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在木质纤维素的生物降解和转化过程中,木质纤维素的复杂结构和木质素组分限制了碳水化合物的高效酶水解。过氧化氢预处理可以通过破坏木质纤维素的物理化学结构并氧化降解部分木质素,从而改善原料的酶水解效率。过氧化氢预处理主要有过氧化氢-酸、过氧化氢-碱、活化过氧化氢这3类预处理方法。笔者主要归纳了不同预处理过程中的木质素降解机理,总结了过氧化氢预处理强化木质纤维原料酶水解的效果,探讨了预处理对木质纤维原料降解产物的影响,评价了各类过氧化氢预处理的可行性和优缺点。最后,根据过氧化氢预处理的特点分析了过氧化氢预处理的研究策略,展望了过氧化氢预处理的发展趋势。从安全性和经济可行性的角度来看,低试剂用量、低温和低压的预处理条件是未来过氧化氢预处理的主要研究方向。 相似文献
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《内蒙古林业调查设计》1996,(3)
木质塑料木质塑料是一种新型的复合材料，其主要原料是由废旧塑料及木屑、木粉。国外称之为“合成木料”。木质塑料具有良好的物理力学性能，其热仰缩性和吸水性均比木材小，稳定性好，具有耐磨、不蛀、不易燃和可弯曲等特点，即可压成型，又可锯、刨、钉、漆。原料丰富，... 相似文献
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本文讨论了木质纤维自身胶合的问题，湿法纤维板是实现自身胶粘的典型例子，提出利用木质纤维原料生成实现自身胶合，以及木质纤维原料表面活化是实现良好先决条件，对木质纤维原料自身胶粘的研究寄予厚望。 相似文献
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以红柳为材料研究蒸汽爆破预处理强度系数lgR对木质组分和纤维素酶水解性能的影响。结果表明:蒸汽爆破处理对红柳中纤维素和木质素含量的影响并不显著,但是它可以有效破坏红柳的天然物理结构,并且导致大部分半纤维素(木聚糖)产生自水解反应生成单糖和低聚糖溶出,同时产生乙酸、甲酸和糠醛等小分子降解产物。基于纤维素回收率和纤维素酶水解得率分析,在蒸汽爆破强度系数达到4.239时(爆破温度210℃和保温时间10min)对红柳的预处理效果最佳,汽爆物料中纤维素的含量可达到52.4%,残余木聚糖含量仅为2.01%,并生成0.76%甲酸和3.17%乙酸。采用每克纤维素20.0FPIU的纤维素酶用量水解5%(w/w)该汽爆红柳物料48h,纤维素酶水解得率可达到86.6%(未处理的原料仅为15.5%)。这表明无化学品添加的蒸汽爆破是适于红柳糖化及生物炼制的一种有效的预处理方法。 相似文献
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木质生物的种类可分为两大类，一类是锯材厂等的废材、建筑废材、道路工程障碍木、堤堰漂流木、公园和行道树的修剪枝以及废弃货架等废弃的生物质；另一类是末利用的问伐材、枝条、伐根等林地废材。据估算，总体上这些未利用废材的约一半可以作为能源以及其他产品的原料使用。 相似文献
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<正> 1984年,我们在筹建纤维板厂时,从上海购进了一台 QMbC 型热磨机,该机仅适用于甘蔗渣、棉杆、芒杆、芦苇等非木质原料的制浆,而不适用于木质原料制浆。但因棉秆资源有限,必须改为木质原料,若重新购置制浆设备,又需投资10余万元。为节省开支,我们对QMbC 型热磨机的进料系统着手进行改进,使之既可用于非木质原料的制浆,又适用于木质原料的制浆,做到一机多用。经过努力,改进工作达到预期的目的。 相似文献
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白腐菌在木质纤维素降解中的应用进展 总被引：5，自引：0，他引：5
木质素由于具有各种生物学稳定的复杂键型而不易被微生物降解,进而阻碍了纤维素的降解利用,而纤维素是重要的能源性物质,同时又是纸浆的主要成分,因此有效利用木质纤维素的关键是木质素的去除。本文总结白腐菌在生物制浆、乙醇制备的预处理、堆肥和饲料的制备方面的应用,概括提高白腐菌利用效率的方法,并对使用白腐菌处理木质纤维素材料进行展望。 相似文献
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芬兰的林木生物质能源概况 总被引：1，自引：0，他引：1
文中简要介绍了芬兰林木生物质能源的基本情况、相关目标及面临的主要问题, 着重阐述了芬兰林木生物质能源的政策与措施, 提出了借鉴芬兰经验, 加快我国林木生物质能源发展的政策建议。 相似文献
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Renewable energy sources have received significant attention in European countries as a result of increasing dependence on energy imports and concerns over high prices of fuels and climate change. Although private forests in Croatia account for less than one quarter of all forests, they may play an important role in woody biomass energy production, due to their underutilized exploitation. The objective of this paper is to identify the willingness of private forest owners to supply woody biomass and to understand how this willingness is affected by certain owner, management and forest property characteristics. A survey conducted in Croatia in 2012 of a random sample of 350 private forest owners shows that almost half of them were willing to supply woody biomass. A random utility model was used to determine the factors influencing private forest owners’ willingness to supply woody biomass. The results showed that willingness to supply woody biomass was influenced by property size, management objectives (production of fuel wood for personal needs and using the forest for outdoor recreation), cooperation with other forest owners and owner age. In order to enhance woody biomass mobilization from private forests it is important to identify the owners who are willing to supply it and to provide them with financial and administrative support using a mix of developed forest policy instruments. 相似文献
