【作者】 王瀚平；

【导师】 苏俊林；

【作者基本信息】 吉林大学 ， 热能工程， 2012， 硕士

【摘要】 人类社会现在面临着巨大的能源及环境危机，能源消耗以及污染物的排放屡创新高。能源关系着一个国家的兴衰，能源问题已经成为各国争端的焦点。由于环境的污染近几年各种极端恶劣的天气接踵而至。发展可再生能源已经成为关系人类发展的重大问题。我国生物质能源发展起步晚，技术落后，并没有形成相应产业。借鉴国外经验，参照我国基本国情，在我国非常适合于发展生物质颗粒燃料。现阶段我国主要发展的是农作物秸秆类生物质颗粒燃料，这种生物质颗粒燃料有生物质燃料所具有的突出优点，但是其也具有明显的缺点，主要表现在燃烧过程中极容易发生积灰结渣阻碍燃烧的顺利进行，严重制约了生物质颗粒燃料的发展。本文针对生物质颗粒燃料容易积灰结渣这一问题，依据东北地区特点，选用玉米秸秆，大豆秸秆以及花生壳进行复合生物质颗粒燃料的研究，以解决玉米秸秆的灰分熔点过低问题。本文选用CaO，SiO2，MgO，Fe2O3，Al2O3以及长春当地粘土作为添加剂，以提高玉米秸秆颗粒燃料的灰分熔点，解决玉米秸秆燃烧过程中容易结块粘连的问题。并且通过热重试验对复合生物质颗粒燃料进行燃烧特性及燃烧动力学分析。其主要研究结果概括如下：1）复合生物质颗粒燃料的灰分熔融特性花生壳以及大豆秸秆这两种生物质其软化温度都很高，分别达1399℃以及1520℃，远远超过了玉米秸秆的1102℃。但是花生壳以及大豆秸秆分别与玉米秸秆混合燃料软化温度不高。试验研究发现，添加剂对于改善玉米秸秆的灰分熔融特性效果明显，MgO的含量达到3%时，玉米秸秆颗粒燃料灰分的软化温度（ST）达到1445℃，Al2O3的含量达到3%时，软化温度（ST）达到1450℃，CaO的含量为3%时，软化温度（ST）达到1355℃。2）复合生物质颗粒燃料的结渣特性在对复合生物质颗粒燃料进行模拟实际燃烧试验中发现，利用复合生物质颗粒燃料灰分的软化温度对生物质颗粒燃料进行灰熔融性评价，并不能准确地反映生物质颗粒燃料燃烧过程中的真实积灰结渣情况。运用模拟燃烧试验能够准确反映复合生物质颗粒燃料的结渣特性。玉米秸秆在900℃时已经表现出结渣倾向，在1000℃时已经完全结成硬块，而当MgO的含量达到3%时，复合生物质颗粒燃料在1200℃时也完全不结焦，其它添加剂在不同含量时亦能保证提高50~100℃。在对复合生物质颗粒燃料进行模拟实际燃烧试验中发现，利用复合生物质颗粒燃料灰分的软化温度对生物质颗粒燃料进行灰熔融性评价，并不能准确地反映生物质颗粒燃料燃烧过程中的真实积灰结渣情况。运用模拟燃烧试验能够准确反映复合生物质颗粒燃料的结渣特性。3）复合生物质颗粒燃料的燃烧特性利用O2及N2两种气氛进行热重试验，通过两种曲线进行结合分析，判断颗粒燃料的着火点，并分析研究认为复合生物质颗粒燃料的各种特性都要比玉米秸秆颗粒燃料的燃烧特性优异。4）复合生物质颗粒燃料的燃烧动力学特性生物质颗粒燃料的燃烧过程是一个非等温的过程，在对热重数据进行处理分析时，选用积分法的Coats-Redfern方法。利用Coats-Redfern方程进行线性拟合得到的回归方程求的“动力学三因子”中的表观活化能E以及频率因子A，通过分析认为Coats-Redfern方程能够很好的反应生物质颗粒燃料的燃烧过程。并且通过分析验证了复合生物质颗粒燃料燃烧特性的优异性。复合生物质颗粒燃料其结渣特性以及燃烧特性都要比玉米秸秆颗粒燃料好得多。优化配比得到的复合生物质颗粒燃料较好的解决了玉米秸秆燃烧过程中出现的结渣问题，并且研制的复合生物质颗粒燃料燃烧特性优越，对于复合生物质颗粒燃料的推广有积极作用，对于我国生物质能源的发展具有使用价值。更多还原

