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This article focuses on the development of a conceptual framework guiding the adoption of biogas technology in selected rural areas of the Limpopo province. The theoretical framing of the study emanated from the critical evaluation of models and work that privileged the technical design and optimisation of a biogas system over the adoption of the technology at the household level. Based on the empirical evidence, and using logistic regression analysis, the study highlighted that determinants of biogas technology adoption in communities are complex, context-dependent and spatially varied. Hence, the policy of biogas adoption should be tailored based on the principle of fit-for-purpose, instead of using existing unimodal approaches for all settings. Based on the findings, the study developed a robust conceptual framework that harnesses the relationships between the influencing variables that can enhance the adoption of biogas technology. Full article

Thirty crude oils, belonging to light, medium, heavy, and extra heavy, light sulfur, and high sulfur have been characterized and compatibility indices defined. Nine crude oil compatibility indices have been employed to evaluate the compatibility of crude blends from the thirty individual crude oils. Intercriteria analysis revealed the relations between the different compatibility indices, and the different petroleum properties. Tetra-plot was employed to model crude blend compatibility. The ratio of solubility blending number to insolubility number was found to best describe the desalting efficiency, and therefore could be considered as the compatible index that best models the crude oil blend compatibility. Density of crude oil and the n-heptane dilution test seem to be sufficient to model, and predict the compatibility of crude blends. Full article

Biofuels derived from renewable plant materials are considered promising alternative fuels to decrease emissions of ICEs. This study aimed to justify the possibility of using vegetable oils of different sources as a 10% additive in blended biofuel for diesel engines of agricultural machinery and commercial vehicles. Seven different vegetable oils were investigated. Experiments have been performed by fueling a diesel engine with blended biofuels of 90% petroleum diesel fuel and 10% vegetable oil. In the maximum power and maximum torque modes, the brake power drop was no more than 1.5%, and the brake-specific fuel consumption increase was less than 4.3%; NOx emissions were reduced by up to 8.3%, exhaust smoke—up to 37.5%, CO—up to 20.0%, and unburned HC—up to 27.9%. In the operating modes of the European 13-mode steady-state test cycle, the integral specific emissions of HC decreased by up to 30.0%, integral specific emissions of CO—up to 15.0%, and integral specific emissions of NOx—up to 16.0%. The results obtained show the feasibility and rationality of using the investigated vegetable oils as a 10% additive in blended biofuel for diesel engines of agricultural machinery and commercial vehicles. Full article

One of the main hazards occurring in post-mining areas is the uncontrolled migration of gases to the surface, which may pose a serious threat to life and health. These gases are mainly methane and carbon dioxide, in smaller amounts ethane and higher hydrocarbons, carbon oxide, hydrogen sulfide, and radon. Methane migrating into the lower levels of buildings, garages, cable ducts, and sewage systems reaching the concentrations of above 5% may cause an explosion hazard. The concentration of carbon dioxide over 4% also represents a serious threat to life. Moreover, carbon dioxide and methane, emitted into the atmosphere, constitute a considerable source of greenhouse gases. The methane could be utilized, yet it is necessary to develop effective capture and purification methods with the first step of determination being its migration routes. The paper presents the application of numerical modelling with the use of TOUGHv2.0 software, which enabled effective simulation of the multiphase flow, applying adsorption and diffusion phenomena. The results of gas migration modelling were compared to the outcomes of geological tests, and the obtained results were satisfying. It was observed that both geological investigation and computer simulations are proper tools for investigation of the phenomenon of gas migration and identification of gas hazard areas on the surface, constituting the basis for development of effective methane capture methods for further application. Full article

