Search Results (3,317)

The rising demand for energy resources and industrial goods presents significant challenges to sustainable development. Sunflower oil, commonly utilized in the food sector, biofuels, and various industrial applications, is notably affected by this demand. In Bulgaria, it serves as a primary source of vegetable fats, ranking second to butter in daily consumption. The aim of this study is to evaluate and propose methods to improve energy and resource efficiency in sunflower oil production in Bulgaria. The analysis is based on data from an energy audit conducted in 2023 at an industrial sunflower oil production facility. Reconstruction and modernization initiatives, which included the installation of high-performance, energy-efficient equipment, led to a 34% increase in energy efficiency. The findings highlight the importance of adjusting the technological parameters such as temperature, pressure, grinding level, and pressing time to reduce energy use and operational costs. Additionally, resource efficiency is improved through more effective raw material utilization and waste reduction. These strategies not only enhance the economic and environmental performance of sunflower oil production but also support sustainable development and competitiveness within the industry. The improvement reduces hexane use by approximately 2%, resulting in energy savings of 12–15 kWh/t of processed seeds and a reduction in CO₂ emissions by 3–4 kg/t, thereby improving the environmental profile of sunflower oil production. Full article

In this work, lightweight aggregates (LWAs) were prepared from an Italian red clay, pumice scraps, and spent coffee grounds. Chemical and physical characterization was first performed on the raw materials and then on the finished products. By studying the thermal behavior of the materials, the correct firing temperature was evaluated. The obtained aggregates were fired in two different modes: in a rotary kiln and in a static kiln; the influence of the firing processes on the finished products was assessed. This study can be useful for industrially scaling up this process. Firing in a rotary kiln reduced the average diameter of the aggregates (negative expansion index), resulting in a higher compressive strength and dry particle density compared to an aggregate containing only clay. The pH and electrical conductivity values address their use in agronomy without causing problems to crops, while the higher compressive strength, density, and porosity values could allow their use in construction. Full article

The growing need to improve the management of end-of-life vehicle (ELV) waste and mitigate its environmental impact is a global concern. One promising approach to enhancing the recyclability of these vehicles is leveraging synergies between the automotive and construction industries as part of a circular economy strategy. In this context, ELV waste emerges as a valuable source of secondary raw materials, enabling the development of sustainable innovations that capitalize on its physical and mechanical properties. This paper aims to develop and evaluate construction industry composites incorporating waste from ELV carpets, with a focus on maintaining or enhancing performance compared to conventional materials. To achieve this, an experimental program was designed to assess cementitious composites, specifically subfloor mortars, incorporating automotive carpet waste (ACW). The results demonstrate that, beyond the physical and mechanical properties of the developed composites, the dynamic stiffness significantly improved across all tested waste incorporation levels. This finding highlights the potential of these composites as an alternative material for impact noise insulation in flooring systems. From an academic perspective, this research advances knowledge on the application of ACW in cement-based composites for construction. In terms of managerial contributions, two key market opportunities emerge: (1) the commercial exploitation of composites produced with ELV carpet waste and (2) the development of a network of environmental service providers to ensure a stable waste supply chain for innovative and sustainable products. Both strategies contribute to reducing landfill disposal and mitigating the environmental impact of ELV waste, reinforcing the principles of the circular economy. Full article

The construction industry is a major consumer of raw materials and a significant contributor to environmental emissions. Life cycle assessment (LCA) using digital models is a valuable tool for conducting a science-based analysis to reduce these impacts. However, transferring data from environmental product declarations (EPDs) to BIM for the purpose of sustainability assessment requires significant resources for its interpretation and integration. This study is founded on a comprehensive review of the scientific literature and standards, an analysis of published digital EPDs, and a thorough evaluation of IFC (industry foundation classes), identifying twenty gaps for the automated incorporation of LCA data from construction products into BIM. The identified limitations were assessed using the digital model of a building pilot, applying simplifications to incorporate actual EPD data. This paper presents the identified barriers to the automated incorporation of digital EPDs into BIM, and proposes eleven concrete actions to improve IFC 4.3. While prior studies have analyzed the environmental data in IFC, this research is significant in two key areas. Firstly, it focuses on the direct machine interpretation of environmental information without human intervention. Secondly, it is intended to be directly applicable to a revision of the IFC standards. Full article

