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1.
松木预处理温度对生物油特性的影响   总被引:2,自引:0,他引:2  
通过螺旋反应器低温预处理除去松木中的半纤维素和水分,然后用预处理得到的固体残渣来快速热解制生物油。固体残渣的化学组成分析和红外光谱分析表明,由于木质素含量的增加和炭化反应的发生,生物油的产率降低、焦和不可冷凝气的产率增加。随着预处理温度的升高,生物油水分含量减少,高位热值增加,运动黏度增加,密度增加,pH值先升高后降低,固体颗粒物含量增加。核磁共振碳谱分析表明,生物油的脂肪碳含量减少,芳香碳含量增加,芳香度增加。  相似文献   

2.
通过螺旋反应器低温预处理除去松木中的半纤维素和水分,然后用预处理得到的固体残渣来快速热解制生物油.固体残渣的化学组成分析和红外光谱分析表明,由于木质素含量的增加和炭化反应的发生,生物油的产率降低、焦和不可冷凝气的产率增加.随着预处理温度的升高,生物油水分含量减少,高位热值增加,运动黏度增加,密度增加,pH值先升高后降低,固体颗粒物含量增加.核磁共振碳谱分析表明,生物油的脂肪碳含量减少,芳香碳含量增加,芳香度增加.  相似文献   

3.
生物油储存稳定性实验研究   总被引:1,自引:0,他引:1  
对松木和玉米芯快速热解制取的生物油进行储存稳定性实验,经过储存老化后的生物油黏度增大,水分含量和固体颗粒物含量增加,pH值、热值、密度无明显变化。通过GC-MS对储存前后生物油中主要组分进行定量分析表明,生物油经过储存后,羟基丙酮、乙酸、糠醛等主要组分的含量明显下降,而2-甲氧基苯酚、4-甲基-2-甲氧基-苯酚、4-甲基-苯酚的含量有所上升。核磁共振的碳谱分析表明,经过储存后生物油中甲氧基碳和双氧-烷基碳的含量降低,而芳基碳和不饱和碳的含量增大,生物油的芳香度有所提高。  相似文献   

4.
对松木和玉米芯快速热解制取的生物油进行储存稳定性实验,经过储存老化后的生物油黏度增大,水分含量和固体颗粒物含量增加,pH值、热值、密度无明显变化.通过GC-MS对储存前后生物油中主要组分进行定量分析表明,生物油经过储存后,羟基丙酮、乙酸、糠醛等主要组分的含量明显下降,而2-甲氧基苯酚、4-甲基-2-甲氧基-苯酚、4-甲基-苯酚的含量有所上升.核磁共振的碳谱分析表明,经过储存后生物油中甲氧基碳和双氧-烷基碳的含量降低,而芳基碳和不饱和碳的含量增大,生物油的芳香度有所提高.  相似文献   

5.
大气颗粒物中有机物色谱分析的样品制备技术   总被引:1,自引:0,他引:1  
郝亮  吴大朋  关亚风 《色谱》2014,32(9):906-912
大气颗粒物中有机物成分分析对深入研究大气颗粒物对人类健康、环境、气候、生态的影响,解析气溶胶来源,制定颗粒物控制相关法规,以及风险管理方法具有重要意义。由于颗粒物中的有机组分种类繁多,分析复杂,目前仅10%~20%的有机物得到了定性和定量分析。因此,大气细颗粒中有机物的分析已成为环境分析领域的优先发展方向。色谱是大气颗粒物中有机物分析的主要方法,而样品制备则是影响分析速度和精度的关键步骤。本文对颗粒物中有机组分色谱分析前的样品制备方法进行了综述,介绍了索氏提取、超声辅助提取、微波辅助提取、加压溶剂提取等溶剂提取方法以及热解吸提取方法,并重点介绍了这些方法在大气颗粒物样品处理中的应用,总结了各种方法的优缺点。  相似文献   

