程序升温下秸秆类生物质燃料热解规律

用热重分析仪对秸秆类生物质的热解行为进行了热重分析（TG）和差分热分析（DTG）。试验中利用程序升温法对物料进行加热升温，加速率分别为10K/min，２０Ｋ／min和３０K/min;加热终温为1173K，样品料径为250－1000um，高纯氮气做保护气，通过对TC，DTG曲线分析，研究了加热速度，温度，加热时间等对热过程的影响，给出了热解反应动力学参数，结论对秸秆类生物的再利用技术研究和装置优化有重要的指导价值。     

生物质加压热重分析研究

对两种生物质木屑和松针进行了不同压力和升温速率下的热重分析试验，通过生物质热重失重率（TG）和失重速率（DTG）曲线，获得了相关热解特性参数，提出了生物质的挥发分综合释放特性指数D．并通过热分析数学方法求取了生物质热解动力学参数．试验结果表明，氮气气氛中，木屑与松针常压和增压下主要热解阶段可认为两段一级反应；热解压力的提高，将延迟生物质挥发分初析温度和DTG峰值温度，降低最大析出率和DTG峰值，生物质的挥发分综合释放特性指数D也减小，增加了生物质挥发分的析出难度，并改变了热解反应活化能和频率因子．同一压力下，提高热解升温速率，生物质综合特性指数D将增加．     

废物衍生燃料_RDF_加压热解特性及其动力学研究

利用加压热重分析仪对城市固体废弃物衍生燃料（RDF）中厨余物等典型有机组份进行了加压热分析研究，实验载气为高纯氮气，加热速率为20K/min，终温773K。通过对热重（TG）、微分热量（DTG）曲线的深入分析，得出了加压条件下RDF中几种典型有机组份的热解反应动力学参数，并提出相应的热解机理。     

玉米秸秆热解规律的试验研究

用热重分析法对玉米秸秆的热解规律进行了研究，分析了玉米秸秆样品在不同升温速率（5，10，20，30℃／min）、不同温度（250，300，350℃）恒温加热2h条件下热解的试验结果，发现样品的非等温失重过程由脱水、保持、剧烈失重和缓慢失重4个阶段组成，并且在相同条件下，样品的质量对玉米秸秆热解有一定的影响。在恒温热解过程中，在不同的恒温温度条件下，秸秆失重曲线形态基本相似，但在300℃条件下，恒温热解的热重曲线与250，350℃条件下恒温热解的热重曲线相比较为平缓。     

生物质热解与燃烧特性试验研究

对稻秆的热解特性和燃烧特性进行了热重分析(TG)和差分热重分析(DTG)研究.热解试验中采用高纯氮气作为保护气体.采用升温速率为15 ℃/min、40 ℃/min、100 ℃/min,加热终温800 ℃.燃烧试验在干燥热空气气氛下进行,升温速率40 ℃/min.通过对稻秆热解和燃烧特性的TG和DTG曲线,深入分析稻秆热解、燃烧的基本过程和基本特征.并通过动力学分析获得了不同升温速率下热解和燃烧的活化能和频率因子动力学参数.     

木质类生物质的热重分析研究

在常压热重分析仪和加压热重分析仪上对木屑进行了热解实验，利用热重分析法对其热解行为特性和动力学规律进行了分析．得到了升温速率、压力等因素对木屑热解过程的影响规律。实验表明：常压下，随着升温速率的增加，反应激烈程度增加；与常压相比，加压状态下，活化能明显减小；随着热解压力的提高，挥发分初析温度和DTG峰值温度升高，最大失重速率减小；活化能E与频率因子A之间存在动力学补偿效应，升温速率不变，改变压力或者压力不变，改变升温速率，得到的利、偿效应表达式不同。     

草类生物质热解特性及动力学的对比研究

我国长江中下游地区有大面积分布的芒属、芦苇、狼尾草,研究很少,应用少.为草类生物质能的开发与利用提供又一途径.对芒属、芦苇、狼尾草进行常压热重分析,同时与常见的稻草相比较,通过生物质热解失重率(TG)和失重速率(DTG)曲线,获得相关热解特性参数,采用生物质挥发分综合释放指数(D),并通过热分析数学方法求取生物质热解动力学参数.试验结果表明:草类生物质热解过程可以分为4个阶段,在563 K附近存在一个肩峰,失重都集中在460 K～673 K.挥发分综合释放指数则芒属>稻草>狼尾草>芦苇,活化能则芒属>稻草>狼尾草>芦苇,固体剩余物则芒属>狼尾草>稻草>芦苇,所以总体上看芒属的热解稳定性相对较差,芦苇的热解稳定性较好,同时采用二级反应动力学模型由Coats-Redfern法求的相应得活化能和频率因子.也为今后更好、更合理高效的利用这些草类提供实验数.     