Using waste biomass as a raw material for the combined production of electricity and heat offers corresponding energy, economic, environmental and resource efficiency benefits. The study examines both the performance of a system for combined energy production based on the Organic Rankine Cycle (ORC) utilizing wood biomass and the market interest in its deployment within Bulgaria. Its objective is to propose a technically and economically viable solution for the recovery of waste biomass through the combined production of electricity and heat while simultaneously assessing the readiness of industrial and municipal sectors to adopt such systems. The cogeneration plant incorporates an ORC module enhanced with three additional economizers that capture residual heat from flue gases. Operating on 2 t/h of biomass, the system delivers 1156 kW of electric power and 3660 kW of thermal energy, recovering an additional 2664 kW of heat. The overall energy efficiency reaches 85%, with projected annual revenues exceeding EUR 600,000 and a reduction in carbon dioxide emissions of over 5800 t/yr. These indicators can be achieved through optimal installation and operation. When operating at a reduced load, however, the specific fuel consumption increases and the overall efficiency of the installation decreases. The marketing survey results indicate that 75% of respondents express interest in adopting such technologies, contingent upon the availability of financial incentives. The strongest demand is observed for systems with capacities up to 1000 kW. However, significant barriers remain, including high initial investment costs and uneven access to raw materials. The findings confirm that the developed system offers a technologically robust, environmentally efficient and market-relevant solution, aligned with the goals of energy independence, sustainability and the transition to a low-carbon economy. Full article

The cosmetic industry is growing at an impressive rate worldwide. In the cosmetic field, natural-origin ingredients represent the new frontier in this industry. Among the main components of cosmetics, lipids, emulsifiers, rheological modifiers, preservatives, colorants, and antioxidants can be found. These compounds form emulsions, which are among the main cosmetic formulations. An important aspect in this regard is the evaluation of emulsions’ stability over time and emulsions’ production methodology. In this paper, a comparison is made between two emulsion production technologies, the Standard and the “One-Pot” methods, through the characterization of the raw material ABWAX^® Revomul, a multifunctional wax for cosmetic use which consists of a low-melting structuring wax of vegetal origin (Rhus wax) and a natural emulsifier (Polyglyceril-3 Stearate). First, we evaluated the affinity between the wax raw materials and emollients of different chemical nature; then, we analyzed the impact of the production method on the emulsions to identify similarities and differences. ABWAX^® Revomul demonstrated a high level of effectiveness in regard to stabilizing water-in-oil emulsions. This study suggests that from an industrial point of view, the application of the two procedures allows products with different characteristics to be obtained, consequently allowing a specific method to be chosen to obtain the desired product. Full article

The use of chemical fertilizers has significantly increased crop yields but has also led to soil problems such as nutrient imbalance and salinization. In response, organic fertilizers have emerged as a crucial component for sustainable agricultural development. This study was designed to develop an easily applicable organic suspension fertilizer using peanut bran, the primary by-product of peanut oil extraction, as the main raw material. Fourier-transform infrared (FTIR) analysis revealed that 80 °C is the optimal heating temperature for forming a stable peanut-bran suspension. A comprehensive experimental investigation was conducted to evaluate the effects of different peanut bran addition levels, stabilizers, emulsifiers, and suspending agents on the stability of suspension fertilizers. The results identified the optimal suspension fertilizer formulation as comprising 20% peanut bran, 0.5% sodium bentonite, 0.1% monoglyceride, 0.2% sucrose ester, 0.02% carrageenan, and 0.3% xanthan gum. This formulation ensures good stability and fluidity of the suspension fertilizer while maintaining a low cost of 0.134 USD·kg⁻¹. The findings provide a scalable technological framework for valorizing agro-industrial waste into high-performance organic fertilizers. Full article

