合成气总硫在线与离线测量结果偏差原因分析

Cause Analysis of Deviation Between Online And Offline Measurement Results of Total Sulfur of Syngas in Purification Unit

煤化工生产工艺中,合成气净化装置两个系列酸性气体脱除单元分别设置一台在线色谱分析仪(AT-1002、AT-2002),配置火焰光度检测器对痕量级别的总硫(H_(2)S和COS)含量进行监测。每台在线色谱分析仪设置A/B/C/D 4个流路,其中A/D流路用于测量酸性气脱除塔塔顶出口痕量总硫含量,仪表测量量程为0ppm~1ppm。工艺操作人员反映净化装置在线分析仪表测量数据不准确,测量结果经常高于控制指标,分析检测中心离线测量结果基本都在控制指标范围之内,在线和离线测量结果存在明显偏差。从取样系统的各个方面详细对比了在线和离线分析的区别,详细论述了影响总硫测量准确性的因素,找到了合成气总硫在线与离线测量结果偏差的原因,为工艺操作人员做出正确的操作判断提供准确可靠的数据依据。

In the coal chemical production process,an online chromatographic analyzer(AT-1002,AT-2002)was set up in two series of acid gas removal units of syngas purification unit to monitor trace levels of total sulfur(H_(2)S and COS)with flame photometric detector.Each online chromatographic analyzer is equipped with four flow channels A/B/C/D,in which A/D flow channel is used to measure trace total sulfur content at the top outlet of the acid gas removal tower,and the instrument measurement range is 0ppm~1ppm.The process operator reported that the measurement data of the online analysis instrument of the purification device was inaccurate,and the measurement results were often higher than the control index.The off-line measurement results of the analysis and testing center were basically within the range of the control index,and there were obvious deviations between the online and off-line measurement results.The difference between online and off-line analysis is compared in detail from all aspects of sampling system,the factors affecting the accuracy of total sulfur measurement are discussed in detail,and the reasons for the deviation between online and off-line measurement results of total sulfur of syngas are found,which provides accurate and reliable data basis for the process operators to make correct operation judgment.