Aluminium is a metal of high economic importance for the European Union (EU), presenting unique properties (e.g., light weight and high corrosion resistance) and with applications in important sectors (e.g., transportation, construction and packaging). It is also known for its high recyclability potential, but relevant losses occur in its life cycle, compromising the amount of aluminium available for secondary production. A novel methodology that allows the identification of these losses and their impact on the aluminium flows in society is the MaTrace model. The objective of this article is to perform a dMFA of the secondary production of aluminium in the EU technosphere using the modified version of MaTrace, in order to estimate flows of the metal embedded in 12 product categories. Twelve scenarios were built in order to assess the impact of changes in policies, demand and technology. The flows were forecasted for a period of 25 years, starting in 2018. The results of the baseline scenario show that after 25 years, 24% of the initial material remains in use, 4% is hoarded by users, 10% has been exported and 61% has been physically lost. The main contributor to the losses is the non-selective collection of end-of-life products. The results of the different scenarios show that by increasing the collection-to-recycling rates of the 12 product categories, the aluminium that stays in use increase up to 32.8%, reaffirming that one way to keep the material in use is to improve the collection-to-recycling schemes in the EU. Full article

Inter-criteria analysis was employed in VGO samples having a saturate content between 0.8 and 93.1 wt.% to define the statistically significant relations between physicochemical properties, empirical structural models and vacuum gas oil compositional information. The use of a logistic function and employment of a non-linear least squares method along with the aromatic ring index allowed for our newly developed correlation to accurately predict the saturate content of VGOs. The empirical models developed in this study can be used not only for obtaining the valuable structural information necessary to predict the behavior of VGOs in the conversion processes but can also be utilized to detect incorrectly performed SARA analyses. This work confirms the possibility of predicting the contents of VGO compounds from physicochemical properties and empirical models. Full article

Hydrologic alternation of river systems is an essential factor of human activity. Cascade-dammed waters are characterized by the disturbed outflow of material from the catchment. Changes in sediment, dissolved load and nutrient balance are among the base indicators of water resource monitoring. This research was based on the use of hydrological and water quality data (1984–2017) and the Indicators of Hydrologic Alteration (IHA) method to determine the influence of river regime changes on downstream transfer continuity of sediments and nutrients in the example of the Lower Brda river cascade dams (Poland). Two types of regimes were used: hydropeaking (1984–2000) and run–of–river (2001–2017). Using the IHA method and water quality data, a qualitative and quantitative relationship were demonstrated between changes of regime operation and sediment and nutrient balance. The use of sites above and below the cascade made it possible to determine sediment, dissolved load, and nutrient trapping and removing processes. Studies have shown that changes in operation regime influenced the supply chain and continuity of sediment and nutrient transport in cascade-dammed rivers. The conducted research showed that sustainable management of sediment and nutrient in the alternated catchment helps achieve good ecological status of the water. Full article

Thirty-one batches of commercial charcoal from various regions of Poland and Germany were tested for the presence of 20 toxic elements and polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry (GC-MS). Elements that are toxic to living organisms were determined using atomic absorption spectroscopy (AAS). They were classified as elements representing a very high degree of hazard (As, Cd, Cu, Hg, and Pb), high degree of hazard (Zn, Ba, Cr, Mn, and Mo), moderate degree of hazard (Co, Ni, Sn, and Te), and a low degree of hazard for living organisms and the environment (Ag, Bi, Ce, Se, Sr, and Zr). In regard to the most toxic elements, the highest concentration in the whole tested material was recorded for Cu. In addition, considerable amounts of Ba, Mn, and Sr, i.e., elements representing a high or moderate degree of hazard, were found in the tested charcoals. Moreover, all charcoals contained a wide range of PAHs, from naphthalene to benzo(ghi)perylene, with concentrations in a range between 12.55 and 3554.11 ng/g charcoal. In total, 25 unsubstituted PAHs were identified in the charcoal extracts. PAHs distributions were dominated by five-ring PAHs. The results indicate high carcinogenicity with ∑PAHcarc/∑PAHtot close to 1, as well as high TEQ and MEQ values. Thus, prolonged exposure to charcoal and charcoal dust might cause serious health problems. This applies to employees actively involved in the production and transport of charcoal and, to a lesser extent, users of this fuel. Full article

