Woody Biomass Utilization Research Articles

High yield production of fungal manganese peroxidases by E. coli through soluble expression, and examination of the activities

Oxidative enzymes of white-rot fungi play a key role in lignin biodegradation. Among those fungus, Ceriporiopsis subvermispora degrades lignin before cellulose in wood; C. subvermispora is the only fungus that secretes all known types of manganese peroxidases (CsMnPs). Utilization of lignin-degrading peroxidases has been limited so far due to the lack of efficient preparation methods and intensive characterization. In this study, we developed a highly efficient method to prepare active CsMnPs through soluble expression by E. coli, which had long been impossible. The genes of MnPs selected from each subfamily were codon-optimized and expressed under the control of a cold shock promoter. A proper level of heme incorporation was achieved by continuous addition of hemin during cultivation. As much as 3 mg of purified MnPs was obtained from 100 mL culture, which is an about 20-fold higher yield than that from inclusion bodies through refolding. Further improvement of the solubility on the expression was achieved by combinatorial coexpression of chaperones. All obtained MnPs had heme-to-protein ratios as high as those of native MnPs. They were all active below pH 5. Our method is applicable to other fungal-secreted enzymes should help the progress of their basic characterization and application for better utilization of woody biomass.

‘Woods-to-Wake’ Life Cycle Assessment of residual woody biomass based jet-fuel using mild bisulfite pretreatment

The residual woody biomass (a.k.a. harvest slash) produced during forest harvest operations in the Pacific Northwest is generally collected into piles and burned and/or left on the forest floor to decompose. Producing drop-in biofuels from this residual cellulosic feedstock can provide an alternative use for this unused resource while simultaneously displacing petroleum based fuels. Utilizing a ‘Woods-to-Wake’ (WoTW) Life Cycle Assessment (LCA) approach, which is comparable to a Well-to-Wake (WTW) LCA for petroleum based aviation fuel, this paper assesses the environmental implications of feedstock recovery, production, and utilization of residual woody biomass based biojet fuel. This paper also presents a comparative assessment of the environmental implications of substituting petroleum based jet fuel with that of residual woody biomass based biojet fuel.The bioconversion process presented in this paper uses a mild bisulfite pre-treatment of the feedstock to liberate the C5 and C6 sugars which then go through enzymatic hydrolysis and saccharification to produce fermentable sugars. The sugars are then converted to bio-jet fuel (iso-paraffinic kerosene, IPK) using a proprietary biocatalytic fermentation and oligomerization process. The WoTW environmental implications of producing woody biomass based jet-fuel are then compared to the WTW environmental impacts of producing petroleum based jet-fuel. The results reveal that the WoTW global warming impact of residual wood based bio-jet fuel represents a 78% improvement over the WTW global warming impact of petroleum-based jet fuel.

An Evaluation of Sustainable Woody Biomass Resource Utilization Policy in the West Tottori Region

From a viewpoint of local production of energy for local consumption, this study conducts regional economic analysis using an input-output table of a local area, and measures the socio-economic impacts of woody biomass utilization policies with a constraint of input resources amount for sustainable use. Two scenarios are analyzed. The one is “end material use policy of woody biomass”, which resulted in 1,234 (mil. yen/year) of total regional output increase, while the other is “small-scale electricity generation policy”, which resulted in 2,905 (mil. yen/year).

Balancing formal and informal success factors perceived by supply chain stakeholders: A study of woody biomass energy systems in Japan

Small-scale woody biomass energy systems have an inherent ability to aid in emissions reduction while stimulating local economies and, as collective energy systems, are strongly connected to supply chain design based on local conditions and stakeholder integration. Despite an abundance of forest area alongside the promotion of biomass in energy policies, however, woody biomass utilization still remains low in Japan. The woody biomass supply chain, considered as a socio-technical system, involves a complex, cross-sectoral stakeholder network in which inter-organizational dynamics necessitates well-organized management based on an understanding of formal factors such as technology, as well as informal factors such as social relations and culture. In this paper, success factor perceptions from across the woody biomass supply chain are investigated based on semi-structured interviews with four stakeholders in the Kyushu region of Japan. Identified success factors here are: 1) respect of values & traditions, 2) transportation infrastructure, 3) business model integration, 4) relationship & trust, 5) local vitalization and 6) biomass quality control. A convergence as well as divergence of perceptions are observed, involving both formal and informal dimensions. Aiming to balance perceptions and to enable long-term success of woody biomass in Japan, a series of policy implications are drawn, including cross-ministerial integration, knowledge building on wood logistics, forest certification, local coordinators, biomass quality control standards and a feed-in-tariff for heat. This paper suggests a new arena of policy-making based on the importance of considering both informal and formal dimensions in energy policy.

