Case Study – Thomayer University Hospital: Quaternary Wastewater Treatment at the WWTP

Efficiency at commissioning

When the technology was commissioned in 2024, the removal efficiency of the monitored pharmaceutical compounds exceeded 99%.

Long-term performance after 16–18 months of operation

The evaluation is based on detailed monitoring carried out over a three-month period as part of the company’s research and development project RV250004.

Key technologies: Microfiltration, ozonation, and granular activated carbon (GAC) filtration.

Evaluation according to EU Directive 2024/3019 (12 indicator substances)

• During the monitoring period (16–18 months of operation), the technology achieved excellent removal efficiency of 99–100% for all 12 monitored indicator substances.
• The highest input concentrations were detected for 1H-benzotriazole, which was removed with 99% efficiency.
• GAC filtration consistently removed 55–60% of the remaining residues, most likely due to biodegradation processes.
• The WWTP operates with a substantial performance reserve, as the Directive requires a minimum removal efficiency of 80% for each monitored substance.
• Replacement of the GAC is not yet required, and there is potential to optimise (reduce) the ozonation intensity to lower energy consumption.

Evaluation based on an extended set of 115 pharmaceuticals

Overall removal efficiency of the quaternary treatment stage: 81–86%

The following substances dominated in the treated water:

• X-ray contrast agents (considered biologically inactive)
• Metformin

Downstream of the GAC filtration stage, metformin concentrations were higher than those measured after ozonation, indicating that replacement of the GAC media should be considered. The removal of metformin and its persistent metabolite, guanylurea, in wastewater treatment plants, as well as their environmental impacts, is currently the subject of ongoing research in several countries.

Summary of the technology benefits

• First full-scale installation of its kind in the Czech Republic.
• Proven high efficiency in removing pharmaceutical compounds.
• Full compliance with current European regulatory requirements, with a substantial performance reserve.
• Potential for energy optimisation and long-term sustainable operation.

Our technology featured on Czech Television

In April 2026, our quaternary treatment technology was featured in a report by Czech Television.You can watch the report at the 34-minute mark and learn more about the technology and its practical application.