城市生活垃圾热解/燃烧特性的实验研究

对城市生活垃圾中的6种典型单一组分及两两混合组分进行热重特性试验，先通氮气进行热解反应，当温度达到550℃时，再通氧气模拟空气进行燃烧反应。将热解和燃烧反应特性在同一曲线图中表现出来，分阶段求取反应动力学函数方程及动力学参数活化能E、频率因子A，进而为建立热解／燃烧综合模型提供基础依据；验证了混合物质的热解／燃烧特性可以用单组分物质的热解-燃烧特性的叠加来表示，除某些混合试样的组分之间会表现出一些相互影响，但这种影响并不强。     

中国城市垃圾典型组分热解特性及动力学研究

对城市生活垃圾中的8种典型组分进行了热重分析实验,提出热解指数来表征垃圾的热解特性,热解指数越高,垃圾越容易热解.结果表明,提高加热速率有助于增大热解指数;相同加热速率和粒度条件下,8种垃圾组分的热解能力依次为:废塑料、废纸张、废皮革、瓜皮类、化纤、落叶、植物类厨余和废橡胶,其中废塑料的热解指数远远大于其它7种组分.用积分法对热解实验数据进行处理,得出反应动力学参数及反应速率控制方程,从而得到相应工况和温度区间下的动力学模型.可以看出,垃圾组分不同,其反应机理可能不同,相对应的热解动力学模型也不同.     

分布活化能模型在垃圾热解/气化动力学研究中的应用

采用热重分析仪,对我国城市生活垃圾典型有机混合物(MMSW)的热解和气化特性进行了研究,并用分布活化能模型对TG-DTG曲线进行了动力学分析.试验表明:MMSW失重过程分为厨余中淀粉热解、厨余中脂肪分解、纸类纤维素热解和聚乙烯分解4个过程,并存在3种有机组分的相互作用;在相同失重率下,气化反应活化能值高于热解反应活化能值;整个反应过程中,热解反应活化能分布较窄,而气化反应活化能分布在相对较宽的范围内.     

不同生活垃圾组分热解炭化特性与热解焦傅里叶红外光谱表征

对城市生活垃圾(MSW)中6种有机组分进行热解炭化和热解焦傅里叶红外光谱(FTIR)表征。实验结果表明:MSW不同有机组分热解焦产率各不相同,热解焦产率由高到低依次为纸张 > 厨余 > 木屑 > 橡胶 > 织物 > 塑料,办公废纸慢速热解时热解焦产率高达37.50%,聚乙烯(PE)快速热解时热解焦产率仅为3.20%;慢速升温时热解焦产率普遍高于快速升温热解焦产率;MSW有机组分经热解炭化后,羟基(OH)、羰基(C=O)等官能团含量减少,烯属烃及芳香类C=C键含量增加;升温速率越慢,芳香类C=C键含量越高,芳香化程度越高。     

基于Weibull混合模型的生物质热解动力学研究

该研究选取中国产量较高的3种农作物水稻、油菜和棉花的秸秆作为研究对象,采用Weibull混合模型对稻秆、油菜秆和棉秆进行热解动力学解析。结果表明,稻秆、油菜秆和棉秆的热解动力学子过程可分为3个过程:水分蒸发,热解挥发分析出和热解炭化;Weibull混合模型可很好的描述3种物料的热解挥发分析出过程;Weibull混合模型可将生物质热解动力学过程分解为其主要组分纤维素、半纤维素和木质素的热解子过程。研究结果有助于后续生物质热解机理的研究。     

热带城市垃圾典型组分的热解特性研究

对热带城市垃圾的几种典型组分进行了热解实验，得到了它们的失重曲线，通过对失重曲线进行分析，得到了这几种典型组分的热解规律，并通过建立热解动力学模型，求出了其中两种组分的活化能E和频率因子A。     

芦苇热解过程的动力学模型研究

采用热重实验对芦苇的热解特性进行了研究,并采用2种动力学模型对不同升温速率(10、20、30℃/min)下芦苇热解过程进行了动力学研究。实验结果表明,芦苇热解主要分为水分析出阶段(30~120℃)、解聚过程阶段(120~237℃)、挥发分脱除阶段(237~369℃)及无机物和残留有机物的分解阶段(369~682℃),并且随着升温速率的增大,热解温度特征点向高温侧偏移。模型计算结果表明,n级单一反应模型在n=1时拟合程度最高,主要遵循一级反应,活化能分别为30.70、34.60、33.01 k J/mol;分布式活化能模型计算得出的活化能处于30~116 k J/mol之间。通过对比2种模型的计算结果,得出分布式活化能模型能更好地反映芦苇的热解过程。     

