Forest Biomass Utilization Research Articles

Optimization conversion of willow biomass derived from phytoremediation into value-added hydrochars: Effects of temperature and medium on Cd/Zn distribution and application potentials

Effective treatment of plant biomass with potentially toxic elements (PTEs) is crucial for phytoremediation. Hydrothermal carbonization (HTC) offers an economical and eco-friendly solution by converting biomass into high-value hydrochar. However, the effects of reaction temperature and medium on the characteristics and metals distribution in hydrochars from PTEs-containing biomass remain unclear. This study explores the effects of different hydrothermal temperature (180–240 °C) and reaction media (H2O, HCl, H2SO4, H3PO4) on the hydrothermal properties of willow biomass containing PTEs, and the distribution and transfer rules of PTEs (Cd and Zn) and the application potential of hydrochar. The results indicated that hydrothermal temperature and acid medium significantly influenced WB conversion, affecting hydrochar properties such as carbonization degree and surface functional groups. Higher hydrothermal temperatures enhanced Cd and Zn fixation in the solid phase, while acid facilitated their migration to the liquid phase. More than 91.08 % of Cd and 88.41 % of Zn in the acid-added system are migrated into the liquid phase at hydrothermal temperature of 180 °C Hydrochar prepared under 180 °C and H3PO4 exhibited excellent adsorption performance for Cd2+ and Cu2+ (2.17 mg/g and 34.38 mg/g, respectively) in aqueous solution. Additionally, hydrochars exhibit high calorific values (20.52–28.01 MJ/kg), suggesting their potential as biofuel. This study provides technical foundation to support the resource processing and safe utilization of forest biomass containing PTEs.

Forest Biomass in Bioenergy Production in the Changing Geopolitical Environment of the EU

The article examines the potential utilization of forest biomass in bioenergy production in Europe, taking into account limiting and developmental factors. The methodology includes a strategic analysis and the use of PEST analysis to evaluate the market for wood biomass. In the context of the current geopolitical situation and the decarbonization goals of the EU, the authors recommend accelerating energy transformation and highlighting forest biomass as an alternative within renewable energy sources. A literature review indicates the need to revise EU assumptions to enable the use of wood for bioenergy production, taking into account the needs of the wood industry. The analysis of economic factors shows competitiveness of forest biomass against coal, yet challenges arise regarding resource availability and competition with other energy sources. Emphasis is placed on the necessity of sustainable forest resource management and technological innovation. In the context of an energy crisis, the article underscores the role of innovation and recycling in alleviating shortages in energy markets. Conclusions highlight the imperative to develop a sustainable energy strategy for forest resource management and engage EU countries in the development of new biofuel and renewable energy sources for energy security and environmental protection.

Northeastern American Forests: Natural Disturbances, Climate Change Impact, and the Utilization of Increasingly Damaged Forest Trees for Biofuel Production

Forests and forestry-related industries and ecosystem services play a critical role in the daily life of all societies, including in cultural, ecological, social, economic, and environmental aspects. Globally, there are about 4.1 billion hectares of forestland. In the United States, there are about 304 million hectares of forestland, covering about 34% of the total land area, and the forest product industry produces over USD 200 billion worth of forestry products annually. Evidence suggests these precious resources may be negatively impacted by climate change via direct and indirect processes, including wildfires, insect/pest pressure, drought, extreme storm events, increased air temperature, solar radiation, vapor pressure deficit, and other factors and variables that can be detrimental. All these can not only cause significant changes in the health and productivity of the forests, but can also cause the extinction, migration, and/or re-distribution of different tree species. Thus, humankind has the paramount responsibility to take policy, technologic, economic, environmental, and management decisions and actions to protect this vital resource for current and future generations, plants, and animals. This paper provides an overview of some of the important characteristics of forest environmental services, climate–environment–forest interactions with respect to forest health and productivity, climate change’s impacts on forest species, and the utilization of forest biomass for high-value products.

