基于市场分析的中国生物质成型燃料状况

研究了2010年中国生物质成型燃料,尤其是农林剩余物成型燃料的发展情况.首先讨论了生物质成型燃料技术及其分类,然后分析了农林剩余物资源状况和能源利用潜能,最后对中国各个地区的生物质成型燃料发展状况进行了市场分析和优势、劣势、机会、挑战分析.分析表明:主要的农业剩余物和大部分林业剩余物可作为生物质成型燃料的良好原料,具有很大的能源利用潜能;在华中、华东、华南、华北和东北等地区生物质成型燃料市场发展情况较好;发展和提高生物质成型燃料技术及成型燃料燃烧技术,为成型燃料提供更多的激励和支持政策,建立更多成型燃料示范基地,提高公众环保意识及限制煤的不合理利用等将有利于中国生物质成型燃料的发展.     

生物质棒状成型燃料的物理特性研究

利用木屑、竹屑及玉米秸秆等生物质原料,采用棒状成型机将原料压缩为棒状成型燃料。试验测定了成型燃料的松弛密度、抗跌碎性、抗渗水性和吸湿性等物理特性参数。结果表明:生物质原料纤维排列形态对成型燃料的密度有影响,原料纤维形态结构排列整齐与零散结构相比,成型后成型燃料的密实度更好。生物质原料固定碳含量影响成型后成型燃料的表面颜色,固定碳含量低的生物质原料,成型后成型燃料的表面颜色较深。试验结果也表明了原料纤维形态和原料特性对成型燃料的抗跌碎性、抗渗水性及吸湿性均有重要影响。     

我国生物质成型燃料的研究进展

洁净、可再生的生物质成型燃料能源的利用,可以有效地缓解我国能源紧张的压力。本文主要介绍了近年我国在生物质成型燃料成型工艺条件和燃烧性能,以及混合型生物质成型燃料方面的研究进展,并指出今后我国应对生物质成型燃料的压制机理、燃烧动力学等方面展开深入研究。     

带二次通风口的炉箅子设计

目前我国燃料市场生物质成型燃料的使用还处于起步阶段,燃烧生物质成型燃料的专用设备也非常少.本文介绍一种燃烧生物质成型燃料炉灶专用的新型炉箅子.     

生物质成型燃料加工装备发展现状及趋势

从世界化石能源面临枯竭的角度出发,介绍了中国生物质资源状况和国内外生物质成型燃料成型技术及成型设备的应用现状,并针对中国的国情,提出了发展生物质成型燃料的途径和方法,以便充分、有效地利用农林剩余物等生物质资源.     

基于学习曲线的生物质成型燃料补贴政策研究

通过对中国生物质成型燃料产业的调研与分析,结合该产业的发展轨迹和国家相关的规划目标,构造中国生物质成型燃料的学习曲线,利用该曲线来预测中国固体成型燃料成本的变化趋势。在此基础上,研究如果2020年我国生物质成型燃料利用量要达到5 000万吨的规模,应该如何量化并制定政府的补贴政策。结果表明,若要在2020年实现将生物质成型燃料的商业化并达到5 000万吨的利用量,生物质成型燃料的成本需降低至462元/吨,此时学习系数为0.509,学习率为70.2%。为促使生物质成型燃料的技术进步和产业化发展,需要在2020年以前对该产业进行财政补贴,最大补贴规模为2016年的6亿元,从2012年到2020年的累计补贴为41.24亿元。     

生物质固体成型燃料研究进展

农林废弃物的资源化利用对于低碳环保和我国的能源结构转型具有十分重要的意义,介绍了农林废弃物的燃料化利用途径,归纳总结了生物质固体成型燃料在成型工艺,以及成型质量影响因素和炭化成型所用粘结剂等领域的研究现状,展望了生物质固体成型燃料性能的发展趋势,并提出了目前生物质固体成型燃料存在的问题及改进建议。     

生物质固化成型技术研究进展

生物质固化成型技术是目前利用生物质能比较普遍且效果显著的技术之一。它是将生物质压制为便于运输和贮存的棒状或颗粒燃料, 可以提高燃烧效率。文中综述了国内外生物质固化成型技术的开发利用现状, 从成型工艺、成型设备、影响因素和燃料炉具4个方面进行了总结, 并针对我国生物质能源现状提出了合理、充分开发生物质固化成型技术的相关问题和建议。     

生物质成型燃料锅炉设计

介绍生物质成型燃料的燃烧特性,阐述了生物质成型燃料锅炉各部件设计及参数的确定。     

新型生物质块状燃料常温成型机的设计

<正>生物质成型燃料是生物质能利用的一种重要途径,为了推动生物质成型燃料的产业化,很多学者针对生物质燃料的成型机进行了研究,比较典型的成型机有:螺旋挤压式成型机、压辊式成型机、活塞冲压式成型机。     

