Search Results (1,004)

The travel-goods industry is an essential part of the larger travel and tourism sector, but it allegedly creates significant environmental impacts due to resource and energy consumption. This study investigates the potential of the product-service system (PSS) models to promote the transition to a sustainable travel industry in the future. It explores the drivers and barriers to PSS adoption within the luggage industry from a theoretical perspective and identifies opportunities for value creation using both consumer and luggage industry viewpoints. Four hypothetical PSS models are developed to highlight different pathways to PSS adoption, underpinned with empirical data collected via a consumer survey and semi-structured interviews with industry experts. Even though the analysis revealed shifting consumer attitudes towards servitisation concepts within the travel-goods market, at present, the widespread adoption of PSS is hindered by the fragmented nature of global supply chains and entrenched ownership values. Addressing supply chain issues in a way that empowers end-of-life systems to sustainably manage products beyond their functional obsolescence is critical. In parallel, product-oriented PSS models are more likely to increase, driven by a burgeoning resale market and supported by digital technologies, which in turn can lead to greater prospects for use-oriented PSS adoption in the long-term that would eventually promote sustainability. Full article

Food waste represents an economic, environmental, and social threat, which makes it an important subject of investigation. Food waste behavior has a crucial effect on everyone’s food security, food safety, economic growth, and the environment; hence, it requires further analysis. The article’s objective is to study the food waste reduction behavior of individual consumers and to examine factors which can explain the intention to reduce food waste. The study’s conceptual foundation is the Theory of Planned Behavior (TPB), which aims to explain the relationship between an individual’s attitudes, subjective norms, and perceived behavioral control. The paper extends the TPB by including new factors such as environmental concern, perceived ascription of responsibility, marketing addiction, moral norm, and waste preventing behavior. The data were collected via quota sampling and examined using the structural equation modeling (SEM). The study employed a sample of 369 people in Thailand. The results show that waste preventing behavior, attitude, and perceived behavioral control significantly impact the intention to reduce food waste. The subjective norm and environmental concern positively affects the attitude, which subsequently impacts the intention to reduce food waste. Marketing addiction negatively impacts perceived behavioral control and, hence, increases food waste. This research paper enlarges the understanding of the intention to minimize food waste. Moreover, it points out the implications on how consumers and the government may improve the desire to decrease food waste. Full article

The steady increase in the world’s population combined with the globally growing need for living space by each individual is leading to an ever-faster consumption of limited resources by the construction industry, particularly sand and gravel. While a consensus exists regarding the sand and gravel resource availability on a global level for long-term supply, it is important to note that local supply shortages may still occur. Thus, this study aims to identify critical aspects of both locally and globally traded construction materials by adapting the ESSENZ method, which evaluates the criticality of globally traded abiotic resources. For the specific case of the local availability of construction materials, a new indicator is introduced: The Surface Squared Driven Indicator (SSDI), which is adapted to the specific conditions of the German market. The modified ESSENZ method is applied in a case study of materials needed for maintaining the material stock of the city of Herne, Germany. The results indicate that raw materials for concrete production in Germany, such as aggregates, are expected to be sufficient in the long term, but silica sand for glass production is only guaranteed for a few decades. Concrete poses the highest supply risk due to its high material demand, with steel and concrete dominating the environmental impacts. Limitations include data availability and the exclusion of certain materials. The adapted ESSENZ method allows for the comparison of criticality results for materials traded globally and locally, offering valuable insights for decision-makers seeking to promote sustainable construction practices. Full article

Liquefied petroleum gas (LPG) is a C₃/C₄’s hydrocarbon mixture used as fuel gas, obtained through natural gas processing or crude oil refining. The Ecuadorian LPG production (~1.88 MMbbl/year) comes from the Shushufindi gas plant and the Esmeraldas refinery. However, LPG production cannot meet the Ecuadorian market demand, and over 90% of this commodity is imported. At the same time, the natural gas produced in the Amazon region is not fully valued. A significant quantity of the associated gas is flared (~100 MMscfd), representing wasted energy with a significant environmental impact. Therefore, this study aimed to develop a technical and economic assessment of the potential natural gas valuation in the Amazon region to increase LPG production. The study started with a detailed review of the associated gas produced in the Amazon region. The data were analyzed considering the geographic location of the hydrocarbon fields, molar composition, flowrates, and operational conditions. Then, a natural gas value chain visualization was proposed and technically analyzed. Finally, an economic feasibility (class V) study was conducted, considering a preliminary analysis of capital expenditure (CAPEX) and an economic balance. The outcome of this study showed that by processing 21.50 MMscfd of associated gas from the Sacha field, domestic LPG production could increase by 30.9%. The required infrastructure consists of conventional processes for natural gas processing, with an estimated CAPEX of 36.6 MMUSD. Furthermore, despite the domestic subsidies of commodities, the potential savings for the country would be 32.13 MMUSD/year, an alternative more economically viable than the current LPG imports. Thus, the investment cost will be justified. Full article