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In Montana, USA, there are substantial opportunities for mechanized thinning treatments on public forests to reduce the likelihood of severe and damaging wildfires and improve forest health. These treatments produce residues that can be used to generate renewable energy and displace fossil fuels. The choice modeling method is employed to examine the marginal willingness of Montanans' to pay (MWTP) for woody biomass energy produced from treatments in their public forests. The survey instrument elicited social preferences for important co-benefits and costs of woody biomass energy generation in Montana, namely the extent of healthy forests, the number of large wildfires, and local air quality. Positive and statistically significant MWTP is found for woody biomass energy generation, forest health and air quality. MWTP to avoid large wildfires is statistically insignificant. However, MWTP for woody biomass energy diminishes quickly, revealing that Montanans do not support public forestland management that produces more than double the current level of woody biomass harvested for energy generation. These findings can be used by policy makers and public land managers to estimate the social benefits of utilizing residues from public forest restoration or fuel treatment programs to generate energy. 相似文献
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中国林木生物质能源潜力测算及变化趋势 总被引：1，自引：1，他引：0
基于各省份林业统计数据,文中利用自下而上分析方法测算了中国林木生物质能源的资源潜力,并对变化趋势进行分析。结果表明:1993—2013年中国林木生物质能源资源潜力由0.78亿t标准煤增长到1.05亿t标准煤,20年间增长了34.62%;从资源构成来看,灌木平茬剩余物和采伐剩余物是林木生物质能源的主要供给来源;从区域变化来看,不同省份资源潜力呈现明显差异,但全国平均水平的逐步提高并非个别省份资源潜力大幅度提高使然,而是绝大部分省份资源潜力的共同增长促成了平均水平的连年提高。 相似文献
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木质生物质快速热解生物油产率影响因素分析 总被引：14，自引：1，他引：14
木质生物质能是可再生能源的重要组成部分,快速热解技术是国内外木质生物质能源化的热点研究课题.本文在简要总结木质生物质快速热解技术的基础上,着重对快速热解过程中热解温度、升温速率、压力、气相滞留时间、木质生物质物料特性、催化剂、热解反应器等因素对生物油产率的影响进行了论述,阐明了提高生物油产率的快速热解工艺条件. 相似文献
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Elias Olofsson 《Scandinavian Journal of Forest Research》2019,34(1):39-52
Forestry and forest industry sectors have vital roles for many regional economies. Consequently, it is important to understand how the introduction of the iron and steel industry (ISI) as a new large consumer of woody materials may affect existing feedstock markets. The use of metallurgical coal can partially or fully be substituted by refined biomass. To analyze the potential consequences of a new woody consumer on regional markets, three regions in northern Sweden and Finland are used as a case. A regional partial equilibrium model is developed, the Norrbotten County Forest Sector Model (NCFSM), and applied on three different scenarios. The purpose of the study is to analyze the intra- and inter-regional effects increased competition for woody materials may have on regional markets and on the economic well-being of the regions. The result suggest that the total welfare effect is relatively small, however, some regional welfare distributional effects are observed. Additionally, the price of roundwood will only be moderately affected if the ISI sector switch from fossil fuels to refined woody biomass. However, secondary woody materials, i.e. by-products and harvesting residues, will experience larger price shifts. 相似文献
