1. Dejun Bian, Wenhua Zhang, Beisheng Long: The waste water treatment plant of micro pressure Internal Circulation activated sludge [P]. The Patent of china: CN2603079 (In Chinese).
2. Xi Tian, Liguo Wan, Dejun Bian: Environmental Science Technology Vol. 33 (6E) (2010), p.374 (In Chinese).
3. Hua Dong, Wei Lu: Water Protection Vol. 3 (1997), p.43 (In Chinese).
4. NEPA: Monitoring and Analysis Method of Water and Wastewater[M]. Beijing: China Science and Technology Publishing House(2002), p.210 (In Chinese).
5. Vidal G, Nieto J , Cooman K, Gajardo M , Bornhardt C: Journal of Hazardous Materials Vol. 112 (1/ 2) (2004), p.143.