微波预处理对剩余污泥生化处理的影响

In the present study, microwave was used to pretreat the waste activated sludge. The effect of microwave power and treatment period on sludge disruption, and degradation efficiency of disrupted sludge after the biochemical treatment were investigated. The results showed that when the microwave power increased and the treatment period extended appropriately, the sludge disruption efficiency could be improved and the content of dissolved organic compounds could be increased. Under the optimized condition (microwave power 500 W, treatment period 10 min), the sludge disintegration ratio (ω), the total dissolved nitrogen (TDN), and total dissolved phosphorus (TDP) were 31.0%,179.6 mg•L^-1 and 31.3 mg•L^-1, respectively. The analysis results of infrared spectroscopy showed that the properties of functional groups in sludge were enhanced after microwave treatment. Daily methane production of microwave pretreated sludge was higher that of untreated sludge, cumulative methane production was increased by 45.3%. This result illustrated that the sludge was degraded effectively. After biochemical treatment, the removal rate of chemical oxygen demand (COD) of sludge could reach above 98%, the removal rate of TDP could reach between 80% and 85%, and the TND content of effluent was higher than that of inflow sludge. In conclusion, the technical scheme adopting biochemical treatment of waste activated sludge after microwave pretreatment was feasible.