Optimizing Forest-Biomass-Distribution Logistics from a Multi-Level Perspective—Review

Forest and wood biomass represent a sustainable reservoir of raw materials and energy, offering a viable alternative to fossil fuels. These resources find extensive use in producing bioproducts, including solid wood and wood materials. The judicious exploitation of forest and wood biomass can be pivotal in reducing carbon emissions and securing material and energy independence. The business viability of producing valuable goods from woody biomass hinges on ensuring its sustained availability. This necessitates access to high-quality biomass at a minimal cost, demanding the efficient design of wood-biomass-distribution logistics. Furthermore, it is imperative to give equal weight to social and ecological considerations in shaping the forest- and wood-biomass-distribution logistics, thereby ensuring the sustainable utilization of this renewable raw material source. This article presents research focused on the business optimization of distribution logistics for specific forms of forest biomass used in wood material production. While most studies have primarily concentrated on the business or ecological issues of biomass utilization, this article offers a comprehensive insight by addressing business, ecological, and social facets in assessing and optimizing wood-biomass-distribution logistics. Multi-stakeholder life-cycle-assessment optimization takes into account the reduction of greenhouse gases as an ecological metric, with production costs and capital expenditure forming the business metrics. At the same time, the generation of employment opportunities is commonly regarded as the pivotal social criterion. There remains a necessity for further exploration into the potential social impacts of forest biomass utilization. Additionally, developing enhanced methodologies and decision-support tools for scheduling wood-biomass-distribution logistics that holistically consider business, ecological, and social criteria is an essential ongoing task.

A concise review of technologies for converting forest biomass to bioenergy

The use of biomass is vital in reducing the negative effects of rising fossil fuel consumption. Given its quantity and diversity, forest biomass has garnered a lot of interest among the many kinds of biomass. This study evaluates the various strategies for transforming woody waste into usable biofuels. Carbon dioxide emissions from traditional energy generation systems could be mitigated through the direct utilization of forest biomass. Low energy conversion rates, as well as soot emissions and residues, are some of the problems that come up when directly using forest biomass. The sustainability of direct energy generation from forest biomass is also seriously threatened by the lack of constant access to biomass. Co-combustion with coal and pelletizing biomass is two solutions proposed for this issue. Co-combustion of forest biomass with coal has the potential to lower the process's emissions of carbon monoxide, nitrogen oxides, and sulfides. This article reviews and discusses the biochemical and thermochemical mechanisms that can transform forest biomass into a variety of liquid and gaseous biofuels. Future research using cutting-edge sustainability assessment tools like life cycle assessment, exergy, etc. should investigate the sustainability of forest biomass conversion processes to bioenergy further.

The Impact of Integrated Harvesting Systems on Productivity, Costs, and Amount of Logging Residue in the Clear-Cutting of a Larix kaempferi (Lamb.) Carr. Stand

Two integrated harvesting methods have been primarily applied to increase the opportunity for forest biomass utilization. In Korea, small shovels with a carrier for cut-to-length harvesting (CTL system) and tower yarders for whole-tree harvesting (WT system) are commonly used for the transportation of tree assortments (i.e., sawlogs and logging residue). No previous studies are available in South Korea that have compared and highlighted the operational performance and yield of logging residues between the CTL and WT harvesting systems. Thus, our study’s main objectives were to (1) evaluate the productivity and costs of the two harvesting systems through a standard time study method and (2) estimate the amount of harvesting logging residue at the landing. The productivities of the CTL and WT systems were 1.45 and 2.99 oven-dried tons (odt)/productive machine hour (PMH), at a cost of 86.81 and 45.41 USD/odt, respectively. In the WT system, the amount of logging residue (2.1 odt/ha) collected at the landing was approximately four-times larger than that of the CTL system (0.5 odt/ha). Our results suggested that the WT system is a less expensive and more suitable system when there are markets demanding logs and biomass, whereas the CTL system remains a less expensive option for stem-only harvesting. Furthermore, these results are important for estimating the economic and environmental amount of residue that could be potentially recovered and utilized from the forest types included in the study.

