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介绍了一种不同于现有上装式球阀的新型超低温可在线拆装维修的球阀,为解决在线拆卸的实际需求,提出了一种新的解决方案。当前国内外常见的超低温上装式球阀,使用过程中如果出现泄漏只能是在线更换对应的零件,其更换过程非常繁琐且更换后阀门整体的密封性能无法当场得到验证,只能等到管线再次开车时才能确认。了解可在线拆装维修的球阀优化结构,降低了加工难度,节省了成本。成品不仅在线维修更方便,且更换零配件之后,可以当场检测其维修后的密封性能,为管线的停车检修节省了更多的时间。同时维修时操作的难度更低,可以完美解决了当前上装式球阀难拆难修的问题。 相似文献
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为了明晰真实组分比例下实际造纸固废的热解特性以及组分间协同效应对热解行为的影响,通过人工分拣确定实际造纸固废的真实组分比例,进行了TG-FTIR和Py-GC/MS实验,并结合DG-DAEM动力学分析,系统地研究了组分协同效应对造纸固废热解行为及其主要热解产物分布的影响机制。结果表明,组分协同效应对实际造纸固废热解过程具有显著影响。组分协同效应不仅有利于造纸固废热解过程中挥发分的释放,还可以有效促进CH4小分子的生成。进一步的动力学分析表明,造纸固废混合样品热解过程中降解反应更占优势。此外,在不同温度下,混合样品主要液态热解产物分布中碳氢化合物相对含量的实验值总是高于其理论值,而总的含氧组分的相对含量的实验值总是低于其理论值,混合样品组分间的协同效应有利于热解产物中含氧组分的脱氧以及向烃类产物的转化。 相似文献
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Physicochemical properties of bio-oil obtained from fast pyrolysis of rice husk were studied in the present work.Molecular distillation was used to separate the crude bio-oil into three fractions viz.light fraction,middle fraction and heavy fraction.Their chemical composition was analyzed by gas chromatograph and mass spectrometer(GC-MS).The thermal behavior,including evaporation and decomposition,was investigated using thermogravimetric analyzer coupled with Fourier transform infrared spectrometer(TG-FTIR).The product distribution was significantly affected by contents of cellulose,hemicellulose and lignin.The bio-oil yield was 46.36%(by mass) and the yield of gaseous products was 27%(by mass).The chemicals in the bio-oil included acids,aldehydes,ketones,alcohols,phenols,sugars,etc.The light fraction was mainly composed of acids and compounds with lower boiling point temperature,the middle and heavy fractions were consisted of phenols and levoglucosan.The thermal stability of the bio-oil was determined by the interactions and intersolubility of compounds.It was found that the thermal stability of bio-oil was better than the light fraction,but worse than the middle and heavy fractions. 相似文献
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生物质的多组分热裂解动力学模型 总被引:18,自引:1,他引:17
热重试验结果表明组分不同的生物质的差分失重曲线存在明显差异,用传统的单组分热裂解动力学模型不能解释此现象,结合生物质的组分建立相关的动力学模型来阐述这种差异.花梨木由于其较高的半纤维素质量分数使得纤维素和半纤维素的热失重峰出现明显分离,导致其差分失重曲线在到达失重率最大值前存在一个明显的"肩状峰", 而水曲柳和杉木的半纤维素质量分数相对较低使得差分失重曲线较为光滑.基于生物质的组分独立热分解的假设建立了多组分反应动力学模型,并依据花梨木的试验数据得到了优化后的纤维素、半纤维素和木质素的热裂解动力学参数.利用该模型对杉木和水曲柳的热失重行为进行模拟,得到了与试验结果较为吻合的计算结果. 相似文献