Method for realizing SBR nitrosation-denitrosation at low temperature by optimally controlling aeration time

The invention discloses a control method for realizing nitrosation-denitrosation of ammonia nitrogen wastewater at a low temperature by a sequencing batch reactor (SBR) method. Based on the conventional facultative anaerobic-aerobic intermittent activated sludge method, pH, oxidation-reduction potential (ORP) and dissolved oxygen (DO) are used as real-time monitoring parameters to establish an automatic control system in the method. The oxidation of nitrite is suppressed by controlling concentration of free ammonia (FA) in a reactor system at the temperature of between 10 and 18 DEG C, or the aeration time is optimally controlled according to an ammonia valley point on a pH real-time curve, so that high-concentration ammonia nitrogen wastewater is treated by nitrosation-denitrosation. By the method, the nitrosation rate can reach 80 percent, and the removal rates of TN, NH3-N and chemical oxygen demand (COD) reach over 95 percent, 99 percent and 90 percent respectively.