第1報告 木質バイオマス利用の視点・政策・課題(木質バイオマス利用の取り組みと課題 : 岩手県の事例を中心に,2003年度北日本林業経済研究会公開シンポジウム)

第1報告 木質バイオマス利用の視点・政策・課題(木質バイオマス利用の取り組みと課題 : 岩手県の事例を中心に,2003年度北日本林業経済研究会公開シンポジウム)

石炭・木質バイオマス混焼火力発電における木質バイオマス利用の実態－東北を事例に－

石炭・木質バイオマス混焼火力発電における木質バイオマス利用の実態－東北を事例に－

Designing the scale of a woody biomass CHP considering local forestry reformation: A case study of Tanegashima, Japan

Biomass has become a renewable resource for energy, but it needs continuous management to make it truly renewable. Planted forests in particular areas in the world are facing the challenges of reformation because of the severe maldistribution of forest age-classes caused by a stagnation in demand for wood or degradation by past deforestation. In these regions, the amount of wood processed and the overall biomass must be controlled by a schedule of forestry reformation. Particularly for energy plants, where a continuous and adequate supply of wood is required, the scale of the plants should be carefully designed to maintain a harmonized demand/supply balance in the region. In this study, we considered the scale design for a combined heating and power (CHP) system using woody biomass for district heating and cooling (DHC) in Tanegashima, a remote island in Japan, which requires immediate forestry reformation in addition to mitigating its fossil-fuel consumption. A process model representing material and energy flows associated with the life cycle of a biomass CHP system was developed, which considered the dependency of timber consumption on the scale of the CHP, together with other design parameters. The profile of the annual timber supply for the next 100years to achieve sustainable forestry planning was calculated, which became the constraint on the feasibility of resource procurement for CHP. The ratio between the maximum and minimum timber supply in the next 20years was determined to be about 1.8. Through simulation and life cycle assessment (LCA) using the developed model, CHP scales were specified to cover the overall heat and power demand of consumers for biomass-derived energy at 840kWe with 1470kWth. We found feasible and effective scale ranges for the various stages of forest-resource status by comparing LCA results, timber consumption, and profiles for timber supply. We have been able to demonstrate that woody biomass utilization in a specific area should address forestry reformation in a sustainable way.

O-201 木質バイオマスの多用途利用をめざしたハウス暖房装置の開発(セッション2:技術2,口頭発表)

O-201 木質バイオマスの多用途利用をめざしたハウス暖房装置の開発(セッション2:技術2,口頭発表)

O305 高圧水蒸気圧縮成形法を用いた木質バイオマスの総合利用(セッション3:技術～木質利用～,口頭発表)

O305 高圧水蒸気圧縮成形法を用いた木質バイオマスの総合利用(セッション3:技術～木質利用～,口頭発表)

O-201 木質系バイオマスの連続式コンバージミル粉砕と酵素糖化特性(セッション2:技術1:エタノール変換,研究発表,(口頭発表))

O-201 木質系バイオマスの連続式コンバージミル粉砕と酵素糖化特性(セッション2:技術1:エタノール変換,研究発表,(口頭発表))

3-58 木質バイオマスのCCSを考慮した大規模利用技術の検討((15)評価1,Session 3 バイオマス等,研究発表(口頭発表))

3-58 木質バイオマスのCCSを考慮した大規模利用技術の検討((15)評価1,Session 3 バイオマス等,研究発表(口頭発表))

Marker recycling via 5-fluoroorotic acid and 5-fluorocytosine counter-selection in the white-rot agaricomycete Pleurotus ostreatus

Of all of the natural polymers, lignin, an aromatic heteropolymer in plant secondary cell walls, is the most resistant to biological degradation. White-rot fungi are the only known organisms that can depolymerize or modify wood lignin. Investigating the mechanisms underlying lignin biodegradation by white-rot fungi would contribute to the ecofriendly utilization of woody biomass as renewable resources in the future. Efficient gene disruption, which is generally very challenging in the white-rot fungi, was established in Pleurotus ostreatus (the oyster mushroom). Some of the genes encoding manganese peroxidases, enzymes that are considered to be involved in lignin biodegradation, were disrupted separately, and the phenotype of each single-gene disruptant was analysed. However, it remains difficult to generate multi-gene disruptants in this fungus. Here we developed a new genetic transformation marker in P. ostreatus and demonstrated two marker recycling methods that use counter-selection to generate a multigene disruptant. This study will enable future genetic studies of white-rot fungi, and it will increase our understanding of the complicated mechanisms, which involve various enzymes, including lignin-degrading enzymes, underlying lignin biodegradation by these fungi.