6.
王锐  高明洋  曹景沛 《应用化学》2022,39(2):289-297
研究碱/碱土金属(AAEM)对生物质的热解及其热解产物组成的影响规律,可为生物质热解特性研究和热解产物的高效利用提供重要的理论依据。本文以松木屑为原料,将原样进行酸洗,并对酸洗样分别用K、Ca、Na和Mg氯化盐溶液浸渍,在500℃和Ar气氛下对各样品进行快速热解,考察了4种金属离子对松木屑热解产物组成分布的影响规律;通过热重分析考察了各个样品的热解特性;通过对热解生物油的气相色谱/质谱(GC/MS)分析考察了快速热解的焦油成分。研究结果表明:AAEM对松木屑有明显的催化作用,AAEM的存在能够提高热解气体和固体的产率,降低热解焦油的产率;AAEM能够降低热解温度,使热解更加容易进行;快速热解的焦油成分主要有酚类、酮类、醛类、芳烃、醇类、脱水糖类、呋喃类以及酸类,AAEM显著影响焦油产物组成,特别是呋喃类和芳烃的含量会有所增加。本文为优化生物质的热解条件与提高热解生物油品质具有重要意义。  相似文献   

7.
不同种类生物油化学组成结构的对比研究   总被引:4,自引:2,他引:2  
利用气质联用和核磁共振光谱对不同种类生物油的化学组成结构进行了对比分析.气质联用分析表明,由于不同种类生物质原料化学组成的差异,导致不同种类生物油主要类别物质含量存在较大差别,有机酸含量较高的是蔗渣热解油,醛酮类物质含量较高的是蔗渣和稻草热解油,芳香类物质含量较高的是玉米芯和松木热解油,而脱水糖含量较高的是稻草和松木热...  相似文献   

8.
温度对稻草流化床快速热解液相产物影响的研究   总被引:2,自引:0,他引:2  
研究了温度对稻草流化床快速热解中热解油产率的影响,利用GC/MS、FT-IR考察了不同热解温度(300℃~600℃)及冷凝温度(22℃、-4.4℃)下,稻草经过热解所获得的热解油组成。结果表明,稻草在400℃热解温度下可获得最高热解油产率43.1%;冷凝温度对热解油的品质有较大影响,降低冷凝温度能够增加热解油中有机物的含量,热解油中的水分含量随之降低,同时热解油的热值也随之得到提高。  相似文献   

9.
将纸屑、甘蔗渣、木粉、谷壳、垃圾衍生燃料(RDF)五种废弃物进行燃烧,采集其烟气中可吸入颗粒物(PM10)样品并分析,获得了颗粒物中金属元素的质量分数和排放特性,并与其相应的原料和灰烬中的金属元素质量分数比较。结果显示,废弃物燃烧的颗粒物中金属元素的种类与燃烧的物料有关;纸屑的颗粒物中金属元素的质量分数最低,RDF的最高,其余三种生物质废弃物的质量分数较相近;在五种样品中,一些重金属的质量分数很高,比土壤中的质量分数高出很多倍;金属元素在灰烬和颗粒物中的分布情况与金属元素的性质密切相关,且在可吸入颗粒物上有明显的富集。  相似文献   

10.
生物油中有机化合物的分析与表征   总被引:1,自引:0,他引:1  
综述了目前国内外生物油成分分析的状况,重点介绍了红外光谱、核磁共振、质谱、气相色谱、高效液相色谱技术以及波谱-色谱联用技术在生物油有机小分子化合物结构表征方面的应用,评价了这些技术在生物油结构表征方面的作用和价值,并分析了生物油的理化特性及化学结构对检测分析产生的影响。此外,对生物油中的低聚糖和热解木质素等低聚物的分析检测研究也进行了介绍。最后,总结了波谱和色谱技术在生物油检测分析方面存在的主要问题,并对生物油中有机物检测与分析的发展趋势进行了展望。  相似文献   

11.
Fast pyrolysis of biomass is a promising process for the preparation of bio-oil dedicated to energy production. Inorganic species originally present in biomass are known to induce problems such as bio-oil instability or deposits and fouling. However the mechanisms of inorganic species release during biomass pyrolysis into the raw bio-oils still remain unclear. The present work focuses on the determination of inorganic distribution in the products from wheat straw and beech wood fast pyrolysis performed in a fluidized bed. More specifically, the bio-oils are fractionated by using a series of condensers. The results show that more than 60 wt.% of the inorganic content of the overall bio-oil is contained in the aerosols. Several possible interpretations for this observation are discussed. It is likely that the inorganics are transported within the aerosols droplets and solid particles which are recovered in the bio-oils, either by mechano-chemical processes, or by entrainment of submicron intermediate liquid compound formed in the first steps of biomass fast pyrolysis.  相似文献   

