Search Results (50)

The olive oil sector constitutes a fundamental pillar in the Mediterranean region from socio-economic and cultural perspectives. Nonetheless, it produces significant amounts of waste, leading to numerous environmental issues. These waste streams contain valuable compounds that can be recovered and utilized as inputs for various applications. This study introduces a novel value chain for olive wastes, focused on extracting lignin from olive pomace by ionic liquids and polyphenols from olive mill wastewater, which are then incorporated as hybrid nanoparticles in the formulation of an innovative starch-based biofertilizer. This biofertilizer, obtained by using residual wastewater as a source of soluble nitrogen, acting at the same time as a plasticizer for the biopolymer, was demonstrated to surpass traditional NPK biofertilizers’ efficiency, allowing for root growth and foliage in drought conditions. In order to recognize the environmental impact due to its production and align it with the technical output, the circularity and environmental performance of the proposed system were innovatively evaluated through a combination of Life Cycle Assessment (LCA) and the Material Circularity Indicator (MCI). LCA results indicated that the initial upcycling process was potentially characterized by significant hot spots, primarily related to energy consumption (>0.70 kWh/kg of water) during the early processing stages. As a result, the LCA score of this preliminary version of the biofertilizer may be higher than that of conventional commercial products, due to reliance on thermal processes for water removal and the substantial contribution (56%) of lignin/polyphenol precursors to the total LCA score. Replacing energy-intensive thermal treatments with more efficient alternatives represents a critical area for improvement. The MCI value of 0.84 indicates limited potential for further enhancement. Full article

The global energy crisis, driven by factors such as increased demand, limited fossil fuel resources, and growing environmental concerns created an urgent need for energy-efficient solutions across all sectors. Among these, refrigeration systems, which are used extensively in both domestic and commercial settings, are responsible for a sizeable amount of global energy consumption. Finding ways to reduce energy used in the refrigeration could play a crucial role in mitigating the energy crisis. Phase Change Materials (PCMs) have emerged as a promising technology to enhance the energy efficiency of refrigeration systems. By storing and releasing energy in the form of latent heat, PCMs optimize energy conversion rate of the processes, reduce power consumption, and lower the overall environmental impact. The present research focus Calcium Chloride Hexahydrate (CCH) as the PCM which acts as an intermediary between the heat sources to achieve optimal effectiveness. To improve system performance and optimize PCM quantity, two novel system configurations were assessed in the mass proportions of 1 kg and 2 kg of PCM with water. The incorporation of PCZ enhanced the overall heat energy utilisation, recovery of waste heat, and greater system output. And actual COP of the refrigeration system was meet out with the domestic refrigerator in ranges of 1.0759 to 1.1537. The above two novel system were proved that a vital role in removal of waste latent heat into lateral use in the ranges of 110.8 kJ (min.) into 226.8 kJ (max.). Finally proposed system was avoided global warming temperature raise because of uses of waste heat into lateral uses in the refrigeration systems. Full article

This paper presents a theoretical and experimental investigation into improving the energy efficiency of electrically heated systems through thermal energy recovery. Enhancing efficiency in such systems can significantly reduce energy consumption, operating costs, and greenhouse gas emissions, particularly when electricity is generated from fossil fuels. Commercial dishwashers are inherently energy-intensive due to the need for rapid and effective cleaning. Regulatory and market pressures increasingly encourage manufacturers to develop energy-efficient technologies. This study aimed to design, develop, and incorporate a miniaturized heat exchanger to recover waste thermal energy and reduce the overall energy consumption in a commercial dishwasher. In collaboration with Norris Industries, the University of Newcastle trialed a retrofitted internal heat exchanger in representative commercial dishwasher models. The device was designed to transfer heat from discharged wash water to preheat incoming freshwater. The heat exchanger was developed based on a theoretical thermal analysis and engineered for practical integration. Experimental testing demonstrated that the system achieved up to a 50% reduction in energy use without compromising the cleaning performance or increasing the manufacturing complexity. This approach offers a scalable and effective solution for enhancing energy efficiency in commercial dishwashing. Its broader implementation could substantially reduce the energy demand and greenhouse gas emissions across the sector. Full article

The agricultural sector in the Mediterranean Basin is the largest consumer of water, using 70% of freshwater resources for crop irrigation, which accounts for 85% of the region’s agricultural output. With climate change and population growth expected to reduce water availability, energy management also poses a significant challenge, as 7% of commercial energy is used for freshwater supply. The DIONYSUS project aims to develop practical adaptation solutions for efficient resource use through innovative business models, focusing on four demonstration sites in Egypt, Greece, Morocco, and Italy. It seeks to promote a transition to a Green Economy by engaging stakeholders and utilizing a Cross-Sectoral Nexus adaptation tool. Full article

