激光前向散射法颗粒物在线监测仪在污染源超低排放烟气测定中的适用性研究

Applicability Research of Laser Forward Scattering Particulate Matter Online Monitor in Ultra-low Emission Monitoring of Pollution Sources

对激光前向散射法颗粒物在线监测仪在污染源超低排放烟气测定中的准确度和精密性进行讨论,以低浓度颗粒物手工重量法作为参比方法,建立两者测定颗粒物浓度的线性拟合关系。通过分析线性拟合曲线的斜率和截距数值的绝对误差来考察不同型号在线监测仪的准确度;选取1 a时间跨度内4个时段的颗粒物浓度的K系数变化趋势来分析在线监测仪的精密性。结果表明:稀释加热低量程和稀释加热中量程设备在颗粒物质量浓度0~5 mg/m^3区间测定结果更具优势;利用线性拟合斜率、截距数值的绝对误差考核法在日常低浓度颗粒物比对考核中更有代表性;选用带全程加热功能的在线设备及加大设备维护频次更有利于降低高湿度烟气对测量结果的干扰。

The accuracy and precision of online monitoring instrument for particulate matter in ultra-low emission flue gas from pollution sources by laser forward scattering method were discussed.Using manual gravimetric method of low concentration particulate matter as the reference method,the linear fitting relationship between them was established.By analyzing the slope and intercept of linear fitting curve,the accuracy of different models of on-line monitor were discussed.The variation trend of K coefficient of particulate concentration in four time periods in a one-year span was selected to analyze the precision of online monitor.Results showed that:the dilution heating monitor of low range and medium range were more advantageous in measuring particulate matter in the concentration range of 0~5 mg/m^3;The assessment methods of linear fitting curve are more representative in the daily comparison of low-concentration particulate matter;The online monitor with heating along the whole tubes and increased equipment maintenance frequency are more efficent in reducing the interference to the measurement results of high humidity.