垃圾低温热解的特性模拟及过程优化

文中基于化工流程模拟软件Aspen Plus,选取城市生活垃圾中的典型组分塑料和橡胶,对其建立低温热解反应模型,研究结果表明,在温度400℃时反应结果最为良好,在该温度下,N2与不可燃气体的混合有最优热解过程,同时塑料与橡胶混合模拟也得到最佳混合比例。     

医疗废物典型组分在回转窑内的热解研究

针对医疗废物的无害化处置问题，对四种典型医疗废物在回转窑实验台上进行了有机组分的试验研究，分析了各物料的热解过程，确定了各自的产物分布、产气变化趋势以及热解终温的影响等，为医疗废物的处置、利用提供参考依据。     

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。     

等温环境下垃圾热解影响因素分析

在自行设计的、可以在等温环境下进行大物料量的热重实验装置上，对三种垃圾样品聚乙烯、自行车外胎以及带字打印纸进行了一系列热解研究，着重分析了不同环境温度、不同样品量、不同外在水分以及不同样品混合这四方面因素对垃圾热解特性的影响。     

Thermal – Catalytic cracking of real MSW into Bio-Crude Oil

The thermal decomposition method has been able to convert of real municipal solid waste (MSW) into Bio-Crude Oil (BCO) which is mainly contained hydrocarbon fuel such as light oil (gasoline) and heavy oil (diesel). By this method, sustainable MSW management and energy problem can be considered. Hence, this research was conducted the pyrolysis experimental to BCO production from the real MSW under thermal and catalytic pyrolysis at 400 °C and 60 min for time reaction. To increase the BCO yield in this study, the natural activated zeolite as a catalyst was employed. BCO was analyzed by Gas chromatography–mass spectrometry (GC–MS) which it can be used to identify carbon number range by percentage of peak areas. It was found that the catalytic pyrolysis has performances better than the thermal pyrolysis. Both of thermal and catalytic pyrolysis were the produce of BCO around 15.2 wt% and 21.4 wt% respectively with the main organic components are gasoline and diesel. Furthermore, paraffin and olefin fraction are major species in the gasoline and diesel. It can be concluded that the content of MSW and their processes has an impact on the fuel produced. In the thermal cracking produce BCO with higher content in the gasoline range. More plastic in MSW is also produce more gasoline while more biomass produces more in diesel range.     

Hydrogen production from wastes

A process for the conversion of municipal solid waste, automobile shredder residue and other plastic/rubber wastes to hydrogen is described both from a technical and an economic point of view. Pilot-plant and modeling results are tools in the analysis. The conversion is carried out in two major process steps. The first or pre-treatment step is based on pyrolysis and results in an intermediate product containing approximately 90% of the primary feed in a suitable physical form for the second step. This second step is Texaco's high-temperature, high-pressure gasifier which is based on partial oxidation and converts the organic components to synthesis gas (CO and H₂). Total thermal conversion efficiency for waste to hydrogen is found to be a strong function of feedstock quality. For typical MSW feedstocks, an efficiency of 40–50% is predicted for an integrated process. Fossil-fuel feedstocks such as waste plastics and scrap tires result in efficiencies of the order 60–70%. The cost of produced hydrogen is approximately $15/GJ for typical MSW with a tipping fee of $50/ton, but drops to $6/ton for high-plastics waste that carry a tipping fee of $100/ton.     

