垃圾渗滤液中总氮检测的适用方法探讨

采用紫外分光光度法及离子色谱法检测垃圾渗滤液中的总氮,针对不同的检测结果,分析两种方法的准确性,并对导致方法不准确的原因进行探讨。结果表明,离子色谱法所测值高于氨氮值的6.7%,其标准曲线在0.05~10.00 mg/L呈现良好的线性,方法检出限为0.018 mg/L,相对标准偏差介于0.84%~4.05%,加标回收率介于95.1%~98.4%,精密度和准确度满足要求,适用于垃圾渗滤液中总氮的测定;紫外分光光度法的标准曲线和精密度虽满足检测要求,但总氮的测定值低于氨氮值的16.0%;导致检测结果偏低的主要原因是消解过程中产生的细微悬浮颗粒对紫外光有散射作用,可通过超滤膜的过滤减弱这一影响。

Explore applicable methods to detect TN in the landfill leachate

Using UV spectrophotometry and ion chromatography to detect total nitrogen （TN） in landfill leachate, analysis the two methods＇ accuracy and investigate reasons from the different test results. The results show that when using the ion chromatography,the values of total nitrogen are higher than 6.7% of ammonia nitrogen,standard curve presents excellent linearity in 0.05 - 10.00 mg/L,detection limits is 0.018 mg/L and RSD is between 0.84% - 4.05%, recoveries is between 95.1% - 98.4%, precision and accuracy are also meet the requirements. So the IC method is applicable to the determination of total nitrogen in landfill leachate;The standard curve and precision can satisfy the testing requirements, but the measured results of total nitrogen is lower than 16.0% of ammonia nitrogen when using UV spectrophotometry. The main reason is that the tiny suspended particles produced during the digestion scattered the UV, the filtration by ultrafiltration membrane can reduce this effect.