REJEKTVATTENBEHANDLING MED OMVÄND OSMOS / Reject Water Treatment with Reverse Osmosis
In water with high levels of nitrogen, it can be of interest to use reverse osmosis for removal of the nitrogen. This can help to reduce the total load of the wastewater treatment plant. To improve removal of nitrogen, high pressure can be used to press the nitrogen-water through a reverse osmosis membrane. The nitrogen will remain in the concentrate, which will become more and more concentrated. The water will go through the membrane as permeate. In cooperation with IVL in Stockholm some trials has been made by reverse osmosis on rejectwater from digested sludge from Skebäcksverket in Örebro. The nitrogen-content in the water is 1-1.5 kg NH4-N/m3. In pilotscale was 90 % separation efficiency achieved. At the same time the separation efficiency on all others contaminating elements was high. For the best effect, the water may be pretreated, if there is high levels of suspended solids. “Complete abstract not presented.”