Wood Biomass Research Articles

Grapevine wood biomass as a new bio-adsorbent for methylene blue: equilibrium, thermodynamic, kinetic, and isotherm analyses, both linear and non-linear

Grapevine wood biomass as a new bio-adsorbent for methylene blue: equilibrium, thermodynamic, kinetic, and isotherm analyses, both linear and non-linear

Small wood pellet boiler 3-D CFD study for improved flue gas emissions employing flue gas recirculation and air staging

Wood biomass fuels have become increasingly important in terms of achieving future sustainability targets regarding RES, especially to reduce GHG and the use of domestic energy sources, on other hand with these fuels the pulutant air emissions have to be addressed with great attention. Nowadays, air staging and flue gas recirculation are often used as a primary emission reduction measure in large scale biomass fuel fired boilers, but their combined application in small scale commercial wood pellet boilers is not so common. The implementation of this approach to the small scale burning devices can enable further development of small boilers, in order to achieve a more complete combustion and reduction of pollutant emissions, especially CO, NOx, and PM. In the presented work a comprehensive numerical and experimental study on the combustion parameters is performed, in order to determine the overall combustion properties. A commercial 32 kW small-scale hot water wood pellet boiler was modified numerically from the operating point of view. The findings of this study, like different combinations of recirculated flue gases and secondary air amount, can serve as useful guidelines for the new innovative design and optimisation of the air and recirculated flue gas injection process parameters. The scenarios of this study, where recirculated flue gas was added to the secondary air, were beneficial. Optimally, a CO reduction of 63% was achieved by adding 30% of recirculated flue gas to the secondary air stream, and a 22% reduction was achieved for the NO emissions.

Ultrasound-assisted low-temperature catalytic lignin-first depolymerization of pine wood biomass to selectively produce propyl guaiacol

Lignin-first depolymerization of biomass using reductive catalytic fractionation is a promising option for the biorefinery as it selectively converts lignin to value-added phenolic monomers while preserving the carbohydrate fraction.

Uticaj industrijskih nusproizvoda na svojstva geopolimernih kompozita na bazi elektrofilterskog pepela

Geopolymers are materials made of chain molecules incurred by polymerization of geopolymer binders. geopolymers are defined as a solid and stabile aluminosilicate materials, made of industrial byproducts and liquid solutions. The experimental part of the dissertation, contains the results of physical-mechanical, microscopic and durability properties of geopolymer mortars and concrete based on fly ash. For the purpose of determining the effect of different byproducts on characteristics of geopolymer mixtures, 24 batches of mortar and 8 batches of concrete were made and tested. (converter slag, wood biomass ash, red mud, and waste glass) in the amount of 5% - 100% with different steps of replacement in relation to to the binder mass. The samples of geopolymer mortar and concrete were cured at an ambient temperature According to the test results some recommendations for the possible application of fly ash and other industrial byproducts for making geopolymer mortars and concretes are made. Tested materials might be used as construction building materials and according to their physical-mechanical characteristics and durability properties, they can be alternative solution for the traditional mortar and concrete mixtures.

Uklanjanje boje bemacid red adsorpcijom na piljevini i karbonizovanoj piljevini

Today, huge amounts of coloured wastewater, released into ecosystems are a big problem, because they have harmful effects on humans, the environment, as well as the aquatic environment. One of the common treatments for removing dyes from wastewater is the adsorption process, with an emphasis on the use of cheap adsorbents. Therefore, the subject of this paper is the possibility of removing the anionic dye bemacid red (BR) on wood biomass sawdust and carbonized sawdust. The experiments examined the equilibrium contact time, the effect of initial pH, the effect of adsorbent dose, as well as the effect of the initial adsorbate concentration on the process of adsorption. By applying linear kinetic models, it was found that the adsorption process follows a pseudo-second-order kinetic model. It was found that pH does not have a significant effect on adsorption onto carbonized sawdust. By examining the effect of the initial adsorbent dose, it was found that optimal adsorption requires twice the mass of sawdust compared to carbonized sawdust. The use of linear adsorption isotherms shows better agreement with the Freundlich model for both adsorbents. The maximum adsorption capacity for sawdust is 30.18 mg/kg, while for carbonized sawdust it is 74.60 mg/kg. Use of sawdust and carbonized sawdust can be an effective adsorbent for removing the dye bemacid red from wastewater, which is confirmed by the experiment on a real sample of wastewater. The obtained efficiency of dye removal from real wastewater for sawdust is 42.9 %, and for carbonized sawdust 95.1 %.