12.
Pyrolysis of sewage sludge in fluidized bed to produce bio-oil is under study as a useful way to valorise this waste. Sewage sludge is the waste produced in the wastewater treatment plants. Its composition may change due to the origin and to the non-standardized treatments in the wastewater treatment plants. The pyrolysis of three samples of anaerobically digested sewage sludge obtained from three different urban wastewater treatment plants was studied in this work. The organic and inorganic matter composition, and the volatile and ash content of these sewage sludge samples were different. The influence of these parameters on the pyrolysis product distribution and on some characteristics of these products was studied. It was determined that the ash content of the raw material had an enormous influence on the sewage sludge pyrolysis. An increase in the ash content of the sewage sludge caused an increase in the gas yield and a decrease in the liquid and the solid yield with the operational conditions studied. The increase of the volatile content of the sewage sludge samples caused an increase in the liquid yield. The H2 proportion was the most influenced non-condensable gas. It increased significantly with the ash content. The viscosity of the pyrolysis oils decreased when the ash content augmented. On the other hand, the water content depended on the organic composition of the sewage sludge samples. The chemical composition of the pyrolysis oils was also affected by the sewage sludge ash content above all the proportion of polyaromatic hydrocarbons and nitrogen-containing aromatic compounds. These compound groups increased with the augment of the sewage sludge ash content. The oxygen-containing aliphatic compounds and the steroids decreased with the ash content, although its proportion in the sewage sludge liquid was also influenced by the organic matter composition of the sewage sludge samples.  相似文献   

13.
Fossil fuels such as petroleum, charcoal, and natural gas sources are the main energy sources at present, but considering their natural limitation in availability and the fact that they are not renewable, there exists a growing need of developing bio-fuel production. Biomass has received considerable attention as a sustainable feedstock that can replace diminishing fossil fuels for the production of energy, especially for the transportation sector. JackfruitwasteisabundantinIndonesiamake itpotentiallyas one of thegreenrefineryfeedstockforthe manufacture ofbio-fuel.As intermediate of bio-fuel,jackfruitpeelsisprocessed intobio-oil. Pyrolysis, a thermochemical conversion process under oxygen-absent condition is an attractive way to convert biomass into bio- oil.In this study, the pyrolysis experiments were carried out ina fixed-bedreactor at a range of temperature of400-600 °C, heating rate range between 10-50 °C/min, and a range of nitrogen flow between 2-4litre/min. The aims of this work were to explore the effects of pyrolysis conditions and to identify the optimum condition for obtaining the highest bio-oil yield.The effect of nitrogen flow rate and heating rate on the yield of bio-oil were insignificant. The most important parameter in the bio-oil production was the temperature of the pyrolysis process.The yield of bio-oil initially increased with temperature (up to 550 °C) then further increase of temperature resulting in the decreased of bio-oil yield. Results showed that the highest bio-oil yield (52.6%)wasobtainedat 550 °C with nitrogen flow rate of 4L/min and heating rate of 50 °C/min. The thermal degradation of jackfruit peel was also studied using thermogravimetric analysis (TGA). Gas chromatography (GC-MS) was used to identify the organic fraction of bio-oil. The water content in the bio-oil product was determined by volumetric Karl-Fischer titration. The physicochemical properties of bio-oil produced from pyrolysis of jackfruit peels such as gross calorific value, pH, kinematic viscosity, density, sulfur content, ash content, pour point and flash point were determined and compared to ASTM standard of bio-oil (ASTM 7544).  相似文献   

