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An effective chemical conditioning technique was successfully tested and investigated to control and minimize the chemistry-related damages within mixed metallurgy steam and water cycle of Heller dry cooled combined cycle power plants (CCPPs), in which cooling water and condensate are completely mixed in direct contact condenser. This study aims to perform a comprehensive experimental research in four mixed metallurgy steam and water cycle.

A comprehensive experimental study was carried out in four mixed metallurgy steam and water cycle fabricated with ferrous- and aluminum-based alloys which have various corrosion resistance capabilities in contact with water. Chemical conditioning was conducted using both volatile and non-volatile alkalizing agents, and, to perform chemical conditioning effectively, quality parameters (pH, conductivity, dissolved oxygen, sodium, silica, iron, aluminum and phosphate) were monitored by analyzing grab and online samples taken at eight key sampling points.

Results indicated that pH was the most critical parameter which was not mainly within the recommended ranges of widely used standards and guidelines at all key sampling points that generally increases the occurrence of chemistry-related damages. The other quality parameters were mostly satisfactory.

In this research, the development of a suitable chemical conditioning technique in mixed metallurgy steam and water cycle, fabricated with ferrous and aluminum-based alloys, was studied. The obtained results in this thorough research work was evaluated by comparison with the chemistry limits of the widely used standards and guidelines, and combined use of volatile and solid alkalizing agents was considered as a promising chemical conditioning technique for utilization in mixed metallurgy units of Heller dry cooled CCPPs.

This paper aims to associate two fields of research: circular economy and the restoration of water cycle through the implementation of rainwater catchment systems in urban zones.

This study considers the case of the metropolitan zone of Guadalajara, México. This urban concentration is the second largest in Mexico. It faces floods each year with a cost of over US$26m, while demand of water has a production cost over US$24m. At the same time, the aquifers are drying due to uncontrolled urbanization and increasing the impervious area over the recharge zones. In addition, rainwater is combined with wastewater, elevating the cost of the wastewater treatment because the amount and quality of water to treat exceeds the systems’ capacity. This situation causes floods and decreases the availability of ground water. These problems are reflected in the imbalance of parameters of water cycle and a new approach is needed. The circular economy model can help to preserve one of our most vital resources. Scarcity is already so pronounced that we cannot reach many of our desired economic, social and environmental goals. Technologies that help balance supply and demand can also help water (both stock and flow) to become part of a circular model. To prove this, the authors present a hypothetical scenario based on a pilot project and a basin modeling of Guadalajara, Mexico.

Through this paper, it is possible to demonstrate that rainwater harvesting can play an important role in circular economy. Using the rainwater catchment systems, the cost of damages caused by floods could be decreased, the demand of water could be reduced, cost of production can be reduced, the aquifers can be recharged and the wastewater treatments can be improved.

Few papers have been developed to associate two fields of research (circular economy and the restoration of water cycle), using rainwater catchment systems as the central element.

The reliability of 0.4 mm pitch, 28 mm body size, 256‐pin plastic quad flat pack (QFP) no‐clean and water‐clean solder joints has been studied by temperature cycling and analytical analysis. The temperature cycling test was run non‐stop for more than 6 months, and the results have been presented as a Weibull distribution. A unique temperature cycling profile has been developed based on the calculated lead stiffness, elastic and creep strains in the solder joint, and solder data. Also, the thermal fatigue life of the solder joints has been estimated and correlated with experimental results. Furthermore, a failure analysis of the solder joints has been performed using scanning electron microscopy (SEM). Finally, a quantitative comparison between the no‐clean and water‐clean QFP solder joints has been presented.