杨木屑热解过程及动力学研究

运用热重分析法研究了氮气下杨木屑的热解过程.在不同的升温速度(5、15、30℃/min)下,对热解TG、DTG、DSC曲线分析,得出杨木屑热解分干燥、预热解、热解和煅烧4个阶段,并且热解随着升温速度的提高出现了热滞后现象.最后通过比较1、1.5、2、3级反应动力学模型,确定1级反应为杨木屑热解的动力学模型,并求出了热解反应的活化能和频率因子.     

秸秆类生物质闪速热解规律

为了研究闪速加热条件下生物质的热解挥发特性，设计了等离子体加热高温层流炉作为实验设备。用有代表意义的玉米秸秆粉末，在该层流炉上进行了4个加热温度（800K，850K，900K，950K）的热解实验研究。得出了不同加热温度和停留时间下玉米秸秆粉末热解的实验数据；根据这些实验数据和Arrhenius一级反应动力学模型方程，分析得出相应的化学动力学参数：表观频率因子和表观活化能。研究发现，在闪速加热条件下，玉米秸秆粉末的热解化学动力学参数并不随工况的变化而改变，具有统一的公式。用这个模型进行了相应工况的理论计算，得到了挥发份随停留时间和反应温度变化的曲线，并与实验结果进行了比较。结果表明，实验值和模型计算预测值有很好的一致性，所得的模型和相应的动力学参数具有广泛适用性。本项研究结论对秸秆类生物质的闪速热解规律的研究和热解装置的优化设计有重要的指导意义。     

不同条件下玉米秸秆热解规律实验研究

用热重分析法对玉米秸秆的热解规律进行了研究。分析了玉米秸秆样品在不同升温速率（5，10，20，30℃／min）和不同温度（200，250，300，350℃）条件下恒温2h热解的实验结果，发现样品的非等温失重过程由脱水、保持、剧烈失重和缓慢失重4个阶段组成，并且在相同奈件下样品的质量对玉米秸秆热解有一定的影响：在恒温热解过程中，不同的恒温温度条件下其失重曲线形态基本相似，但在300℃条件下恒温热解的热重曲线与250℃、350℃条件下恒温热解的热重曲线相比则较为平缓。上述的研究结果为玉米秸秆的舍理利用提供了一定的理论基础．     

Bio-fuels from Agricutural Residues

Abstract

Bio-fuels, such as bio-oil, bio-char, and bio-gas, can be obtained from agricultural residues. Agricultural residues are potential renewable energy resources such as biogas from anaerobic digestion, bio-oil from pyrolysis, and bio-char from carbonization and slow pyrolysis processes. Pyrolysis process of agricultural residues are the most common and convenient methods for conversion into bio-oil and bio-char. When the pyrolysis temperature increased, the bio-char yield decreased. The bio-char yield increased with increasing particle size of the sample. The yield of bio-oil from pyrolysis of the samples increased with temperature. Anaerobic biogas production is an effective process for conversion of a broad variety of agricultural biomass to methane to substitute natural gas and medium calorific value gases.     

糠醛渣热解特性及其动力学研究

生物质热解是未来最有前途的可再生能源形式之一，为优化参数和改进设备，在不同升温速率下对糠醛渣的热解特性进行热重分析实验研究。实验采用美国Perkin Elmer公司生产的Pyris 1TGA热重分析仪，载气为纯度99．9％的氮气。结果表明糠醛渣热解随温度升高具有阶段性，表现了糠醛渣热解的复杂性。通过对不同升温速率下的失重曲线对比表明，升温速率对热解失重有显著影响。最后根据实验数据建立了热解动力学模型，分别用积分法和微分法对热解动力学参数进行求解。     

生物质热解的TGA-FTIR分析

基于TGA-FTIR联用技术,在线分析研究稻壳、稻秆及麦秆3种典型生物质在不同升温速率下的热解特性.分析生物质种类及升温速率对生物质的热解动力学参数及热解产物的影响.研究表明:由于生物质组成不同,其热失重特性也不同,生物质热解反应的活化能较低,为40～60 kJ·mol-1;红外分析表明试验用生物质热解过程中产物的析出规律相似,热解初始阶段先析出游离水,随后发生解聚和脱水反应,生成各种烃类、醇类、醛类和酸类等物质.随后,这些大分子物质又二次降解为一氧化碳为主的气体产物.     

Product distribution from solar pyrolysis of agricultural and forestry biomass residues

Solar pyrolysis of pine sawdust, peach pit, grape stalk and grape marc was conducted in a lab-scale solar reactor for producing fuel gas from these agricultural and forestry by-products. For each type of biomass, whose lignocellulose components vary, the investigated parameters were the final temperature (in the range 800°C–2000 °C) and the heating rates (in the range 10–150 °C/s) under a constant sweep gas flow rate of 6 NL/min. The parameter influence on the pyrolysis product distribution and syngas composition was studied. The experimental results indicate that the gas yield generally increases with the temperature and heating rate for the various types of biomass residues, whereas the liquid yield progresses oppositely. Gas yield as high as 63.5wt% was obtained from pine sawdust pyrolyzed at a final temperature of 2000 °C and heating rate of 50 °C/s. This gas can be further utilized for power generation, heat or transportable fuel production.     