14.
Vacuum pyrolysis of intruder plant biomasses   总被引:1,自引:0,他引:1  
Biomass from three invasive plant species of the Western Karoo region in South Africa, namely Kraalbos, Schotzbos and Asbos, was treated by vacuum pyrolysis. The influence of temperature, pyrolysis time, pressure and initial moisture content on the bio-oil and charcoal yields were investigated. Asbos with the largest ash content, 19.9 wt.%, gave chars with an ash content between 40 wt.% and 44 wt.% making it difficult to use commercially. Vacuum pyrolysis of Kraalbos resulted in producing a biochar with a HHV of 23.0-25.5 MJ/kg and an ash content of 13-19 wt.% which compared favourable with commercial charcoal. The bio-oils from both Kraalbos and Schotzbos showed promise as potential heating oil with a HHV of 21.6-26.9 MJ/kg. The tarry phase contained a number of phenolic compounds that can be separated and shows promise as a feedstock for upgrading. Finally ageing which acts on the lignocellulosic structure of biomasses decreased the charcoal and oil yields from the vacuum pyrolysis of intruder plants.  相似文献   

15.
以酸水解法从微拟球藻中提取的粗脂肪为原料,在管式裂解炉中考察不同热解温度下脂肪单组分的热解规律及对微拟球藻全组分各相产率及生物油性能的影响。利用热重分析仪分别考察粗脂肪及全组分的热失重特性,并求出相应的动力学参数。结果表明,脂肪热解能够提高全组分热解有机相产率并改善油品性能。随着温度的升高,粗脂肪与全组分热解后的有机相产率及油品性能的变化趋势相同,且生物油性能均在600℃时达到最佳。经热解,粗脂肪中含氧化合物含量降低,脂肪烃含量显著增加。对比全组分热解,粗脂肪热解后的油品脱氧率及氢、碳元素比例更高,因而增加全组分中脂肪的含量能够促进油品性能的进一步提高。对粗脂肪及全组分的热重数据进行计算,发现两者均满足二级化学反应机理,粗脂肪、全组分的活化能与指前因子分别为64.34 k J/mol与2.94×105min-1,48.13 k J/mol与2.96×103min-1。  相似文献   

16.
生物质热解油气化试验研究   总被引:14,自引:1,他引:14  
生物质是一种环境友好可再生资源,可以通过多种途径转化为液体燃料。生物质热解液化即是在缺氧状态下对生物质进行快速加热,然后再对热解产物进行快速冷凝,最后获得一种称为生物油的液体燃料的技术。该技术以及生物油的特点主要有:热解液化温度为500℃,远低于生物质热解气化所  相似文献   

17.
This article reports experimental results on fast pyrolysis of agricultural residues from cassava plantations, namely cassava rhizome (CR) and cassava stalk (CS), in a fluidised-bed fast pyrolysis reactor unit incorporated with a hot vapour filter. The objective of this research was to investigate the effects of reaction temperatures, biomass particle size and the use of simple hot vapour filtration on pyrolysis product yields and properties. Results showed that the optimum pyrolysis temperatures for CR and CS were 475 °C and 469 °C, which gave maximum bio-oil yields of 69.1 wt% and 61.4 wt% on dry biomass basis, respectively. The optimum particle size for bio-oil production in this study was 250–425 μm. The use of the hot filter led to a reduction of 6–7 wt% of bio-oil yield. Nevertheless, the filtered bio-oils appeared to have a better quality in terms of initial viscosity, solids content, ash content and stability.  相似文献   

18.
This study was aimed to understand the physical and chemical properties of pyrolytic bio-oils produced from microwave pyrolysis of corn stover regarding their potential use as gas turbine and home heating fuels. The ash content, solids content, pH, heating value, minerals, elemental ratio, moisture content, and viscosity of the bio-oils were determined. The water content was approx 15.2 wt%, solids content 0.22 wt%, alkali metal content 12 parts per million, dynamic viscosity 185 mPa.s at 40 degrees C, and gross high heating value 17.5 MJ/kg for a typical bio-oil produced. Our aging tests showed that the viscosity and water content increased and phase separation occurred during the storage at different temperatures. Adding methanol and/or ethanol to the bio-oils reduced the viscosity and slowed down the increase in viscosity and water content during the storage. Blending of methanol or ethanol with the bio-oils may be a simple and cost-effective approach to making the pyrolytic bio-oils into a stable gas turbine or home heating fuels.  相似文献   

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