[Effect of Organic Carbon Source on Start-up and Operation of the CANON Granular Sludge Process].

The effect of organic carbon on the start-up and operation of the CANON granular sludge process was investigated in two SBR reactors with different strategies:gradually increased organic carbon concentration (R1) and without organic carbon (R2). The results showed that adding 50 mg·L-1 organic carbon accelerated the start-up of the CANON granular sludge process. R1 and R2 were started up in 23 d and 32 d, respectively. Moreover, the appropriate organic carbon enhanced the activity of AOB, AnAOB, and denitrification, increasing the ammonia removal rates and total nitrogen (TN) removal rates. The maximum ammonia removal rates and total nitrogen removal rates of R1 were 92% and 88%, respectively. The maximum ammonia removal rates and total nitrogen removal rates of R2 were 89% and 80%, respectively. Further tests showed that excessive organic carbon concentration decreased the activity of AOB and AnAOB and reduced the removal efficiency of ammonia and total nitrogen. Adding organic carbon promoted denitrification activity and increased nitrogen removal efficiency.