在线超声清洗对膜生物反应器污泥混合液特性的影响

采用低功率超声波实现了膜生物反应器中膜污染的在线超声清洗,考察在线超声清洗对污泥混合液特性的影响。结果表明:在线超声清洗能有效控制膜污染,但也会导致污泥浓度和污泥活性降低,混合液过滤性能变差,上清液有机物浓度上升,污泥絮体结构破解。污泥混合液特性的恶化必然会影响膜生物反应器的稳定运行,不利于膜污染的控制。为了避免混合液特性过度恶化,每次超声清洗时间应该控制在10 min以内。

EFFECTS OF ONLINE ULTRASONIC CLEANING ON CHARACTERISTICS OF ACTIVATED SLUDGE MIXED LIQUOR IN MEMBRANE BIOREACTOR

The online ultrasonic cleaning was actualized for membrane fouling control in membrane bioreactqr using low power ultrasonic, and its effects on activated sludge mixed liquor characteristics were investigated. The results show that the membrane fouling can be controlled efficiently, but the mixed liquor suspended solid concentration and sludge activity are decreased, the membrane filterability of mixed liquor gets worse, the supernatant organic matter concentration is increased, and the sludge floes are destroyed simultaneously. The deterioration of mixed liquor characteristics is surely to affect the stable operation of MBR, which is not conducive to control membrane pollution. In order to avoid worse characteristics of mixed liquor, the cleaning time should be controlled within 10 min.