Potential evolution of Turkish agricultural residues as bio-gas,bio-char and bio-oil sources

A study has been conducted to evaluate the potential power production from the pyrolysis for bio-oil and bio-char, and anaerobic digestion (for bio-gas), of agricultural residues in Turkey. Agricultural residues are potential renewable energy resources such as bio-gas from anaerobic digestion, bio-oil from pyrolysis, and bio-char from carbonization and slow pyrolysis processes. Anaerobic bio-gas production is an effective process for conversion of a broad variety of agricultural biomass to methane to substitute natural gas and medium calorific value gases. When the pyrolysis temperature increased the bio-char yield decreased. The bio-char yield increased with increasing particle size of the sample. Thermochemical conversion processes of biomass are the most common and convenient methods for conversion into energy. Among the processes of energy production from biomass, pyrolysis is the most popular thermal conversion process.     

Production and Characterization of Bio-Chars from Biomass via Pyrolysis

This article deals with slow pyrolysis of oak wood and agricultural residues such as hazelnut shell and wheat straw at high temperature (950–1250 K) in a cylindrical reactor. The aim of this work is to study the effect of the treatment conditions such as temperature, particle size, and lignin and inorganic matter contents on bio-char yield and reactivity. When the pyrolysis temperature increased, the bio-char yield decreased. A high temperature and smaller particles increase the heating rate resulting in a decreased bio-char yield. The higher lignin content in hazelnut shell results in a higher bio-char yield in comparison with oak wood and wheat straw. Bio-chars from hazelnut shell and wheat straw are more reactive in gasification than bio-chars from oak wood because of the higher ash content. The bio-char obtained are carbon rich, with high heating value and relatively pollution-free potential solid biofuel.     

玉米秆与玉米芯热重分析

用热重分析仪对玉米秆和玉米芯的热解和燃烧动力学特性进行了研究,通过热解试验发现玉米秆和玉米芯挥发分的析出基本在一个阶段内完成,而燃烧试验研究表明燃烧过程主要由挥发分的燃烧和焦碳及残余挥发分的燃烧这两个阶段组成。上述结果为进一步有效利用玉米秸秆提供了一定的理论基础。     

纤维素催化热解定向调控制取不含氧烃类液体燃料

为了将生物质能高效转化为高品位不含氧的液体燃料,以纤维素为例,研究了以催化热解方式将热解产物转化为芳香烃类液体燃料的过程.实验发现,纤维素热解产生的含氧有机小分子,可以通过催化热解的形式高效转化为不含氧的芳香烃类液体.催化剂采用HZSM-5(23)、催化剂原料质量比例为5∶1、热解温度为650℃、升温速率为10000 K/s的工况为纤维素催化热解的最佳工况,单环芳烃、多环芳烃产率分别为9.90%和12.91%,总芳香烃类产率为22.81%.热解温度提升至650℃前,更高的热解温度能获得更高的芳香烃产率.继续提高热解温度,单环芳烃、多环芳烃分子间还可能进一步发生聚合反应,最终产生积碳.同时本文也提出了一种可行的纤维素催化热解中的反应途径,与本文实验结果较为匹配.     

Fractionation of flash pyrolysis condensates by staged condensation

The utilization of condensates from flash pyrolysis is challenging due to several unwanted properties. The condensates consist of a mixture of many high value compounds, but each of them is only contained in a low concentration. As additional challenge instantaneous phase separation into an aqueous and a sludgy heavy organic phase takes place, if agricultural residues like barley straw are used as raw material for pyrolysis. A separation by means of distillation is not possible as the compounds undergo polymerization reactions when exposed to higher temperature. A different approach for separation based on boiling temperature is staged condensation of original vapors. Ablative flash pyrolysis is performed in a laboratory. The pyrolysis vapors are condensed in either two or three stages, each composed of a double-effect cooler followed by an electrostatic precipitator. The higher boiling fractions are low in water and acid and show a high heating value. This makes it applicable as sulfur-free bunker fuel and replacement of heavy fuel oil. It can also serve as fuel for gasification plants for the production of either combined heat and power or 2nd generation biofuels. Depending on condensation configuration the first fractions can also be utilized for the production of rigid polyurethane foams or phenolic resins. The last fraction obtained at the lowest cooling temperature mainly consists of water and acids. The production of pure acetic acid seems economically feasible and utilization in agricultural biogas plants is also possible. This is proved by batch fermentation experiments in the biological laboratories.