Metrohm's LAR QuickTOC solution can be used by airports to measure the total organic compounds (TOCs) of their glycol run-off.
The goal is the precise/reliable measurement of TOC to determine whether the run-off can be discharged directly into an irrigation reservoir or if it has to be diverted to a storage basin for dilution or treatment.
Glycol is poisonous to animals and the environment and high concentrations will cause the bacteria in a wastewater plant to go dormant or die.
Discharging high concentrations of glycol will cause serious problems at the wastewater plant and possible fines.
The challenge is to catch the entire run-off and make the proper determination.
The TOC must react quickly and be repeatable.
Glycol is a sticky viscous substance and it is easy to contaminate samples, causing false readings and slow response.
False readings and slow response can cause the airport to waste money by missing an event, resulting in fines.
Diverting low concentrations to treatment is not cost effective.
Therefore, the system must purge and rinse the old sample before taking the new sample to prevent these problems.
Metrohm claims that the solution is to install the LAR QuickTOC at the inlet of the plant for several reasons.
The sample is taken using the LAR flow sampler that delivers the fresh sample to the QuickTOC without pre-filtration.
A magnetic stirrer under the sample vial keeps the sample in suspension.
The X-Y dispensing system transfers the sample from the sample vessel into the combustion reactor, minimising the amount of tubing and ensuring fresh sample with minimal cross contamination.
The injection needle of the dispenser system has an inside diameter of 0.8mm, which prevents clogging, and after each sample the injection needle is immediately rinsed with distilled water in reverse-flow direction.
This also prevents cross contamination, which can result in a slow response or false readings.