This study explores the feasibility of using an oscillating plate downstream of a cylindrical body to produce mechanical energy from a Von Kármán vortex street under sub-critical flow conditions (Re = 72,500). The study aims to quantify the impact of the plate length, its separation from the cylinder, and a machine damping factor on the power coefficient and the blade’s displacement to identify the optimal configuration. This preliminary assessment assumes that the plate oscillation is small enough to avoid changes in the vortex dynamics. This assumption allows the construction of a surrogate model using Computational Fluid Dynamics (CFD) to evaluate the effect of plate length and separation from the cylinder on the fluctuating lift forces over the plate. Later, the surrogate model, combined with varying machine damping factors, facilitates the description of the device’s dynamics through the numerical integration of an angular momentum equation. The results showed that a plate with a length of 0.52D, a separation of 5.548D from the cylinder, and a damping factor of 0.013 achieved a power coefficient of 0.147 and a perpendicular displacement of 0.226D. These results demonstrate a substantial improvement in the performance of blade-less generators. Full article

Fresh groundwater, as an essential component of global water resources and a special type of mineral wealth, has a whole set of features that affect social infrastructure, the economy and the environmental well-being of the population. At the same time, groundwater is vulnerable and limited despite its replenishable nature and vast reserves. Recently, in some countries, the practice of extracting groundwater resources by private individuals on their territory has been actively spreading, but not in all states. This is considered acceptable and is enshrined in national regulations. Uncontrolled exploitation of aquifers by small water users can affect the safety of ecosystems and the depletion of drinking groundwater reserves. In this regard, the state policy and system for regulating access to groundwater resources for all subsoil users should be based on a well-thought-out concept. This article is devoted to the organizational, economic, and regulatory issues of groundwater extraction by individuals for their own needs in the Russian Federation. A comparative analysis of the state approach to groundwater extraction by private individuals in other states (mainly in the example of Germany and China) is made. The latest trends in legislation in this area are analyzed, shortcomings in the system of state regulation of groundwater use are identified, and mechanisms for legalizing the activities of individual water users are proposed. Global groundwater regulation should be based on rationality, control, safety, protection, sustainability, and future generations’ care. Full article

Increasing the use of renewable energy sources (RES) is one of the greatest challenges faced by modern emerging and developing economies. Its effective implementation largely depends on the acceptance and involvement of consumers in the process of sustainable energy transformation. Bearing in mind the above premises, the purpose of this article is to identify the motives for the use of photovoltaic installations in Poland against the background of the share of solar energy in the structure of energy consumption in the developing economies of Central and Eastern Europe. In order to achieve this goal, the scope of the use of renewable energy sources in 11 countries of the analyzed region was determined in the course of the research; then, on the basis of the results of the survey, the motives for using solar energy by 754 Polish prosumers were identified (a statistically representative sample). The results indicate a low and relatively slow-growing use and a very different structure of RES in the surveyed economies. From the pro-consumer perspective, the decision to use solar energy is primarily influenced by economic motives, including, above all, the possibility of reducing costs and using energy also for heating. Independence factors related to the possibility of at least partial independence from energy suppliers and diversification of energy sources are also important. Ecological motivation and promotion of RES, including government incentives, are definitely less important. Full article

In hydrological modelling, it is important to consider the uncertainties related to a model’s structures and parameters when different hydrological models are used to represent a system. Therefore, an adequate analysis of daily discharge forecasts that takes into account the performance of hydrological models can assist in identifying the best extreme discharge forecasts. In this context, this study aims to evaluate the performance of three hydrological models—Lavras Simulation of Hydrology (LASH), Variable Infiltration Capacity (VIC), and Distributed Hydrological Model (MHD-INPE) in the Verde River basin. The results demonstrate that LASH and MHD can accurately simulate discharges, thereby establishing them as crucial tools for managing water resources in the study region’s basins. Moreover, these findings could serve as a cornerstone for future studies focusing on food and water security, particularly when examining their connection to climate change scenarios. Full article