Mogućnosti korišćenja biomase iz šumarstva u cilju uspostavljanja cirkularne bioekonomije u Srbiji

In the last ten years significance of biomass is growing, due to exhaustion of fossil fuel reserves and their negative impact on climate and environment. In the region of Southeastern Europe, biomass is the most significant renewable energy source, due to abundance of forests and agricultural areas. Serbia is one of the countries of Southeastern Europe with significant potentials for using biomass from forests and wood processing industry in the form of wood residues. Despite its potential, the use of wood biomass in Serbia is not efficient. Significant amounts of wood residue produced in the course of tree felling and timber assortment production are left unused in forests. It is necessary to improve the national legislative and regulatory frameworks and support mechanisms for the rational use of biomass, make a precise assessment of its potential and promote the importance of the circular bioeconomy in Serbia in the coming period. The paper presents the results of a complex analysis of the current state of the circular bioeconomy in Europe Union countries, comparing with state in Serbia, the goals and initial results of the CEE2ACT project, and highlights the importance of the formation and long-term functioning of the National Bioeconomy Hub.

Investigation of Wood Biomass Ash on the Thermal Behaviour of Compressed Earth Bricks

Investigation of Wood Biomass Ash on the Thermal Behaviour of Compressed Earth Bricks

Valuing Interventions to Reduce Indoor Air Pollution— Fuelwood, Deforestation, and Health in Rural Nepal

Household energy use, forest and poverty are entangled in developing countries with environmental and health problems. Dependence on wood for cooking fuel generally increases the dependency of poor people on forests. This fuelwood consumption is not only linked to the forest environment, but also to the health of the inhabitants due to indoor air pollution. As the women are exposed more to the smoke pollution than the men, and children are more sensitive to it than adults, the issue of fuel is also linked with the gender and child issues. Fuelwood is the main source of cooking energy in Nepal and will remain so for foreseeable future. About 66 percent of households use wood as the main fuel for cooking. Only about 13 and eight percent households, mostly in urban areas, use kerosene and LPG respectively. The households using biogas as the main fuel is less than two percent [CBS (2002)]. One study shows that over 89 percent of total energy use in Nepal comes from the traditional fuels [ADB (2003)]. Wood and other biomass fuels (crop residues as well as animal dung) can substitute for each other, though most consumers have a general preference for wood over other biomass [FAO (1997)]. With socio-economic development, the fuel used by a household changes to better ones in the fuel-ladder. Everybody likes to maximise their utility by choosing more convenient and prestigious fuel subject to the budget constraint. Climbing the fuel-ladder generally means stepping up from dung cakes or crop residues, fuelwood, kerosene, biogas, LPG and ultimately to the electricity. Moving to the higher steps in the ladder means better respiratory health of the family members due to lower emission.

Itaconic Anhydride as a Green Compatibilizer in Composites Prepared by the Reinforcement of a Tung Oil-Based Thermosetting Resin with Miscanthus, Pine Wood, or Algae Biomass

Unsaturated vegetable oils with conjugated carbon–carbon double bonds, such as tung oil, can undergo free-radical polymerization, originating alternatives to petroleum-based materials. The introduction of fillers to vegetable oil-based polymer matrices results in composites with improved mechanical properties. In this work, thermosets were synthesized by the free-radical polymerization of a mixture of tung oil, divinylbenzene, and n-butyl methacrylate, and reinforced with bio-based fillers, namely Miscanthus, Pinus taeda (also known as southern pine), and algae (Microspora and Oedogonium) biomass. The effect of filler particle size on the composites’ properties was evaluated. Additionally, to develop a better interaction between the hydrophobic resin and the hydrophilic reinforcements, and improve the mechanical properties of the composites prepared, itaconic anhydride, a bio-based molecule derived from itaconic acid, was added to the resin. Thermogravimetric analysis (TGA) showed that the presence of itaconic anhydride improved the overall thermal stability of the composites. The storage modulus of the composites at room temperature, assessed by dynamic mechanical analysis (DMA), was increased by approximately 32% and 68%, for Miscanthus and southern pine composites, respectively, when itaconic acid was added to the resin. It was also observed that the glass transition temperatures were not significantly affected by the presence of itaconic acid. Scanning electron microscope (SEM) images indicated better matrix-reinforcement adhesion in the presence of itaconic anhydride.