The autonomy of transport systems presents a transformative opportunity to enhance logistics efficiency, improve safety, and support decarbonization. In the maritime sector, the International Maritime Organization (IMO) has been working since 2016 to develop a mandatory regulatory framework for Maritime Autonomous Surface Ships (MASSs), aiming to finalize a comprehensive code. Simultaneously, pilot projects are underway in national waters under the oversight of national administrations. Naval applications of autonomous ships demonstrate their potential, as emerging doctrines highlight their strategic and operational advantages. Although the military sector is not governed at the international level, safely managing interactions between military and commercial MASSs is crucial for ensuring safe navigation. Classification societies play a vital role in achieving high safety standards and ensuring regulatory compliance. This study aims to propose a framework for certifying maritime autonomous vessels. Through a thorough analysis of the existing literature and by identifying gaps, this study outlines a structured pathway to facilitate the certification and operation of MASSs, addressing key technical, operational, and safety considerations. This research contributes to designing a risk-informed approach for the development of autonomous surface vehicles. Full article

The amount of non-revenue water, mostly due to leakage, is around 126 billion cubic meters annually worldwide. A more efficient wastewater management strategy would use a parametric design for on-demand, customized pipe fittings, following the principles of distributed manufacturing. To fulfill this need, this study introduces an open-source parametric design of a 3D-printable easy-connect pipe fitting that offers compatibility with different dimensions and materials of pipes available on the market. Custom pipe fittings were 3D printed using a RepRap-class fused filament 3D printer, with polylactic acid (PLA), polyethylene terephthalate glycol (PETG), acrylonitrile styrene acrylate (ASA), and thermoplastic elastomer (TPE) as filament feedstocks for validation. The 3D-printed connectors underwent hydrostatic water pressure tests to ensure that they met the standards for residential, agricultural, and renewable energy production applications. All the printed parts passed numerous hydrostatic pressure tests. PETG couplings can tolerate up to 4.551 ± 0.138 MPa of hydrostatic pressure, which is eight times greater than the highest standard water pressure in the residential sector. Based on the economic analysis, the cost of 3D printing a pipe coupling is from three to seventeen times lower than purchasing a commercially available pipe fitting of a similar size. The new open-source couplings demonstrate particular potential for use in developing countries and remote areas. Full article

The study describes the distribution of fish farming activities, identifies and characterizes the stakeholders involved, and assesses their level of knowledge and the techniques used for fish farming in the Territory of Mbanza-Ngungu. Furthermore, it proposes avenues to improve the sustainability and profitability of the sector. The methodology relied on a snowball approach to recruit a representative sample of 350 fish farmers. Field visits allowed for detailed data collection through a specially designed questionnaire. The data were analyzed using statistical methods (chi-square test of independence) to identify trends and challenges across the sectors of the territory of Mbanza-Ngungu. The findings revealed that fish farming activities are distributed across the territory of Mbanza-Ngungu, with a male predominance (96%) among fish farmers and a growing trend of this activity among older individuals over 40 years old (48%). Additionally, the results demonstrate that aquaculture is mainly a secondary activity for 97% of respondents, yet it could play a pivotal role in household economic diversification. The study identifies predominant practices, such as extensive farming (89%) and monoculture (92%), while highlighting gaps in pond management and fish farmers’ general knowledge. Challenges are mainly related to feed access (28%), financing (27%), training (23%), and water quality monitoring (100%). The commercial orientation of production towards sales (94%) rather than self-consumption offers an opportunity to improve this sector in this territory. Finally, recommendations are made to enhance the sustainability and profitability of aquaculture in the region, including promoting integrated practices, more efficient pond management practices, and aquaculture product processing. Full article

Water, a fundamental and indispensable resource necessary for the survival of living beings, has become a pressing issue in numerous regions worldwide due to scarcity. Urban areas, where the majority of the global population resides, witness a substantial consumption of blue water, particularly in commercial buildings. This study investigates the potential for enhancing water efficiency within an ongoing high-rise office building construction situated in a tropical climate. The investigation utilizes the green building guidelines of leadership in energy and environmental design (LEED) through a case-study-based research approach. Strategies included using efficient plumbing fixtures (such as high air–water ratio fixtures and dual-flush toilets), the selection of native plants, implementing a suitable irrigation system, introducing a rainwater harvesting system (RWHS) and improving the mechanical ventilation and air conditioning (MVAC) system. The results showed a 55% reduction in water use from efficient fixtures, a 93% reduction in landscaping water needs and a 73% overall water efficiency with a RWHS from the baseline design. Additionally, efficient cooling towers and the redirection of condensed water into the cooling tower make-up water tank improved the overall water efficiency to 38%, accounting for the water requirements of the MVAC system. The findings of this study can contribute to more sustainable and water-efficient urban development, particularly in regions facing water scarcity challenges. The significance of these findings lies in their potential to establish industry standards and inform policymakers in the building sector. They offer valuable insights for implementing effective strategies aimed at reducing blue water consumption across different building types. Full article

