Advanced water treatment for the pharmaceutical residues at a ski resort plant
Introduction.
In this project, we are visiting a large water treatment plant in one of Sweden’s many municipalities.
The water treatment plant is located in close proximity to a popular ski resort. As such, there are drastic variations between the seasons when it comes to treating wastewater: there are differences in flow, amount of nutrients, and amount of micropollutants. These variations are something that we at Mellifiq had to take into careful consideration in this project.
The problem.
The EU has recently revised its Urban Wastewater Treatment Directive so that it now includes treatment demands for pharmaceutical residues, APIs. This concerns all large treatment plants and areas with sensitive recipients.
In order to comply with the upcoming regulations, a fourth advanced water treatment step has to be implemented. As mentioned previously, this municipal treatment plant has to take significant flow and nutrient variations into consideration. This makes for a particularly challenging and complex situation when you need to design a full-scale treatment process.
The solution.
To evaluate how our proposed advanced wastewater treatment performed both in high season and in low season, a modular containerized pilot system was installed at the treatment plant.
Parts of the outgoing water flow were treated using several technical solutions in combination, for a total of three treatment steps: sand filtration using our Water Maid FlexKarb system, ozone oxidation using our Ozonetech RENA Tellus system, and adsorption using granulated activated carbon (GAC). The pilot system was installed at the outlet of the treatment plant, which is where a full-scale quaternary treatment plant would be placed as well.
Through this pilot project, we at Mellifiq managed to optimize the advanced water treatment process aimed at taking care of active pharmaceutical ingredients (APIs), whether it be in high season or in low season. The project was evaluated for 6 months; over the course of this period, the system went through different process scenarios and we collected samples regularly in order to optimize the treatment efficiency and energy consumption.
Evaluation.
The results showed high variations in API concentrations between high and low season, as expected, and so, based on the pilot project, we designed a full-scale treatment plant.
This advanced water treatment system managed to reduce API substances by up to 99%, all while handling flows of up to 1 000 m³/h. The plant managers are very satisfied with their new treatment solution that is environmentally friendly, chemical-free and energy-efficient!