Search Results (106)

Faced with the depletion of fossil resources and the need to promote a circular economy, lignocellulosic biomass represents a solution for energy transition and bioeconomy. However, wood sawdust, which contains bioactive compounds (secondary metabolites), is often burned in the open by many sawmills. This study aims to valorize Framiré wood sawdust by extracting its secondary metabolites through maceration and infusion, then converting the depleted residue into combustible briquettes. The yellowness index of the extracts ranged from 73.490 ± 0.021 (maceration) to 81.720 ± 0.014 (infusion). The total phenolic content varied from 0.097 ± 0.001 to 0.63 ± 0.049 gGAE/100 g dry matter for maceration and infusion, respectively. The extraction of bioactive compounds did not significantly affect the energy or mechanical properties of the fuels. Their higher heating value ranged from 26,153 ± 92 to 26,201 ± 90 kJ/kg for fuels with and without secondary metabolites, respectively. The Shock Resistance Index ranged from 139.33 ± 7.51% (without metabolites) to 153.00 ± 5.20% (with metabolites). A significant difference was observed in the specific consumption of the fuels, decreasing from 1.400 ± 0.100 to 0.861 ± 0.001 kg/L for fuels without and with secondary metabolites, respectively. These results open promising prospects, particularly for the use of Framiré extracts to develop flame-retardant products for wood and its derivatives. Full article

The cement industry is at the core of global economic and infrastructure development accounts, but it also accounts for 7% to 9% of total emitting CO₂ For Pakistan, it is a major consumer of coal, emitting 8.9 Mt of CO₂ annually, resulting in nearly 49% of the country’s coal While several strategic initiatives are being adopted to lower conventional fuel consumption in the cement sector such as an increased shift towards solar energy deployment, initiating the shift from coal to alternate materials, but a well-regulated alternative fuel policy framework across cement production processes remains a clear gap in the industry’s decarbonization efforts. Given this challenge, this study conducts a scenario-informed quantitative evaluation using the Low-Emission Analysis Platform (LEAP) to explore the decarbonization potential of fuel switching in Pakistan’s cement industry, aligning it with NDC, Net-zero, and energy transition targets. The results reveal that swapping out coal and petroleum coke for cleaner alternatives would be necessary for reducing emissions by 13.5 Mt under the NDC scenario and 17.1 Mt for net-zero by 2050. However, achieving these targets requires a well-defined policy framework, regulatory support for Refuse-Derived Fuel (RDF) and Tire-Derived Fuel (TFD), building a sustainable biomass chain and quality control units, and capital investment in cleaner fuels. Full article

The study presents a comprehensive assessment of greenhouse gas (GHG) emissions and the carbon footprint (CF) of high-percentage spirit production in a Polish distillery. The analysis followed the GHG Protocol and ISO 14067:2018 standards, covering direct and indirect emissions across three Scopes. Using life cycle assessment (LCA) with a gate-to-gate boundary, emissions were across key technological processes. Verified operational data for 2022–2024 included detailed records of energy and fuel consumption. Electricity use was identified as the dominant emission source, accounting for 70–93% of total GHG emissions, followed by natural gas and transport fuels. The integration of renewable energy sources, including biomass and photovoltaic installations, resulted in a significant decrease in GHG emissions. The average carbon footprint of spirit production declined from 1.02 kg CO_2eq/L in 2022 to 0.12–0.15 kg CO_2eq/L in 2023–2024, representing an over 85% reduction in emission intensity. Production increased, but the company implemented better practices, including the use of biomass and photovoltaics as energy sources, which translated into a reduction in its carbon footprint. Scenario analysis showed that implementing the replacement of conventional fuels with renewables could lower total GHG emissions by up to 35%. The results confirm that renewable energy implementation and energy-efficiency improvements are effective decarbonization strategies for the spirits industry, supporting compliance with European Green Deal objectives and the transition toward climate-neutral production. Full article