The new campus of Tianjin University was designed, built and now operates following a green and sustainable concept. The campus’ eco-friendly water environment was formed by establishing a water recycling system. The campus is divided into three drainage sections based on the masterplan. Each drainage section adopts different methods of collecting, utilizing and discharging water according to specific conditions, aimed at achieving both high drainage capability and the efficient utilisation of rainwater. The campus was designed so runoff pollution is reduced through the utilisation of low-impact development methods, ensuring the quality of the recharge water. Through studying the fundamentals of treatment measures and models for simulating water quality, water circulation, constructed wetlands and pollution control of rain runoff, parameters for efficient water recycling could be mathematically forecast, ensuring that stakeholders can be continuously engaged in improving and preserving the water quality of landscaped water on campus. The overall system integrates a variety of measures being implemented into one cohesive entity, which contributes to establishing the sustainable and healthy water cycling system of the green campus.

The paper aims to discuss how life cycle assessment can be used in the early stage planning phase of new settlements.

By applying the life cycle methodology on the waste, water and wastewater system of a new carbon‐neutral settlement under planning in Norway, the authors discuss the pros and cons with applying this methodology in an early planning phase.

The LCA methodology enabled the authors to compare suggestions from interdisciplinary planning teams, relate them to the existing systems in Trondheim and provide quantitative results back to the decision‐makers, in this case the municipality. The environmental benefits of implementing alternative solutions in the waste, water and wastewater systems were found to be small.

Data availability and uncertainty can be limitations in the early planning phase.

By applying this methodology, the life cycle environmental impact of different solutions can be assessed at an early planning stage.

Even if life cycle assessment has been used for years in the research community, there is too little experience with applying the methodology in the early planning phase of new projects. This paper discuss how life cycle assessment can be used to compare suggestions from interdisciplinary planning teams, relate them to existing systems and provide quantitative results back to the decision‐makers.

Wastewater treatment plants (WWTPs) have long-time environmental impacts. The purpose of this paper is to assess the environmental footprint of two advanced wastewater treatment (WWT) technologies in a life cycle and sustainability perspective and identify the improvement alternatives.

In this study life cycle-based environmental assessment of two advanced WWT technologies (moving bed biofilm reactor (MBBR) and sequencing batch reactor (SBR)) has been carried out to compare different technological options. Life cycle impacts were computed using GaBi software employing the CML 2 (2010) methodology. Primary data were collected and analysed through surveys and on-site visits to WWTPs. The present study attempts to achieve significantly transparent results using life cycle assessment (LCA) in limited availability of data.

The results of both direct measurements in the studied wastewater systems and the LCA support the fact that advanced treatment has the best environmental performance. The results show that the operation phase contributes to nearly 99 per cent for the impacts of the plant. The study identified emissions associated with electricity production required to operate the WWTPs, chemical usage, emissions to water from treated effluent and heavy metal emissions from waste sludge applied to land are the major contributors for overall environmental impacts. SBR is found to be the best option for WWT as compared to MBBR in the urban context. In order to improve the overall environmental performance, the wastewater recovery, that is, reusable water should be improved. Further, sludge utilisation for energy recovery should be considered. The results of the study show that the avoided impacts of energy recovery can be even greater than direct impacts of greenhouse gas emissions from the wastewater system. Therefore, measures which combine reusing wastewater with energy generation should be preferred. The study highlights the major shortcoming, i.e., the lack of national life cycle inventories and databases in India limiting the wide application of LCA in the context of environmental decision making.

The results of this study express only the environmental impacts of the operation phase of WWT system and sludge management options. Therefore, it is recommended that further LCAs studies should be carried out to investigate construction and demolition phase and also there is need to reconsider the toxicological- and pathogen-related impact categories. The results obtained through this type of LCA studies can be used in the decision-making framework for selection of appropriate WWT technology by considering LCA results as one of the attributes.

The results of LCA modelling show that though the environmental impacts associated with advanced technologies are high, these technologies produce the good reusable quality of effluent. In areas where water is scarce, governments should promote reusing wastewater by providing additional treatment under safe conditions as much as possible with advanced WWT. The LCA model for WWT and management planning can be used for the environmental assessment of WWT technologies.