This article systematizes scientific views on the problems associated with the conditions and patterns of creating a digital model of a sophisticated engineering and technical complex. The main elements of a digital model of the life cycle of an offshore oil and gas platform are considered. An interdisciplinary approach to the study of the essence of the subject space of the life cycle of an offshore oil and gas platform is substantiated on the basis of modeling the subject space of the life cycle of an offshore oil and gas platform using alternative graphs and information technologies. New concepts have been introduced into scientific circulation that reveal the essence of a digital model of the life cycle of an offshore oil and gas platform: life cycle cost, life cycle duration, and the scientific and technical level of the offshore oil and gas platform. The main provisions of the concept of the virtual life cycle of an offshore oil and gas platform are considered. Based on modeling the subject area of the life cycle of an offshore oil and gas platform by alternative graphs, is shown the relationship between the stages of the life cycle. The technology of model-based design of the virtual life cycle of an offshore oil and gas platform is proposed. The developed model of the life cycle of an offshore oil and gas platform based on the display of the life cycle by alternative graphs makes it possible to choose solutions for each stage based on criteria common to the life cycle of an offshore oil and gas platform. A cyclic procedure for managing a virtual life cycle model of an offshore oil and gas platform has been developed. The digital model of the life cycle of an offshore oil and gas platform is constantly updated following the change in physical prototypes, which increases the accuracy of decisions based on it. The application of the model in practice will significantly reduce the number of full-scale tests of everything related to the manufacture of the real material part of a platform. Full article

One drawback of biomass hydrothermal treatment (HTC) is the need of a water supply, which is especially important in the case of lignocellulosic biomass. This study has investigated the synergy resulting from co-HTC of two residual biomass materials that significantly differ in their physico-chemical compositions: (a) olive stone, OS, a hard and high-quality biomass, with low N content, whose potential to give a high heating value briquette by HTC has been proven, and (b) fresh grass pruning, GP, as it is gathered from gardens, with a high water content, moderate N fraction, and low calorific value. The work specifically focuses on the water saving that can be attained when the liquid product produced by one of them (grass, with 80% of moisture) can supply part of the water needed by the other (olive stone) when both are subjected to HTC simultaneously. It was found that, when instead of water, an additional amount of fresh GP is added (in particular 40 out of 110 g of water was provided by 54 g of GP), and a more basic processing water is obtained (pH of co-HTC increased by 40%, in relation of single OS processes). This in turn did not have a remarkable effect on OS final SY at any of the two temperatures studied (200 and 220 °C), not on the C densification. Other features such as N content of resulting OS hydrochars showed a rise in the case of hybrid processes, from 0.2% to 3.3%. Other features that were affected on OS HTC products because of the presence of the GP in co-HTC were the HC surface structure, hydrophobicity, and the presence of surface functionalities and their thermal stability towards pyrolysis; processing water also showed changes on mineral content when both biomasses there blended. Proving that a biomass like OS can be hydrothermally treated by a hybrid process involving less water, without being detrimental in terms of final SY and energy densification, can open a field of research aimed to make HTC processes more efficient in terms of hydric balance. Full article

Low concentrations of fluoride (F⁻) in drinking water are beneficial for oral health, but the natural occurrence of high F⁻ content has been reported in various groundwater sources, posing a continuous ingestion threat to humans. The utilization of biochar (BC) produced from residual biomass has emerged as a technically, economically, and environmentally sustainable alternative for fluoride removal through adsorption. Therefore, this study aimed to investigate the physicochemical characteristics of BC derived from coffee grounds and the influence of various factors on the adsorption process of F⁻ in aqueous media, including pH, adsorbent dosage, contact time, temperature, and initial F⁻ concentration. The BC exhibited a surface area of 12.94 m²·g⁻¹ and a pore volume of 0.0349 cm³·g⁻¹. The adsorption process was strongly pH dependent, demonstrating a significant decline in performance as pH increased from 2.0 onwards. The majority of F⁻ removal occurred within the first 5 min, reaching adsorption equilibrium after 1 h of testing, regardless of the initial F⁻ concentration employed. The data fitting to the Webber–Morris model indicated a two-step adsorption process on BC, with the first step being external surface sorption and the second step being intra-articular diffusion. The process was determined to be endergonic, and the data satisfactorily matched both the Freundlich and Langmuir models, with a q_m of 0.53 mg·L⁻¹ (T = 55 °C), indicating the predominance of physisorption. The findings suggest the potential of coffee grounds for BC production; nevertheless, surface structure modifications are necessary to enhance F⁻ affinity and subsequently improve adsorption capacity. Full article