Plasma fixed bed gasification using an Eulerian model

Gasification of solid waste is considered as a green and sustainable solution to perform energy recovery from several waste streams. This work aims to adapt an Euler-Euler multiphase mathematical model to understand the effects of physical and chemical factors, i.e. equivalence ratio (ER), steam to fuel ratio (SFR), and input plasma power of municipal solid waste (MSW) fixed bed gasification. The model is capable of simulating temperature and velocity fields, as well as gas and solid composition variations inside the reactor. A two-step pyrolysis model is used considering the pyrolysis mechanism of cellulose and plastic components. Drying, pyrolysis, homogeneous gas reactions, and heterogeneous combustion/gasification reactions were also included in the model. It was shown that the proposed model could provide accurate predictions against experimental data with a deviation generally lesser than 10%. Conclusion could be drawn that an ER of 0.3 and an SRF of 0.5 seems to be the most favourable conditions in order to obtain a high-quality syngas. Higher plasma power is favourable to obtain a high-quality syngas. However, the high electric power required penalizes the process efficiency and may compromise the economic viability of a plasma gasification project.     

Comparative study of MSW heat treatment processes and electricity generation

This paper discusses the latest analysis in solid waste thermal treatment methods including life cycle assessment (LCA), process systems, economic and energy analysis. The MSW collected by municipalities such as paper, plastics, organic materials, glass, metals, food, leather and rubber can be utilized, via primary treatment methods which are mainly pyrolysis, gasification and combined pyrolysis gasification (P–G) cycles to generate thermal energy or electricity. The importance of solid waste treatment comes from its potential to convert waste into several sources of energy or fuels such as gasoline, syngas or diesel, eliminate waste, and reduce CO₂ emissions. The process systems are explained in terms of process stages, carrier gases, operating pressures and temperatures, end products and reaction residence time. According to MSW management statistics, landfilling and incineration are considered a major activity and is incompatible with the exponential increase of global production of MSW per year. Environmental analysis shows that combined pyrolysis–gasification has lowest environmental impact with acceptable results for pyrolysis and gasification. Economic analysis shows highest capital cost for combined pyrolysis gasification (P–G) followed by pyrolysis and gasification process systems respectively. Operating and maintenance cost shows highest for pyrolysis, while gasification systems show highest revenue per ton.     

SO2 emission characteristics and BP neural networks prediction in MSW/coal co-fired fluidized beds

The SO₂ emission characteristics of typical MSW components and their mixtures have been investigated in a Φ150mm fluidized bed. Some influencing factors of SO₂ emission in MSW fluidized bed incinerator were found out in this study. The SO₂ emission is increasing with the growth of the bed temperature, and it is rising with the increasing oxygen concentration at furnace exit. When the weight percentage of auxiliary coal is being raised, the conversion rate of S to SO₂ is largely going up. The SO₂ emission decreases if the desulfurizing agent (CaCO₃) is added during the incineration process, but the desulfurizing efficiency is weakened with the enhancement of the bed temperature. The fuel moisture content has a slight effect on the SO₂ emission. Based on these experimental results, a 12×6×1 three-layer BP neural networks prediction model of SO₂ emission in MSW/coal co-fired fluidized bed incinerator was built. The prediction results of this model give good agreement with the experimental results, which indicates that the model has relatively high accuracy and good generalization ability. It was found that BP neural network is an effectual method used to predict the SO₂ emission of MSW/coal co-fired fluidized bed incinerator.     

城市固体废弃物典型组分的快速热解产气特性研究

选取城市固体废弃物中的常见六种组分(纸屑、厨余、织物、木屑、塑料、橡胶)作为实验物料进行快速热解实验。在所得实验数据的基础上对热解气体产物的组成以及变化情况进行了分析，并研究了热解混合气的热值随时间变化的情况。通过研究有助于对热解产物进行预测，且能够深入地了解热解机理。     

Effect of particle size on pyrolysis of single-component municipal solid waste in fixed bed reactor

According to the differences in components, three representative components (plastic, kitchen garbage and wood) in municipal solid waste (MSW) were pyrolyzed in a fixed bed reactor to evaluate the influence of particle size on pyrolysis performance of single-component municipal solid waste (MSW). The bed temperature was set at 800°C and each sample was separated into three different size fractions (0–5 mm, 5–10 mm and 10–20 mm). The results show for all the samples particle size has an effect on pyrolysis product yields and composition: smaller particle size results in higher gas yield with less tar and char; the decrease of particle size can increase H₂ and CO contents of gas, as well as the ash and carbon element contents in the char. And the influence is the much more significant for sample with higher fixed carbon and ash contents, such as kitchen garbage, and less for sample with higher volatile content, plastic in the test.