The concept of eco-innovation addresses a reduction in negative environmental impacts and the more efficient use of resources. As an integral part of eco-innovation, green technologies are receiving increasing attention due to growing environmental concerns. Patent data are one of the measures of the output of technological eco-innovation. However, understanding the patenting of eco-innovation comes with challenges. The aim of this study is to measure the output of eco-innovation and to analyse the trends in green technologies based on environment-related patents in the world’s leading countries from 2000 to 2017. For this research, a range of data collection techniques based on patent data from leading countries such as China, Korea, Japan, United States and Germany were employed. The study provides a comprehensive overview of changes and trends in the development of environmental technologies using different domains. In particular, significant progress has been made in the areas of environmental technologies and climate change mitigation technologies related to energy generation, transmission or distribution. These technologies are closely linked to international environmental policies such as climate change mitigation and green industry transformation. The study also contributes to the literature on measuring the output of eco-innovation. Full article

Major benefits and constraints related to mineral extraction within the EU have been identified on the examples of selected critical raw materials’ deposits. Analyzed case studies include the following ore deposits: Myszków Mo-W-Cu (Poland), Juomasuo Au-Co (Finland), S. Pedro das Águias W-Sn (Portugal), Penouta Nb-Ta-Sn (Spain), Norra Kärr REEs (Sweden) and Trælen graphite (Norway). They represent different stages of development, from the early/grassroot exploration stage, through advanced exploration and active mining, up to reopening of abandoned mines, and refer to different problems and constraints related to the possibility of exploitation commencement. The multi-criteria analysis of the cases has included geological and economic factors as well as environmental, land use, social acceptance and infrastructure factors. These factors, in terms of cost and benefit analysis, have been considered at three levels: local, country and EU levels. The analyzed cases indicated the major obstacles that occur in different stages of deposit development and need to be overcome in order to enable a new deposit exploitation commencement. These are environmental (Juomasuo and Myszków), spatial (Juomasuo) as well as social constraints (Norra Kärr, Juomasuo). In the analyzed cases, the most important constraints related to future deposit extraction occur primarily at a local level, while some important benefits are identified mainly at the country and the EU levels. These major benefits are related to securing long-term supplies for the national industries and strategically important EU industry sectors. Full article

Water erosion is one of the major factors of soil degradation in the world. Various methods have been developed to prevent soil erosion. One of them is the use of anti-erosion belts on slopes, but it has both positive and negative effects. In order to minimize the negative effects, this study proposes the use of perennial grass in place of the most commonly used trees and shrubs. The paper presents studies on the erosion control effectiveness of a strip planted with Miscanthus x giganteus, established on a loess slope. Surface runoff of water and its constituents and erosion damage was studied on the experimental plot with a separate anti-erosion belt and the control plot. Obtained results indicate the anti-erosion efficiency of the established strip in the context of soil protection from water erosion and surface water protection from pollution, although, in the first years of vegetation, miscanthus has not yet reached the stage of full development. The average surface water runoff relating to precipitation causing the erosive event was 17.1% higher in the control plot than in the experimental plot. The volume of erosion damage in the form of rill erosion was 89.3% higher in the control plot. On the other hand, the volume of erosion damages in surface erosion and patches of deposited silts was lower by 14.7% and 21.6%, respectively. Soil losses from the control plot were 29% higher than those from the experimental plot. Dissolved plant nutrient runoff was also higher from the control plot by: 33.4% N-Ntot, 31.3% N-NH₄, 42.7% N-NO₃, 21.6% N-NO₂, 22.9% P-Ptot, 24.1% K. Full article

The development of mineral resources in the Arctic territories is one of the priorities of the state policy of Russia. This endeavor requires modern technologies, high-quality personnel, and a large number of labor resources. However, the regions of the Arctic are characterized by difficult working and living conditions, which makes them unattractive to the working population. The research objectives were to study the importance of Arctic mineral resources for the Russian economy, the Arctic mineral resource potential, and the migration attractiveness of Arctic regions. The migration processes in these locations were analyzed and modeled using a new econometric tool—complex-valued regression models. The authors assume that the attractiveness of the Arctic regions is determined by the level of their social and economic development and can be assessed using a number of indicators. A comparative analysis of four regions that are entirely in the Arctic zone of the Russian Federation was carried out based on the calculation of integral indicators of the social and economic attractiveness of these territories. Forecasting migration growth using the proposed complex-valued models produced better results than simple trend extrapolation. The authors conclude that complex-valued economic models can be successfully used to forecast migration processes in the Arctic regions of Russia. Understanding and predicting migration processes in the Arctic will make it possible to develop recommendations for attracting labor resources to the region, which will contribute to the successful development of its resource potential. The methodology of this study includes desk studies, a graphical method, arithmetic calculations, correlation analysis, statistical analysis, and the methods of the complex-valued economy. Full article

