Online Monitoring of Nitrogen Elimination in Vienna’s Main Sewage Treatment Plant

Vienna’s Main Sewage Treatment Plant was expanded in the years of 2004 and 2005, now designed for a population equivalent of 4.0 million and able to clean 680,000 m3 of wastewater per day. In the tender, the operator of the plant had specified online spectrometry to be the method for monitoring of COD, Nitrate and TSS. s::can Messtechnik GmbH, Vienna, obtained the order for on-line instrumentation as a sub-supplier for Siemens AG Austria. In the beginning of 2005, 27 spectrometric probes of different types were purchased, most of them immediately installed and set into operation. The results of a test run for “verification of uniformity & accuracy” during a tough commissioning procedure proved high reliability, low operational costs and best precision of the installed s::can measuring instruments.