【作者】 王琦；

【导师】 骆仲泱； 王勤辉； 岑可法；

【作者基本信息】 浙江大学 ， 工程热物理， 2008， 博士

【摘要】 生物质快速热裂解技术容易实现连续化生产和工业化应用,可将生物质转化为液体燃料潜在替代品——生物油,成为当今世界可再生能源发展领域中的前沿技术之一。然而影响热裂解的因素很多,产物生物油难以直接利用,都成为制约生物质快速热裂解技术商业化发展的主要瓶颈。基于此本文结合国家重点基础研究发展计划项目和国家自然科学基金项目,对生物质快速热裂解制取生物油及其产物的后续应用进行了较为系统的研究。生物质原料的种类直接影响热裂解液化最终的产物分布,综合我国生物质资源的种类和分布特点与经济可行性的考虑,选取了四类生物质中7种典型生物质物料作为研究对象,通过元素分析、工业分析、组分分析、热裂解动力学分析和热重红外联用分析等方法,对不同种类生物质自身的物理化学性质进行剖析,并研究其在惰性气氛下的热裂解行为,对热裂解产物进行了初步判断和分析。在给料量5Kg/h的小型生物质流化床快速热裂解试验系统上研究了不同喷淋介质对生物油产率和性质的影响,L型异构烷烃是一种比较理想的喷淋介质,与生物油掺混后迅速分层并对生物油成分影响较小,同时喷淋冷凝可以在一定程度上提高生物油的产率。利用流化床快速热裂解试验系统研究得出了生物质快速热裂解过程中反应条件和生物质种类对生物油产率的影响规律,并进一步对生物质热裂解产物的特性进行了分析,在对生物油进行理化特性分析的基础上,利用分子蒸馏技术对生物油进行分馏预处理,分析了生物油的蒸馏特性。同时对生物质热裂解生成的焦炭的物理性质和自身的孔隙结构进行了分析,结果表明生物质热裂解焦炭本身已经具有初步的孔隙结构,具有制备活性炭的条件。生物油与柴油乳化合成乳化燃料是近期促成生物油部分替代动力燃料的有效方法,通过对生物油模型化合物的乳化研究开展了乳化燃料配方的初步探索,进一步试验确定了适合生物油乳化的乳化剂配方,并分析了生物油保存时间和收集方式等因素对乳化效果的影响,同时对不同种类生物质热裂解生物油在较佳乳化剂配方下进行了乳化试验,分析了乳化燃料的乳化性能以及相应的理化性质。在试验研究的基础上,对乳化燃料进行了拟三元相图模拟与燃烧特性模拟计算,为生物油乳化燃料的经济利用和优化乳化配方提供一定的参考。更多还原

【Abstract】 Biomass fast pyrolysis technology is promising to realize the continuous produc tion and industrial applications,and capable to convert biomass into bio-oil that mi ght be a substitute to the liquid fuels,and thus become one of the frontier technol ogies in the world’s development of renewable energy.However,various impact fac tors on pyrolysis,as well as the limitations in the direct utilization of crude bio-oil, are the primary issues that restrict the commercialization of biomass fast pyrolysis technology.On this basis,and supported by the Basic Research Program of China and National Natural Science Foundations,an integrated research on the production and utilization of bio-oil from biomass fast pyrolysis was presented in this thesis.The species of biomass feedstock influenced the distribution of liquid pyrolysis products directly.Considering the species and distribution of biomass resources in China and the economic feasibility,seven different biomass materials belonging to f our species were selected as the research objects.A series of testing methods,such as elemental and industrial analysis,compositional analysis,thermogravimetric anal ysis,thermogravimetric-Fourier transform infrared spectrometry analysis,were carried out to achieve the physical and chemical properties of different biomass materials. The pyrolysis behavior at inert atmosphere was studied,and the pyrolysis products were identified preliminarily.The influence of different spray mediums on the yield and quality of bio-oil w as investigated in a 5kg/h biomass fast pyrolysis fluidized-bed reactor.L-isopar was a perfect spray medium,which would come into different layers with bio-oil rapid ly after mixed and not impact the composition of bio-oil.Moreover the spray cond ensation improved the bio-oil yield to some extent.On the fluidized-bed pyrolysis s ystem the influence of operating conditions and the biomass species on the bio-oil yield was achieved,and the properties of the pyrolysis products were analyzed furt her.Based on the analysis of physical and chemical characteristics,the bio-oil was pre-separated by molecular distillation,and the properties of bio-oil distillates were analyzed.The physical properties and the porosity structure of biomass pyrolysis ch ar were studied.It was indicated that the char generated during biomass pyrolysis h ad the primary porosity structure,available for the production of active carbon.In the near future emulsification of bio-oil together with diesel to produce emu lsified fuels is an effective way to use bio-oil as an alternative fuel.The formulas of emulsified fuels were explored firstly by studying the emulsification of bio-oil m odel compounds.The appropriate formulas for bio-oil emulsification were determine d by further experimental research,and the influences of storing periods and collect ion ways of bio-oil on the emulsification performance were analyzed as well.Differ ent biomass pyrolysis oils were emulsified by the optimized emulsifier formula.The emulsification performance and physical-chemical properties of the emulsified fuels were analyzed.Based on the experimental results,pseudo-ternary phase diagram of the emulsified fuels was drawn,and their combustion characteristics were numerica lly simulated,which were helpful to the utilization of bio-oil emulsified fuels econo mically and the optimization of emulsifier formulas.更多还原