Forest biomass and root–shoot allocation in northeast China

Temperate and boreal forests act as major sinks for atmospheric CO₂. To assess the magnitude and distribution of the sinks more precisely, an accurate estimation of forest biomass is required. However, the determinants of large-scale biomass pattern (especially root biomass) are still poorly understood for these forests in China. In this study, we used 515 field measurements of biomass across the northeast part of China, to examine factors affecting large-scale biomass pattern and root–shoot biomass allocation. Our results showed that, Picea & Abies forest and coniferous & broadleaf mixed forest had the highest mean biomass (178–202 Mg/ha), while Pinus sylvestris forest the lowest (78 Mg/ha). The root:shoot (R/S) biomass ratio ranged between 0.09 and 0.67 in northeast China, with an average of 0.27. Forest origin (primary/secondary/planted forest) explained 31–37% of variation in biomass (total, shoot and root), while climate explained only 8–15%, reflecting the strong effect of disturbance on forest biomass. Compared with shoot biomass, root biomass was less limited by precipitation as a result of biomass allocation change. R/S ratio was negatively related to water availability, shoot biomass, stand age, height and volume, suggesting significant effects of climate and ontogeny on biomass allocation. Root–shoot biomass relationships also differed significantly between natural and planted forests, and between broadleaf and coniferous forests. Shoot biomass, climate and forest origin were the most important predictors for root biomass, and together explained 83% of the variation. This model provided a better way for estimating root biomass than the R/S ratio method, which predicted root biomass with a R² of 0.71.     

Inventory-based estimates of forest biomass carbon stocks in China: A comparison of three methods

Several studies have reported different estimates for forest biomass carbon (C) stocks in China. The discrepancy among these estimates may be largely attributed to the methods used. In this study, we used three methods [mean biomass density method (MBM), mean ratio method (MRM), and continuous biomass expansion factor (BEF) method (abbreviated as CBM)] applied to forest inventory data to estimate China's forest biomass C stocks and their changes from 1984 to 2003. The three methods generated various estimates of the biomass C stocks: the lowest (4.0–5.9 Pg C) from CBM and the highest (5.7–7.7 Pg C) from MBM, with an intermediate estimate (4.2–6.2 Pg C) from MRM. Forest age class is a major factor responsible for these method-induced differences. MBM overestimates biomass for young-aged forests, but underestimates biomass for old-aged forests; while the reverse is true for MRM. Further, the three methods resulted in different estimates of biomass C stocks for different forest types. For temperate/subtropical mixed forests, MBM generated a 92% higher estimate than CBM and MRM generated a 14% lower than CBM. The degree of the overestimates is closely related with the proportion of young-aged forest within total area of each forest type.     

Estimation of biomass,net primary production and net ecosystem production of China's forests based on the 1999–2003 National Forest Inventory

Abstract

The National Forest Inventory (NFI) is an important resource for estimating the national carbon (C) balance. Based on the volume, biomass, annual biomass increment and litterfall of different forest types and the 6th NFI in China, the hyperbolic relationships between them were established and net primary production (NPP) and net ecosystem production (NEP) were estimated accordingly. The results showed that the total biomass, NPP and NEP of China's forests were 5.06 Pg C, 0.68 Pg C year^?1 and 0.21 Pg C year^?1, respectively. The area-weighted mean biomass, NPP and NEP were 35.43 Mg C ha^?1, 4.76 Mg C ha^?1 year^?1 and 1.47 Mg C ha^?1 year^?1 and varied from 13.36 to 79.89 Mg C ha^?1, from 2.13 to 9.15 Mg C ha^?1 year^?1 and from ?0.16 to 5.80 Mg C ha^?1 year^?1, respectively. The carbon sequestration was composed mainly of Betula and Populus forest, subtropical evergreen broadleaved forest and subtropical mixed evergreen–deciduous broadleaved forest, whereas Pinus massoniana forest and P. tabulaeformis forest were carbon sources. This study provides a method to calculate the biomass, NPP and NEP of forest ecosystems using the NFI, and may be useful for evaluating terrestrial carbon balance at regional and global levels.     

Analysis of spatio-temporal changes in forest biomass in China

Forests play a central role in the global carbon cycle.China's forests have a high carbon sequestration potential owing to their wide distribution,young age and relatively low carbon density.Forest biomass is an essential variable for assessing carbon sequestration capacity,thus determining the spatio-temporal changes of forest biomass is critical to the national carbon budget and to contribute to sustainable forest management.Based on Chinese for-est inventory data (1999-2013),this study explored spatial patterns of forest biomass at a grid resolution of 1 km by applying a downscaling method and further analyzed spatio-temporal changes of biomass at different spatial scales.The main findings are:(1) the regression relationship between forest biomass and the associated influencing factors at a provincial scale can be applied to estimate biomass at a pixel scale by employing a downscaling method;(2) for-est biomass had a distinct spatial pattern with the greatest biomass occurring in the major mountain ranges;(3) forest biomass changes had a notable spatial distribution pattern;increase (i.e.,carbon sinks) occurred in east and southeast China,decreases (i.e.,carbon sources) were observed in the northeast to southwest,with the largest biomass losses in the Hengduan Mountains,Southern Hainan and Northern Da Hinggan Mountains;and,(4) forest vegetation functioned as a carbon sink during 1999-2013 with a net increase in biomass of 3.71 Pg.     

