Search Results (26)

This review explores hydrogen production via magnesium hydrolysis, emphasizing its role in the energy transition. Articles were selected from the Scopus database based on novelty. Magnesium’s abundance, high reactivity, and potential for recycling industrial waste make it a strong candidate for sustainable hydrogen production. A key advantage is the use of non-potable water, enhancing environmental and economic benefits. A major challenge is the passivating Mg(OH)₂ layer, which limits hydrogen release. Recent advances mitigate this issue through additives (metals, oxides, salts), alloying (Ni, La, Ca), mechanical treatments (ball milling, cold rolling), and diverse reaction media (seawater, acids, saline solutions). These strategies significantly improve hydrogen yields and kinetics, enabling industrial scalability. Magnesium hydrolysis exhibits a wide activation energy range (3.5–102.6 kJ/mol), highlighting the need for optimization in additives, concentration, temperature, and medium composition. Critical factors include additive selection, particle size control, and alloying, while secondary additives have a minimal impact. This review underscores magnesium hydrolysis as a promising, circular, economy-compatible method for hydrogen generation. Despite challenges in balancing efficiency and environmental impact, recent advancements provide a solid foundation for scalable, sustainable hydrogen production. Full article

The viability of the family-scale solar still (F-SSS) desalination plant in nine low- and middle-income Central American and Caribbean sites, with improper water treatment facilities and supply networks, has been analyzed and reported in detail. The sizing of the desalination plant was done based on the still’s performance, clean water requirement and solar radiation potential. The still’s performance was estimated using an experimentally validated thermodynamic model. Annual desalinated water productivity per still was about 979.0 L (highest) and 836.0 L (lowest) in Port-au-Prince and Belize City, respectively. The lowest and highest potable water production price was observed in Havana (19.75 to 20.22 USD/m³) and Port-au-Prince (59.23 to 60.62 USD/m³) due to their low and high local interest rates, respectively. The decarbonization potential of the F-SSS desalination plant with a 25-year lifetime ranged between 37 and 641 tons of CO₂ emission. The specific CO₂ generated was found to be the least and highest in San Salvador (4.24 to 4.34 g/L of desalinated water) and Port-au-Price (13.70 to 14.04 g/L of desalinated water), respectively. The energy, finance payback time and sustainability index of the F-SSS desalination plant ranged between 0.59 and 0.67 years, 1.2 and 18.0 months, and 1.03 and 1.04, respectively. The performance, economic and environmental aspects revealed positive signs on the applicability of the F-SSS desalination plant in Central American and Caribbean sites for reliable and sustainable clean water supply. However, this process can be ratified if the concerned governments implement a reasonable subsidy, as is the case with other renewable energy systems. Full article

Chromium is an essential element in various industrial processes, including stainless steel production, electroplating, metal finishing, leather tanning, photography, and textile manufacturing. However, it is also a well-documented contaminant of aquatic systems and agricultural land, posing significant economic and health challenges. The hexavalent form of chromium [Cr(VI)] is particularly toxic and carcinogenic, linked to severe health issues such as cancer, kidney disorders, liver failure, and environmental biomagnification. Due to the high risks associated with chromium contamination in potable water, researchers have focused on developing effective removal strategies. Among these strategies, biosorption has emerged as a promising, cost-effective, and energy-efficient method for eliminating toxic metals, especially chromium. This process utilizes agricultural waste, plants, algae, bacteria, fungi, and other biomass as adsorbents, demonstrating substantial potential for the remediation of heavy metals from contaminated environments at minimal cost. This review paper provides a comprehensive analysis of various strategies, materials, and mechanisms involved in the bioremediation of chromium, along with their commercial viability. It also highlights the advantages of biosorption over traditional chemical and physical methods, offering a thorough understanding of its applications and effectiveness. Full article

