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PCP-project Mercury Free COD

This pre-commercial procurement (PCP) can hopefully set an example of how a procurement can be an efficient tool for developing innovative solutions, matching and introducing them to the market. Here you will find the progressions made in this Project.

The execution of this project followed the guide for PCP's that Vinnova developed in 2013 based on the guidelines from the EU, including the regulatory framework and the process.

About the PCP process

The three testing laboratories, KOMLAB in Örnsköldsvik, Käppala in Stockholm and Gryaab in Gothenburg had as of mid-May 2016, recieved the test kits from both suppliers: Mancherey-Nagel and ManTech. Initially, tests with the new equipment and with COD(Cr) were performed in parallel each week on both influent and effluent water from several waste water treatment plants (WWTPs). This put the project in Phase 2A, which focused on setting up the equipment, calibration activities, control tests and a smaller test series for validation on real samples with the three competing methods.

1. COD-analysis with chloride elimination from Mancherey-Nagel (CE-COD) 2. COD-analysis with chloride detection from Mancherey-Nagel (CD-COD) 3. PeCOD® from Mantech (PeCOD) 

After a first round of evaluation of the test results from Phase 2A and each method's potential to meet the set criteria, in late August, Phase 2B began.  At this stage, more focus was put on development and adaption of the method to the specific needs at WWTPs stated on the start page. Only CD-COD was invited to continue to Phase 2b and therefor also tested through a durability study, chloride interference study and interlaboratory comparisons.

Results in short

The final report of the project will be published by Upphandlingsmyndigheten shortly. A more in-depth report of the PCP procedure, the method descriptions, laboratory execution and test results will be published by SP Technical Research Institute of Sweden, also in the very near future. 

Chloride detection

The evaluation in Phase 2a indicated that the method had the potential to meet the set criteria in the PCP. Only the results from analyzation on effluent water indicated that a continued development was needed. The accuracy of the method and the correlation to COD(Cr)-method was further shown in Phase 2b to be statistically acceptable on the influent wastewater and proved to be the best alternative out of the three. However on the effluent the evaluation wasn't clear cut and a validation of each sampling point for the effluent testing matrix is needed. The method is mercury free however, not dichromate free. It is ready for commercialization for measurements on influent wastewater. If a sight specific internal laboratory validation is performed on the effluent wastwater and shows acceptable accuracy, it is considered ready to be used here.

Chloride elimination

The required pre-treatment of the sample for this alternative was not applicable in practice, especially on the influent wastewater with the heavier particle load. The results showed the method to give a significant underestimation of the COD-content. The test series for this method was terminated already during Phase 2a.


The PeCOD was tested with both manual and automatic sample feed and preparation. The automatic alternative was shown to be quite problematic for the lab personnel at the start but did eventually work well and was preferable to the manual. The results showed poor statistical accuracy and correlation with the COD(Cr)-method. The method is mercury and dichromate free however, only measures COD on filtered samples. Due to this it did not continue to Phase 2b, considered not to meet the specifications set by the project and the needs of Swedish wastewater treatment plants.