| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for controlling a complex process which can always obtain a high nitrogen removing rate even when the quality and temperature of water are changed in order to solve the problem that, although there are an ammonia stripping method and an activated sludge method for treating stockbreeding wastewater or industrial wastewater containing a high concentration of ammonia, a control technology for nitrogen removing treatment is not yet established, and the denitrification velocity of an activated sludge tank is decreased by the lowering of the temperature of water in the activated sludge tank and the decrease in the concentration of organic substances in ammonia stripping treatment water to cause the increase in the concentration of nitrogen in treatment water. SOLUTION: The temperature of water in the activated sludge tank or the concentration of nitrate nitrogen is measured. When the temperature of water is low, or the concentration of nitrate nitrogen is high, the amount of steam to be supplied to an ammonia stripping apparatus in a pre-stage is increased automatically to increases a nitrogen removing rate. The nitrogen load in the activated sludge method in a post-stage is controlled to be reduced so that the nitrogen removing capacity of the whole complex process can be kept constant.</p> |