Growth and Mortality of Hybrid Poplar Short Rotation Culture (AF8 Clone) in Response to Clostera anastomosis L. (Lepidoptera: Notodontidae) Defoliation

The increasing worldwide interest in renewable energy and carbon storage has led to the development of relatively fast solutions to obtain wood biomass. The cultivation of fast-growing tree species in short-rotation crops, such as hybrid poplar clones, is one such solution, at least in temperate areas. Sometimes these monocultures are affected by disturbing factors, including severe insect defoliation, with strong destructive effects. The impact of defoliation on the growth and productivity of poplar crops is often estimated in the context of artificial defoliation. There have been few studies in which the effect of defoliation was calculated after natural defoliation. Among defoliating insect species, Clostera anastomosis L. is one of the most important defoliators of young poplars. This species developed severe defoliation in a 4-year-old poplar clone AF8 crop, from the northeastern part of Romania, in the spring and summer of 2017. The study aimed to assess the impact of defoliation both on the growth and mortality of defoliated trees and the productivity of the affected crop. To reach this goal, the height and radial growth of 150 trees with different defoliation rates (50 non-defoliated, 50 partially defoliated, and 50 completely defoliated) were measured and the defoliation symptoms and mortality were also evaluated for 4780 poplars (10% of the analyzed population). The defoliation caused a significant decrease in the annual height growth (28.6% of the partially defoliated trees and 38.5% of the completely defoliated trees) and a severe decrease in the radial growth, between 82.2% and 90.4%, respectively, depending on the defoliation rate. These strong decreases led to a significant decline in tree-level biomass accumulation, approximately 74.8% for partially defoliated trees and 83.1% for completely defoliated trees, for the year of defoliation. As a result, the loss in total biomass (for the four years of the rotation) was between 28.1% and 34.6%, respectively, depending on the defoliation rate. Therefore, the total biomass loss was 5 t·ha−1, representing approximately 70% of the forecasted production for 2017 only (approximately 7 t·ha−1).

The impact of climate policy and climate change on pm2.5 emission from residential wood combustion

Residential wood combustion is the dominant source of particulate matter PM2.5 in the Republic of Croatia. Although the wood biomass is considered a green, sustainable energy source, at the same time the inhalation of PM2.5 particles from residential wood combustion, is associated with harmful effects on human health. The paper analyzes the variability of PM2.5 emission regarding three factors, which are closely related to climate policy and climate change. The first factor is related to the introduction of new, more environmentally friendly wood biomass combustion technologies. The second factor relates to the consumption of wood biomass depending on climate variability. The third factor refers to the implementation of measures for energy renovation of family houses. The aim of this paper is to distinguish the contribution of individual factors, both on the historical PM2.5 emissions from residential wood combustion, and on the emission projections up to the year 2050.

Enhanced capacitance of phosphorus, nitrogen, and oxygen tri-doped balsa wood-based porous carbon for supercapacitors

Porous activated carbons derived from ultra-low density biomass of balsa wood are prepared by a one-step phosphoric acid activation method under different impregnation ratios without using dopants or post-treatments. These carbon materials are investigated and evaluated in terms of their morphology, texture structure, surface properties, chemical properties, and physical properties, as well as their electrochemical performance. The results indicate that the prepared phosphorus, nitrogen, and oxygen tri-doped balsa activated Carbons (PNOACs) exhibited hierarchical pore structures (micro-, meso-, and macropores). The surface area, pore size distribution, and also the heteroatoms (P/N/O) content of balsa wood active materials can be effectively controlled by the phosphoric acid activation process. Using PNOAC600-2, the active material electrode in the three-electrode system possesses a maximum specific capacitance of 263 F g−1 at 0.5 A g−1. The corresponding specific surface area and total pore volume are 1191.65 m2 g−1 and 1.19 cm3/g, respectively; while the heteroatom contents of nitrogen, phosphorus, and oxygen are 0.62, 3.43 %, and 15 %, respectively. Both the hierarchical pore structures and the heteroatoms have great influence and contribution to the specific capacitance performance. The assembled symmetric supercapacitor also exhibits a good capacitance retention rate (91.48 %), long-term charge/discharge cycling stability, and energy density (9.2 Wh kg−1). Using the one-step phosphoric acid activation method, a new method for developing and utilizing high-value balsa wood in the field of electrochemical energy storage is provided.

