SO_(2)、CS_(2)和H_(2)S作为绝缘气体SF_(6)的重要分解气体,它们的种类和含量对SF_(6)气体绝缘设备的诊断具有重要意义。文中提出了一种紫外吸收光谱法和最小二乘拟合联用的方法用于SF_(6)分解气体的3组分混合气体定量检测。在实验过程...SO_(2)、CS_(2)和H_(2)S作为绝缘气体SF_(6)的重要分解气体,它们的种类和含量对SF_(6)气体绝缘设备的诊断具有重要意义。文中提出了一种紫外吸收光谱法和最小二乘拟合联用的方法用于SF_(6)分解气体的3组分混合气体定量检测。在实验过程中,发现较高体积分数的SO_(2)和CS_(2)对较低体积分数H_(2)S的体积分数计算存在干扰并且干扰的程度大小与两种气体的体积分数呈正相关。因此,文中获得了干扰气体体积分数较高时H_(2)S体积分数计算的修正公式,可以实现3种气体的准确定量检测,SO_(2)和H_(2)S检测范围为1~10μL/L(part permillion),CS_(2)为30~300μg/m L(part per billion)。文中提供了一种简便高效的检测方法,方便集成于检测设备中,为SF_(6)绝缘设备在线监测提供了技术支撑。展开更多
H_(2)S is one of the most important characteristic decomposition components of SF_(6)insulated gas,and the detection of trace H_(2)S is significant for early fault diagnosis of gas insulated electrical equipment.A 157...H_(2)S is one of the most important characteristic decomposition components of SF_(6)insulated gas,and the detection of trace H_(2)S is significant for early fault diagnosis of gas insulated electrical equipment.A 1578 nm wavelength distributed feedback diode laser(DFB-DL)based cavity ring-down spectroscopy(CRDS)experimental platform is developed to monitor the concentrations of H_(2)S in SF_(6)and SF_(6)/N_(2)mixture carrier gas.The detection sensitivity is higher than 1×10^(-6).The absorption cross section parameterσis vital for calculating the concentration.With repeated experiments using standard gas samples,parameterσof H_(2)S in pure SF_(6)and SF_(6)/N_(2)mixture carrier with different mixing ratios is calibrated.Compared with the simulatedσvalues,the influence of carrier gas on the broadening of spectral profile is discussed.The variation of absorption cross sectionσwith different carrier gas mixing ratios is studied as well,so that the calculation of the concentration in the carrier gas of any mixing ratio is possible.Thus,the application of CRDS in trace component detection of gas insulated electrical equipment is promising.展开更多
Upgrading biogas into biomethane not only improves the biogas utilization as vehicle fuel or natural gas substitute,but also reduces the greenhouse gases emissions.Considering the principle of engineering green energy...Upgrading biogas into biomethane not only improves the biogas utilization as vehicle fuel or natural gas substitute,but also reduces the greenhouse gases emissions.Considering the principle of engineering green energy process,the renewable aqueous ammonia(RAA)solution obtained from biogas slurry was used to remove H_(2)S and CO_(2) simultaneously in the hollow fiber membrane contactor.RAA was mimicked in this study using the ammonia aqueous solution mixed with some typical impurities including ethanol,acetic acid,propionic acid,butyric acid and NH4HCO_(3).Compared with the typical physical absorption(i.e.,pure water)removing 48%of H_(2)S from biogas,RAA with 0.1 mol·L^(−1) NH_(3) could remove 97%of H_(2)S.Increasing the NH3 concentration from 0.1 to 0.5 mol·L^(−1) could elevate the CO_(2) absorption flux from 0.97 to 1.72 mol·m^(−2)·h^(−1) by 77.3%.Among the impurities contained in RAA,ethanol has a less impact on CO_(2) absorption,while other impurities like CO_(2) and acetic acid have significant negative impacts on CO_(2) absorption.Fortunately,the impurities have a less influence on H_(2)S removal efficiency,with more than 98%of H_(2)S could be removed by RAA.Also,the influences of operating parameters on acid gases removal were investigated to provide some engineering suggestions.展开更多