Different approaches have been suggested for the waste heat recovery of high-temperature exhausted gas of a solid oxide fuel cell (SOFC). In such systems, mostly gas turbine (GT) and organic Rankine cycle (ORC) are added as bottoming systems to the SOFC (Configuration 1). However, the SOFC-GT-ORC has a considerable amount of waste energy which can be recovered. In the present research, the waste energy of ORC in the heat rejection stage and the residual exhausted gas of the system were recovered by a thermoelectric generator (TEG) and a hot water unit, respectively. Then, the extra produced power in the TEG was directed to a proton exchange membrane electrolyzer and a reverse osmosis desalination unit (RODU) for hydrogen and potable water outputs. The performance of SOFC-GT, Configuration 1, and Configuration 2 was compared through a 4E (energy, exergy, exergy-economic, and environmental) analysis. In the best performance point, the exergy efficiency and unit cost of product (UCOP) of SOFC-GT were obtained as 69.41% and USD 26.53/GJ. The exergy efficiency increased by 2.56% and 2.86%, and the UCOP rose by 0.45% and 12.25% in Configurations 1 and 2. So, the overall performance of Configuration 1 was acceptable and Configuration 2 led to the highest exergy efficiency, while its economic performance was not competitive because of the high investment cost of RODU. Full article

The primary aim of this review article is to find the influence of wastewater and its characteristics on recycling as an alternative to potable water for concrete preparation. On the other hand, scarcity, and the demand for freshwater for drinking are also increasing day by day around the globe. About a billion tons of freshwater is consumed daily for concrete preparation for various operations such as mixing and curing, to name a few. The rapid development of certain industries such as textile, casting, stone cutting, and concrete production has caused the water supply to be severely affected. Recycling wastewater in concrete offers various potential benefits like resource conservation, environmental protection, cost savings, and enhanced sustainability. This article reviews the effect of various types of wastewater on various physical and chemical properties of wastewater, rheological characteristics, strength, durability, and microstructure properties of concrete. It also explores the potential effects of decomposing agents on enhancing concrete properties. Currently, limited research is available on the use of various types of wastewater in concrete. Hence, there is a need to develop various methods and procedures to ensure that the utilization of wastewater and treated wastewater is carried out in the production of concrete in a sustainable manner. Although wastewater can reduce the workability of fresh concrete, it can also increase its strength and long-term performance of concrete. The use of various types of wastewater, such as reclaimed water and tertiary-treated wastewater, was found to be superior compared to those using industrial- or secondary-treated wastewater. Researchers around the globe agree that wastewater can cause various detrimental effects on the mechanical and physical properties of concrete, but the reductions were not significant. To overcome limited scientific contributions, this article reviews all the available methods of using various types of wastewater to make concrete economically and environmentally friendly. This research also addresses possible challenges with respect to the demand for freshwater and the water crisis. Full article

To implement sustainable water resource management, the industries that produce a huge amount of wastewater are aiming to recycle wastewater. Reverse osmosis (RO) is an advanced membrane process that can produce potable water from wastewater. However, the presence of diverse pollutants in the wastewater necessitates effective pretreatment to ensure successful RO implementation. This study evaluated the efficiency of microfiltration (MF) and ultrafiltration (UF) as two pretreatment methods prior to RO, i.e., MF-RO and UF-RO, for recycling poultry slaughterhouse wastewater (PSWW). The direct treatment of PSWW with RO (direct RO) was also considered for comparison. In this study, membrane technology serves as a post treatment for PSWW, which was conventionally treated at Sanderson Farm. The results demonstrated that all of the processes, including MF-RO, UF-RO, and direct RO treatment of PSWW, rejected 100% of total phosphorus (TP), over 91.2% of chemical oxygen demand (COD), and 87% of total solids (TSs). Total nitrogen (TN) levels were reduced to 5 mg/L for MF-RO, 4 mg/L for UF-RO, and 9 mg/L for direct RO. In addition, the pretreatment of PSWW with MF and UF increased RO flux from 46.8 L/m² h to 51 L/m² h, an increase of approximately 9%. The product water obtained after MF-RO, UF-RO, and direct RO meets the required potable water quality standards for recycling PSWW in the poultry industry. A cost analysis demonstrated that MF-RO was the most economical option among membrane processes, primarily due to MF operating at a lower pressure and having a high water recovery ratio. In contrast, the cost of using RO without MF and UF pretreatments was approximately 2.6 times higher because of cleaning and maintenance expenses related to fouling. This study concluded that MF-RO is a preferable option for recycling PSWW. This pretreatment method would significantly contribute to environmental sustainability by reusing well-treated PSWW for industrial poultry purposes while maintaining cost efficiency. Full article