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In this study we investigate the implications of reaching the 2 °C climate target for global woody biomass use by applying the Global Biosphere Management Model (GLOBIOM) and the recently published SSP-RCP scenario calculations. We show that the higher biomass demand for energy needed to reach the 2 °C target can be achieved without significant distortions to woody biomass material use and that it can even benefit certain forest industries and regions. This is because the higher woody biomass use for energy increases the demand for forest industry by-products, which makes forest industry final products production more profitable and compensates for the cost effect of increased competition over raw materials. The higher woody biomass use for energy is found to benefit sawnwood, plywood and chemical pulp production, which provide large amounts of by-products, and to inhibit fiberboard and mechanical pulp production, which provide small amounts of by-products. At the regional level, the higher woody biomass use for energy is found to benefit material production in regions, which use little roundwood for energy (Russia, North-America and EU28), and to inhibit material production in regions, which use large amounts of roundwood for energy (Asia, Africa and South-America). Even if the 2 °C target increases harvest volumes in the tropical regions significantly compared to the non-mitigation scenario, harvest volumes remain in these regions at a relatively low level compared to the harvest potential. 相似文献
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Sam Riffell Jake VerschuylDarren Miller T. Bently Wigley 《Forest Ecology and Management》2011,261(4):878-887
Forest harvest operations often produce large amounts of harvest residue which typically becomes fine (foliage, small limbs and trees) and coarse woody debris (snags and downed logs). If removed at harvest, residual biomass has potential to be a local energy source and to produce marketable biofuel feedstock. But, CWD in particular serves critical life-history functions (e.g., breeding, foraging, basking) for a variety of organisms. Unfortunately, little is known about how forest biodiversity would respond to large scale removal of harvest residues. We calculated 745 biodiversity effect sizes from 26 studies involving manipulations of CWD (i.e., removed or added downed woody debris and/or snags). Diversity and abundance of both cavity- and open-nesting birds were substantially and consistently lower in treatments with lower amounts of downed CWD and/or standing snags, as was biomass of invertebrates. However, cumulative effect sizes for other taxa were not as large, were based on fewer studies, and varied among manipulation types. Little is currently known about biodiversity response to harvest of fine woody debris. Predicting the effects of biomass harvests on forest biodiversity is uncertain at best until more is known about how operational harvests actually change fine and coarse woody debris levels over long time periods. Pilot biomass harvests report post-harvest changes in CWD levels much smaller than the experimental changes involved in the studies we analyzed. Thus, operational biomass harvests may not change CWD levels enough to appreciably influence forest biodiversity, especially when following biomass harvest guidelines that require leaving a portion of harvest residues. Multi-scale studies can help reduce this uncertainty by investigating how biodiversity responses scale from the small scale of manipulative experiments (i.e., 10-ha plots) to operational forest management and how biodiversity response to CWD levels might vary at different spatial and temporal scales and in different landscape contexts. 相似文献