On-line COD analyzers
MICROMAC COD is a microprocessor controlled OnLine analyzer specifically designed for automatic COD Potassium Dichromate method monitoring on several types of watersmatrix.
Two version of COD analyzers are available: dichromate method and permanganate index method.
The dichromate method follows the international standard where in the sample, after filtration,Potassium Dichromate, Mercury (II) sulfate and Sulfuric acid with a proper catalyst are added; Mercury (II) sulfate concentration is adjusted to mask the expected Chloride amount.
The sample is then heated at 170° for 20 minutes or at 150° up to 2 hours (digestion time anddigestion temperature can be adjusted depending on the matrix to digest completely all the substances that give a contribute to COD). After digestion the sample is cooled and the absorbance measured at 592 nm is proportional to a COD concentration.
The permanganate index is defined as the quantity of oxygen, expressed as mg/l, equivalent to the consumed permanganate when a water sample is treated with as solution of potassium permanganate in acid environment and at a temperature of 100°C for 10 minutes.
The sample is mixed with diluted sulphuric acid, it is then heated at about 100°C, when the first addition of KMnO4 is performed: this first addition may be followed by others, depending on the measuring range. The digestion time in the standard configuration is set to 10 minutes but it can be selected depending on the matrix. After digestion the sample is cooled and the decrease of the absorbance measured at 525 nm corresponds to the permanganate consumed by the organic substance.
ROBUST AND RELIABLE
Designed for industrial and Environmental On Line applications ensures the highest level of robustness in the electronics, mechanics and hydraulics components. Complete separation between electronics and hydraulics plus a simple and robust LFA* hydraulics allows easy maintenance and long terms reliable operations.
EASY TO INSTALL
The analyzer is delivered after a long and successful series of factory tests ready for installation and setup; . it is provided with complete set of spares for start up. To start monitoring is enough to connect reagents, sample line, waste line and power supply.
When the Calibration Time interval expires the analyzer perform a Calibration Cycle, storing and checking the new calibrant O. D. If new O.D. exceed selected limits, an alarm contacts is closed.
User selectable; between two measurements the analyzer remain in stand by mode, without reagents consumption.
FEATURES AND BENEFITS
- Fully automatic operation.
- Long autonomy; low maintenance, low operating cost.
- Low reagents consumption; short preparation time; low disposable costs.
- Easy operation; plug in analyzer, no special training is required.
- Electronics and hydraulics completely separated.
- Serial interface for local o remote PC connection (optional).