The economic and strategic importance of tungsten is widely recognized, but several concerns exist on its stable future supply. Portugal is one of the main tungsten producers in Europe, having generated ≈121 kt of contained tungsten in mineral concentrates from 1910 to 2020, i.e., ≈3.3% of the global production documented for the same time period. Since the early nineties, tungsten mining in Portugal is confined to the Panasqueira deposit which accounts for 79% of the country reserves (≈5.4 kt). However, according to the performed Generalized Verhulst and Richards curve-fitting forecasts, there is a significant future potential for increasing production in Portugal due to the low (<2%) depletion rates of the remaining known tungsten resources (≈141 kt). This projected growth is not necessarily guaranteed, depending on many unpredictable economic, technological, and political factors, besides appropriate social consents. Even so, a prudent land-use planning oriented to long-term needs should avoid the sterilization of the most relevant tungsten resources so far identified in the country. These are resources of “public importance”, as objectively demonstrated with a weighed multi-dimensional (geological, economic, environmental, and social) approach. Safeguarding the access to these resources does not implicate more than ≈6% of the Portugal mainland territory. The joint interpretation of results independently gathered for tungsten production forecasts and for the definition of areas hosting tungsten resources of public importance, provides additional support to political decisions on the urgent need to reconcile mineral exploration surveys and mining with other land uses. Full article

The improvement in valorisation of industrial minerals and rocks in Serbia is related to improvement of legislation, and to adoption of best possible techniques for geological exploration and estimation of resources/reserves. Therefore, we analyzed the actual practice in the field of geological exploration which has not changed significantly in the last 30 years, as well as legislation related to the mining industry and access to land. The improvement of legislation mostly depends on the state authorities. Contrary to that, the enhancement of geological exploration methodology should be the issue of experts working in that area of the mining industry but is also very much related to the existing legislation. Serbia still has very strictly prescribed procedures, which are generally good; however, it is an overly complicated and restrictive system for performing geological exploration and evaluation of mineral deposits. The most important improvements in legislation in the last twenty years are presented and discussed, as well as problems that still need to be solved and solutions found to fully understand the potential of industrial minerals and rocks in Serbia. Full article

The provision of detailed information on the impact of potential fluvial floods on urban population health, quantifying the impact magnitude and supplying the location of areas of the highest risk to human health, is an important step towards (a) improvement of sustainable measures to minimise the impact of floods, e.g., by including flood risk as a design parameter for urban planning, and (b) increase public awareness of flood risks. The three new measures of the impact of floods on the urban population have been proposed, considering both deterministic and stochastic aspects. The impact was determined in relation to the building’s function, the number of residents, the probability of flood occurrence and the likely floodwater inundation level. The building capacity concept was introduced to model population data at the building level. Its proposed estimation method, an offshoot of the volumetric method, has proved to be successful in the challenging study area, characterised by a high diversity of buildings in terms of their function, size and density. The results show that 2.35% of buildings and over 122,000 people may be affected by 500-year flooding. However, the foreseen magnitude of flood impact on human health is moderate, i.e., on average ten persons per residential building over the 80% of flood risk zones. Such results are attributed to the low inundation depth, i.e., below 1 m. Full article

