Selective release of phosphorus from waste-activated sludge by low-temperature thermal treatment: comparative study with ultrasonic treatment

作者：Kim Minwook; Kim Dong Jin^*

来源：Desalination and Water Treatment, 2016, 57(1): 24109-24115.

DOI：10.1080/19443994.2016.1145954

• Low-temperature thermal treatment
• Phosphorus recovery
• Selective phosphorus release
• Ultrasonic treatment
• Waste-activated sludge

Phosphorus (P) is a limited and irreplaceable resource and its recovery has become critical for sustainable society. Waste-activated sludge (WAS) is an important source for P recovery. For selective release of P, thermal treatment at low temperature (50-80 degrees C) was applied to WAS and the release characteristics of P, nitrogen (N), and organic compounds were investigated. Thermal treatment showed that P release is positively associated with temperature and treatment time. Thermal treatment of sludge at 50-80 degrees C released 25-32% of total P (T-P) in 2h. Inorganic phosphate (Pi) release was 19-22% of the T-P in the sludge, while polyphosphate (poly-P) release was 2-9% of the T-P at 50-80 degrees C. Pi was the dominant P compound (85% of the released T-P) in the supernatant at 50 degrees C and its proportion decreased to 56% at 80 degrees C, while the proportion of poly-P in the supernatant increased at higher temperature. During the initial 30min of thermal treatment at 50 degrees C, the amount of released N exceeded that of P at 80 degrees C. However, P was the major compound released after 2h, followed by N and organic compounds. On the other hand, ultrasonic treatment of WAS showed no preferential release of specific compound and proved the selective release of P with low-temperature thermal treatment.

• 出版日期2016-11