Bulgaria is famous for its oil-bearing rose. R. damascena Mill. and R. alba L. are mainly cultivated in the country, but a recent survey of industrial plantations in 2020 revealed that R. centifolia L. and hybrids of R. damascena Mill. X R. gallica L. are also common in the rose valley. Although their essential oil cannot be compared in quality with the classic, these species are preferred by farmers with high yields of flowers and resistance to diseases and pests. All these roses are also used to produce rose water and extracts. The aim of this investigation was to compare the yield and chromatographic fingerprints of seven rose oils and hydrosols produced in Bulgaria. The quantitative composition of the main components of the oils was compared with the norms of the world standards. Our study showed that the yield of essential oil from these roses was in the range of 0.015–0.048%. The main group in the chemical composition is terpene alcohols, which vary in range: geraniol (15.85–34.02%), citronellol (6.70–28.72%), and nerol (5.80–11.90%) but with a different ratio. Hydrocarbons are represented by saturated aliphatic homologs with an odd number of carbon atoms, the main ones being nonadecane (8.10–22.67%), heneicosane (4.37–10.21%), heptadecane (1.07–2.98%), and triclosan (0.81–5.90%). In contrast, the chemical profile of the hydrosols was performed using phenylethyl alcohol (27.45–69.88%), geraniol (13.72–28.67%), and citronelol+nerol (4.56–17.37%). The results show that the presence of plantations with a genotype different from that of R. damascena implies differences in the quality of rose oils and hydrosols. This determines their properties of use. Full article

In recent years, as a result of intensive urbanisation, a significant increase in the surface of impermeable areas has been observed, which results in changes in the hydrological cycle of catchments. In order to counteract these changes, low-impact development (LID) solutions are increasingly being implemented in urban catchments, including bioretention systems. Taking this into account, a new bioretention drainage channel (BRC) was designed, whose main task is retention, infiltration, and pre-treatment of rainwater. The pilot laboratory tests carried out on two BRC prototypes (K1 and K2) showed that the average rate of reduction of mineral-suspended solids from rainwater was 69% and 57%, respectively, for K1 and K2. Analysing the results of the research, it was found that the bioretention drainage channel is characterised by very high efficiency in removing petroleum hydrocarbons from rainwater, and the reduction rate of these pollutants for both the K1 and K2 channels was close to 100%. In turn, hydrodynamic studies carried out on the model of the urban catchment showed that the implementation of BRCs will reduce the peak runoff by more than 82%, and the maximum flow in the sewage network by 83%. Full article

The current study investigated the performance of a moving bed biofilm reactor (MBBR), when adding 3D-printed biocarriers fabricated with 13X and bentonite (MBBR 3D), when using K1 commercial biocarriers (MBBR K1) and when not adding biocarriers at all (control MBBR). For the evaluation of the MBBR efficiency, various physicochemical parameters were measured, while biofilm extracted from the biocarriers was evaluated. The findings suggest that there is an optimal biodegradation of the organic load in all MBBR units. The nitrification and denitrification processes were improved in MBBR 3D as compared to the control MBBR and MBBR K1. The dry mass of the biofilm in the 3D-printed biocarriers was two orders of magnitude larger than in the K1 biocarriers. Moreover, in the K1 biocarriers the mass of the biofilm varied in relation to time, since it could not be protected inside the holes, something that did not happen with the 3D-printed biocarriers. Finally, it was found, mostly in MBBR 3D and less in MBBR K1, that the growth of nitrifying bacteria and heterotrophs inside the units increased the biomass production in the form of soluble microbial products, which in turn favored the adhesion of biomass on the surface of biocarriers. Full article

The present study contributes to the ongoing debate on environmental sustainability and the low-carbon agenda in terms of an analysis of a relatively new international association, the Shanghai Cooperation Organization (SCO). Based on panel data from SCO countries from 2000 to 2020, the hypothesis of the existence of the Environmental Kuznets Curve (EKC) was tested. The results showed the validity of the EKC hypothesis for the SCO countries; in particular, the gross domestic product and natural resource rents have a connection with greenhouse gas (GHG) emissions, while trade openness, foreign direct investment and the use of renewable energy sources reduce GHG emissions in the long term. It was also found that the effect of economic growth on GHG emissions in the long term in the SCO countries has the form of an inverse N-curve. Based on the analysis performed, recommendations are offered to improve energy policy in the field of alternative energy sources, natural resources—rents on them, openness to foreign markets and attracting foreign investment. Full article