• Liz @ QROS

Accurate Analysis of Oily Waste in Minutes - it's easy

Some of the UK's largest Waste Management companies are now using the QED and saving thousands. The QED is the only single analyser, either in the laboratory or on site, that can accurately identify the hydrocarbon- so easy to use, you can do it yourself for results in minutes from as little as £5 per sample.

Allowed by the Environment Agency.

The accuracy of any analysis is highly dependent upon the calibration. You must calibrate the analyser with the same hydrocarbon type that is in the sample to get the most accurate results. If you cannot identify the hydrocarbon type in the sample and you use a calibrator that is different, the results obtained will be inaccurate. This is true for both laboratory based analysis as well as on site analysis. High quality laboratory analysis will make efforts to identify the compounds in the sample before setting up the calibration, but typical low cost (but MCERTS accredited) do not do this. The QED is the only hydrocarbon analyser that can positively identify the hydrocarbon type and therefore apply the correct calibration to give accurate results.

Turbidometric, immunoassay, infra red and colourimetric methods supply just one hydrocarbon type for calibration and a simple conversion chart to estimate hydrocarbon concentrations if the compounds in the sample are expected to be something else. 1st generation UVF analysers such as Sitelab only include BTEX, PAH and Diesel calibrators, costing over £200 for each set. Sitelab requires 3 separate sets of calibrations and analysis to be carried out to obtain the BTEX, PAH and Diesel results.  This is very time consuming, especially when single samples require analysis. For all of these techniques, when the sample does not contain hydrocarbons that match the calibrator compounds, the results will be inaccurate. On most sites, the actual hydrocarbon present in the samples can be very different from the diesel calibrator supplied. Degradation significantly changes the hydrocarbon chemistry and coal tars, creosotes and oils are completely different from diesel. For this reason, these 1st generation analysers and test kits are only suitable for very basic screening, just capable of differentiating between clean and grossly contaminated soil.

The QED takes less than 30 seconds to generate a full set of calibration curves for BTEX, JP5, JP8, kerosene, diesel, degraded fuel, bitumen, creosote, coal tar, road tar, motor oil, hydraulic oil, transformer oil and PAH, including BaP. The QED system is factory calibrated and uses a single surrogate calibrator in the field to generate calibration curves for all of the above compounds. This means much lower running costs and a faster simpler process which minimises the inevitable errors associated with running multiple concentration calibrations in the field. Custom calibrations can also be created easily.

With an actual analysis time of a few seconds, the QED identifies the hydrocarbon type and applies the closest matching calibrator. The QED achieves greater accuracy by being able to split the sample signal into as many as 3 separate hydrocarbon types, applying the calibration curve that most closely matches each of the hydrocarbon types. For example, degraded diesel could be considered to be a mixture of undegraded diesel and degraded fuel. The QED identifies the proportions of diesel and degraded fuel and applies the corresponding calibrations to each proportion. No other analyser or test kit can do this.

Extraction of soil samples takes approximately the same time for all methods, which is about 5 minutes. Water samples take about 1 minute. The actual analysis time using the QED is just a few seconds. Older generation analysers and current test kits take much longer. All QED results are saved as an Excel file, which can be printed as a hard copy including the sample fingerprint. Colourimetric, immunoassay and turbidometric require results to be manually recorded, as do 1st generation UVF and Infra Red analysers. The QED is the only analyser to provide an easily identifiable fingerprint with the results.

Infra red and colourimetric kits use solvents which are either very expensive or hazardous, so disposal costs are very high. The QED uses methanol, a low cost and environmentally benign solvent, which we provide in a low cost format.

Quality control in the QED is very comprehensive, automatically monitoring for correct analyser operation, baseline drift and calibration drift. Potential errors in the analysis due to turbidity, particulate, sample over or under the calibration range are monitored. For older generation UVF and Infra Red analysers an important error is caused when the sample is too concentrated, causing the analyser to give a false and significantly lower concentration value, where the user would be unaware that this problem had occurred. The QED is the only analyser to be able to identify this situation and alert the user. A dilution factor is even suggested to ensure a rapid re-run.

The QED can indicate if there are background organics in the sample and then subtract these compounds from the result to give a more accurate result. Ist generation UVF, infra red, colourimetric, turbidometric and gas chromatography methods often include these background organics in the results significantly over reporting the actual TPH value.

It takes less than 5 minutes from getting a soil sample for the QED to give accurate results in a single test for BTEX, TPH, PAH and BaP as well as identifying the hydrocarbon as petrol, JP5, JP8, kerosene, diesel, degraded fuel, bitumen, creosote, coal tar, road tar, motor oil, waste oil, hydraulic oil or transformer oil. Water samples can be analysed in seconds.

The QED is designed and built in the UK by QROS. QROS can also supply the latest generation of on site analysers for metals and other contaminants.

The QED and other analysers are available for hire from QROS.

Contact QROS now for prices, and the latest information about on site methods.

QROS Ltd: 0800 046 9695



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