焦油对生物质气化再燃还原NO的影响

采用配制含焦油模型化合物的生物质气的方法,实验研究了焦油的加入对生物质气化再燃还原NO的影响.模拟的生物质气化气由H2、CH4、CO、CO2、N2构成,并选择了苯、甲苯、苯酚和苯乙烯作为焦油模型化合物.实验在电加热的刚玉管流反应器中进行,实验温度在900～1,400,℃之间.研究了反应器入口焦油含量、氧气浓度、NO初始浓度、反应停留时间及反应温度等因素对还原NO的影响,分析了含焦油的生物质气化再燃特性.证实了焦油有助于提高生物质气化气还原NO的效率;含焦油的生物质气化再燃的最佳当量比在1.20～1.65之间,并且随着NO初始浓度的增加及停留时间的延长,NO还原效率逐渐增加;高温下,焦油含量较高时,有炭黑生成.     

介绍四种生物质气化的滤清系统

介绍四种生物质气化的滤清系统泰国Ｔｈａｍｍａｓａｔ大学Ｎ．Ｃｏｏｖａｔｔａｎａｃｈａｉ辽宁省能源研究所何元斌译［译者按］生物质气化所产生的煤气，含有一定量的焦油和灰尘，必须给予过滤清除，尤其用于气化发电时，就更为必要。泰国Ｔｈａｍｍａｓａｔ大学在进行...     

生物质气化气中焦油非催化裂解实验研究

生物质气化是一种环境友好的新能源利用技术,焦油作为生物质气化的副产物,是限制气化技术发展的主要因素.试验针对生物质气化产出气中焦油在700～1 000℃裂解温度区间的裂解特性进行了分析,并提出了焦油裂解产气率的概念.试验表明,焦油裂解气可以成为生物质气化气的有效的能量补充,而且随着裂解温度的升高,焦油裂解产气率增加,焦...     

降解生物质气化焦油废水菌种的分离筛选

选育高效降解生物质气化焦油废水的微生物一直是生物法处理焦油废水的难点和关键问题。通过选择性培养基的分离、解脂酶活性的测定及对不同浓度焦油废水的降解试验，从沈阳郊区秸秆气化站的生物质气化焦油废水中筛选出了4株降解能力较高的菌株。在焦油废水含量为100ml／l时，4株菌株的COD去除率均大于50％，最高可达80.14％。     

户用型生物质气化炉主要技术性能的试验研究

在实验台上针对改进型户用生物质气化炉进行了主要技术性能的试验研究,其中包括生物质原料、鼓风量、气化强度等参数对气化性能的影响,净化装置的脱除效果研究以及焦油回流装置对气化指标的影响等。实验表明,生物质原料的有关参数对气化性能有明显影响;鼓风量是气化炉生产负荷最简单迅速的调节手段之一,鼓风量存在一个最佳运行的鼓风量范围;户用型气化炉设计的净化装置脱除效果显著;焦油回流装置设计合理,提高了燃气品质和气化效果。     

生物质焦油裂解的技术关键

生物质焦油是生物质气化过程中有害的副产物，它会降低气化效率，影响设备运行，所以必须加以有效利用和处理。本文介绍了国内外焦油催化裂解的研究现状，详细地分析了讨论了催化裂解的关键过程和工艺件，总结出了焦油催化裂解的最佳条件和比较有前景的工艺路线。     

生物质气化发电燃气焦油脱除方法的探讨

生物质气化发电技术的最大难点之一就是如何除去燃气中含有的焦油等污染物,这些成分会对燃气轮机或内燃机等设备造成一定的影响.因此生物质气化发电过程中燃气焦油的脱除是目前国内外重点研究和解决的课题之一.文章在研究国内外大量有关文献资料的基础上,深入阐述了气化过程中焦油产生的机理、影响焦油生成的因素以及焦油的脱除方法,重点探讨了目前较为有效的焦油热化学脱除方法,即焦油的热裂解和催化裂解方法,以期为生物质气化发电燃气焦油的脱除提供一些思路和参考.     

生物质CO2/空气混合气氛下气化焦油析出特性研究

以松木木屑和水稻秸秆作为生物质原料,在自制小型气流床气化炉上开展CO_2/空气混合气化焦油析出特性实验研究,考察CO_2/C比、温度和生物质种类对焦油产率、组分和露点温度的影响。结果表明,相比于纯空气气化,CO_2/空气混合气化能降低焦油产率,促使焦油组分发生改变,特别是杂环化合物和重多环芳烃组分。随着CO_2/C比升高,松木和秸秆的焦油露点温度总体先升高后下降。不同种类的生物质添加相应量的CO_2能有效控制焦油析出,改善产气品质。     