【Abstract】 Our society is facing huge energy and environmental crises now. Energyconsumption and discharge of pollutant are repeatedly break records. Energy affectsthe rise and fall of a country and energy problems has become the focus of all disputes.Extremely bad weathers come one after another in recent years due to theenvironmental pollution. The development of renewable energy sources has become abig issue that influences human progress.As a eximious and clean renewable energy,biomass has draw the attention of more and more countries. Biomass hasn’t formed acorresponding industry in China due to its late starting and backward technology.After learning from abroad and researching China’s basic conditions we find thatChina is propitious to develop biomass particle fuel. At present in China the mainbiomass particle fuel is that takes crops’ straw as material. This kind of biomassparticle fuel tents to produces slagging which hinder burning. And thus restricts thedevelopment of biomass particle fuel.This article aims to solve the problem of biomass’s slagging and ash fouling.According to the regional characteristics of northeast, corn straw, soybean straw andpeanut shells are used in the research of composite biomass particle fuel hoping tosolve the problem of corn straw ash’s low melting point. CaO，SiO2，MgO，Fe2O3，Al2O3and ChangChun’s local clay are taken as additives in order to heighten the cornstraw ash’s melting point and prevent agglomerate adhesion during burning process.Thermo-gravimetric experiment are conducted to analysis combustion characteristicand combustion kinetics of composite biomass particle fuel.1) Ash melting characteristics of composite biomass particle fuelsPeanut shells and soybean straw these two kinds of biomass the softeningtemperature are very high, up to139℃9and m ore than1520℃,far m ore than the corn straw1102℃. But peanut shells and soybean straw respectively with the cornstraw mixed fuel softening temperature is not high. Test study found, using additive toimprove corn stalk ash melting characteristics effect is obvious. The content of MgOreached3%, corn straw pellet fuel of ash softening temperature (ST) to144℃5, thecontent of Al2O3reached3%, softening temperature (ST) to1450℃, the content ofCaO reached3%, softening temperature (ST) to1355℃.2）Slagging characteristics of composite biomass particle fuelsSimulation of the actual combustion texts of composite biomass particle fuelsshows that evaluation of biomass particle fuel’s ash melting couldn’t reflect the realash slagging during its burning. Because the evaluation is based on compositebiomass particle fuel’s ash softening temperature. Application of simulation burningexperiment can accurately reflect the composite biomass particle fuel’s slaggingcharacteristics. Corn straw in900℃is show ing slagging tendency,in1000℃havebeen fully formed lumps. But when the content of MgO reached3%, compositebiomass pellet fuel in12℃00is com pletely not anti-coking, other additives indifferent content can also improve more than50to100℃.3) combustion characteristics of composite biomass particle fuelsO2and N2are used to conduct thermo-gravimetric experiment and produced twocurves. Particle fuel ignition is judged by combined analysis of this two curves.Research proved that all characteristics of composite biomass particle fuels are betterthan that of the corn straw particle fuels.4）Combustion kinetics characteristics of composite biomass particle fuelsCombustion process of composite biomass particle fuels is a non-isothermalprocess. The Coasts-Redfern method which belongs to integration is adopted todealing with the thermo-gravimetric data. The use of coats-Redfern equation areobtained by linear regression equation of the return of get "dynamic three factors" ofthe apparent activation energy E and frequency factor A. Based on analysis i thinkCoats-Redfern equation can give a good reflection on biomass particle fuelscombustion process. Analysis proved the excellent combustion characteristics of composite biomass particle fuels.The slagging and combusion characteristics of composite biomass particle fuelsare far better than corn straw particle fuel’s. Some composite biomass particle fuel hassolve the slagging problem during the corn straw combustion. The combustioncharacteristics of composite biomass particle fuel are extremely advantageous. Thisplays a positive role in spreading composite biomass fuel and has great significancefor the development of biomass energy in China.更多还原