Ultrapure water with lower operating costs

Maabjerg Energy Center in Denmark is a combined heat and power plant using waste and biomass providing a generation capacity of 28 MW. Since its commissioning in 1993, a water treatment plant, consisting of a reverse osmosis plant (RO) with subsequent service-regenerated mixed-bed, has produced deionate for the power plant's high-pressure boiler. Due to high operating costs at the existing water treatment plant, it was decided to look into a new solution.                                                                      

The solution was a double-pass reverse osmosis system (DPRO), followed by an EDI system, as well as two EUREX mixed-bed systems in series. The upgrade from single-pass to a double-pass system resulted in a much better operation of the EDI system, which resulted in significantly longer operating time between regenerations for the subsequent EUREX mixed-bed system. At the same time, it has been possible to replace the use of NaOH to remove CO2 from the water by using a membrane degasser - a 100 % chemical-free solution. This resulted in a 90% reduction in operating costs.

To avoid operational disruptions during the replacement of the old plant, a container solution with a mobile water treatment plant was established. It provided a smooth replacement and even a temporary improvement in operation and control compared to the existing plant.