Anaerobic Digestion of Lignocellulosic Waste Materials

Nowadays, the climate mitigation policies of EU promote the energy production based on renewable resources. Anaerobic digestion (AD) constitutes a biochemical process that can convert lignocellulosic materials into biogas, used for chemical products isolation or energy production, in the form of electricity, heat or fuels. Such practices are accompanied by several economic, environmental and climatic benefits. The method of AD is an effective method of utilization of several different low-value and negative-cost highly available materials of residual character, such as the lignocellulosic wastes coming from forest, agricultural or marine biomass utilization processes, in order to convert them into directly usable energy. Lignin depolymerization remains a great challenge for the establishment of a full scale process for AD of lignin waste. This review analyzes the method of anaerobic digestion (biomethanation), summarizes the technology and standards involved, the progress achieved so far on the depolymerization/pre-treatment methods of lignocellulosic bio-wastes and the respective residual byproducts coming from industrial processes, aiming to their conversion into energy and the current attempts concerning the utilization of the produced biogas. Substrates’ mechanical, physical, thermal, chemical, and biological pretreatments or a combination of those before biogas production enhance the hydrolysis stage efficiency and, therefore, biogas generation. AD systems are immensely expanding globally, especially in Europe, meeting the high demands of humans for clean energy.

Balsam fir (Abies balsamea (L.) Mill.) – Red spruce (Picea rubens Sarg.) forest productivity 35 years after whole-tree and stem-only harvesting in north-central Maine, USA

Global trends in the demand for forest products, decreasing total area of actively managed forests, and pressures to increase profit margins suggest that forest management intensity will continue to increase in the future. These trends have typically led to shorter rotation lengths and increased utilization of forest biomass to supply the bio-economy with feedstocks for energy, novel bio-chemicals, traditional pulp and paper, panels and solid forest products. The combined influence of increased utilization and shortened rotation lengths have raised concerns regarding potential soil nutrient depletion and corresponding reductions in site productivity. In response to these concerns, the Weymouth Point Study Area (WPSA) in north-central Maine was established in a spruce-fir forest in 1979 to quantify the effects of whole-tree harvesting (WTH) and stem-only harvesting (SOH) on nutrient cycling and site productivity in adjacent, paired watersheds with large fixed-area plots. From 1979 to 2016, 49 permanent sample plots were established across three soil drainage classes to evaluate tree- and stand-level growth and nutrition response to harvest residue management and silviculture practices. Harvest treatments were implemented in 1981 with SOH simulated by returning delimbing residues after WTH, including chipped tops, branches and foliage (CHP), and lopped-and-scattered residues (LOP). The harvested watershed was aerially treated with triclopyr herbicide in the fourth growing season following WTH to release naturally regenerated conifers from herbaceous and woody weed competition. Response to silviculture practices were evaluated following pre-commercial thinning (PCT) and the addition of ammonium-nitrate fertilizer (FERT) treatments initiated 10 and 12 years following WTH, respectively. Thirty-five years post-harvest, tree growth and nutrient uptake have not been significantly affected by WTH at this location. Mean tree size was positively influenced by PCT; however, FERT did not significantly affect mean tree size. There were also no significant effects of treatments on aboveground biomass production and net nutrient uptake in trees. These results suggest that WTH at final felling for bio-economy feedstock production in spruce-fir forests similar to those at the WPSA (Chesuncook catena soils) is sustainable. However, this hypothesis is based on mid-rotation assessment of tree growth as an indicator of sustainable forest management. Further research is required to confirm the absence of negative impacts on tree- and stand-level growth and nutrition through the end of the current rotation.

Mitigation Impact of Different Harvest Scenarios of Finnish Forests That Account for Albedo, Aerosols, and Trade-Offs of Carbon Sequestration and Avoided Emissions