徐州市森林生物量的估算

利用森林蓄积量推算森林生物量的方法,系统研究了徐州市森林植被的生物量.徐州市森林的总生物量是1 397.81万t,其中,杨树林1 209.07万t,侧柏林52.39万t,银杏林34.04万t,杂木林46.62万t,灌木经济林44.51万t,其他灌木林11.18万t.分析了其特点,为全面核算森林生态效益提供依据.     

安徽省宜秀区人工杨树林碳储量研究

森林碳汇是指森林利用光合作用吸收大气中的CO2并以生物量的形式贮存在植物体内和土壤中的能力。近年来,随着人口的增长和经济的发展,人类排放温室气体持续增加,导致地球气候不断变暖,而森林所固有的吸收和固定CO2的功能即森林碳汇功能,能够有效地减少大气中的CO2浓度,起到减缓气候变暖的作用。本研究以安徽省宜秀区人工杨树林为研究对象,设置面积为0.24 hm2的样地一块,采取相邻格子法将其区划为20 m×30 m的乔木样方4块。在样方内进行每木检尺,每块样地选取平均标准木一株,供乔木层生物量测定,林分乔木层总生物量按转换系数进行计算。结果表明：研究地林分径级分布集中在18 cm～28 cm之间,林龄为10 a;无论在单木还是林分中,干生物量都占绝对主体地位;研究地10 a生人工杨树林乔木层每公顷碳储量为196.0016 t。     

The realisable potential supply of woody biomass from forests in the European Union

Forests are important for providing wood for products and energy and the demand for wood is expected to increase. Our aim was to estimate the potential supply of woody biomass for all uses from the forests in the European Union (EU), while considering multiple environmental, technical and social constraints.The potential woody biomass supply was estimated for the period 2010-2030 for stemwood, residues (branches and harvest losses), stumps and other biomass (woody biomass from early thinnings in young forests). We estimated the theoretical biomass potential from recent, detailed forest inventory data using the EFISCEN model. Constraints reducing the availability of woody biomass were defined and quantified for three mobilisation scenarios (high, medium, low). Finally, the theoretical potentials from EFISCEN were combined with the constraints to assess the realisable potential from EU forests.The realisable potential from stemwood, residues, stumps and other biomass was estimated at 744 million m³ yr⁻¹ overbark in 2010 and could range from 623 to 895 million m³ yr⁻¹ overbark in 2030, depending on the mobilisation scenario. These potentials represented 50-71% of the theoretical potential. Constraints thus significantly reduced the biomass potentials that could be mobilised. Soil productivity appeared to be an important environmental factor when considering the increased use of biomass from forests. Also the attitude of private forest owners towards increased use of forest biomass can have an important effect, although quantifying this is still rather difficult.The analysis showed that it is possible to increase the availability of forest biomass significantly beyond the current level of resource utilisation. Implementing these ambitious scenarios would imply quite drastic changes in forest resource management across Europe.     

不同营林措施对黔中马尾松天然次生纯林生物量的影响

以黔中地区马尾松天然次生纯林为研究对象,实施幼龄林抚育、中龄林间伐及近熟林择伐措施林分与对照林分生物量的对比结果表明:抚育林分的平均木、目标树和林分总生物量分别达到对照林分的1.83、1.59和1.15倍;间伐与择伐林分目标树生物量的年增长量均显著高于对照林分,间伐林分乔木层生物量的增长量与增长率均高于对照林分,抚育增加了平均单株生物量和乔木层总生物量,间伐与择伐对林分目标树生物量和乔木层总生物量的增长均有促进作用,对林下植被生物量的促进作用不明显。     

基于遥感信息的森林生物量估算研究进展

遥感技术已被广泛应用于植被和生态系统的定量研究中,特别是利用遥感技术快速准确地估算森林生物量已取得了突破性的进展。综述了遥感技术在森林生物量估算中的现状,分析了各种遥感数据源在森林生物量估算中的优缺点,并简要总结了遥感技术在森林生物量估算应用方面的发展趋势。     

Estimating forest biomass increment based on permanent sample plots in relation to woodfuel consumption: a case study in Kampong Thom Province,Cambodia

To assess the sustainability of forest use for woodfuel, above ground biomass increment must be examined against woodfuel consumption. However, reliable data on the biomass increment of tropical forests are very limited. In this study, we estimated above ground forest biomass increment in Kampong Thom Province, Cambodia, using two consecutive measurements of 32 permanent sample plots in 1998 and 2000, and forest inventory data of 540 plots collected in 1997. The permanent sampling plot data were used to determine the relationship between initial biomass and subsequent biomass increment over a 2-year period. This relationship was applied to the inventory data to obtain a robust estimate of biomass increment across the major forest types for the entire province. The weighted average annual above ground biomass increment for the whole province was 4.77Mg/ha, or 2.3% of biomass. Woodfuel consumption was estimated to be about 2% of biomass increment for the province, suggesting that deficiency of woodfuel may not occur in this province. However, localized variation needs to be taken into account and there is a need to examine the effects of stand age and factors such as soil type, microtopography, and species composition on biomass increment and to consider woodfuel collection rate in specific forest areas with respect to accessibility for firewood collection.