W-BE based on centralized wastewaters excludes putative SARS-CoV-2 reservoirs such as: (i) wastewaters from shared on-site sanitation facilities, (ii) solid waste including faecal sludge from non-flushing on-site sanitation systems, and COVID-19 personal protective equipment (PPE), (iii) raw/untreated water, and (iv) drinking water supply systems in low-income countries (LICs). A novel hypothesis and decision-support tool based on Wastewater (on-site sanitation, municipal sewer systems), solid Waste, and raw/untreated and drinking Water-based epidemiology (WWW-BE) is proposed for understanding COVID-19 in LICs. The WWW-BE conceptual framework, including components and principles is presented. Evidence on the presence of SARS-CoV-2 and its proxies in wastewaters, solid materials/waste (papers, metals, fabric, plastics), and raw/untreated surface water, groundwater and drinking water is discussed. Taken together, wastewaters from municipal sewer and on-site sanitation systems, solid waste such as faecal sludge and COVID-19 PPE, raw/untreated surface water and groundwater, and drinking water systems in LICs act as potential reservoirs that receive and harbour SARS-CoV-2, and then transmit it to humans. Hence, WWW-BE could serve a dual function in estimating the prevalence and potential transmission of COVID-19. Several applications of WWW-BE as a hypothesis and decision support tool in LICs are discussed. WWW-BE aggregates data from various infected persons in a spatial unit, hence, putatively requires less resources (analytical kits, personnel) than individual diagnostic testing, making it an ideal decision-support tool for LICs. The novelty, and a critique of WWW-BE versus traditional W-BE are presented. Potential challenges of WWW-BE include: (i) biohazards and biosafety risks, (ii) lack of expertise, analytical equipment, and accredited laboratories, and (iii) high uncertainties in estimates of COVID-19 cases. Future perspectives and research directions including key knowledge gaps and the application of novel and emerging technologies in WWW-BE are discussed., Graphical abstract Unlabelled Image