Long-Term Behavior of Concrete Containing Wood Biomass Fly Ash

Wood biomass is widely used in the European Union as a fuel for the production of heat and electrical energy, generating a considerable amount of ash. The disposal of ash, especially its finest fraction, requires proper engineering solutions, since these particles contain heavy metals and caneasily pollute soil, groundwater, or air. In this work, wood fly ash with a high amount of pozzolanic oxides and one with a high CaO content were used in concrete as a 15% and 30% cement replacement. Incorporation of wood ash in concrete reduced the 28-day compressive strength of concrete by up to 37%, which was attributed to the low stiffness of the wood ash particles, while the 2-year compressive strength indicated very low pozzolanic reactivity. The capillary absorption of concrete increased with the increase in the ash content, but almost no influence on the gas permeability was observed. Wood fly ash with high CaO content reduced the drying shrinkage of concrete by up to 65% after 1 year. In a mix with 30% of high CaO fly ash, swelling occurred in the first days of hydration, which was attributed to the volume expansion due to the formation of portlandite and brucite, but did not lead to cracking or a decrease in long-term compressive strength.

Mechanical, thermal and durability investigation of compressed earth bricks stabilized with wood biomass ash

There is a growing interest in raw earth as an eco-material of building for its local character and the low energy consumption that characterizes its overall life cycle. This work evaluates the effect of the recovery of two biomass ashes (WBAa, WBAb), resulting from domestic wood heating on the mechanical, thermal and durability properties of compressed earth bricks (BWBAa, BWBAb). These specimens were obtained in a partial substitution of a silty-clay soil by WBA, in various proportions (0, 5, 10, 15 and 20 wt%). The specimens manufactured were compacted with a compaction stress of 10 MPa, exposed to the open air and kept in the laboratory at a 20 ± 2 °C temperature, then allowed to harden for 7 and 28 days. The mechanical level strength increases with wood ash content and with curing time. BWBAb has the best flexural and compressive levels strength caused by formation of compounds with binding properties, but BWBAa shows good thermal insulation. Capillary water absorption test was performed to prevent the durability of the elaborated specimens under water action. These bricks showed different behaviors in contact with water based on the different microstructure present in the two ashes. The experimental study conducted highlighted the benefits of the high periclase (MgO) content on the mechanical properties and durability of compressed earthen bricks.

Microwave Pyrolysis of Biomass: The Influence of Surface Area and Structure of a Layer

The paper presents the results of experimental research into lab-scale microwave pyrolysis of wood biomass. The influence of the surface area and the structure of the biomass layer on the characteristics of pyrolysis during microwave heating are discussed. We have established that the biomass layer structure and surface area have a significant effect on the yield of pyrolysis gas. The approach of creating artificial deformation of the biomass layer was tested. The elements of artificial porosity made it possible to increase the CO yield by 18% and 32% compared to the pyrolysis of a biomass layer with artificial channels and a uniform layer, respectively. The concentration of H2 was 33% higher compared to the layer without artificial pores and 3% lower compared to artificial channels. The yield of CO2 increased by 25%, and the yield of CH4 doubled. The experiments showed that the distribution of biomass on a half of the bottom of the crucible and the additional porosity of the biomass layer surface effectively increase the yield of the pyrolysis gas components. Recommendations for increasing the efficiency of microwave pyrolysis of biomass were formulated.

Microwave‐Assisted Treatment of Waste Wood Biomass with Deep Eutectic Solvents

Microwave‐Assisted Treatment of Waste Wood Biomass with Deep Eutectic Solvents

Whole life embodied emissions and net-zero emissions potential for a mid-rise office building constructed with mass timber

Increasing global interest in sustainable buildings has generated significant investment in the mass timber industry in recent years. Timber products including Cross-Laminated Timber (CLT) and glue-laminated timber beams (glulam) are a structurally sound, aesthetically pleasing, and potentially carbon reducing alternative to traditional steel or concrete framing. This study uses Life Cycle Analysis methodology to determine the total embodied carbon emissions for a four-story (10033 m2) office building using two design scenarios: a traditional design using structural steel framing and a mass timber alternative utilizing CLT and glulam. The work is founded on detailed material lists for the two building designs that were generated by an architectural contractor with both designs subject to strict evaluation regarding building and construction codes. In addition to a comparative embodied carbon emissions analysis, this study utilized building energy consumption models and existing utility data to estimate operational emissions throughout the lifetime of the building. Energy production with rooftop solar arrays was estimated to evaluate grid emissions avoidance and determine the potential to offset whole life embodied carbon emissions when evaluated over a 30-year time horizon with temporal grid emissions accounting. Three end-of-life scenarios were evaluated for the mass timber products to determine the fate of biogenic carbon stored in the wood biomass. For the three scenarios, different mass fractions were sent to the landfill, directly re-used, or processed into particleboard. Results for the cradle-to-grave embodied carbon emissions analysis show the steel design embodies 3999 t CO2-eq. (398.5 kg CO2-eq m−2) whereas the mass timber design offers an 80–99% reduction in embodied carbon totaling 50–795 t CO2-eq. (5–79 kg CO2-eq m−2) dependent on the end-of-life treatment of mass timber products. Of all the evaluated cradle-to-grave scenarios, the smallest required solar array to fully offset embodied carbon emissions in 30 years was 665 kW with the mass timber building and the end-of-life scenario where 75% of CLT and 95% of glulam were directly re-used with the remaining fractions manufactured into particleboard. Discussion focuses on the challenges and uncertainty in using solar arrays to offset emissions from building construction, operation, and end-of-life treatment, requirements for achieving true net-zero carbon buildings, and methodological limitations.

