【作者】 李晋；

【导师】 陈爱侠；

【作者基本信息】 长安大学 ， 工程硕士 环境工程（专业学位）， 2018， 硕士

【摘要】 能源与环境问题,逐渐成为制约人类社会进步和发展的关键问题,开发清洁、高效的新能源己成为世界各国的研究热点。污泥作为一种生物质资源,其中含有大量有机质可回收利用,如可通过生物发酵、热解气化等技术制取热值高、清洁无污染的氢能。其中,污泥热解制氢具有可操作性行强、反应时间短、处置彻底等优点。本文采用机械化处理与固定床热解技术结合方式对污泥进行热解研究。通过分析不同催化剂,不同温度和不同含水率条件下污泥热解产物分布特征,并采用傅里叶漫反射红外光谱仪、比表面积仪、综合热分析仪和X射线衍射仪进行污泥及其热解焦炭固体表征分析,探究污泥热解产气、焦炭和焦油的机理,得出以下主要结论:（1）选择添加催化剂CaO混合料,可明显提升热解产气品质,使得热解气质量分数、污泥热解气体产率、单位质量污泥产气低位热值和H₂产率达本文最大值,分别为;32.1%、0.441m³·kg^-1、68.644kJ·kg^-1和7.377mol·kg^-1;添加不同催化剂混合料热解焦炭FTIR图谱中特征吸收峰数量较少且强度较低,有机物已得到较为充分的分解;污泥中加入催化剂CaO和CaO-焦炭,使得热重第三阶段失重率增加,前者提高了有机物分子动能和表观活化能(13.39-70.43kJ·moL^-1),进而促进热解反应进行。（2）随着温度的升高,混合料热解产气品质得到提升,热解焦炭质量分数呈下降趋势,热解焦油质量分数在800℃时有明显提升,其余温度下其质量分数基于40%上下波动;热解反应中生成大量方解石,抑制混合料热解焦炭吸附量及孔结构发达程度。（3）适当的含水率有利于提高产气结果,当混合料含水率为45%时,其热解后游离和缔和羟基发生脱羟基作用生成H₂O,提升热解产气品质,尤其可提升热解气体中H₂质量分数,并使其达本文最大值45.1%;不同含水率下混合料球磨和热解后矿物中都未检测到玻璃体鼓包,混合料整体结晶度较好。更多还原

【Abstract】 Energy and environmental issues had gradually become the key issues that restricted the progress and development of human society.The development of clean and efficient new energy had become a research hotspot in countries around the world.As a biomass resource,sludge contained a large amount of organic matter that could be recycled and used.For example,bio-fermentation,pyrolysis and gasification could be used to produce high-value,clean and pollution-free hydrogen energy.Among them sludge was carried out by pyrolysis for hydrogen-rich gas production had the advantages of strong operability,short reaction time and thorough disposal.In this paper,the pyrolysis of sludge was studied using a combination of mechanochemical pretreatment and fixed bed pyrolysis.By analyzing the distribution characteristics of the sludge pyrolysis products under different catalysts,different temperatures and different moisture contents,and the FT-IR spectrometer,specific surface area analyzer,integrated thermal analyzer,and X-ray diffractometer were used to characterize the solidification of sludge and pyrolysis coke,exploring the mechanism of sludge pyrolysis gas,coke and tar.The following main conclusions were drawn:（1）The choice of adding catalyst CaO mixture could obviously improve the quality of pyrolysis gas,and make the maximum value of the pyrolysis gas mass,the pyrolysis gas yield of the sludge,the low calorific value of the unit mass sludge and the yield of H₂,respectively,32.1%,0.441m³·kg^-1,68.644kJ·kg^-11 and 7.377mol·Kg^-1,respectively.The number of characteristic absorption peaks in the FTIR spectra of pyrolysis coke added to different catalyst mixtures was small and the intensity was low,and the organics had been fully decomposed;The addition of catalysts CaO and CaO-coke to the sludge increased the rate of weight loss in the third stage of the thermal weight,and the former enhanced the kinetic energy and apparent activation energy of organic molecules（13.39-70.43 kJ·moL-1）,thereby promoting the pyrolysis reaction.（2）With the increase of temperature,the pyrolysis gas production quality of the mixture was improved,the pyrolysis coke mass fraction showed a downward trend,and the pyrolysis tar mass fraction increased significantly at 800°C,while at other temperatures,the mass fraction was based on 40%fluctuations;A large amount of calcite was generated in the pyrolysis reaction,and inhibiting the pyrolysis coke adsorption and pore structure development of the mixture.（3）Appropriate moisture contents was beneficial to improve gas production results.When the moisture contents of the mixture was 45%,the pyrolysis of free and dehydroxylation of the associative and hydroxyl groups produced H₂O to increase the quality of the pyrolysis gas,especially the pyrolysis gases.H₂ mass fraction reached the maximum value of 45.1%.The vitreous bulge was not detected in the ball milled and pyrolyzed minerals under different moisture contents,and the overall crystallinity of the mixture was good.更多还原