The pressure to increase forest and land carbon stocks simultaneously with increasing forest based biomass harvest for energy and materials emphasizes the need for dedicated analyses of impacts and possible trade-offs between these different mitigation options including also forest related biophysical factors, surface albedo and the formation of biogenic Secondary Organic Aerosols (SOA). We analyzed the change in global radiative forcing (RF) due to changes in these climatic agents as affected by the change in state of Finnish forests under increased or decreased harvest scenarios from a baseline. We also included avoided emissions due to wood material and energy substitution. Increasing harvests from baseline (65% of Current Annual Increment) decreased the total carbon sink (carbon in trees, soil and harvested wood products) at least for 50 years. When we coupled this change in carbon with other biosphere responses, surface albedo and aerosols, decreasing harvests from the baseline produced the largest cooling effect during 50 years. Accounting also for the avoided emissions due to increased wood use, the RF responses of the two lowest harvest scenarios were within uncertainty range. Our results show that the effects of forest management on SOA formation should be included in the analyses trying to deduce the net climate impact of forest use. The inclusion of the rarely considered SOA effects enforces the view that the lower the harvest, the more climatic cooling boreal forests provide. These results should act as a caution mark for policy makers who are emphasizing the increased utilization of forest biomass for short-living products and bioenergy as an efficient measure to mitigate climate change.

Global warming implications from increased forest biomass utilization for bioenergy in a supply-constrained context

This article analyzes different forest management strategies to meet the increasing demand of biomass for bioenergy and assesses the resulting global warming implications. Applied to maritime pine forest plantations in Portugal, the assessed strategies are: full harvest of residues (FULL); sustainable and proactive management (SMART); expansion of forest plantations on abandoned farmland (EXP); and biomass import (IMP). A dynamic CO2 inventory was obtained for each scenario using a parametric stand-level C-flux model adapted to Portuguese conditions, which was then extended to the landscape-level and coupled to a dynamic climate model. The time-adjusted absolute global warming potential (AGWP) was then calculated at both stand and landscape levels, considering the timing of all CO2 emissions and uptakes (both fossil and biogenic). To test the robustness of the findings, a sensitivity analysis was performed. Results show that, in a supply-constrained context like Portugal, SMART and EXP management strategies can provide important global warming mitigation benefits (GWPbio < 0), although their supply-response is slow (long-term strategies). On the other hand, FULL and IMP management strategies show moderate to null AGWP reduction potential (0 < GWPbio < 1), while involving other possible risks (e.g., exacerbated soil erosion, nutrient depletion or uncertain impacts abroad), but their supply-response is fast (short-term strategies). National forest regulations and energy policies should be revised to address the drawbacks related to all management strategies and to unleash the multiple environmental benefits they can provide in the short- and long-term.

Preface

The International Conference on Forest Products (ICFP) 2019 is held for broadening the forest product science and technology dissemination.The ICFP 2019 is the second international conference, held by the Forest Products Research and Development Center, the Ministry of Environment and Forestry of the Republic of Indonesia. Implementation of the ICFP 2019 is a strategy to expand the research results dissemination to an international level and is a medium for researchers, scientists and stakeholders to exchange information and develop research collaboration.The theme of the ICFP 2019 “Adopting the Renewable Bioenergy and Waste Utilization to Support Circular Economy & Sustainable Environment” is a strategic theme that supports actions for sustainable management of forest resources and the environment. This proceeding present 28 results of research on technology and bioenergy development, increasing the value added of industrial waste and forest harvesting, increasing the value added of NTFPs and biomedicine, processing waste to diversify timber products, processing waste to improve the quality of forest products and biomass utilization. I hope the scientific information presented in this proceeding can be useful for the parties as a basis for policy formulation and the development of science.Thank you.Dr. Wening Sri Wulandari Chairman of Organizing Committee

Factors Affecting the Chipping Operation Based on the Screen Size of the Drum Chipper

Forest biomass has recently been highlighted as a renewable energy source in South Korea. As the Renewable Energy Certificate weight has been revised to encourage the use of forest biomass for energy production, forest operations have focused on the development of new technologies and harvesting methods for the extraction and utilization of forest biomass. This study examined the application of a drum chipper to forest biomass and analyzed the effects of screen size (40, 50, 65, and 80 mm) on productivity, cost, and particle size distribution. When the screen size was 40 mm to 65 mm, the chipping productivity improved by up to 3.6 times, the fuel consumption decreased by up to 29.7%, and the chipping cost was reduced by up to 31.9%. The fines content tended to decrease with an increase in screen size. The size of woodchips was less than 100 mm in length and ranged from 10 to 63 mm. The 65 mm screen was the most effective (e.g., producing optimal wood chip size at an acceptable production rate) for the chipping operation. Harvesting methods and drying time are also important factors that determine the utilization efficiency of forest biomass. Therefore, further research should be focused on the effect of moisture content on chipping productivity, power required, and fine particle size in forest biomass productions.