文摘SO_(2)、CS_(2)和H_(2)S作为绝缘气体SF_(6)的重要分解气体,它们的种类和含量对SF_(6)气体绝缘设备的诊断具有重要意义。文中提出了一种紫外吸收光谱法和最小二乘拟合联用的方法用于SF_(6)分解气体的3组分混合气体定量检测。在实验过程中,发现较高体积分数的SO_(2)和CS_(2)对较低体积分数H_(2)S的体积分数计算存在干扰并且干扰的程度大小与两种气体的体积分数呈正相关。因此,文中获得了干扰气体体积分数较高时H_(2)S体积分数计算的修正公式,可以实现3种气体的准确定量检测,SO_(2)和H_(2)S检测范围为1~10μL/L(part permillion),CS_(2)为30~300μg/m L(part per billion)。文中提供了一种简便高效的检测方法,方便集成于检测设备中,为SF_(6)绝缘设备在线监测提供了技术支撑。
基金supported in part by the National Key R&D Program of China(No.2021YFF0603100)in part by the Leading Innovation and Entrepreneurship Team in Zhejiang Province(No.2019R01014)
文摘H_(2)S is one of the most important characteristic decomposition components of SF_(6)insulated gas,and the detection of trace H_(2)S is significant for early fault diagnosis of gas insulated electrical equipment.A 1578 nm wavelength distributed feedback diode laser(DFB-DL)based cavity ring-down spectroscopy(CRDS)experimental platform is developed to monitor the concentrations of H_(2)S in SF_(6)and SF_(6)/N_(2)mixture carrier gas.The detection sensitivity is higher than 1×10^(-6).The absorption cross section parameterσis vital for calculating the concentration.With repeated experiments using standard gas samples,parameterσof H_(2)S in pure SF_(6)and SF_(6)/N_(2)mixture carrier with different mixing ratios is calibrated.Compared with the simulatedσvalues,the influence of carrier gas on the broadening of spectral profile is discussed.The variation of absorption cross sectionσwith different carrier gas mixing ratios is studied as well,so that the calculation of the concentration in the carrier gas of any mixing ratio is possible.Thus,the application of CRDS in trace component detection of gas insulated electrical equipment is promising.
基金supports from the Natural Science Foundation of Hubei Province of China(2020CFA107,2020CFB209)the National Natural Science Foundation of China(32002222,52076101)the Fundamental Research Funds for the Central Universities(2662021JC004).
文摘Upgrading biogas into biomethane not only improves the biogas utilization as vehicle fuel or natural gas substitute,but also reduces the greenhouse gases emissions.Considering the principle of engineering green energy process,the renewable aqueous ammonia(RAA)solution obtained from biogas slurry was used to remove H_(2)S and CO_(2) simultaneously in the hollow fiber membrane contactor.RAA was mimicked in this study using the ammonia aqueous solution mixed with some typical impurities including ethanol,acetic acid,propionic acid,butyric acid and NH4HCO_(3).Compared with the typical physical absorption(i.e.,pure water)removing 48%of H_(2)S from biogas,RAA with 0.1 mol·L^(−1) NH_(3) could remove 97%of H_(2)S.Increasing the NH3 concentration from 0.1 to 0.5 mol·L^(−1) could elevate the CO_(2) absorption flux from 0.97 to 1.72 mol·m^(−2)·h^(−1) by 77.3%.Among the impurities contained in RAA,ethanol has a less impact on CO_(2) absorption,while other impurities like CO_(2) and acetic acid have significant negative impacts on CO_(2) absorption.Fortunately,the impurities have a less influence on H_(2)S removal efficiency,with more than 98%of H_(2)S could be removed by RAA.Also,the influences of operating parameters on acid gases removal were investigated to provide some engineering suggestions.
