Utilization Of Forest Residues Research Articles

Forest residues contribute significantly to climate change in China

Under the energy shortage and emerging climate change caused by fossil energy, forest residues were encouraged to be used as an energy resource. However, it is a challenge to quantify the forest residue at the fine spatial scale due to the available data and suitable research methods. We aimed to quantify the available forest residues in China at the county scale and clarify their potential contribution to climate change (CCC). The availability of forest residues reached 152.13 million t in 2018 in China. The CCC accumulated by natural decomposition of forest residues over one-hundred-year had reached 49.27 million tCO2eq. The peak values of provincial annual CCC were reached in the first 3 years in the southern region. The top four counties of CCC were all from Yunnan Province. The energy utilization of forest residues is of great significance to the management of forest resources.

Multicriteria evaluation of biomass residues in Portugal to second generation bioethanol production

Abstract Paper aims This study evaluates agricultural and forest residues in Portugal to select the best candidates to use in second generation bioethanol (2G bioethanol) production. Originality The growth in the significance and level of decisions in biomass resources to 2G bioethanol and the involved complexity clearly encourage a research strategy to identify and select the wastes according to a multiplicity of criteria. Research method To address the key research objective this research used a multicriteria decision analysis method, MACBETH, to structuring the values of concern and identifying the key criteria, to evaluating the main agricultural and forest waste with respect to each criterion, to weighting the criteria and analyzing the biomass residues overall attractiveness and exploring the model´s results. Main findings As main findings of the study we found that Eucalyptus waste is the most promising forest residue to produce lignocellulosic bioethanol followed by Paulownia Tomentosa waste. The utilization of forest residues to the production of bioethanol in Portugal may represent in the future an important economic activity with huge environmental benefits. Implications for theory and practice The multicriteria approach addressed the research objectives and is simple to use with great potential for circular economy strategy issues. The step-by-step explanation of the model building makes the approach highly acceptable to other practitioners.

Determining the priorities in utilization of forest residues as biomass: an A'wot analysis

AbstractThe gap between global energy production and consumption is increasing at a fast pace along with population growth, industrialization, and technological developments, resulting in a rapid increase in the need for energy. This has led countries to use their own resources more effectively. Consequently, in addition to existing energy sources, alternative solutions are now being sought for this problem via renewable resources such as biomass energy production. As forest resources are abundantly available in Turkey, forest residues constitute a significant biomass potential. This study aimed to identify key strategic factors in the evaluation of forest residues as biomass using A'WOT analysis. Measurement of the factors in SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis, and their ranking, was enabled by quantification via A'WOT analysis, which is a combination of SWOT analysis and the analytic hierarchy process (AHP). A survey was conducted among relevant experts in Turkey to determine SWOT factors and AHP weights. As a result, eight sub‐factors for strengths and threats, seven sub‐factors for opportunities, and four sub‐factors for weaknesses were determined for analysis. Each SWOT parameter was then quantified by considering the viewpoints of the surveyed experts, and the resulting matrix was used to determine the vector weights and priorities of the groups and factors. The results indicated that if forest residues could be utilized as an alternative energy source, this would more than fill the gap between the production and consumption of energy in the country. In the evaluation of forest residues in Turkey, transportation costs emerged as the weakest factor, while the removal of natural sources of nutrition and fertilizer from the forest cover was seen as the greatest threat. The most important opportunity was perceived to be the improvement of forest management along with energy and climate‐change policies and activities. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.

Potential of Natural-Origin Loblolly Pine Tree Fractions as A Bioenergy Feedstock

Chemical characterization was performed on ten different samples of loblolly pine ( Pinus taeda L . ), representing various woody components of trees (bole, slab, tops and branches, and whole tree) harvested from two naturally regenerated forests in southern Arkansas (USA). Ultimate analysis, proximate analysis using thermogravimetry, and the energy content of the samples were determined to help evaluate their bioenergy utility. These whole tree samples may be an attractive prospect for bioenergy applications such as gasification, pelletization, and combustion, owing to favorable heating content values and relatively low ash content. Although a number of logistical challenges exist in their acquisition and processing, slabs, topwood, and branches offer opportunities for bioenergy applications that can increase the utilization of forest residues without threatening more traditional uses of wood in lumber, panels, and paper. Finally, we then briefly consider the silvicultural implications of these results for naturally regenerated southern pine-dominated forests.

Impacts of silvicultural prescriptions and implementation of best management practices on timber harvesting costs

ABSTRACTRising costs of forest operations and decreasing revenue generated from harvesting are becoming critical challenges in forest management throughout the Northeastern US. Along with this, the low markets for comminuted forest residues and stricter policies on environmental protection have prompted utilization of these materials as slash mats on skid trails for minimizing soil disturbances. The aim of this study was to evaluate the cost of different silvicultural treatments and utilization of forest residues generated from a mechanized timber harvesting operation for implementing Best Management Practices (BMPs). The field-based experiment was done in central Maine, where four forest stands were managed at varying intensities following silvicultural prescriptions common to the region (partial harvest (PH) and clear-cut (CC) treatments). Variables measured included delay-free cycle times of various timber harvesting machines, predictor variables, and stand features. The total cost of PH was higher than that of CC ($22.94 m−3 versus $14.88 m−3). Of the various operational phases, the costs associated with skidding was the highest and ranged from 52 to 70% of the total cost for PH and CC, respectively. The cost of BMP implementation was estimated to be between $10 and $52 PMH−1 or $1.0 and $3.7 m−3, and was influenced by several factors, including machine maneuverability and the extent of area which demanded BMP implementation. This information on the cost and productivity for timber harvesting operations, along with BMP implementation, will support the development of economic and environmentally sustainable harvesting strategies.