生物质气化副产有机污染物脱除及防控技术现状

有机污染物作为生物质热化学转化过程中的主要副产物，严重影响了该技术的应用前景；其中，有机污染物主要包括焦油、硫化物、氮化物等。焦油常温下粘结附于设备和管壁，造成设备堵塞；硫化物、氮化物等气化副产有机污染物对人体健康和生态环境产生严重危害。因此，该文从生物质气化技术入手，结合国内外有机污染物脱除及防控技术，对生物质气化过程中产生的焦油、硫化物、氮化物的来源、危害及处理方法进行了详细分析，展望了有机污染物防控技术的发展方向，以期为生物质气化过程中有机污染物脱除及防控提供可借鉴的经验，进一步促进生物质资源的高值化利用。     

一种融入GRA的生物质气化焦油脱除LSSVM建模方法

提出一种融入灰色关联度分析(GRA)的生物质气化焦油脱除最小二乘支持向量机(LSSVM)建模方法。该模型考虑生物质气化焦油脱除过程影响因素的多样性和不确定性,通过试验数据的GRA分析,提取气化焦油脱除过程的强相关因素作为模型训练样本,建立生物质气化焦油脱除过程GRA-LSSVM模型,可有效克服传统建模方法对所有数据样本等同处理而造成的模型精度不高的不足。对松木屑气化焦油脱除过程建模分析,验证模型的有效性和准确性。     

生物质气化焦油生成碳黑的实验研究

生物质气化焦油有还原NO的作用。在小型管流反应器上进行的生物质气化气焦油还原NO的过程中有碳黑产生,对试验产生影响。碳黑对人体健康也极具危害。虽有研究表明碳黑有还原NO的作用,但其效果不如焦油裂解之后的小分子永久气体还原NO的效果好,因此再燃过程中有必要对碳黑生成进行控制。对几种典型的生物质焦油模型化合物（苯、甲苯、苯乙烯）燃烧生成碳黑的重要起始参数进行实验测定,得到不同再燃温度条件下（900～1400℃）,苯、甲苯和苯乙烯燃烧生成碳黑的起始碳氧比。本试验结果将对含焦油的生物质气化气再燃试验起到指导作用。     

Catalytic steam reforming of tar for enhancing hydrogen production from biomass gasification: a review

Presently, the global search for alternative renewable energy sources is rising due to the depletion of fossil fuel and rising greenhouse gas (GHG) emissions. Among alternatives, hydrogen (H₂) produced from biomass gasification is considered a green energy sector, due to its environmentally friendly, sustainable, and renewable characteristics. However, tar formation along with syngas is a severe impediment to biomass conversion efficiency, which results in process-related problems. Typically, tar consists of various hydrocarbons (HCs), which are also sources for syngas. Hence, catalytic steam reforming is an effective technique to address tar formation and improve H₂ production from biomass gasification. Of the various classes in existence, supported metal catalysts are considered the most promising. This paper focuses on the current researching status, prospects, and challenges of steam reforming of gasified biomass tar. Besides, it includes recent developments in tar compositional analysis, supported metal catalysts, along with the reactions and process conditions for catalytic steam reforming. Moreover, it discusses alternatives such as dry and autothermal reforming of tar.     

流光电晕放电净化粗燃气焦油及粉尘研究进展

研究焦油及粉尘的高效净化方法对推动生物质气化技术的发展具有重要意义。流光电晕放电过程产生的O、H、OH等活性自由基可有效裂解燃气中的焦油类有机物分子,在直流基压上叠加窄脉冲电压则可实现粉尘的荷电及高效气-固分离,是一种较有应用前景的粗燃气净化方法。笔者对流光电晕放电净化粗燃气焦油及粉尘的技术进展进行了综述,分析了该过程的裂解焦油/除尘机理、研究现状及关键科学问题,并提出了一种基于电旋风等离子体反应器的焦油及粉尘同时净化方法。最后针对生物质气化粗燃气净化过程中的瓶颈问题,简要归纳了其研究重点。     

增压锅炉烟气净化器试验与仿真对比分析

保证锅炉涡轮增压机组燃气轮机可靠工作的重要部件是烟气净化器。根据净化器的实际工作环境和特点,通过建立试验模型,使用树脂小球、聚苯乙烯小球和小米三种试验颗粒模拟烟气颗粒进行试验,应用试验和仿真两种手段对烟气净化器的分离效率和影响因素进行了分析。通过综合归纳和整理,得出了模拟试验与仿真相吻合的分离效率和影响因素。     

