The Hach BioTector 7000i TOC-TN Online Analyser, or Total Nitrogen Analyser is an additional analysis tool available from BioTector Analytical Systems. When the BioTector oxidises organic carbon compounds (for TOC measurement) it also oxidises bound (organic and inorganic) nitrogen compounds and ammonium compounds into nitrate (NO3-). This nitrate is present as an aqueous ion in the oxidised sample fluid in the BioTector reactor.
Total Nitrogen (TN) result:
When TOC analysis is complete, the sample fluid is brought from the reactor into a measuring cell. Here the spectrophotometer analyses the wavelengths applicable to nitrates. The result is displayed as Total Nitrogen (TN). A cleaning fluid is then passed through the measuring cell automatically, which ensures that operator cleaning and maintenance is kept to an absolute minimum.