Variation in the physical properties of wood pellets and emission of aldehyde/ketone under different storage conditions

Considering self-heating and hazardous gaseous emission, the safety of wood pellets storage has become one of the important aspects for woody biomass utilization. In this study, the emissions of aldehydes/ketones were analyzed by high performance liquid chromatogram (HPLC). The properties of pellets stored in semi-closed tanks with different temperatures and relative humidity (RH) were also investigated. The emissions of aldehydes and ketones from pellets were increased with raising temperature and RH during storage, while the pellets’ physical properties (dimension, density, Meyer hardness and moisture content) were reduced, except for 70% and 90% RH runs. The fatty acids compositions were extracted from both the surface and the inner part of pellets, which were analyzed by gas chromatography–mass spectrometry (GC–MS). The interaction between pellets’ physical properties variation and unsaturated fatty acid oxidation was revealed by the investigation of differences of extracted unsaturated fatty acids concentration between the surface and the inner part of pellets, which affected the aldehydes and ketones emissions.

Current Situation and Tasks of Woody Biomass Utilization in Hokkaido

Current Situation and Tasks of Woody Biomass Utilization in Hokkaido

Evaluation of predictive models for Douglas-fir bark thickness at breast height following 12 biomass harvest treatments

Foresters often require an estimation of bark thickness from a reference height (typically breast height) to accurately estimate the bark or wood volume of a tree. Various models for estimating the bark thickness of interior Douglas-fir (Pseudotsuga menziesii var. glauca) from measured dbh (diameter at breast height) were evaluated. Sample trees were from northern Rocky Mountain mixed conifer stands that had been subjected to four levels of experimental woody biomass harvesting. Among simple linear, nonlinear, and segmented linear mixed effects models, the segmented linear model performed best. A join point (where the linear equations are linked) for the segmentation was statistically detected at approximately 19.0 cm dbh. The join point seems to indicate the size at which juvenile Douglas-fir trees boost the production of bark tissue, perhaps as those trees express dominance over competing understory vegetation. Woody biomass utilization level had no impact on bark thickness, indicating that the bark:dbh relationship does not depend on biomass utilization intensity. The study results enable accurate bark thickness estimation for interior Douglas-fir in this region, and suggest several silvicultural applications for juvenile Douglas-fir stand management.

The wood in the forest: Why California needs to reexamine the role of biomass in climate policy

Outlook The wood in the forest: Why California needs to reexamine the role of biomass in climate policy Peter Tittmann, Academic Coordinator, Woody Biomass Utilization Group, Center for Forestry, UC Berkeley I n California, the forestry sector and biomass energy producers have the potential to work together to reduce the state’s net greenhouse gas emissions, reliably generate renewable electricity, provide low- carbon building materials, support healthy forests and improve air quality. But wood energy producers are in a precarious position. Without quick policy changes, much of the state’s remaining biomass power plant capacity will soon be shut down. Roughly half of the power plants in the state that run on woody biomass are operating under power supply contracts set to expire by the end of 2016. Under current policies, it is likely that utilities will not offer new contracts at rates sufficient to cover the costs of operating these biomass plants. The biomass energy sector’s predicament stems in part from an otherwise positive development — the rapid expansion of low-cost solar photovol- taic power in California (fig. 1). Under California’s Renewables Portfolio Standard (RPS), one-third of the electricity provided by the state’s utilities must come from renewable sources by 2020. To meet these goals, utilities must contract with renewable power producers such as solar power installations, wind farms or biomass power plants. The price of electricity is a major factor in utili- ties’ power procurement decisions. As the price of power from new solar installations has dropped — it’s now in the range of 3 to 5 cents per kilowatt- hour less than what biomass plants can offer — utilities have little incentive to renew contracts with existing biomass power plants on terms that will allow the plants to stay open. But this simple price comparison misses two im- portant factors. First, by incentivizing better forest management and improved forest health, biomass energy leverages considerable climate and other en- vironmental benefits beyond the direct reductions in carbon emissions from generating electricity from a renewable resource. Second, biomass power plants provide consistent “base load” power output. Solar, by contrast, delivers intermittent power that declines in the afternoon as the demand for power peaks, complicating the management of the grid and requiring the operation of natural gas-fired “peaker” plants. This intermittency adds significant costs to the operation of the state’s power system that are not reflected in solar power’s low market price, but are passed on to ratepayers. Forestry and climate change The role of forests in climate change mitigation might seem simple: as trees grow, they remove http://californiaagriculture.ucanr.edu • JULY–SEPTEMBER 2015 133 Will Suckow The Buena Vista Biomass Power facility near Ione (Amador County) generates up to 18 megawatts of electricity from a mix of forest slash, urban green waste and woody biomass generated by farms.

