A novel method was applied to co-recover proteins and humic acid from the dewatered sewage sludge for liquid fertilizer and animal feed. The proteins in sewage sludge were first extracted using the processes of ultra-...A novel method was applied to co-recover proteins and humic acid from the dewatered sewage sludge for liquid fertilizer and animal feed. The proteins in sewage sludge were first extracted using the processes of ultra- sonication and acid precipitation, and then the humic acid was recovered via membrane filtration. The extraction efficiency was 125.9mg humic acid-gWSS volatile suspended solids （VSS） and 123.9 mg proteins-g-1 VSS at the optimal ultrasonic density of 1.5 W·mL-1. FT-IR spectrum results indicated that the recovered proteins and humic acid showed similar chemical characteristic to the natural proteins and humic acid. The acidic solution （pH 2） could be recycled and used more than 10 times during the co-recovery processes. In addition, the dewatered sludge could be easily biodegraded when the humic acid and proteins are extracted, which was essential for further utilization. These findings are of great significance for recovering valuable nutrient fi＇om sewage sludge.展开更多
基金This research was supported by National Nature Science Foundation of China （Grant No.51408159）, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology （No. 2013TS03）, and the China Postdoctoral Science Foundation funded projects （Nos. 2013T60375 and 2012M520744）.
文摘A novel method was applied to co-recover proteins and humic acid from the dewatered sewage sludge for liquid fertilizer and animal feed. The proteins in sewage sludge were first extracted using the processes of ultra- sonication and acid precipitation, and then the humic acid was recovered via membrane filtration. The extraction efficiency was 125.9mg humic acid-gWSS volatile suspended solids （VSS） and 123.9 mg proteins-g-1 VSS at the optimal ultrasonic density of 1.5 W·mL-1. FT-IR spectrum results indicated that the recovered proteins and humic acid showed similar chemical characteristic to the natural proteins and humic acid. The acidic solution （pH 2） could be recycled and used more than 10 times during the co-recovery processes. In addition, the dewatered sludge could be easily biodegraded when the humic acid and proteins are extracted, which was essential for further utilization. These findings are of great significance for recovering valuable nutrient fi＇om sewage sludge.
