沼渣热解中硫释放与迁移研究  

Sulfur Release and Migration in Digestate Pyrolysis

作　　者：郭玉乾 张健[1] 张瑞娜 付乾 张正龙 张子龙 GUO Yuqian;ZHANG Jian;ZHANG Ruina;FU Qian;ZHANG Zhenglong;ZHANG Zilong(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;Shanghai Institute for Design&Research on Environmental Engineering Co.,Ltd.,Shanghai 200232,China;Shanghai Tianma Renewable Energy Co.,Ltd.,Shanghai 201600,China)

机构地区：[1]上海理工大学环境与建筑学院,上海200093 [2]上海市环境工程设计科学研究院有限公司,上海200232 [3]上海天马再生能源有限公司,上海201600

出　　处：《生物质化学工程》2025年第2期30-38,共9页Biomass Chemical Engineering

基　　金：上海市科委标准项目(22DZ2200200);上海市科委技术带头人项目(23XD1433500)。

摘　　要：城市餐厨垃圾经过厌氧发酵,可生成生物燃气和转化为固相沼渣,对沼渣进行热解处理可进一步利用其有机化学能。本研究对沼渣热解过程中硫释放的机理过程进行探讨,利用可控温沉降炉实现不同热解温度下沼渣、水稻秸秆、玉米秸秆的热解过程,利用全硫形态测试及X射线光电子能谱(XPS)分析仪分析了焦炭中硫与灰的相互作用,并用热重-质谱联用(TG-MS)仪跟踪了有机硫与无机硫的气相释放。研究结果表明:沼渣含硫量较高,约0.56%,硫主要来自于厌氧消化工艺;秸秆含硫量约0.2%。当热解温度为400℃与600℃时,沼渣分别有62%与85%的硫释放;低温时2种秸秆中的硫部分会以硫酸盐形式存在于灰中。硫的释放过程中,沼渣中的大部分的硫(约占95%)离开样品颗粒表面,进入热解气,而2种秸秆中的硫不易在热解过程中释放,封存于焦炭中,但沼渣和秸秆的硫释放形式均以H_(2)S为主。在热解过程,焦炭中硫迁移有3个过程:沼渣焦炭中硫酸盐生成发生在200~400℃,秸秆中硫酸盐生成在400~600℃;在600~1000℃时,硫酸盐发生热分解;高温(1000℃)时,焦炭中硫形式主要以大分子有机硫(砜、亚砜、噻吩)形式存在。Urban kitchen waste underwent anaerobic fermentation,a part of them decomposed into usable biogas and another part of them converted into solid digestate.The pyrolysis of digestate could further utilize its organic chemical energy.In this study,the mechanistic process of sulfur release during the pyrolysis of digestate was investigated.The pyrolysis process of digestate and straw at different pyrolysis temperatures was realized in a controllable temperature settling furnace.The interaction between sulfur and ash in the coke was analyzed using the total sulfur morphology test and X-ray photoelectron spectroscopy analyzer.The gas-phase release of organic and inorganic sulfur was tracked by thermogravimetric-mass spectrometry.The results showed that the sulfur content in digestate was relatively high,accounting for 0.56%,mainly deriving from the anaerobic digestion process.The sulfur content in straw was approximately 0.2%.When the pyrolysis temperatures were 400℃and 600℃,62%and 85%of sulfur were released from digestate,respectively.At low temperatures,part of the sulfur in straw existed as sulfate in ash.During the sulfur release process,most of the S(about 95%)in digestate left the surface of the sample particles and entered the pyrolysis gas.However,the S in the biomass straw was not easy to be released during the pyrolysis process and was stored in the coke.Nevertheless,the sulfur release form of digestate and biomass straw was H_(2)S.In the pyrolysis process,there are three processes for sulfur migration in coke:sulfate generation in digestate occured at 200-400℃;sulfate generation in biomass straw occured at 400-600℃;sulfate thermal decomposition occured at 600-1000℃.At high temperature(1000℃),sulfur in coke mainly existed in the form of macromolecule organic sulfur(sulfone,sulfoxide,thiophene).

关 键 词：厌氧沼渣 秸秆 热解 硫释放 X射线光电子能谱分析 

分 类 号：TQ35[化学工程]