Maximum Interference Rejection
Comet avoids the common error of a differential conductivity measurement to arrive mathematically at the “TOC” value. That alternate method measures the incoming sample conductivity assigning a “TIC” value to it, then exposes the raw sample to UV in a Reactor and measures the “CO2
” of the reacted sample by another conductivity sensor assigning a TC value to that separate measurement. Accuracy of the TIC concentration determination therefore becomes crucial to an accurate mathematical determination of true TOC concentration. This method suffers the following errors:
- Raw source water normally contains not only CO2 from the natural environment and other TIC as carbonates which convert to CO2 in an acidic liquid medium but also contains many other ions that interfere with the desired TIC/CO2 only analysis. Thus to classify the conductivity of the raw sample as “TIC” presents uncorrected error that will be cumulative in the mathematical derivation of “TOC.” This often results in false negatives and false positives and has been rendered unsuitable for controlled low ppb product waters.
- Disregarding the limitation of 1, above, when multiple analyses are required to derive a controlled mathematical result, in this case TOC, cumulative error of the individual measurements add resultant error to TOC analyses.
What does Comet do to provide more accurate TOC results?
Comet conforms to long established EPA approved methods whereby the TIC as carbonates are all converted to dissolved CO2
and eliminated by sparging. TOC is then directly analyzed more accurately without interference from TIC. Only a single analysis for the CO2
generated by oxidizing organic carbon represents the most accurate analysis of TOC directly and without interferences and multiple analyses with questionable TOC results.
Most Sensitive TOC Analytical Method
Comet’s patented method of CO2
concentration provides up to ,900% realized gain in TOC analysis sensitivity.
Comet does not confuse “continuous sampling” with “continuous analysis” and clearly warrants that Comet’s analytical method is continuous throughout, not continuous sampling with a “batch” analysis as others do. Advantages of continuous analysis include no loss of data between otherwise batch analysis and cleanup cycles, which is a clear advantage in process monitoring and control. While analytical batch methods may attribute response time to individual batch analyses, through-put for the total cycle between samples is the important response factor for process control. Comet’s continuous analysis leaves no similar uncertainties over batch analysis.
Comet’s PLC Adds Reliability Over Custom Processors
Critical government and industrial plants are increasingly choosing commercial Programmable Logic Controllers for reliability, ease of service and procurement advantages. Comet has selected a worldwide network that distributes and services a well know manufacturer of its PLCs.