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DOC - What is Dissolved Organic Carbon?

Definition

Dissolved Organic Carbon (DOC) is a measure of the organic carbon, dissolved in a water body and does not include the suspended solids component. The sample is filtered using membrane technology to remove particulate greater than 0.45 micron. The sample can be continuously analysed by the Protoc analyser to provide real-time COD or BOD prediction.

Methodology

A filtered sample is pumped into a sparge vessel with acid and agitated with gas, to remove the inorganic carbon typically present as carbonates. The prepared sample is then delivered to a reaction vessel, containing a high intensity UV light source and oxidising reagent. The organic carbon is oxidised to form CO2, which is liberated by a carrier gas and delivered to an infrared detection system. The controller compares the output from the detector against automatic calibration data, to report the measured Organic Carbon (DOC) concentration.

Protoc 300 TOC Analyser

Protoc 300 TOC Analyser

PPM Membrane Panel Filter

PPM Membrane Panel Filter

Important Features Of Test

The recognised Total Organic Carbon method can be used on-line for continuous measurement providing real time data with a response time from under 3 minutes. The Protoc DOC measurement is repeatable and when used with the correct sample preparation and delivery system, is very reliable even in demanding waste-water applications. It is therefore suitable for monitoring and control applications and often be used to predict oxygen demands.