非均相臭氧催化氧化对污泥脱水性能的影响

Effect of heterogeneous catalytic ozonation on sludge dewaterability

臭氧氧化技术是一项具有应用前景的新型污泥减量技术,但臭氧处理会导致污泥脱水性能恶化,影响后续处理处置,需要其他技术或手段的辅助以提高污泥脱水性能.以市政剩余活性污泥为原料,采用FeOOH、Fe_(2)O_(3)、TiO_(2)、MnO_(2)、Al_(2)O_(3)粉、Al_(2)O_(3)球、果壳活性炭、椰壳活性炭、粉质炭、煤质炭、铜丝等11种非均相催化剂开展污泥的非均相臭氧催化氧化实验,研究污泥脱水性能的变化.结果表明,在11种非均相催化剂中,TiO_(2)、Fe_(2)O_(3)、Al_(2)O_(3)球、铜丝、FeOOH、粉质炭能够显著抑制臭氧处理对污泥脱水性能的恶化作用,其中FeOOH、粉质炭和铜丝效果最佳.在FeOOH、粉质炭和铜丝催化臭氧氧化体系中,22.50 mg·L^(-1)臭氧为较优浓度,浓度过低或过高均不利于污泥脱水性能的改善.3种催化剂中,FeOOH催化臭氧氧化对低含固率(0.5%和1%)污泥的脱水性能有明显的改善效果.FeOOH投加量的增加有利于在较短的反应时间内改善污泥的脱水性能.向含固率为0.5%的污泥中投加300 mg·g^(-1)DS FeOOH、37.95 mg·L^(-1)臭氧,污泥的CST可在5 min内下降21.1%.FeOOH催化臭氧氧化是一种有前景的强化污泥脱水性能的方法.

Ozonation is a promising technique for sludge minimization,but it also leads to the deterioration of dewaterability,hindering the subsequent treatment and disposal.To improve the sludge dewaterability,heterogeneous catalytic ozonation was adopted in this study,using 11 kinds of catalysts,including FeOOH,Fe_(2)O_(3),TiO_(2),MnO_(2),Al_(2)O_(3) powder,Al_(2)O_(3) ball,nut shell activated carbon,coconut shell activated carbon,powdered activated carbon,coal based activated carbon,and copper wire The dewatering performance of sludge was evaluated.Results show that among the 11 catalysts,TiO_(2),Fe_(2)O_(3),Al_(2)O_(3) ball,copper wire,FeOOH,and powdered activated carbon could significantly inhibit the deterioration of sludge dewaterability caused by ozonation,and FeOOH,powdered activated carbon,copper wire performed the best.During ozonation treatment catalyzed by FeOOH,powdered activated carbon and copper wire,22.50 mg·L^(-1) was a suitable ozone dosage,and a higher or lower dosage was adverse to the improvement of sludge dewaterability.Among the 3 catalysts,FeOOH catalyzed ozonation could dramatically improve the dewatering performance of sludge with low solid content(0.5% and 1%).Increase of FeOOH dosage was beneficial to improve the dewatering performance of sludge in a short reaction time.The CST of the sludge(solid content 0.5%)reduced 21.1% in 5 min when FeOOH(300 mg·g^(-1) DS)catalyzed ozonation(37.95 mg·L^(-1))was applied,suggesting that it is a promising method to enhance the sludge dewatering performance.