On-line COD Determination - corrosive environment or explosion-proof - (ATEX Zone 1 and 2)

LAR Process Analysers AG introduces the QuickCOD^®_o - a new on-line COD measuring system with a closed circuit cooling system to avoid the permeation of ambient air during the operation as well as optionally in stainless steel (IP65) or specially coated housing.

To avoid any infiltration of aggressive air when working in particularly aggressive environments the analyser can be “pervaded” with a small quantity of instrument air additionally. Furthermore, the analyser may also be equipped for explosive environments being certified for ATEX Zone 1 and 2.

The measurement principle is based on the real oxygen consumption caused by the oxidation of the organic components when using the 'LAR high temperature method'.

Thus, the determination of the COD is possible even under extremely difficult conditions and within just a few seconds avoiding the usual efforts when comparing the laboratory values as required.

This method requires neither reagents nor substances dangerous for the environment or for the operator. Moreover, the high temperature combustion at 1200°C guarantees the complete oxidation of the sample's organic components. Only every now and then (in practice monthly) the analyser has to be checked with a standard reducing the maintenance and operational costs in comparison to other COD devices.

This measurement system is suitable for every COD application in industrial and municipal waste water treatment. Detection of organic spills and product losses (e.g. in the chemical, petrochemical and food processing plants) or the control of influents and effluents in sewage plants are typical on-line applications.

Even in the case of very high salt concentrations (≥ 20g/l) these COD measurements can be performed without neither errors due to chloride nor interferences due to the matrix influence of the sample. In addition, it is not necessary to dilute the sample. Even fast transformations of the sample's composition do not affect the measurement result. Since the QuickCOD^®_o does not have any memory it proves to be the ideal solution even in cases of extremely varying concentrations (within minutes).

Thanks to the possibility of easily analysing single samples also, the QuickCOD^®_o is suitable for on-line analysis as well as for laboratory tests. Thereby, no harmful reagents - neither to the environment nor for the operator- are needed. Thus, the high temperature method of the analyser contributes to a higher security level during the measuring processes and decreases the laboratory's expenses in time and money.

In conjunction with the patented sample preparation system 'FlowSampler' the QuickCOD^®_o is operating completely filtration-free. If required, the analyser may detect solid waste water components as well, since the sample may be homogenised and the COD may be determined in short time.

Additionally, the QuickCOD^®_o analyser may be combined with a simultaneous TOC measurement. Then, both parameters - COD and TOC - may be determined at the same time, using only one sample, and within just 3 minutes (T₁₀₀ time).