Renewable energy expansion requires cost-effective strategies to integrate underutilized biomass resources into energy systems. In Australia, forest residues represent a significant but largely untapped feedstock that could contribute to a more diversified energy portfolio. This study presents an integrated geospatial and optimization decision-support model designed to minimize the total cost of forest biomass-to-bioenergy supply chains through optimal facility selection and network design. The model combined geographic information systems with mixed-integer linear programming to identify the optimal candidate facility sites based on spatial constraints, biomass availability and infrastructure proximity. These inputs then informed an optimization framework that determined the number, size, and geographical distribution of bioenergy plants. The model was applied to a case study in Queensland, Australia, evaluating two strategic scenarios: (i) a biomass-driven approach that maximizes the use of forest residues; (ii) an energydriven approach that aligns facilities with regional energy consumption patterns. Results indicated that increasing the minimum facility size reduced overall costs by capitalizing on economies of scale. Biomass collection accounted for 81%–83% of total supply chain costs (excluding capital installation), emphasizing the need for logistically efficient sourcing strategies. Furthermore, the system exhibited high sensitivity to transportation distance and biomass availability; energy demands exceeding 400 MW resulted in sharply escalating transport expenses. This study provides a scalable, data-driven framework for the strategic planning of forest-based bioenergy systems. It offers actionable insights for policymakers and industry stakeholders to support the development of robust, cost-effective, and sustainable bioenergy supply chains in Australia and other regions with similar biomass resources. Full article

From September 8th to 12th, 2024, the 19th SDEWES Conference on Sustainable Development of Energy, Water, and Environment Systems was successfully held in Rome. This event drew 700 researchers, scientists, and practitioners from 62 nations across six continents, with 570 participating in person and another 130 joining virtually. A total of seven papers were selected to be published in Energies, and the corresponding literature published in the most recent year is here reviewed. The main topics of the selected papers regard the adoption of district heating and cooling and their integration with renewable energies (such as geothermal or solar, the use of innovative bifacial PV panels, the use of biomass energy for the bio-synthetic natural gas production, the short-term electric load forecasting for industrial applications, and others. The reviewed papers show that several energy measures can be addressed to reach the decarbonization goals of 2050 and that the scientific community continues to find novel, sustainable, and efficient methods for the reduction in energy consumption and related CO₂ emissions. Full article

Human activities undoubtedly increase greenhouse gases (GHG), negatively influencing global climate change. The building and construction sector uses at least 40% of the total energy consumption and produces the same percentage of GHG emissions. Therefore, the development of sustainable building materials is a crucial key factor for environmental protection. The study contributes to the development of bio-based façade materials using available raw biomass like wheat straw, grey alder, and softwood (a mix of spruce and pine), to promote reduced emissions of CO₂. Two technologies were used to produce high-density particleboards based on (1) steam explosion treatment and (2) the addition of bio-based suberinic acids as a binder. In addition to the biomass species and board type, the influence of conventional and mold hot-pressing was investigated on produced board properties: density, thickness swelling, modules of rupture and elasticity in bending, and internal bonding. The obtained particleboards demonstrate significant differences in terms of the tested properties depending on all variable factors. The best performance, in terms of physical–mechanical properties, was achieved by the conventionally hot-pressed board of steam-exploded grey alder particles, being influenced by the highest density (1380 kg/m³). Mold hot-pressing in most cases resulted in decreased performance of obtained boards. Full article

This review systematically examines the critical mechanisms and process optimization strategies of algal–bacterial granular sludge (ABGS) technology in wastewater treatment. The key findings highlight the following: (1) enhanced pollutant removal—ABGS achieves >90% COD removal, >80% total nitrogen elimination via nitrification–denitrification coupling, and 70–95% phosphorus uptake through polyphosphate-accumulating organisms (PAOs), with simultaneous adsorption of heavy metals (e.g., Cu²⁺, Pb²⁺) via EPS binding; (2) energy-saving advantages—microalgal oxygen production reduces aeration energy consumption by 30–50% compared to conventional activated sludge, while the granular stability maintains >85% biomass retention under hydraulic shocks; (3) AI-driven optimization—machine learning models enable real-time prediction of nutrient removal efficiency (±5% error) by correlating microbial composition (e.g., Nitrosomonas abundance) with operational parameters (DO: 2–4 mg/L, pH: 7.5–8.5). This review further identifies EPS-mediated microbial co-aggregation and Chlorella–Pseudomonas cross-feeding as pivotal for system resilience. These advances position ABGS as a sustainable solution for low-carbon wastewater treatment, although challenges persist in scaling photobioreactors and maintaining symbiosis under fluctuating industrial loads. Full article

