The Application in Water Determination of WE-TN-GC2007 Total Nitrogen On-Site or On-Line Automatic Monitoring Instrument

Nitrogen compounds were the main contaminants in natural water, and the measurement and on-site automatic monitoring of total nitrogen in lakes and rivers which might be polluted by nitrogen were the important tasks for environmental engineers. A new and rapid instrumental technique has been developed to measure organic and inorganic nitrogen compounds in both ground water and contaminated source water. Conceived as a replacement for normal procedures which were measured in two different wavelengths (220 and 275 nm) by digesting with potassium persulfate spectrophotometric method, this on-site or on-line monitoring instrumental system measures total nitrogen by digestion with UV-alkaline potassium persulfate and reduction with hydrazine sulphate spectrophotometric method in the single wavelength of 546 nm and yields relative standard deviation (RSD) of reproducibility 0.7%, zero drift 2.7%, range drift 2.2%, linearity error 0.87%, mean time between failures (MTBF) more than 1440 hours. When applied in water samples determination, the average absolute values of relative error (A) of different water samples were less than plusmn10% and had a well reproducibility.