The Renewable Energy Directive II introduces renewable energy communities, enhancing energy sharing. However, many existing initiatives, focussing only on electricity, overlook the substantial energy demand in building sector comprising residential and commercial spaces. Energy communities in this sector can leverage district heating and cooling technology for thermal energy sharing, contributing to carbon neutrality by enhancing efficiency and reducing primary energy usage. Advanced strategies such as integrating renewables into heating and cooling grids, sector coupling, and utilising waste heat are key in moving away from fossil fuels. The Campania Region (Italy), abundant in geothermal energy potential, chose a district in which to implement the GeoGRID system. This innovative setup combines a four-pipe district heating and cooling network with an Organic Rankine Cycle plant, tapping into geothermal energy from the Solfatara area. The geothermal fluid’s heat feeds the ORC evaporator and then powers the thermal network, allowing direct heating and domestic hot water supply during winter. A thorough techno-economic analysis assessed the energy potential extractable from the geothermal fluid. Crucial aspects of this study are the evaluation of the energy and environmental efficiency of the system within the renewable energy community framework. Additionally, the paper introduces a methodology applicable for assessing geothermal energy communities on a global scale. Full article

To achieve carbon neutrality and address global energy supply issues by 2050, there is active progress in the industrial sector for waste energy recovery and commercialization projects. It is necessary to consider both the energy recovery efficiency and economic feasibility based on the production volume for the resource utilization of waste energy, along with eco-friendly processing methods. In this study, a waste heat recovery system was designed to recover a large amount of thermal energy from high-temperature exhaust gases of gas engines for power generation by using biogas produced from organic waste in industrial complexes. Types and sizes of components for a waste heat recovery system that were suitable for various engine sizes depending on biogas production were designed, and the energy recovery efficiency was analyzed. The waste heat recovery system consisted of a smoke tube boiler that generated superheated steam at 161 °C under 490 kPa of pressure from the exhaust gas as the heat source, along with two economizers for heating both supply water and hot water. Heat exchangers that were suitable for three different engine sizes were configured, and their performance and energy flow were calculated. In particular, when operating two engines with a power output of 100 kW, the boiler showed the highest steam production efficiency, and the superheated steam production from high-temperature exhaust gas at 600 °C was designed to be 191 kg/h, while hot water at 58 °C was designed to be produced at 1000 kg/h. In addition, further research on the heat exchanger capacity ratio confirmed that it was within a certain range despite the difference in heat exchanger capacity and efficiency depending on the engine size. It was confirmed that the heat exchange capacity ratio of the boiler was important as an optimal-capacity design value for the entire system, as it ranged from 46% to 47% of the total heat exchanger size. Full article

The agricultural sector is one that requires and consumes enormous amounts of fresh water globally. Commercial wine production in particular uses large volumes of fresh water and, through various processes, generates significant quantities of wastewater. The wastewater produced by wineries typically exhibits elevated levels of chemical oxygen demand (COD), total suspended solids (TSS), an acidic pH, and varying salinity and nutrient contents. The overall characteristics of winery wastewater indicate that it is a potential environmental hazard if not processed and disposed of appropriately. Due to significant variations in wastewater contaminant levels among wineries, the implementation of a universally applicable, environmentally friendly, and sustainable waste management system seems practically unattainable. This study investigated the design, fabrication, and modification of a shear enhanced flotation separation (SEFS) pilot plant to be used as a primary treatment stage during winery wastewater processing. This technology combines the synergistic advantages of hydrodynamic shear, coagulation, flocculation, and dissolved air flotation. To date, there have been only limited publications on the feasibility and application of hydrodynamic shear and its potential to assist with coagulation/flocculation and flotation efficiencies specifically for winery wastewater treatment. The results obtained indicate that the SEFS pilot plant may well be able to process winery wastewater to a quality level where reuse of the water for irrigation of crops may be considered. Full article

Due to the rise in energy and water consumption, especially via water losses in water supply systems, it is imperative to reduce and eliminate such problems. Nowadays, commercial efficiency problems are present throughout the world, but in countries with a lower level of development, they have a considerable presence. Therefore, Kosovo, as such a country, has serious problems regarding commercial efficiency in the water sector. Improving performance involves sharing best practices to reduce water losses and improve collection rates. Water losses in Kosovo range from 55 to 61% of water production. Besides water losses, water utilities in Kosovo also have a low collection rate, ranging from 61% to 93% of issued invoices. Alongside these levels of non-revenue water and low collection rates, only 33.55 to 56.73% of produced water generates income. Improvement may be possible through profiling the consumption of large customers, calibrating and installing water meters with high accuracy, reading water materials with handheld devices, improving pressure management, finding illegal connections, selling a proportion of old debts, replacing old pipes with modern materials, etc. Full article