This study investigates the strengthening mechanisms of char in silicon dioxide thermal reduction through systematic high-temperature experiments using three char types (YQ1, CW1, HY1) characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and scanning electron microscopy. HY1 char demonstrated superior reactivity due to its highly ordered microcrystalline structure, characterized by the largest aromatic cluster size (L_a) and lowest defect ratio (I_D/I_G = 0.37), which directly correlated with enhanced reaction completeness. The carbon–silicon reaction reactivity increased progressively with temperature, achieving optimal performance at 1550 °C. Addition of Fe and Fe₂O₃ significantly accelerated the reduction process, with Fe₂O₃ exhibiting superior catalytic performance by reducing activation energy and optimizing reaction kinetics. The ferrosilicon formation mechanism proceeds through a two-stage pathway: initial char-SiO₂ reaction producing SiC and CO, followed by SiC–iron interaction generating FeSi, which catalytically promotes further reduction. These findings establish critical structure–performance relationships for char selection in industrial silicon production, where microcrystalline ordering emerges as the primary performance determinant. The identification of optimal temperature and additive conditions provides practical pathways to enhance energy efficiency and product quality in silicon metallurgy, enabling informed raw material selection and process optimization to reduce energy consumption and improve operational stability. Full article

Environmental protection has become one of the key challenges of our time. This has led to an increase in pro-environmental activities in the field of cosmetics and household chemicals, where manufacturers are increasingly trying to meet the expectations of consumers who are aware of the potential risks associated with the production of cosmetics and household chemistry products. This is one of the most important challenges of today’s industry, given that some of the raw materials still commonly used, such as surfactants, may be toxic to aquatic organisms. Many companies are choosing to use natural raw materials that have satisfactory performance properties but are also environmentally friendly. In addition, modern products are also characterized by reduced consumption of water, resources, and energy in production processes. These measures reduce the carbon footprint and reduce the amount of plastic packaging required. In the present study, seven formulations of environmentally friendly car shampoo concentrates were developed, based entirely on mixtures of bio-based surfactants. The developed formulations were tested for application on the car body surface, allowing the selection of the two best products. For these selected formulations, an in-depth physicochemical analysis was carried out, including pH, density, and viscosity measurements. Comparison of the results with commercial products available on the market was also performed. Additionally, using the multiple light scattering method, the foamability and foam stability were determined for the car shampoos developed. The results obtained indicate the very high application potential of the products under study, which combine high performance and environmental concerns. Full article

The construction sector emphasises circular economy principles that prioritise eco-design strategies, particularly the usage of secondary raw materials. The growing interest in using industrial hemp as a sustainable building material in the construction sector is driven by its versatility. Industrial hemp has been preferential in comparison to other traditional building materials due to its lower global warming impact. Claims regarding the environmental benefits of hemp-containing construction materials based on the single impact category could be misleading; therefore, life cycle assessment (LCA) studies including multiple environmental indicators should be implemented. This study aims to compare two alternative wall designs regarding their environmental impacts. The comparative LCA study for hempcrete and prefabricated walls used in residential buildings was assessed using IPCC and ReCiPe life cycle impact assessment methods. The study highlighted a significant discrepancy depending on the number of environmental indicators considered, as well as between characterised and weighted LCA results. A hempcrete wall was recognised as a slightly (13.63%) better alternative when assessed by the single-issue IPCC method, while its total burden assessed by the ReCiPe method was recognised to be significantly (2.78 times) higher. Based on the results from this case study, regulators could re-evaluate the appropriateness of reporting LCA results solely on the midpoint level, particularly when limited to a single impact indicator, while producers in the construction sector should recognise the threat of greenwashing when reporting using a single impact indicator only. Full article

Biodiesel, as one of the alternatives to fossil fuels, faces significant challenges in large-scale industrial production due to its high production costs. In addition to raw material costs, catalyst costs are also a critical factor that cannot be overlooked. This review summarizes various methods for preparing biodiesel catalysts from solid waste. These methods not only enhance the utilization rate of waste but also reduce the production costs and environmental impact of biodiesel. Finally, the limitations of waste-based catalysts and future research directions are discussed. Research indicates that solid waste can serve as a catalyst carrier or active material for biodiesel production. Methods such as high-temperature calcination, impregnation, and coprecipitation facilitate structural modifications to the catalyst and the formation of active sites. The doping of metal ions not only alters the catalyst’s acid-base properties but also forms stable metal bonds with functional groups on the carrier, thereby maintaining catalyst stability. The application of microwave-assisted and ultrasound-assisted methods reduces reaction parameters, making biodiesel production more economical and sustainable. Overall, this study provides a scientific basis for the reuse of solid waste and ecological protection, emphasizes the development potential of waste-based catalysts in biodiesel production, and offers unique insights for innovation in this field, thereby accelerating the commercialization of biodiesel. Full article