The lactic acid (LA) production from corn stover using Lewis acid catalysts was optimized. Initially, an equimolar mixture of Al(III)/Sn(II) was used as a catalytic system at 190 °C with 5 wt% biomass. Increasing the catalyst concentration led to higher LA production, showing the optimal results at 16 mM. A low catalyst concentration mainly produced furfural and HMF, dehydration products from the corn stover sugars. Higher catalyst concentration increased LA yield but also produced the degradation of the glucose dehydration products into levulinic and formic acids, reducing LA selectivity. Al(III) was essential for LA formation, while Sn(II) was less effective due to its lower solubility, shown by the presence of Sn(II) in the solid residue after treatments. A total of 16 mM Al(III) yielded the highest LA levels at 190 °C, 7.4 g/L, and 20.7% yield. Increasing the temperature to 210 °C accelerated the LA production while also achieving the lowest energy consumption, which was 0.47 kWh/g LA at the highest LA production point. However, longer treatments at this temperature caused LA degradation. AlCl₃ has been identified as an ideal catalyst for biomass conversion to LA, being inexpensive and low in toxicity. Full article

The study investigates the impact of water use in energy production in industrial plants, considering the interdependence between water and energy, or the water–energy nexus, to promote sustainable water and energy management. More specifically, it focuses on the industrial sector, particularly on electricity production in thermoelectric power plants, which require large amounts of water for cooling in its production cycle. The field of analysis is set in Italy, referring to the applications of the European Industrial Emissions Directive and Italian regulations that govern water and energy usage. The focus is on large combustion plants, which need to be monitored by national authorities. The Italian situation is outlined, exposing consumption data from major thermoelectric power plants in 2021 through 2023, highlighting the water usage trend and electricity production. In 2023, total water use for these installations was 9,892,719,965 m³—mainly from seawater—with an overall production of electric energy of 117,239,954 MWh, with a relevant fuel consumption from natural gas (18,544,742,774 Sm³). It also analyzed the application of best available techniques to reduce water consumption, recycle water flows, and minimize the environmental impact of power plants. Finally, the main fuels used in these plants, such as natural gas, coal, and biomass, are presented, along with the environmental performance of the power plants based on water use per unit of energy produced. Full article

Natural and liquefied petroleum gases are widely used in industrial heat treatment. However, the rising cost of gas, combined with increased demand, has significantly impacted production costs and the environment. The annealing process typically relies on natural or liquefied petroleum gases as the primary heat source. In this study, we aimed to investigate the use of biomass fuel as a replacement for fossil fuels and to evaluate the mechanical properties and microstructure of wire rod steel after annealing using indirect heat from a gasifier. We experimented to examine the effects of annealing temperatures of 650 °C, 700 °C (below the critical temperature Ac1), and 750 °C (above Ac1 but below the upper temperature Ac3). The batch furnace, made of stainless steel, was modified from a traditional wire annealing furnace that originally used CNG and LPG gas burners. It was adapted into a wire annealing furnace connected to a cross-draft gasifier. The furnace’s interior was designed with spiral cooling fins to minimize energy consumption and shorten annealing time. Additionally, it was modified to use biomass as a substitute fuel, reducing environmental pollution. The furnace was coated with thermal insulation, and the biomass gasifier stove was a cross-draft device with primary air feeding at 20 m³/h and secondary air supplied at a constant flow rate of 32 m³/h, 36 m³/h, or 40 m³/h. As a fuel source, we used eucalyptus. The mechanical properties of wire rod steel were measured in terms of tensile strength and torsion, following the TIS 138-2562 standard. This standard specifies that the tensile strength must be at least 260 MPa. Regarding torsion, the TIS 138-2562 requirements state that the wire must withstand at least 75 rounds of twisting without breaking. Our results showed that after annealing at 650 °C, 700 °C, or 750 °C, with a soaking time of 30 min and subsequent cooling in the furnace at natural temperature for 24 h, the tensile strength values were 494.82, 430.87, and 381.33 MPa, respectively. The torsion values were 126.92, 125.8, and 125.76 rounds, respectively. Additionally, ferrite grain size increased with annealing temperature, reaching a maximum of 750 °C. The total annealing duration for each batch was 2 h and 40 min at 650 °C, 2 h and 10 min at 700 °C, and 2 h at 750 °C. Full article