The changes in climate, which are associated with the emission of anthropogenic greenhouse gases, have been widely discussed by scientists and specialists during the last few decades. The promising way to reduce CO₂ emission is to implement CC(U)S technologies (carbon capture, (utilization) and storage). However, CC(U)S initiatives are challenging that prevent their widespread adoption. The main purpose of the research is to prove that CC(U)S should be considered broader than a way to reduce emission, and such initiatives could lead to various public effects and create long-term “combined value” for the industry and wider society; all of these should be considered when making decisions on CC(U)S implementation. The results of the research are presented by highlighting bi-directional interaction between CC(U)S and society, including public acceptance and public effects; identifying the possible positive and negative impact of CC(U)S initiatives on the public; developing a system of indicators for assessing the public effects of CC(U)S; proposing the framework for a value at stake analysis (VAS) of CC(U)S initiatives in order to reveal and assess their “combined value”. The methodology of this study includes desk studies, decomposition technique, environment (E), health (H) and safety (S) (EHS) approach, classification techniques, and VAS analysis. Full article

While the successful reclamation of coal post-mining land sites in Indonesia has been evaluated, no cost-benefit analysis has been carried out on the reclamation of mined land, and the impact of the reclamation work has not been determined. The results of this case study indicate that reclamation work is not an emission-free process, but that the benefits delivered from this work are considerable. It was found that the emissions involved at the coal mined reclamation in Indonesia were 25.4–26.6 t-CO₂/ha, with topsoil management and land preparation contributing over 98% of the total emissions (9.5 t-CO₂/ha and 16 t-CO₂/ha, respectively). The ability of the trees on the reclaimed land to absorb CO₂ emissions was calculated to be 26.4 t-CO₂/ha, with the amount of oxygen produced calculated to be as much as 143 t-O₂/ha of oxygen. The economic value of the ecosystem services delivered by reclamation was over USD 27,750/ha. This is higher than the USD 8642–9417/ha cost of establishing the reclamation work. Improvements to reclamation work could be designed mining and reclamation plans with attention paid to reducing fuel consumption, and therefore, reducing CO₂ emissions. Furthermore, law enforcement and transparency, human resource development, and community participation are strongly required. Full article

This is the first report about flaxseed protein hydrolysates applied as media supplements in CHO cell culture. The hydrolysates were produced by three separate enzymatic digestions of proteins isolated from flaxseed oil cake. The enzymes used were Alcalase, Neutrase, and Protamex, and the most efficient hydrolysis was achieved with Alcalase. The three hydrolysates were first tested as a partial substitute for serum in basal media in order to evaluate their effects on the adherent IgG-producing CHO cell line. The cells that grew in such media reached higher density than the cells in media supplemented with serum only. Consequently, the increased cell number improved the final IgG titer. In the next experiment, the impact of hydrolysates was evaluated in suspension CHO culture adapted to chemically defined media. In this preliminary investigation, the cells showed no response to the hydrolysate addition concerning the growth rate and productivity. Despite this outcome, we speculate that low molecular mass components in the hydrolysates, besides nutritive, may have a cell-protective function. Full article

The growth of the lithium-ion battery industry requires a secure supply of raw materials and appropriate end-of-life management of batteries. In almost five years, global cobalt consumption has increased by nearly 30%, driven mainly by rechargeable batteries. Consequently, several risks have been identified for cobalt, in particular the growing demand for electric vehicles, which could exceed current production. Therefore, research into the recovery of this critical metal, from industrial or urban waste, is particularly important in the years to come. In this study, cobalt is recovered from a lithium-ion battery leachate in hydroxide form. The thermodynamic simulations performed with Visual Minteq showed that it was possible to recover 99.8% of cobalt (II) hydroxide at 25 °C. Based on these results, experiments were conducted to validate the hypotheses put forward and to compare the results obtained with the simulations performed. Experimentally, several operating parameters were studied to determine the optimal conditions for cobalt recovery, in terms of yield, filterability, and selectivity. Results obtained in a batch reactor allowed the determination of the temperature conditions to be applied in continuous reactor. The cobalt (II) hydroxide precipitation in continuous reactor was carried out under different pH conditions. It was then possible to determine the optimal conditions for cobalt recovery in terms of yield and filterability. Results showed that working at pH 9 would effectively meet the desired criteria. Indeed, cobalt recovery is close to 100% and filtration flow rate is three times higher. Results obtained allow a better understanding of cobalt (II) hydroxide precipitation. Full article