低变质煤与塑料微波共热解研究

进行了微波加热条件下陕北孙家岔低变质煤与塑料共热解的实验研究.结果表明:随着塑料添加比例的增大,兰炭产率逐渐降低,焦油产率明显提高.当塑料加入量为10%时,焦油产率可达到17%,同时煤气中H2,CO和CH4的含量显著增加,分别可达到44.21%,18.75%和21.97%.塑料的加入有利于提高焦油的回收率,优化热解煤气成分,对煤气的进一步综合利用具有重要意义.     

煤与稻壳共热解热重分析及动力学

利用热重分析仪对长焰煤和稻壳分别单独及按不同掺混比例进行热质量损失实验研究。通过比较煤与稻壳共热解热质量损失曲线和计算得到的理论曲线发现,添加稻壳对共热解过程有促进作用,在不同的稻壳掺混比例下,共热解过程质量损失率和最大质量损失速率均较理论值有不同程度的增大,推测稻壳掺混对共热解存在促进作用,促进作用与稻壳掺混比例不成线性关系。对煤与稻壳及共热解过程进行动力学分析,获得了反应活化能和频率因子,分析计算热解动力学参数表明共热解过程存在动力学补偿效应。     

煤与杜氏盐藻共热解过程分析及动力学研究

在氮气气氛中,利用热重分析对煤与杜氏盐藻及其混合物的热解特性进行了研究,考察了煤与杜氏盐藻不同掺混比例对热解过程的影响,并研究了共热解动力学.结果表明,煤与杜氏盐藻共热解特性并不是两者单独热解特性的简单叠加,在200～500℃范围内两者之间存在明显的协同效应,其相对值高达28％.煤和杜氏盐藻单独热解均可分3个阶段,由于固定碳和灰分含量高,煤在相同热解阶段的失重率较杜氏盐藻低.动力学分析结果表明,以峰值温度为分界点,采用2个连续一级反应模型与实验数据拟合效果良好,计算得到共热解过程中的活化能和指前因子分别为16.06～28.20 kJ/mol和0.42～16.82 min-1;活化能与指前因子的对数之间具有良好线性关系.     

煤与废塑料共热解特性研究进展

煤与塑料共热解既能回收废塑料中的碳氢资源,又可以实现废塑料的资源无害化处理,是一种很有前景的废塑料资源化回收利用方式。本文概述了煤与塑料共热解的热解特性及其产物性质,分析了煤与塑料共热解的机理及共热解过程中氯的迁移规律,简要介绍了煤和塑料的不同混合方式及其对共热解特性的影响。文中指出煤与塑料共热解具有明显的增油减水效应,在煤热解过程中添加一定量的废塑料不仅可以改善焦油品质,同时对热解半焦的结构和反应性也有一定的影响,因此煤-塑料共热解是一种绿色高效资源化的废塑料处理方式,对于废塑料循环利用、解决白色污染问题及提高煤炭利用率具有重要意义。     

整体式钒催化剂制备中塑芯材料对热加工性能的影响

整体式钒催化剂是一种新型催化剂,其内部交联通道通过预埋塑芯并煅烧去除的方法制备。塑芯的引入改变了钒催化剂的制备流程,尤其是热加工程序。通过测定钒催化剂热膨胀率、热重、差热和活性等方法,研究了塑料与钒催化剂共烧过程的共热膨胀和失重效应及对钒催化剂性能的影响。结果表明,在煅烧温度段300～400 ℃,煅烧升温速率应控制在15 ℃·h^－1,而塑芯的烧除过程不影响催化剂本身活性。     

生物质与废塑料共热解的研究进展

文章介绍了国内外生物质热解、废塑料热解以及生物质与废塑料共热解的发展现状与趋势,概述了我国生物质能源与废塑料共热解的潜力。对生物质和废塑料共热解进行了展望,并指出了生物质和废塑料共热解研究的发展战略。     

纸塑铝复合包装材料各组分共热解行为研究

以用甲酸分离枕型利乐包所得的纸、聚乙烯、铝作为实验材料,采用热重红外联用(TG-FTIR)分析技术,研究了各组分在热解过程中的协同作用,以探索纸塑铝复合包装各组分共热解机理,为实现废弃利乐包材料的资源化利用提供科学参考和实验依据。结果表明:共热解时纸和聚乙烯之间存在协同作用,在失重峰位置表现得尤为明显;铝在共热解时具有一定的催化作用,在反应的不同阶段起到了相应的促进或者抑制热解的作用。     

木质素与高密度聚乙烯共热解特性研究

生物质与塑料共热解是一种非常有效的生物质利用方法之一,但由于生物质结构的复杂性,共热解过程的机理尚不明晰。木质素是生物质的主要组分之一,本文通过热重-质谱联用仪和裂解器-气相色谱质谱仪研究其与高密度聚乙烯共热解过程,获取共热解特性及热解产物分布特性,以揭示共热解过程机制。结果显示,木质素与高密度聚乙烯共热解过程存在协同效应,使得热解失重速率加快,热解固体残渣含量减少。共热解过程有利于CH₄、H₂O、CO和C₂H₄的生成,抑制CO₂的生成。同时,酚类、醇类和糖类等含氧化合物产量减少,烷烃和烯烃类化合物产量增加。结果表明,共热解过程会发生氢转移现象,氢与木质素衍生热解产物结合发生反应,从而抑制含氧化合物的生成,促进烷烃类和烯烃类化合物生成。     

Co-pyrolysis characteristics of polysaccharides-cellulose and the co-pyrolyzed compound distributions over two kinds of zeolite catalysts

Co-pyrolysis characteristics of soluble polysaccharides-cellulose were investigated through thermogravimetric analysis (TGA), kinetic analysis, analytical pyrolyser coupled with gas chromatograph-mass spectrometer (Py-GC/MS) and subsequent density functional theory (DFT). Results from TGA and differential thermogravimetric analysis (DTG) analyses indicated that there were synergistic effects in the polysaccharides-cellulose (PS-CE) blends pyrolysis process. Surprisingly in co-pyrolysis process from Py-GC/MS analysis, the furans were suppressed, while the anhydrosugars were increased. The DFT calculation showed that free radicals pyrolyzed from soluble polysaccharides could suppress the ring-opening reaction of D-glucopyranose. The co-pyrolyzed chemical compound distribution over the catalysts (MCM-41, ZSM-5 and their mixtures) was also detected through Py-GC/MS analysis. Both the zeolites showed high selectivity for 5-methyl-2-furaldehyde and 2-furaldehyde. The two kinds of zeolites could induce the generation of furans but suppress the production of anhydrosugars, which was the opposite effect of the co-pyrolysis of PS-CE.     

A review on co-pyrolysis of coal and oil shale to produce coke

It has become the top priority for coking industry to rationally use and enlarge coking coal resources because of the shortage of the resources. This review focuses on the potential utilization of oil shale (OS) as a feedstock for coal-blending coking, in which the initial and basic step is pyrolysis. However, OS has a high ash content. If such OS is directly used for coal-blending coking, the coke product will not meet market demand. Therefore, this review firstly summarizes separation and beneficiation techniques for organic matter in OS, and provides an overview on coal and OS pyrolysis through several viewpoints (e.g., pyrolysis process, phenomena, and products). Then the exploratory studies on co-pyrolysis of coal with OS, including co-pyrolysis phenomena and process mechanism, are discussed. Finally, co-pyrolysis of different ranks of coals with OS in terms of coal-blending coking, where further research deserves to be performed, is suggested.