Innovation has been the transforming tool of precision agriculture as a response to population growth and the demand for more food with quality, less waste, food security, and sustainable management of environmental resources. The challenges are to increase the productivity of cultivated areas, both for current and future areas, to manage the use of potable water, scarce in many regions, to keep the soil fertile, and to reduce waste through reuse, optimization, resource sharing, and operational and strategic management based on accurate information of planting, harvesting, and management of environmental conditions, which are also objectives of the Circular Economy. Therefore, using Industry 4.0 technologies in agriculture becomes fundamental to facing such challenges. This paper presents a systematic literature review on Industry 4.0 technologies adopted in agriculture for sustainable development, considering environmental, economic, and social benefits. The research pointed to the use of IoT in irrigation control systems by sending automatic commands, monitoring soil and weather conditions, in the use of machinery with some automation features and in cloud data storage systems, and with the use of Big Data analytical tools, with access by mobile devices, these uses contribute to operational and strategic decision making in the management of planting and harvesting. However, the literature review did not find a technological architecture for Integrated Services in Agriculture 4.0. Thus, this paper proposes a Service Architecture that enables the promotion of a Circular Economy in Agriculture 4.0. The contribution of this article to the theory is in the expansion of knowledge of the use of technologies in Agriculture 4.0. In terms of practice, this article provides an Integrated Service Architecture so that new products can be developed for Agriculture 4.0 and thus contribute to society in reducing food insecurity, generating environmental, economic, and social benefits, and promoting the Circular Economy in Agriculture 4.0. Full article

Groundwater is an essential water source for drinking, domestic, irrigation and industrial production in Luxi Plain, Shandong Province, China. Understanding the spatial–temporal changes in groundwater quality and its influencing factors in the region were required for better utilization of groundwater resources and efficient design of groundwater management strategies. In this study, the hydrochemical characteristics of groundwater in the study area were analyzed, and significant evolution was found from 2018 to 2020 due to silicate and carbonate weathering, evaporation and human activities. Moreover, the entropy water quality index (EWQI) was used to assess groundwater quality from 2018 to 2020. The EWQI values in 2018–2020 were 129.5, 90.5 and 94.0, respectively, and 31.7% of the groundwater in 2019 and 20.0% in 2020 can be used directly for drinking in the study area; others can be used for domestic water or irrigation. The potable groundwater, with an EWQI value of <50 (ranked as class Ⅰ or Ⅱ water quality), was mainly distributed in the west and southeast of the study area. The potential health risk due to oral intake and dermal intake was further assessed based on the human health risk assessment (HHRA) model. The results showed that, 37.3%, 6.7% and 3.3% of the groundwater samples for adults exceeded the acceptable limit for non-carcinogenic risk of 1.0 in 2018–2020, while for children, they were 88.2%, 30.0% and 56.7%, respectively. The high non-carcinogenic risks virtually all occurred in the counties or districts with higher agricultural or economic values. This work may provide useful information for local groundwater conservation and management and help to ensure a sustainable and healthy water supply for drinking, domestic and agricultural needs. Full article

Water infrastructure integrity, quality, and distribution are fundamental for public health, environmental sustainability, economic development, and climate change resilience. Ensuring the robustness and quality of water infrastructure is pivotal for sectors like agriculture, industry, and energy production. Machine learning (ML) offers potential for bolstering water infrastructure integrity and quality by analyzing extensive data from sensors and other sources, optimizing treatment protocols, minimizing water losses, and improving distribution methods. This study delves into ML applications in water infrastructure integrity and quality by analyzing English-language articles from 2015 onward, compiling a total of 1087 articles. Initially, a natural language processing approach centered on topic modeling was adopted to classify salient topics. From each identified topic, key terms were extracted and utilized in a semi-automatic selection process, pinpointing the most relevant articles for further scrutiny, while unsupervised ML algorithms can assist in extracting themes from the documents, generating meaningful topics often requires intricate hyperparameter adjustments. Leveraging the Bidirectional Encoder Representations from Transformers (BERTopic) enhanced the study’s contextual comprehension in topic modeling. This semi-automatic methodology for bibliographic exploration begins with a broad topic categorization, advancing to an exhaustive analysis of each topic. The insights drawn underscore ML’s instrumental role in enhancing water infrastructure’s integrity and quality, suggesting promising future research directions. Specifically, the study has identified four key areas where ML has been applied to water management: (1) advancements in the detection of water contaminants and soil erosion; (2) forecasting of water levels; (3) advanced techniques for leak detection in water networks; and (4) evaluation of water quality and potability. These findings underscore the transformative impact of ML on water infrastructure and suggest promising paths for continued investigation. Full article