Assessment Techniques in Forest Biomass along the Timber Supply Chain

As a part of the renewable energy cycle, forest biomass resources are considered to be important renewable materials and energy sources in many countries. It is evident from international and local research into forest biomass utilization that several challenges must be addressed to ensure logging waste can be transformed into material of commercial value. Several logistical and supply chain challenges have already been identified, including uncertainty about the nature, amount, and quality of forest residues. In this context, this paper presents a summary review of estimation methods and techniques for managing forest and woody residue along the timber supply chain. The review examines both the opportunities and the challenges evident in the international forest residue estimation methods within each supply chain for primary and secondary forest resources. The review also discusses techniques for supply chain and management planning and highlights the limitations of existing information and communication technology (ICT) implemented for forest biomass research.

Forest bioenergy network design under market uncertainty

The forest industry is transforming itself in order to foster new product development by utilizing forest biomass. However, market instability of all types of forestry products has significant impact on the transformation approach of the industry. In this regard, we propose a two-stage stochastic optimization model to evaluate the proficiency of adding new assortments including terminals and bioenergy to existing forest supply chain, taking into account uncertainty of demand and price of final products. The model assesses the optimal bioenergy or biofuel processes among the potentials. A multicut L-shaped decomposition method is implemented to provide a profitable network design for any future scenario. Finally, the proposed model and algorithm are demonstrated through a case study in Newfoundland, Canada. The result shows that the stochastic solution creates a higher value compared to deterministic one. Moreover, risk metrics including variability index and downside risk are quantified to provide a clear vision for risk-averse decision makers.

Utilization of waste forest biomass: pelletization studies of torrefied sawmill wood chips

The paper presents the effects pelletization process of torrefied waste forest biomass – sawmill wastes. The sawmill waste are generated in significant quantities and has significant energy potential. The use of torrefaction and pelletization process enables to produce mechanically durable fuel pellets. Aim of the studies was to evaluate the effect of different kind of additives (binders) to torrefied waste forest biomass on pelletization process characteristic (production capacity, energy consumption) and properties of produced pellets (i.e. density, mechanical durability). The most effective binder among the tested was modified wheat starch. Pellets made with this addition were characterized by the highest mechanical strength.

Comparison of small area estimation methods applied to biopower feedstock supply in the Northern U.S. region

Increasing interest in utilization of forest biomass for bioenergy has prompted extensive contemporary research regarding costs, supply and technology for efficiently producing electricity and other forms of renewable energy. One challenge facing both researchers and users is obtaining precise estimates of available forest biomass within plausible supply areas for individual power plants. Due to the wide distribution of power plants poised to co-fire with forest biomass, assessing its availability requires methods that can yield precise and low-bias estimates of aboveground forest biomass and other key attributes at varying spatial scales. Small area estimation (SAE) methods have high potential to accomplish this due to the availability of national forest inventory data, combined with satellite imagery and other forms of remotely-sensed auxiliary information. The study assessed several indirect, direct and composite estimators of four forest attributes: aboveground tree biomass, biomass of small-diameter trees, biomass of tops and limbs, and volume at the county-level and within the estimated supply areas around power plants across 20 states in the contiguous Northern U.S. Composite estimators using both k-nearest neighbors imputation and multiple linear regression provided superior estimates of indicators of forest biomass availability based on both precision and bias at the county-level at sampling intensities as low as 10–20%, compared to the other SAE methods examined. The composite estimator using k-nearest neighbors imputation was subsequently shown to produce precise estimates of forest biomass availability for selected power plant supply areas.

