S250 O.U.R. (Oxygen Uptake Rate) Test Portable meter to measure the biomass respiratory activity Oxygenation and stirring assembly with incorporated lead batteries 500 ml ask with airtight stopper and magnetic stir bar Polarographic probe with two temperaturecompensated electrodes Laptop with RS232 serial port and printer port, graphic LCD 4Selectable measuring ranges: 0.00/5.00/10.0/20.0 ppm of O2; 4Selectable measuring times: 2, 5, 10, 15, 20, 30, 60 min. 4Fully-portable system housed in shock-resistant aluminium case (460x330x150 bxhxd - 5 kg). Complete with: – Polarographic O2 measuring probe with two temperature-compensated electrodes (S423) – Interface card + cable for connection to PC (via RS 232 port) – 500 ml ask with airtight stopper – Stirring/oxygenation unit powered by rechargeable batteries or 220 V mains power – Display and measurement management software (for PCs running Windows 98 or higher). The program supplied is used on PCs, laptops or desktops, with an RS 232 serial port. Complete system for taking respirometric measurements with parameter setting via dedicated software. Displays measurements in graphical and tabular form (O2 consumption/ time) with the nal result expressed directly as a ratio in mg of oxygen consumed per mass of activated sludge and brought to the analytical standard of 20 °C. Precision ± 1% of the f.s. at constant temperature. Storage of measurements and relative graphics with option to print.

Measuring the OUR To control the efciency of a biological activated sludge treatment plant, the test for determining the Oxygen Uptake Rate is performed on a sample taken directly from the oxidation/nitrication basin. The classic method involves recording the consumption of oxygen dissolved a sample of activated sludge, with known MLSS concentration and volume, previously brought to rapid saturation with a forced ventilation system and kept constantly mixing, at regular intervals. Probe thermo-compensated The time/concentration of oxygen pairs are then turned into a graph, and a descending, almost...