Research on raw materials for Al₂O₃-SiC-C refractory castables used in blast furnace troughs is relatively well established. However, gaps remain in both laboratory and industrial trials concerning the performance of castables incorporating SiC-modified flake graphite and alternative carbon sources. This study investigated the sintering behavior, mechanical properties, and service performance of Al₂O₃-SiC-C castables utilizing varying contents of modified flake graphite, pitch, and carbon black as carbon sources. Samples were characterized using SEM, XRD, and EDS for phase composition and microstructural morphology analysis. Key findings revealed that the thermal expansion mismatch between the SiC coating and flake graphite in SiC-modified graphite generated a microcrack-toughening effect. This effect, combined with the synergistic reinforcement from both components, enhanced the mechanical properties. The SiC modification layer improved the wettability and oxidation resistance of the flake graphite. This modified graphite further contributed to enhanced erosion resistance through mechanisms of matrix pinning and crack deflection within the microstructure. However, the microcracks induced by thermal mismatch concurrently reduced erosion resistance, resulting in an overall limited net improvement in erosion resistance attributable to the modified graphite. Specimens containing 1 wt.% modified flake graphite exhibited the optimal overall performance. During industrial trials, this formulation unexpectedly demonstrated a water reduction mechanism requiring further investigation. Full article

An oat protein isolate is an ideal raw material for producing a wide range of plant-based products. However, oat protein exhibits weak functional properties, particularly in emulsification. Casein-based ingredients are commonly employed to enhance emulsifying properties as a general practice in the food industry. pH-shifting processing is a straightforward method to partially unfold protein structures. This study modified a mixture of an oat protein isolate (OPI) and casein by combining a pH adjustment (adjusting the pH of two solutions to 12, mixing them at a 3:7 ratio, and maintaining the pH at 12 for 2 h) with an atmospheric cold plasma (ACP) treatment to improve the emulsifying properties. The results demonstrated that the ACP treatment significantly enhanced the solubility of the OPI/casein mixtures, with a maximum solubility of 82.63 ± 0.33%, while the ζ-potential values were approximately −40 mV, indicating that all the samples were fairly stable. The plasma-induced increase in surface hydrophobicity supported greater protein adsorption and redistribution at the oil/water interface. After 3 min of treatment, the interfacial pressure peaked at 8.32 mN/m. Emulsions stabilized with the modified OPI/casein mixtures also exhibited a significant droplet size reduction upon extending the ACP treatment to 3 min, decreasing from 5.364 ± 0.034 μm to 3.075 ± 0.016 μm. The resulting enhanced uniformity in droplet size distribution signified the formation of a robust interfacial film. Moreover, the ACP treatment effectively enhanced the emulsifying activity of the OPI/casein mixtures, reaching (179.65 ± 1.96 m²/g). These findings highlight the potential application value of OPI/casein mixtures in liquid dairy products. In addition, dairy products based on oat protein are more conducive to sustainable development than traditional dairy products. Full article

Aloe vera gel is a valuable raw material used in the cosmetic industry for its skin care properties. The present study analyzed the effects of the fermentation of aloe vera gel with a tea fungus kombucha, which is a symbiotic consortium of bacteria and yeast, carried out for 10 and 20 days (samples F10 and F20, respectively). The resulting ferments and unfermented gel were subjected to chromatographic analysis to determine the content of biologically active compounds. The permeability and accumulation of these compounds in pig skin were evaluated. In addition, the methods of DPPH, ABTS and the determination of intracellular free radical levels in keratinocytes (HaCaT) and fibroblasts (HDF) cell lines were used to determine antioxidant potential. The results showed a higher content of phenolic acids and flavonoids and better antioxidant properties of the ferments, especially after 20 days of fermentation. Cytotoxicity tests against HaCaT and HDF cells confirmed the absence of toxic effects; moreover, samples at the concentrations tested (mainly 10 and 25 mg/mL) showed cytoprotective effects. The analysis of enzymatic activity (collagenase, elastase and hyaluronidase) by the ELISA technique showed higher levels of inhibition for F10 and F20. The kombucha ferments also exhibited better moisturizing properties and lower levels of transepidermal water loss (TEWL), confirming their cosmetic potential. Full article