不同pH控制策略下剩余污泥中NH4^＋-N、PO4^3--P、COD溶出研究

污水处理厂的剩余污泥中富含氮、磷、COD,在其水解酸化过程中对pH条件进行控制,使污泥中的氮、磷、COD溶出到上清液中并进行回收利用是可行的。在22～25℃的温度条件下,1#反应器中剩余污泥先调节为酸性（pH=3）,在实验第8 d氨氮、磷酸盐溶出量最多后调节为碱性（pH=10）;3#反应器中剩余污泥先调节为碱性（pH=10）,在实验第8 dCOD溶出量最多后调节为酸性（pH=3）;2#反应器为对照实验,pH不进行调节。结果表明：若要以回收污泥中的氨氮、磷酸盐为主,剩余污泥由碱性（pH=10）调节为酸性（pH=3）优于由酸性（pH=3）调节为碱性（pH=10）;若要回收污泥上清液中的COD为主,剩余污泥由酸性（pH=3）调节为碱性（pH=10）优于由碱性（pH=10）调节为酸性（pH=3）。

Study on release of ammonium,phosphorous and COD from excess sludge with different pH control strategies

The sludge in sewage treatment plant is rich in nitrogen,phosphate and COD.The pH was controlled in the hydrolytic acidification process to make ammonium,phosphate and COD released into the supernatant fluid.It is available to get ammonium,phosphate and COD recovery from sludge.At 22～25℃ the sludge in 1# reactor firstly was adjusted to acid（pH=3）.When the optimal release quantity of ammonium,phosphate was got on the 8th day,the sludge was adjusted to alkaline（pH=10）.The sludge in 3# reactor firstly was adjusted to alkaline（pH=10）.When the optimal release quantity of COD was got on the 8th day,the sludge was adjusted to acid（pH=3）.The 2# reactor was comparative trial and the pH in it was not adjusted.The results showed that when the ammonium,phosphate were retrieved mainly,the sludge adjusted process from alkaline（pH=10） to acid（pH=3） had advantage of the process from acid（pH=3） to alkaline（pH=10）.When COD was retrieved mainly,the sludge adjusted process from acid（pH=3） to alkaline（pH=10） had advantage of the process from alkaline（pH=10） to acid（pH=3）.