微波辐射对脱水城市污泥穿透性和脱水性的影响

研究了频率2450 MHz、功率500 W的微波在脱水城市污泥中的穿透性及辐射过程中污泥脱水性的变化. 结果表明，微波的穿透深度为8.7 mm，适宜的辐射可显著提高污泥的脱水性. 微波辐射5 min，上层容器中污泥离心后含水率由80.61%降至75.09%. 当温度高于约60℃时，污泥中微生物细胞开始大量破碎，胞内水释出，离心后含水率随温度升高而降低；高于88℃时，胞外聚合物含量无明显增加而亲水性下降，污泥脱水性迅速改善.

Effect of Microwave Irradiation on the Penetrability and Dewaterability of Dewatered Municipal Sewage Sludge

The penetrability of microwave at the frequency of 2450 MHz and the power of 500 W was studied in dewatered municipal sewage sludge, and the change of dewaterability of sludge was also studied in the process of microwave irradiation. The results showed that the penetration depth of microwave was 8.7 mm, and the dewaterability of sludge could be improved obviously by proper irradiation. The water content of sludge after centrifugation in the top container was decreased from 80.61% to 75.09% after the sludge was treated for 5 min by microwave irradiation. When the temperature was above about 60℃, microbial cells in sludge began to be broken in large quantities and the intracellular water was released, and the water content of sludge after centrifugation decreased with increasing temperature. When the temperature was above 88℃, the concentrations of extracellular polymeric substances (EPS) had no obvious increase but the hydrophilicity of EPS decreased, and the dewaterability had the quick improvement.