SBR (Sequencing batch reactor) nitrosation quick start method

[0022] The test is based on simulated sewage, and the specific water quality is as follows:

[0023] Influent water quality during startup: NH 4 + -N=300-500mg/L, pH=7.70~8.20, temperature 25±1℃.

[0024] Influent water quality during steady operation of medium ammonia nitrogen: NH 4 + -N=150±15mg/L, pH=7.70~8.20, temperature 25±1℃.

[0025] Influent water quality during stable operation with low ammonia nitrogen: NH 4 + -N=50±5mg/L, pH=7.70~8.20, temperature 25±1℃.

[0026] The specific processing is as follows:

[0027] Operation effect of nitrosated sludge during the startup stage figure 1

[0028] Inoculate the backflow nitrification sludge from the sewage treatment plant into the SBR reactor, control the influent ammonia nitrogen concentration to 300-500mg/L, control the aeration volume to make the dissolved oxygen 0.2-0.5mg/L, control the aeration time to make the ammonia oxidation rate Control at 30%-50%, add sodium bicarbonate to adjust the pH to maintain it at 7.70-8.20. The use of high free ammonia in the water to inhibit NOB, the inhibition of NOB activity by low dissolved oxygen 0.2-0.5mg/L, and the small inhibition of AOB. In addition, it is guaranteed by controlling the ammonia oxidation rate to maintain 30%-50%. Free ammonia always suppresses NOB during each cycle. Under the synergistic inhibition of various conditions, NOB was quickly washed out of the SBR system. by figure 1 It can be seen that the initial nitrification rate of sludge is 18%, and after 4 cycles the nitrification rate has increased significantly to 67%, which reflects that the nitrosation rate has reached 90% in 4 cycles. figure 1 It can be seen that the nitrosation rate has been maintained at more than 90% after running for 7 days and 14 cycles under this condition, marking the successful rapid start of nitrosation.

[0029] The operation effect of nitrosated sludge in the stable operation stage of medium ammonia nitrogen see figure 2

[0030] In the 23rd cycle, change the influent ammonia nitrogen concentration to 150±15mg/L, control the aeration volume so that the dissolved oxygen is 0.5-1.0mg/L, and control the aeration time so that the ammonia oxidation rate is 90%-99%. After 30 days and 60 cycles, the nitrification rate has been maintained at more than 90%, indicating that the nitrosated sludge has good stability under the ammonia nitrogen concentration in the influent water after startup.

[0031] Operation effect of nitrosated sludge during stable operation with low ammonia nitrogen see image 3

[0032] In the 83rd cycle, change the influent ammonia nitrogen concentration to 50±5mg/L, control the aeration volume so that the dissolved oxygen is 0.5-1.0mg/L, control the aeration time so that the ammonia oxidation rate is 85%-95%, After 30 days and 60 cycles, the nitrification rate has been maintained above 90%, indicating that the nitrosated sludge has good stability under low influent ammonia nitrogen concentration after startup.