The current work provides a site-specific data on sustainable WWT and management. The study contributes to the development of the regional reference input data for LCA (inventory development) in the domain of wastewater management.

Nature-based solutions (NBS) generate different impacts at the urban scale, such as the ability to regulate water or store carbon, comparable to traditional, gray infrastructures in a more cost-efficient way. On the other hand, by their intrinsic nature, NBS do deliver a series of other services that are commonly defined as social, economic, and environmental cobenefits. These benefits are not always valued in a consistent and complete way, so there is the need to compile a more comprehensive evidence base on the social, economic, and environmental effectiveness of NBS. The chapter attempts to identify a categorization of the existing NBS and define the ecosystem services (ES) provided by them. Furthermore, starting from the results achieved through the definition of the existing NBS frameworks assessment, the chapter will identify a set of key performance indicators KPIs, based on the ES produced by NBS, to measure the economic, social, and environmental benefits generated in by NBS at the urban level taking into account their multifunctional character. In total, 66 key performance indicators have been individuated: 3 for provisioning services, 38 for regulating services, 17 for cultural services, and 8 for supporting services. Each indicator has been associated to a category of ES in order to measure and evaluate the performances of NBS implemented in cities.

The purpose is to open the possibility for a research institute, perhaps in partnership with a local council and a major developer, to bring together skills necessary to prototype the CEV development model.

This paper advances the development of a hypothetical, systems-based approach to the design and development of smart rural villages – a network of circular economy villages (CEVs). The method is to assimilate visionary ideas from 20th century town planning literature related to decentralisation and the development of new towns in rural areas, identifying key design principles. The present trajectory of infrastructure design and emerging development models are then analysed to modernise the design principles for implementation in the 21st century.

The availability of localised, renewable energy micro-grids potentially makes CEVs feasible and affordable. The shift to remote work and movement of people to regional areas suggests that this may be a desirable development form. This can only be confirmed through the development of a pilot project as proof of concept.

The proposed CEV development model applies circular economy strategies to every aspect of the smart rural village development including financing, ownership, spatial planning, design and material selection.

The purpose of this paper is to investigate design alternatives for pump‐included water distribution networks considering sustainability and reliability aspects. The aim is to demonstrate that CO₂ emissions could be reduced at a reasonable cost. The paper also investigates the trade‐offs between cost and reliability of water distribution networks.

An existing genetic algorithm optimization tool is customized in this research to perform multi‐objective optimization with various objectives and constraints. The developed model is demonstrated using a benchmark water distribution network.

The results from this research suggest that CO₂ emissions from water distribution networks could be reduced at a reasonable cost by choosing better objectives during the design stage. High system reliability could also be ensured for the lifetime by paying reasonable additional cost. This research presents various design alternatives for an engineer to choose from.

The design of water distribution networks is a computationally complex process and often requires significant CPU time to arrive at an optimal solution. This problem is significant in the case of larger networks, especially when all the failed states need to be simulated. Simpler measures of reliability could be adopted in the future.

Although a significant amount of research had been undertaken in the area of optimal water distribution network design, only limited research includes environmental impacts as a design objective. This paper not only includes environmental aspects but also considers reliability. The model proposed in this research is a useful tool for engineers for considering various alternatives before choosing the best design.

This study provides details on the development of a qualitative approach to the assessment of public evaluation of water recycling schemes. The approach involved the presentation to a small group of information and audiovisual material on the water cycle and wastewater treatment followed by the use of focus group style questioning to elicit discussion and questioning of the material. Qualitative analysis, based on a discursive method of evaluation, was used to assess dialogue in the groups, and it was concluded that participants used the context of the local scheme to assess their use of recycled water and consider extending the application of recycled water to more personal uses. Participants also tended to use item evaluation rather than category evaluation of water recycling. Agreement responses within workshops also influenced the discourse of evaluation of water reuse.