The Biogas Potential of Oxytree Leaves

This article describes the characteristics of th Oxytree (Paulownia) plant, both in terms of its impact on GHG emissions and its potential use to produce biofuel, i.e., biogas. The described research involved the physico-chemical and elemental analysis of the Oxytree leaf composition and its biogas efficiency depending on the harvesting method. Three different scenarios were considered: the freshest possible leaves—processed immediately after stripping from the living tree; after the first day of collection from pruned or harvested wood; after the first week of collection from pruned or harvested wood. The best results were achieved for the harvest of the freshest leaves—on average 430 m3/Mg (biogas) and 223 m3/Mg (methane) per dry organic mass. The highest yield of biogas in terms of fresh mass (FM) was obtained for leaves fallen and collected after 1 day—123 m3/Mg FM, and 59 m3/Mg FM (methane). Processing Oxytree leaves through anaerobic digestion will contribute to reducing the carbon footprint of wood biomass production and is an additional source of renewable energy and fertilizer product.

Evaluation of the Physical, Mechanical, and Calorific Properties of Briquettes with or without a Hollow Made of Wheat (Triticum aestivum L.) Straw Waste

Large amounts lignocellulosic biomass in the form of straw is leftover after wheat harvesting that could be utilized for beneficial purposes. The latter has led to the emergence of new technologies to make use of this resource. One such technology currently in use turns wheat straw into briquettes. In the present study, we have prepared and evaluated the physical, mechanical and calorific properties of two types of briquettes made of wheat straw. The two types of briquettes prepared were (i) hollow briquettes and (ii) solid briquettes. The densities of these briquettes obtained on a mechanical device with a crank mechanism were 1.169 kg/m3, irrespective of whether the briquettes were hollow or solid. The briquette densities are consistent with European standards. The calorific value of wheat straw was 17.69 MJ/kg. Although the calorific value was somewhat lower than the beech wood briquettes (18.38 MJ/kg), it is adequate for their combustion in both stoves and thermal power plants. The ash content of wheat straw was 9.1% (~10-fold higher than that of beech wood). The briquettes showed a compressive mechanical strength of 1.15–2.17 N/mm2 and splitting mechanical strength of 0.17–0.39 N/mm2 suggesting that the straw briquettes were well compacted and can be stable during transport and/or other manipulations. In conclusion, wheat straw briquettes have similar physical, mechanical and calorific properties to those prepared from beech wood biomass and are a viable solution to replace beech wood briquettes with similar efficiency.

Biochar improves the performance of Avena sativa L. grown in gasoline-polluted soils

This study investigated the effect of soil contamination by different concentrations of gasoline on oat (Avena sativa L.) and tested the effect of biochar supply to the polluted soils on the performance of oat plants. Oat seeds were sowed in contaminated soils with different concentrations of gasoline: 0% (control), 1%, 2%, 6%, and 10% (v/w), and grown for 2 weeks. Germination, fresh weight, root and stem length, photosynthetic parameters (i.e., chlorophyll content, PIABS, FV/FM, and NDVI), and total antioxidant power were analyzed. The results showed a remarkable negative effect on almost all the investigated parameters starting from the gasoline concentration of 6%. Based on these results, a new experiment was run by adding 5% (w/w) biochar (a carbon-rich byproduct of wood biomass pyrolysis) to the 6% and 10% polluted soils to test whether adding biochar had a beneficial effect on oat performance. The results showed that biochar supply greatly reduced the negative effects caused by gasoline on all the investigated parameters.