The iron and steel industry (ISI) plays a significant role in carbon emissions, contributing approximately 15% of the nation’s total emissions in China. Transitioning to low-carbon practices is crucial for achieving the country’s carbon neutrality goals. This paper reviews the current state of China’s ISI and assesses the feasibility of various decarbonization technologies, including hydrogen utilization, biomass substitution, zero-carbon electricity, Carbon Capture, Utilization, and Storage (CCUS), as well as their combinations. The blast furnace–basic oxygen furnace (BF-BOF) process currently dominates the industry with an overwhelming share of around 90%, presenting significant challenges for decarbonization. In contrast, the Direct Reduced Iron–Electric Arc Furnace (DRI-EAF) process is still at the demonstration project stage, but it is rapidly growing and shows great potential for achieving net-zero emissions. Electric arc furnaces (EAFs) that use scrap steel account for about 9% of production and have the lowest energy consumption. However, their production capacity is limited by the availability of scrap steel. Among numerous options, blue hydrogen, carbon-neutral biomass, and CCUS technologies have relatively low costs and high technological maturity. Nevertheless, no single technology can currently achieve deep decarbonization while significantly reducing costs. The nation needs to select the most suitable decarbonization strategies based on geographical location, infrastructure, and economic conditions. The government should enact corresponding policies, provide economic incentives, and ensure mitigation of the environmental and social impacts during the decarbonization transition. Full article

The urgent need for sustainable strategies to mitigate climate change has spurred the development of efficient carbon sequestration methods with minimal greenhouse gas emissions, presenting promising opportunities to produce biochar and, with this bioproduct, enhance crop productivity. Therefore, this research aimed to evaluate the carbon footprint produced by the low-temperature slow pyrolysis of biomass obtained from the pruning residues of four tree species present in parks and gardens of the southern Andean region of Ecuador. An electric reactor (ER), powered by 44 solar panels of 535 W each, was used to perform the pyrolysis process at 350 °C over four hours. For each species—Persea americana, Polylepis spp., Acacia spp., and Prunus salicifolia—three replicates of the process were conducted using 1.5 kg of biomass per trial. The results showed that Acacia spp. residues produced biochar with higher bulk density (0.303 g/cm³), organic matter (82.85%), total organic carbon (71.21%), oxygen (27.84%), C/N ratio (120.69), and potassium (459.12 ppm). The biochar produced from Prunus salicifolia exhibited the highest levels of pollutant gas emissions and carbon footprint (5.93 × 10⁻⁶ ton∙m⁻³ CO₂ eq and 0.001067 ton∙m⁻³ CO₂ eq, respectively). In contrast, the biochar produced from Polylepis spp. was the least polluting (0.001018 ton∙m⁻³ CO₂ eq), highlighting its potential as a source for biochar production from tree species found in the southern Andean region of Ecuador. Meanwhile, the pyrolysis of Persea americana (avocado) resulted in very low gas emissions, although it exhibited the second-highest carbon footprint due to the high energy consumption associated with the process. In conclusion, this study identified Persea americana and Polylepis spp. as the best options for biochar production through pyrolysis, positioning them as viable alternatives for developing sustainable strategies to mitigate climate change. Full article