Spatial limitations in forest biomass harvesting using Geographic Information System and Remote Sensing for an ecological and sustainable bioenergy framework

ABSTRACTAs the sustainable forest biomass harvesting process is highly influenced by the terrain, the heterogeneity, and the protection status of the landscape, this study highlights the GIS and Remote Sensing as important scientific tools, assisting in the planning process and integrating the appropriate spatial limitations for an ecological forest biomass extraction in a rational bioenergy utilization framework. This study is focused on the northwest Greece and particularly in the regional unit of Grevena which is part of the Western Macedonia region, the region with the highest unemployment rates in Greece. As the forests in the regional unit of Grevena occupy a significant percentage over half of the regional unit area, the emphasis on the sustainable harvesting and utilization of forest biomass for energy purposes could tackle unemployment rates, enhance the energy autonomy of the remote mountain villages, and reduce the Mediterranean forest fire risk. The spatial data process and the implied spatial limitations unfold a methodology procedure, which is revealing specifically quantified and illustrated results as are emerging progressively the oak forests of the regional unit of Grevena with biomass harvesting capabilities, which do not belong to the Grevena’s protected areas, have accessible slopes and lower diversity index.

Utilization of Wet Forest Biomass as both the Feedstock and Electricity Source for an Integrated Biochar Production System

Abstract. A belt dryer and gasifier generator set were integrated into a biochar production plant to use process heat to dry biomass feedstock from forest residuals and to provide electric power to the plant using a side stream of dried biomass. Experiments were conducted to characterize the dryer throughput and drying capacity using process heat from a stack heat exchanger attached to the biochar machine flare. A matrix of tests was conducted at high and low flow rates for both the heat exchanger air flow rate (which varied the temperature and heat input to the dryer) and the residence time of feedstock in the belt dryer. Mean feedstock input moisture during dryer characterization was 45% and the mean moisture after exiting the dryer was 27%. The optimal test condition, providing the greatest water removal rate, was determined to have high air flow rate through the heat exchanger and short dryer residence time. This condition was used to demonstrate the integrated system for an 8-h production day. The integrated system dried incoming feedstock from 36% to 22% with a dryer throughput rate of 495 kg h-1 w.b. and an evaporation rate of 88.8 kg h-1, providing the necessary dry feedstock for the 20-kW gasifier generator set and the biochar machine, which produced 75 kg h-1 of biochar. This system required the operational effort of 0.92 labor hours per production hour. Results from this demonstration indicate that the integrated system provides key benefits in a biochar production operation including greater control of feedstock drying and the ability to operate without an external (non-biomass) source of fuel for electricity generation. Keywords: Biochar, Biomass, Biomass drying, Forest residuals, Gasification, Pyrolysis.

Climate Change Mitigation Potential in Boreal Forests: Impacts of Management, Harvest Intensity and Use of Forest Biomass to Substitute Fossil Resources

The impacts of alternative forest management scenarios and harvest intensities on climate change mitigation potential of forest biomass production, utilization and economic profitability of biomass production were studied in three boreal sub-regions in Finland over a 40-year period. Ecosystem modelling and life cycle assessment tools were used to calculate the mitigation potential in substituting fossil materials and energy, expressed as the net CO2 exchange. Currently recommended management targeting to timber production acted as a baseline management. Alternative management included maintaining 20% higher or lower stocking in forests and final felling made at lower breast height diameter than used in the baseline. In alternative management scenarios, logging residues and logging residues with coarse roots and stumps were harvested in final felling in addition to timber. The net CO2 exchange in the southern and eastern sub-regions was higher compared to the western one due to higher net ecosystem CO2 exchange (NEE) over the study period. Maintaining higher stocking with earlier final felling and intensified biomass harvest appeared to be the best option to increase both climate benefits and economic returns. Trade-offs between the highest net CO2 exchange and economic profitability of biomass production existed. The use of alternative displacement factors largely affected the mitigation potential of forest biomass.

Examining the Social Acceptability of Forest Biomass Harvesting and Utilization from Collaborative Forest Landscape Restoration: A Case Study from Western Colorado, USA

Examining the Social Acceptability of Forest Biomass Harvesting and Utilization from Collaborative Forest Landscape Restoration: A Case Study from Western Colorado, USA