The sale of ready-to-eat (RTE) street food represents an important source of income in many developing countries. However, these foods are frequently implicated in outbreaks of gastrointestinal diseases. Street food vendors face several constraints that hamper improvement in the microbiological quality of their products. The aim of this review was to update knowledge about the main causes of foodborne illnesses in developing countries, including the growing concern with the microbial transmission of antibiotic resistance. Following PRISMA guidelines, this systematic review was conducted on original articles published from January 2010 to July 2023. The search was carried out using Scopus, PubMed, Web of Science, Food Science and Technology Abstracts (FSTA), the International Information System for Agricultural Sciences and Technology (AGRIS), as well as isolated searches of relevant articles from Google Scholar. The initial search identified 915 articles, 50 of which were included in this systematic review. The results indicate that, in the majority of the 15 countries examined, women constitute the predominant segment of street food vendors, representing more than 55% of the total number of these vendors. In 11 countries, street food vendors under the age of 18 were identified. Most vendors had a low level of education and, consequently, were unaware of good hygiene practices when handling food. The combination of factors such as poor hygiene practices on the part of food handlers and the lack of facilities, namely, the absence of available potable water, were frequently listed as the main causes of food contamination. Enterobacteriaceae such as Escherichia coli (61.9%), Salmonella (30.1%), and Shigella spp. (9.5%), as well as Staphylococcus aureus (30.1%) and Listeria monocytogenes (14.3%), were the most common pathogens found in RTE street foods. In 22 studies from 13 developing countries, 59% (13/22) reported high multidrug resistance in Enterobacteriaceae (40% to 86.4% in E. coli, 16.7 to 70% in Salmonella, and 31 to 76.4% in S. aureus). To address the challenges faced by street vendors and improve their economic activities, it is necessary for government entities, consumers, and vendors to work together collaboratively. Full article

Emerging hybrid technologies have better potential than conventional technology for diversifying the desalination industry, which is presently being dominated by thermal and membrane-based desalination. Notwithstanding the technological maturity of the desalination processes, they remain highly energy-intensive processes and have certain disadvantages. Therefore, the hybridization of thermal and membrane desalination processes holds great attention to mitigate limitations of individual processes in terms of energy consumption, quality and quantity of potable water, overall efficiency and productivity. This paper provides an oversight of conventional and developing desalination technologies, emphasizing their existing state and subsequent potential to reduce water scarcity. Conventional hybrid desalination systems (NF-RO-MSF, MED-AD, FO-MED, MSF-MED, RO-MED, RO-MSF and RO-MD) are briefly discussed. This study reveals that the integration of solar thermal energy with desalination has a great potential to substantially reduce greenhouse emissions besides providing the quality and/or quantity of potable water in cost-effective ways. Due to its abundant availability with minimal/no carbon footprint and the ability to generate both thermal and electrical energy, solar energy is considered better than other renewable energy technologies. The findings further suggest that hybrid desalination systems are technically sound and environmentally suitable; however, a significant study of the research process and development is still required to make this technology efficient and economically viable. Full article

One of the most effective strategies to mitigate water shortages worldwide is to reuse treated wastewater for freshwater production employing reverse osmosis (RO) technology. This strategy is appropriate in urban areas of arid or semi-arid regions as it can provide a sustainable and reliable water source close to the consumers. One of the drawbacks of RO is the high variability of production costs due to the electricity intensity. In addition, depending on the electricity source, it can also result in substantial environmental costs. This study showed that upgrading pumping and RO membrane systems of a wastewater reuse plant in Cyprus can significantly alleviate these drawbacks in terms cost, water recovery rate, and air pollution. The water-recovery rate of the upgraded RO plant increased from 43.2 to 75 percent, which resulted in a substantial net financial benefit due to the reduction in the quantity of wastewater purchased and the increase in potable water produced. The upgraded system also reduced the electricity requirement from 3.63 kWh/m³ to 1.92 kWh/m³. Pollution emissions decreased substantially because of the reduction in electricity requirements. The beneficiaries of these lower emission costs are the residents of Cyprus and global society. Overall, the benefit of upgrading the plant is highly attractive with more than 65 percent annual real internal rates of return in financial and economic terms. Positive net present values are realized for all the scenarios considered. Full article