The global rise in population and advancement in civilization have led to a substantial increase in energy demand, particularly in the industrial sector. This sector accounts for a considerable proportion of total energy consumption, with approximately three-quarters of its energy consumption being used for heat processes. To meet the Paris Agreement goals, countries are aligning policies with international agreements, and companies are setting net-zero targets. Upstream emissions of the Scope 3 category refer to activities in the company’s supply chain, being crucial for achieving its net-zero ambitions. This study analyzes heating solutions for the supply chain of certain globally operating companies, contributing to their 2030 carbon-neutral ambition. The objective is to identify current and emerging heating solutions from carbon dioxide equivalent (CO₂e) impact, economic, and technical perspectives, considering regional aspects. The methodology includes qualitative and quantitative surveys to identify heating solutions and gather regional CO₂e emission factors and energy prices. Calculations estimate the CO₂e emissions and energy costs for each technology or fuel, considering each solution’s efficiency. The study focuses on Europe, the United States, Brazil, China, and Saudi Arabia, regions or countries representative of companies’ global supply chain setups. Results indicate that heat pumps are the optimal solution for low temperatures, while biomass is the second most prevalent solution, except in Saudi Arabia where natural gas is more feasible. For medium and high temperatures, natural gas is viable in the short term for Saudi Arabia and China, while biomass and electrification are beneficial for other regions. The proportion of electricity in the energy mix is expected to increase, but achieving decarbonization targets requires cleaner energy mixes or competitive Power Purchase Agreement (PPA) projects. Brazil, with its high proportion of renewable energy sources, offers favorable conditions for using green electricity to reduce emissions. The utilization of biomethane is promising if costs and incentives align with those in the EU. Although not the objective of this study, a comprehensive analysis of CAPEX and lifecycle costs associated with equipment is necessary when migrating technologies. Policies and economic incentives can also make these solutions more or less favorable. Full article

This paper investigates the optimization of insulation thickness with respect to the integration of renewable energy systems in residential buildings in order to improve energy efficiency, maximize the contribution of renewables and reduce life cycle costs. Using the DesignBuilder and EnergyPlus software, this study models a representative two-story residential building located in Athens, Greece. The building envelope features extruded polystyrene thermal insulation and windows with unplasticized polyvinyl chloride frames and low-e glazing. Six scenarios with hybrid renewable energy systems are analyzed, including air- and ground-source heat pumps, solar thermal systems and a biomass fired boiler, so as to assess energy consumption, economic feasibility and internal air temperature conditions. A Pareto-fronts-based optimization algorithm is applied to determine the optimal combination of insulation thicknesses for the walls, the roof and the floor, focusing on minimizing the life cycle cost and maximizing the percentage of renewable energy utilized. The results demonstrate that scenarios involving biomass boilers and solar thermal systems, both for heating and cooling, when combined with reasonable thermal protection, can effectively meet the recent European Union’s directive’s goal, with renewable energy systems contributing more than 50% of the total energy requirements, whilst maintaining acceptable internal air temperature conditions and having a life cycle cost lower than contemporary conventional buildings. Full article

This research paper analyzes the use of plasma technology to process biomass in the form of dried, mixed animal manure (dung containing 30% moisture). The irrational use of manure as well as huge quantities of it can negatively impact the environment. In comparison to biomass fermentation, the plasma processing of manure can greatly enhance the production of fuel gas, primarily synthesis gas (CO + H₂). The organic part of dung, including the moisture, is represented by carbon, hydrogen, and oxygen with a total concentration of 95.21%, while the mineral part is only 4.79%. A numerical analysis of dung plasma gasification and pyrolysis was conducted using the thermodynamic code TERRA. For 300–3000 K and 0.1 MPa pressure, the dung gasification and pyrolysis were calculated with 100% dung + 25% air and 100% dung + 25% nitrogen, respectively. Calculations were performed to determine the specific energy consumption of the process, the composition of the products of gasification, and the extent of the carbon gasification. At 1500 K, the dung gasification and pyrolysis consumed 1.28 and 1.33 kWh/kg of specific energy, respectively. A direct-current plasma torch with a power rating of 70 kW and a plasma reactor with a dung processing capacity of 50 kg/h were used for the dung processing experiments. The plasma reactor consumed 1.5 and 1.4 kWh/kg when pyrolyzing and gasifying the dung. A maximum temperature of 1887 K was reached in the reactor. The plasma pyrolysis of dung and the plasma–air gasification of dung produced gases with specific heats of combustion of 10,500 and 10,340 kJ/kg, respectively. Calculations and experiments on dung plasma processing showed satisfactory agreement. In this research, exergy analysis was used to quantify the efficiency of the plasma gasification of biomass. One of the research tasks was to develop a methodology and establish standards for the further standardization of monitoring the toxic emissions of dioxins, furans, and Benzo[a]pyrene. Full article