重金属Cd对污水厂剩余污泥厌氧水解和酸化的影响

在序批式厌氧反应器中探究了重金属Cd~(2+)对污泥厌氧水解和酸化的影响。实验结果表明0.1 mg/L Cd~(2+)能够促进污泥的水解和酸化过程进而促进短链脂肪酸(SCFA)的积累;且其最大积累量为1 025 mg/L。高浓度Cd~(2+)能够促进污泥中有机物的释放;但对酸化过程有严重的抑制作用。当Cd~(2+)的浓度为5.0 mg/L时,最大溶解性化学需氧量(SCOD)和SCFA浓度分别为1 395、465 mg/L,分别是空白对照组的1.5和0.5倍。同时发现高浓度Cd~(2+)(例如5.0 mg/L)能够抑制产甲烷古菌的活性进而导致SCFA的消耗量较低。

Effect of Heavy Metal Cd on Anaerobic Hydrolysis and Acidification of Residual Sludge in Wastewater Treatment Plant

The effects of heavy metal Cd₂₊ on sludge anaerobic hydrolysis and acidification were explored in sequencing batch reactors. Experimental results showed that 0.1 mg/L Cd₂₊ promoted the hydrolysis and acidification process of sludge and caused the accumulation of Short chain fatty acids (SCFA), and the maximum accumulation of SCFA was 1025 mg/L. High concentrations of Cd₂₊ promoted the release of organic matter in the sludge, but have a greater inhibitory effect on the acidification process, when the concentration of Cd₂₊ was 5 mg/L, the maximum solubility of COD and SCFA concentration were 1395 and 465 mg/L,respectively, which was 1.5 and 0.5 times of that in control. Meanwhile, it was found that the high concentration of Cd₂₊ (e.g., 5.0 mg/L) could inhibit the activity of the Methanogenic Achaea, which led to the low consumption of SCFA.