| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technology to relatively easily and inexpensively biologically remove nitrate nitrogen in a relatively low concentration of not more than the environmental standard (≤10 mg/L) contained in river water by obtaining the temperature variation generated due to the seasonal fluctuation. <P>SOLUTION: The method for removing nitrogen compounds in a water to be treated by a biological nitrogen removal method including adding, for example, a soap as nutrient salts necessary for the metabolism of denitrifying bacteria to the water to be treated and using the denitrifying bacteria. The correlation data among the temperature of the water to be treated, the amount of the soap added and the concentration of nitrogen compounds is prepared in advance. The temperature of a water to be treated and the concentration of nitrogen compounds are measured and the actual measurement values are designated on the correlation data to thereby determine an adequate addition amount of the soap. The actual addition amount of the soap is regulated to become the adequate addition amount, and then, the nitrogen compounds are removed until the concentration of the nitrogen compounds in the water to be treated becomes a target concentration. <P>COPYRIGHT: (C)2012,JPO&INPIT |