This paper shows the technical–economic assessment of two power systems based on renewable electricity to cover the energy consumption requirements of a drinking water treatment plant in the town of Pile, Ecuador, with a planning horizon of 15 years. A stand-alone and a grid-connected solar PV system were proposed to power this plant, which was designed considering the maximum daily potable water supply condition. This plant operated under two scenarios: (1) 12 h during daylight hours and (2) 24 h. Both schedules were proposed to assess the impact of PV power systems on plant operation. We modeled and optimized a total of four scenarios, where each scenario consisted of one of the proposed PV power systems and the plant with one of its operating schedules. Homer Pro software was used to size and find an optimal solution in each scenario, considering the net present cost (NPC) as the main criterion for optimization. The results showed that the change in the plant operation schedule significantly influenced the parameters of each scenario, such as component sizing, electricity production, initial capital, NPC, and electricity purchase/sale capacity from the plant as a grid power service user to the electric utility company. Full article

Water quality and disposability are among the main challenges that governments and societies will outside during the next years due to their close relationship to population growth and urbanization and their direct influence on the environment and socio-economic development. Potable water suitable for human consumption is a key resource that, unfortunately, is strongly limited by anthropogenic pollution and climate change. In this regard, new groups of compounds, referred to as emerging contaminants, represent a risk to human health and living species; they have already been identified in water bodies as a result of increased industrialization. Pesticides, cosmetics, personal care products, pharmaceuticals, organic dyes, and other man-made chemicals indispensable for modern society are among the emerging pollutants of difficult remediation by traditional methods of wastewater treatment. However, the majority of the currently used waste management and remediation techniques require significant amounts of energy and chemicals, which can themselves be sources of secondary pollution. Therefore, this review reported newly advanced, efficient, and sustainable techniques and approaches for water purification. In particular, new advancements in sustainable membrane-based filtration technologies are discussed, together with their modification through a rational safe-by-design to modulate their hydrophilicity, porosity, surface characteristics, and adsorption performances. Thus, their preparation by the use of biopolymer-based gels is described, as well as their blending with functional cross-linkers or nanofillers or by advanced and innovative approaches, such as electrospinning. Full article

In this study, high concentration wastewater from ready-mixed concrete plants was used to replace potable water as mixing water of concrete, with replacement rates of 0%, 25%, 50%, 75%, and 100%, by weight. The solid content of the wastewater was 12%. Five groups of C20 concrete mix proportions were designed. Different concrete properties, including workability, compressive strength and durability under freeze–thaw cycles, carbonization, and drying conditions, were studied, and the effect of the increase in the proportion of wastewater as a replacement for potable water was investigated. The microstructural attributes of the developed C20 concrete were studied through X-ray diffraction (XRD), thermal analysis (TG-DSC), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), and mercury intrusion porosimetry (MIP). Finally, the economic benefits of replacing potable water with wastewater were analyzed. The results indicate that using wastewater for concrete mixing reduces workability and a superplasticizer is needed to ensure adequate concrete workability. At the ages of 7, 28, and 56 days, with the increase in the proportion of wastewater as a replacement for potable water (0, 25%, 50%, 75%, 100%), the compressive strength of concrete shows a trend of first decreasing, then increasing, and then decreasing. When the proportion of wastewater replacing potable water is 75%, the concrete compressive strength is the highest. The microstructure showed that the main products of wastewater-mixed concrete are calcite (CaCO₃), portlandite (Ca(OH)₂), ettringite (Aft), and calcium silicate hydrate (C-S-H). Adding wastewater to concrete does not lead to the formation of new products in the concrete. Wastewater can fill the concrete pores well, thus optimizing the pore structure. When the proportion of wastewater replacing potable water is 75%, C20 concrete has the densest microstructure, lower porosity, and better pore structure. Durability properties further indicate that 25%, 50%, and 75% of wastewater replacing potable water can improve the concrete’s frost resistance. However, there is a negative impact on the carbonation resistance of wastewater. Wastewater replacing 75% potable water by weight can improve the drying shrinkage of concrete. The recycling of wastewater is not only green and environmentally friendly but also has good economic and environmental benefits. Full article