Integration of Shiitake cultivation and solid-state anaerobic digestion for utilization of woody biomass

Pretreatment technologies that can not only reduce the recalcitrance of woody biomass but also achieve a high benefit-cost ratio are desirable for bioenergy production from woody biomass. In this study, an integrated process was proposed and conducted by pretreating woodchips via Shiitake cultivation for improved methane yield during solid-state anaerobic digestion (SS-AD), and simultaneously producing mushrooms as a high-value co-product. Shiitake cultivation using woodchips as the main substrate ingredient obtained mushroom yields comparable to those using a commercial substrate. Enzymatic digestibility and cumulative methane yields (133–160Lkg−1VS during 62days of SS-AD) of pretreated substrates (spent mushroom substrate) were at least 1.5times as high as those of untreated woodchips. Compared to a sole SS-AD process, the integrated Shiitake cultivation/SS-AD process increased methane production and solid waste reduction per kilogram of woodchips by about 1.5 and 8times, respectively.

Carbon Dioxide Emissions and Energy Self-Sufficiency of Woody Biomass Utilization for Residential Heating: A Case Study of Nishiwaga, Japan

Renewable energy sources, including bioenergy, are presently attracting considerable attention as possible substitutes for fossil fuels. Among the various sources of bioenergy, biomass can arguably play a significant role in the reduction of greenhouse gases and the provision of a stable energy supply. However, the use of fossil fuels continues in the production of bioenergy. Consequently, the overall extent to which biomass utilization for energy can reduce carbon dioxide emissions as a substitute for fossil fuels and whether this can improve the energy self-sufficiency rate remains largely unknown. This study responds to these questions using a case of a Japanese rural community using firewood for residential heating. The results showed that woody biomass utilization for energy is able to both reduce the dependence on fossil fuels and mitigate climate change. These findings offer new insights into the development of sustainability in rural communities.

Process analysis of the waste bamboo by using polyethylene glycol solvent liquefaction

Solvent liquefaction process is one of the promising techniques for the effective utilization of waste woody biomass. In the liquefaction process, waste woody biomass such as waste bamboo could be converted to liquid reactive materials for developing biomass-based materials since waste bamboo has an advantage of providing the liquefi ed products with a small range of variances. The components of liquefi ed waste bamboo released during the liquefaction reaction with the polyethylene glycol 400 (PEG 400) solvent is highly acidic in the presence of mineral acid catalysts. Therefore, this study was carried out for analyzing the behavior of the liquefi ed residues (LRs) from waste bamboo during the solvent liquefaction process. The LRs produced during the liquefaction process were measured and related to different liquefi ed conditions. The change in the morphological surface of the liquefi ed waste bamboo samples was observed by a scanning electron microscope. The chemical changes in the functional groups were analyzed by a Fourier transform infrared spectrometer. The crystalline structure of liquefi ed waste bamboo samples was determined by X-ray diffraction. The chemical composition analysis and particle size distribution of liquefi ed waste bamboo samples were also carried out to confi rm the results. It was found that the effi ciency of liquefaction process can be improved by increasing the temperature and the amount of acid catalysts, although condensation reaction occurred under the liquefaction condition with high temperature. The liquefaction period of lignin was signifi cantly shorter than one of cellulose in the solvent liquefaction process with PEG 400. Moreover, it is indicated that the progress of liquefaction process may be

Modeling Population Dynamics and Woody Biomass in Alaska Coastal Forest

Alaska coastal forest, 6.2 million ha in size, has been managed in the past mainly through clearcutting. Declining harvest and dwindling commercial forest resources over the past 2 decades have led to increased interest in management of young-growth stands and utilization of woody biomass for bioenergy. However, existing models to support these new management systems are very limited in number and value. This study presents a density-dependent, size-specific, and species-specific matrix growth model for forest in coastal Alaska. This model enables short- and long-term predictions of stand basal area, volume, and biomass in a simple and accurate way and facilitates understanding of the ecological and economic effects of forest management alternatives. Components of forest growth were estimated from tree- and stand-level attributes from repeated measurements of 544 Forest Inventory and Analysis permanent sample plots located throughout coastal Alaska with a wide range of stand conditions. The model was tested on 293 postsample validation plots and found to have significantly higher accuracy than the Forest Vegetation Simulator, the only growth model available for the region. Analysis of residuals revealed no spatial autocorrelation, which indicates that this model is able to adequately account for the effects of physiographic factors and other differences between southeast and southcentral Alaska.