摘要：Due to the high viscosity and stickiness of dehydrated sludge, the combination of foaming pretreatment and drying process is an effective method to improve the drying performance of dehydrated sludge. In this study, alkali and industrial lignin fiber addition followed by mechanical whipping was employed for foaming the dewatered sludge. Using alkali alone as foaming agent, the optimal NaOH addition was found at 2.5 wt%, which was superior to adding CaO. Considering the maximum foaming efficiency, 2% industrial lignin fiber FH-300 collected as a conditioner and 1% NaOH was optimal. The foams in dewatered sludge were highly stable. The total number of bubbles of sludge with different densities had big differences. The diameters of bubbles concentrated on the range of 0.1 mm-0.3 mm.