Evaluating the production cost and quality of feedstock produced by a sawdust machine

The utilization of forest residues as a woody biomass feedstock for the production of bioenergy and bioproducts requires processing (i.e., comminution) to meet feedstock specifications, such as moisture content and particle size. The objective of this study was to determine the effect of small diameter processed hardwood (SH) and small and large diameter processed softwood (SS and LS) stems had on the productivity and cost of a track mounted sawdust machine that produced sawdust. In addition, moisture content, particle size distribution, bulk density, and the effect of knife wear were evaluated. The sawdust machine's 298-kW engine was capable of comminuting all material types except the LH stems. The machine's productivity ranged between 18.3 and 26.7 bone-dry metric ton (BDmT)/productive machine hour (PMH) at a cost of US $5.3 and US $3.6/BDmT, respectively. The moisture content of material used in the study ranged between 26 and 36%. The geometric mean particle lengths for SH, SS, and LS were 4.7, 5.3, and 4.4 mm, respectively. The machine could not process LH materials due to limited power. The bulk density of feedstock produced ranged between 234 and 281 kg/m3. Analysis indicated that knife wear did not have a significant effect on comminution productivity and feedstock quality while comminuting 60 green metric tons (GmT) of forest residues. The results from this study suggest that this sawdust machine can be useful in producing feedstock for new biomass conversion technologies that require small, uniform particles.

Caracterização física de painéis aglomerados de Eucalyptus grandis com adição de resíduos industriais madeireiros

A madeira de florestas plantadas constitui a principal fonte de matéria-prima para produção de painéis aglomerados no Brasil. O aproveitamento dos resíduos florestais para produção desses painéis ainda não foi implementado em nível industrial. Este trabalho teve por objetivo avaliar as propriedades físicas dos painéis de madeira aglomerada (MDP - medium density particleboard) de três camadas, fabricados industrialmente na linha de produção da empresa Eucatex S.A. Indústria e Comércio, utilizando madeira de Eucalyptus grandis e resíduos industriais madeireiros (material reciclado de paletes e serragem), em diferentes proporções, variando de 10% a 35% em volume. O material foi disponibilizado pela empresa, na unidade industrial MDP localizada no município de Botucatu - SP, onde foram fabricados os painéis em escala industrial. Os ensaios físicos foram realizados no Laboratório de Processo da Eucatex e no Laboratório de Ensaios de Materiais do Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas - UNESP - Botucatu, SP. Os resultados obtidos revelaram que os painéis estudados tiveram bom desempenho físico, atendendo, no geral, as especificações técnicas estabelecidas pelas normas técnicas, mesmo nos tratamentos com as maiores proporções de adições. O teor de umidade final do painel teve efeito nas propriedades estudadas com tendência generalizada de redução nos valores de absorção de água e inchamento em espessura quando o teor de umidade final do painel aumentou de 9% para 12,5%.

Climate impact potential of utilizing forest residues for bioenergy in Norway

The utilization of forest residues for bioenergy in Norway is foreseen to increase due to the government call to double bioenergy output by 2020 to thirty Tera-Watt hours. This study focuses on the climate impacts of bioenergy utilization where four forest residue extraction scenarios at clear-cut are considered: i) 75 % above ground residues (branches, (25 %) foliage, tops); ii) 75 % above and below ground residues (branches, tops, (25 %) foliage, stumps, coarse and small roots); iii) extracting 100 % of all available forest residue; and iv) leaving all residues in the forest. The Yasso07 soil-carbon model was utilized to quantify the carbon flux to the atmosphere due to the forest residues that are left in the forest in each scenario. The climate impact potential for each scenario was then calculated for the carbon-flux neutral Norway Spruce (Picea abies) forest system in five regions of Norway. The biogenic carbon dioxide emissions associated to decomposition upon forest floor, procurement losses and bioenergy conversion are included in these calculations. Results suggest that if such bioenergy can directly replace a fossil source of energy, the utilization of this biomass was found to be climatically beneficial in most fossil energy replacement cases and time horizons when compared to leaving the residues in the forest. Integrated global temperature change displacement factors have been developed which have been used to estimate the magnitude of this climate change mitigation over a particular time horizon.

A Brief Global Perspective on Biomass for Bioenergy and Biofuels

Biomass has a large energy potential. A comparison between the available potential with the current use shows that, on a worldwide level, about two-fifths of the existing biomass energy potential is used. In most areas of the world the current biomass use is clearly below the available potential. Only for Asia does the current use exceed the available potential, i.e. non-sustainable biomass use. Therefore, increased biomass use, e.g. for upgrading is possible in most countries. A possible alternative is to cover the future demand for renewable energy, by increased utilization of forest residues and residues from the wood processing industry, e.g. for production of densified biofuels (Parrika, 2004).If carried out on a large scale, the increased use of agricultural resources for energy will have the effect of raising the prices of most commodity crops and reducing the need for subsidies – with particular benefit for producers of commodity crops in developing countries. An aggressive program of bioenergy development could lead to reductions in government support to farmers without any loss of income. The long-term success of bio-based facilities and markets is dependent in part on the level of commitment of feedstock from forest landowners and farmers. Forest, crop, and animal residues present considerable potential as a biomass feedstock. They are renewable, sustainable, locally available, and often considered carbon-neutral when compared to fossil fuels (Hoogwijk, 2004; Mathews, 2008).