Catalytic decomposition of biomass tars: use of dolomite and untreated olivine

Although biomass is getting increased attention as a renewable energy source, one of the remaining problems still to be solved is the reduction of the high level of tar present in the product gas from gasification of biomass. The purpose of the present work is to study the activity of olivine and dolomite for tar destruction. Some researchers investigated olivine as bed material for biomass gasification. But it is not yet known how tars behave in the presence of olivine and whether olivine has some activity towards tar destruction. A slipstream from a lab-scale atmospheric bubbling-fluidised-bed gasifier (located at ECN) is passed through a secondary fixed-bed reactor where the additives are placed. For easy understanding, the results are represented in terms of the following tar classes; GC-undetectable tars (class 1), heterocyclic compounds (class 2), aromatic compounds (class 3), light polyaromatic compounds (class 4), heavy polyaromatic compounds (class 5). The general observation is that the conversion of all tar classes increases as the temperature was raised from 800 to 900 °C for both additives. The water-soluble heterocyclic compounds can be easily converted by thermal treatment. At the temperature of 900 °C, the water-soluble heterocyclic compounds are completely converted. A 48% decrease in heavy PAHs is observed with pure sand. Addition of 17 wt% olivine to the sand leads to a 71% decrease of PAHs at 900 °C, whereas addition of 17 wt% (pre-calcined) dolomite converted 90%. Also improvement in conversion of other tar classes is observed when olivine and dolomite are added during hot gas cleaning. A total tar amount of 4.0 g m₀⁻³ could be reduced to 1.5 and 2.2 g m₀⁻³ using dolomite and olivine, respectively, at a temperature of 900 °C. Inspite of this reduction in total tar concentration, a limited impact on the tar dewpoint is observed.     

柴油机废气净化系统的研究

研制了一种柴油机排出废气净化系统，主要包括捕集器、燃烧净化器和控制装置。该系统以液化石油气为能源，具有自动再生、净化效果良好的功能。在X195柴油机上的试验研究表明，该系统能够在柴油机较宽转速和负荷范围内有效净化柴油机排出废气，微粒净化效率达80％左右，HC／CO的净化效率达50％左右。     

煤气化过程中焦油裂解的试验研究

煤在热解和气化过程中产生的焦油，影响系统的正常运行。焦油脱除方法可分为气化炉内(初次脱除)和气化炉外(二次脱除)两类。尽管二次脱除法非常有效，但由于气化炉内初次脱除可以大大减少出口煤气中焦油含量，减轻甚至消除后期处理焦油的压力，故气化炉内脱除法得到重视。采用石灰石为催化剂，在1MW热态试验台上进行了试验，研究焦油和煤气成分在空气气化时添加不同石灰石含量工况下的变化情况，结果表明，石灰石的加入降低了焦油产率，提高了煤气产率，改善了煤气质量。     

发展户用生物质气化炉

讨论了户用生物质气化炉的炉体、炉膛、气体回流装置及净化器的结构设计和技术特点,分析了推广使用存在的问题,并提出了户用生物质气化炉的产业化发展思路。     

Life cycle assessment of olive pomace gasification for an up-draft fixed bed gasifier system

Biomass gasification has been considered as an important renewable energy alternative to deal with the environmental problems originating from fossil fuels and climate change effects. Olive pomace as a by-product of the olive oil production process is a significant biomass source. Although gasification technology is accepted as an environmentally friendly power system, the studies to determine its environmental impact via Life Cycle Assessment (LCA) are very limited. LCA is a key tool to evaluate all environmental impacts from the beginning to the end of the process. The aim of this study is to assess the overall environmental impacts of the olive pomace gasification for electricity generation and evaluation of its solid by-products namely biochar and tar. Four scenarios were compared to estimate the environmental impacts of gasification by-products with a LCA approach, following to the cradle-to-grave approach. The production of olive, olive pomace generation during its processing for olive oil production, gasification of olive pomace, construction of the gasifier, gas cleaning system and syngas composition have been included in the evaluations. It is clear from the analysis results that the scenarios have very low impact values in the case of beneficial usage of biochar in different industries. In terms of ozone layer depletion potential (2.74 × 10 ⁻⁶ kg CFC11 eq) and global warming potential (36.99 GWP100a), the paramount scenario from an environmental viewpoint is the scenario having the biochar and tar usage as a resource in another industry.     

Experimental analysis of air-steam gasification of biomass with coal-bottom ash

Biomass gasification is an attractive option for producing high-quality syngas (H₂+CO) due to its environmental advantages and economic benefits. However, due to some technical problems such as tar formation, biomass gasification has not yet been able to achieve its purpose. The purpose of this work was to study the catalytic activity of coal-bottom ash for fuel gas production and tar elimination. Effect of gasification parameters including reaction temperature (700–900 °C), equivalence ratio, EQR (0.15–0.3) and steam-to-biomass ratio, SBR (0.34–1.02) and catalyst loading (5.0–13 wt %) on gas distribution, lower heating value (LHV) of gas steam, tar content, gas yield and H₂/CO ratio was studied. The tar content remarkably decreased from 3.81 g/Nm³ to 0.97 g/Nm³ by increasing char-bottom ash from 5.0 wt% to 13.0 wt%. H₂/CO significantly increased from 1.12 to 1.54 as the char-bottom ash content in the fuel increased from 5.0 wt% to 13.0 wt%.