When the pH-value is within set limits, the wastewater flows freely through the neutralizing well. If the pH-value changes so that it either goes below or exceeds the set limit, the outlet valve is closed and water starts to collect in the well. At this point also the mixer and the acid/base feeder are activated. Once the well is full and the pH-value is within permissible limits, the closing valve opens and the liquid can be led to the sewer. The valve stays open unless the water entering the well requires neutralization. PH-automatics and a SET level detector control the operating of the system.
