Waste Water Measurement Technology for the Petrochemical Industry

GIMAT (Germany), a manufacturer of a wide range of measuring instruments for continuous water and waste water monitoring, recently presented the new “COD-LAB”. This online analyser is the completely revised version of successful analysers for the online determination of the chemical oxygen demand (COD). Proved by many petrochemical applications the COD-LAB is very reliable and easy to maintain.

The COD-LAB adds hydrogen peroxide (H2O2) to the water sample. The reagent H2O2 forms highly reactive radicals in the UV-reactor which enable rapid oxidation of the sample. The reagent is added in excess and ‘unused’ radicals react to oxygen. The new COD-LAB series of analysers measures the dissolved oxygen (DO) with a luminescence oxygen probe. During analysis the reagent pump is regulated towards a set DO value. The COD-LAB then determines the COD content in the sample according to the reagent pump speed.

With a sufficient calibration interval of one year the DO probe takes long-term stability to extremes, reducing operating costs tremendously. High salt concentrations or sulphur compounds like H2S, common in waste water in the petrochemical industry, are not an issue for the robust COD-LAB. Low consumption of reagent and ease of maintenance are equally impressive. Thanks to a required maintenance time of typically less than half an hour per month, GIMAT’s COD-LAB analyser is top in terms of maintenance.