Conventional transportation systems are facing many challenges related to reducing fuel consumption, noise, and pollutants to satisfy rising environmental and economic criteria. These requirements have prompted many researchers and manufacturers in the transportation sector to look for cleaner, more efficient, and more sustainable alternatives. Powertrains based on fuel cell systems could partially or completely replace their conventional counterparts used in all modes of transport, starting from small ones, such as scooters, to large mechanisms such as commercial airplanes. Since hydrogen fuel cells (HFCs) emit only water and heat as byproducts and have higher energy conversion efficiency in comparison with other conventional systems, it has become tempting for many scholars to explore their potential for resolving the environmental and economic concerns associated with the transportation sector. This paper thoroughly reviews the principles and applications of fuel cell systems for the main transportation schemes, including scooters, bicycles, motorcycles, cars, buses, trains, and aerial vehicles. The review showed that fuel cells would soon become the powertrain of choice for most modes of transportation. For commercial long-rage airplanes, however, employing fuel cells will be limited due to the replacement of the axillary power unit (APU) in the foreseeable future. Using fuel cells to propel such large airplanes would necessitate redesigning the airplane structure to accommodate the required hydrogen tanks, which could take a bit more time. Full article

Pesticide residues, when present in agricultural wastewater, constitute a potential risk for the environment and human health. Hence, focused actions for their abatement are of high priority for both the industrial sectors and national authorities. This work evaluates the effectiveness of the photocatalytic process to decompose two frequently detected pesticides in the water effluents of the fruit industry: thiamethoxam-a neonicotinoid compound and flonicamid-a pyridine derivative. Their photocatalytic degradation and mineralization were evaluated in a lab-scale photocatalytic batch reactor under UV-A illumination with the commercial photocatalyst Evonik P25 TiO₂ by employing different experimental conditions. The complete degradation of thiamethoxam was achieved after 90 min, when the medium was adjusted to natural or alkaline pH. Flonicamid was proven to be a more recalcitrant substance and the removal efficiency reached ~50% at the same conditions, although the degradation overpassed 75% in the acidic pH medium. Overall, the pesticides’ degradation follows the photocatalytic reduction pathways, where positive charged holes and hydroxyl radicals dominate as reactive species, with complete mineralization taking place after 4 h, regardless of the pH medium. Moreover, it was deduced that the pesticides’ degradation kinetics followed the Langmuir-Hinshelwood (L-H) model, and the apparent rate constant, the initial degradation rate, as well as the L-H model parameters, were determined for both pesticides. Full article

The transportation sector is sharply shifting towards electric vehicles (EVs) to reduce environmental issues and the energy crisis. To enhance the driving range and performance of EVs, the integral parts of EVs are being developed with higher energy densities and compact structures. Traction inverters are one of the important parts of EVs which are continuously updating to higher power densities with smaller sizes. This has led to issues of high heat generation, which causes the performance degradation and failure of traction inverters. Therefore, an efficient cooling strategy needs to be proposed for the effective thermal management of traction inverters in EVs. In the present work, the magnetohydrodynamics (MHD) pump-based cooling system is developed for the thermal management of traction inverter for EVs. The cooling performance of traction inverters is investigated using a MHD pump-based cooling system with water and ferrofluid as coolants. The outlet velocity, inverter maximum temperature, and Nusselt number are numerically simulated as the cooling performance characteristics for various operating conditions of inlet velocity, magnetic field intensity, voltage, and volume fraction of ferrofluid. The coupled numerical model is developed using COMSOL Multiphysics commercial software to simulate the cooling performance of a traction inverter with an MHD pump-based cooling system under various conditions. The MHD pump improves the cooling performance of a traction inverter for ferrofluid cooling over water cooling. The cooling performance of the traction inverter improves with an increase in inlet velocity for both water and ferrofluid cooling. However, with an increase in voltage, magnetic field intensity, and volume fraction, the cooling performance of the traction inverter improves only for ferrofluid cooling. The outlet velocity, inverter maximum temperature and Nusselt number in the case of water cooling are 4.03 mm/s and 7.02 mm/s, 49.65 °C, respectively, whereas that in the case of ferrofluid cooling are 40.96 °C, 15.35, and 18.49, respectively. Further, the cooling performance improves for ferrofluid cooling at a magnetic field intensity of 0.4 T and volume fraction of 10% with outlet velocity, inverter maximum temperature, and Nusselt number approach to 12.08 mm/s, 32 °C and 21.43, respectively. Full article