The ammonia nitrogen levels detected online in wastewater are more than twice as high as those obtained through manual analysis; why is the manual analysis giving higher values?
Thread Content
The ammonia nitrogen levels detected online in wastewater are more than twice as high as those obtained through manual analysis; why is the manual analysis giving higher values?
Online ammonia nitrogen analyzers generally have strict filtration measures, and some ammonia nitrogen components may be lost during this filtering process. During the alkalization of the sample to remove ammonia nitrogen, the efficiency is not very high, which results in further loss of ammonia nitrogen. Additionally, when laboratories analyze ammonia nitrogen, they may homogenize the sample, which can lead to some destruction of microbial cells and the release of the ammonia nitrogen contained within them. The result will then be as you said.
I think there are two points: First, online monitoring instruments are precise, allowing for accurate analysis； Second, different analysis methods for the two will also lead to different results
From your judgment, it can be seen that you are not familiar with online analysis and ammonia nitrogen detection methods. The precision of online analyzers is not much different from that of laboratory analyzers; in terms of the accuracy of sample analysis, laboratory analyzers may be more precise, but online analyzers offer better real-time performance. In environmental monitoring, the analysis methods for ammonia nitrogen must comply with **standards or environmental regulations. Even when different analysis methods are used, the presence of standard samples as a reference for calibration ensures that there are no significant discrepancies in the results for the same sample. The source of the deviation in the original poster’s data is not the analysis method, but rather the different processing procedures applied to the samples.