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对不同林业剩余物的棒状燃料的成型技术进行研究,重点分析进料间隙和进料速度对不同材性、粒度的林业剩余物的成型效果.结果表明:1)所有的林业剩余物只要将其含水率控制在15%~25%之间,最大粒度的宽、厚规格不超30 mm,通过调整进料间隙和速度均可加工成棒状燃料.2)进料间隙与原料粒度呈负相关,进料速度又与进料间隙呈负相关.即木屑、竹屑等粒度小的物料进料间隙要大,可调至4~5 mm,进料速度应控制在中速或中速以下(电机频率为6Hz或6 Hz以下);而杂灌、油茶果壳等粒度较大的物料进料间隙要小,可调至1~3 mm,进料速度应控制在较高速或高速间(电杌频率为8~11 Hz).3)成型燃料的密度取决于成型时的压力.通过选用孔长径比大的环模或控制进料间隙和进料速度来调节成型时的压力,可使不同林业剩余物的棒状燃料密度达到1 g/cm3以上.4)原料的物质组成和性质是成型燃料热值的决定因素.锯末、竹屑的棒状燃料热值在4 000 kcal/kg左右,而杂灌和油茶果壳一般在4 000 kcal/kg以下. 相似文献
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颗粒成型燃料制造及其应用 总被引:7,自引:0,他引:7
对木屑等原料采用内压滚动式成型机和相应工艺条件能连续稳定制造符合质量标准的颗粒成型燃料,生产能力达到250kg/h。当颗粒成型燃料应用于家庭等取暖炉时,制造成型燃料具有较好的经济效益和社会效益。 相似文献
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采伐剩余物固化成型技术 总被引:3,自引:0,他引:3
当今,采伐剩余物最有效的利用方式就是将其固化成能源燃料,本文着重介绍了采伐剩余物固化成型技术开发利用研究的意义和国内外最先进的固化成型技术和工艺装备。 相似文献
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当前森林资源和林业可持续发展的重要性及目前的严峻状况要求将可持续发展的理念深入到林业建设的各个层面,生物质固体成型燃料技术是生物质能可持续开发利用的一项重要技术,具有广阔的发展前景。笔者通过分析林区采伐剩余物利用上存在的问题,及不同采伐类型和产品类型的出材量、采伐剩余物总量等,对重点林区采伐剩余物重量进行了估算分析,阐述了生物质固体成型燃料技术在我国推广应用的可行性。 相似文献
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小径材和采伐加工剩余物的利用途径及工艺吴萌(西北林学院)随着木材采伐工业的发展,成过熟林日益减少,小径材生产比例显著增加。人工林的大力发展和次生林的更新改造,也使小径材数量迅速增长。另外据统计,林区采伐剩余物约占采伐量的38%~40%,加工剩余物约占... 相似文献
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生物质成型燃料加工装备发展现状及趋势 总被引:8,自引:0,他引:8
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. 相似文献
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Takuyuki Yoshioka Masahiro Iwaoka Hideo Sakai Hiroshi Kobayashi 《Journal of Forest Research》2000,5(2):59-65
The concept of a “harvesting system for unutilized forest biomass by a processor and a forwarder” is examined for the purpose
of constructing a system to harvest logging residues (or slashes) as a new resource for energy. The rate of slash harvesting,
α, and the energy input rate of hauling slashes,p (%), are defined as indices of the possibility of harvesting slashes and the utilization of slashes for energy, respectively.
From an analysis of the field experiment, both the volume of logs hauled by the forwarder per day,E
F (m3/day), andp are expressed as functions of the hauling distance,L(m). The productivity of the processor,E
P (m3/day), andL were used to calculate α. Results showed that α was approximately 0.95 for the experiment site, indicating that almost all
the slashes could be hauled. It was recognized that the energy utilization of slashes was feasible for this site becausep was less than 1 %. The hauling cost per unit weight of slashes was calculated as 15.4 yen/kg on an oven-dry weight basis.
This high cost clarified that the cost must be reduced by taking measures such as enhancing the hauling efficiency of the
forwarder.
A part of this paper was orally presented at the 5th Annual Meeting of the Japan Forest Engineering Society (1998). 相似文献
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本文综述了国内外关于森林土壤碳动态过程对氮沉降响应机制的研究进展,概述了大气氮沉降对土壤碳释放及其影响因子的作用机制,从土壤生物学特性、凋落物动态、土壤碳释放等方面揭示大气氮沉降对土壤碳平衡过程影响机制和机理,探讨了森林土壤碳动态过程对氮沉降响应的不确定性因素,并指出未来该领域研究重点。 相似文献
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Transgenic trees as a new source for biofuel have brought a great interest in tree biotechnology. Genetically modifying forest trees for ethanol production have advantages in technical challenges, costs, environmental concerns, and financial problems over some of crops. Genetic engineering of forest trees can be used to reduce the level of lignin, to produce the fast-growing trees, to develop trees with higher cellulose, and to allow the trees to be grown more widely. Trees can establish themselves in the field with less care of farmers, compared to most of crops. Transgenic crops as a new source for biofuel have been recently reviewed in several reviews. Here, we overview transgenic woody plants as a new source for biofuel including genetically modified woody plants and environment; main focus of woody plants genetic modifications; solar to chemical energy transfer; cellulose biosynthesis; lignin biosynthesis; and cellulosic ethanol as biofuel. 相似文献
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为了掌握市场上林源中药饮片中二氧化硫的残留情况,从而为林业资源的利用、林药资源加工技术规范的制定与执行以及林产品的安全监测提供参考依据,采用在国家标准的基础上自行改进的检测方法,对从市场上收集到的31种林源中药饮片中二氧化硫的残留量进行了检测。结果表明:未检出二氧化硫的有3种;二氧化硫含量30 mg/kg的有20种;其含量为30~150 mg/kg的有3种;其含量为151~400 mg/kg的有3种;其含量400 mg/kg的有2种。根据《中华人民共和国药典》中对中药饮片残留量的限制规定和文中的检测结果,黄柏、牡丹皮、合欢皮、陈皮、八角茴香等中药饮片的二氧化硫残留量超标,建议在林产品利用和监管时要特别加以注意。 相似文献
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本文在简述过程控制基本知识和过程控制的特点的基础上,讨论了过程控制在森林生态、林业生命科学、林业产业、林产品加工等林业现代化建设方面推广应用的现实意义,并提出了加快其推广应用进程的意见和在农林院校林业专业开设林业自动化课程的建议。 相似文献
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The recovery process of fallow stands in the mountainous region of Northwestern Vietnam was studied, based on a chronosequence of 1–26-year-old secondary forests after intensive shifting cultivation. The number of species present in a 26-year-old secondary forest attained 49% of the 72 species present in an old-growth forest. Total stem density decreased gradually from 172,500 ha−1 in a 3-year-old forest to 24,600 ha−1 in the 26-year-old stand, but stem density of larger trees (diameter at breast height (D) ≥ 5 cm) increased from 60 ha−1 in a 7-year-old to 960 ha−1 in the 26-year-old forests, which was similar to that of an old-growth forest. Annual biomass increment of the 26-year-old stand was 4.2 Mg ha−1 year−1. A saturation curve was fitted to biomass accumulation in secondary forests. After an estimated time of 60 years, a secondary forest can achieve 80% of the biomass of old-growth forests (240 Mg ha−1). Species diversity expressed by Shannon Index shows that it takes 60 years for a secondary forest in fallow to achieve a plant species diversity similar to that of old-growth forests. 相似文献