Proceedings 會 刊 - SCCAEPA SPONSORS

College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004,
P.R. China Email: zhangxuehong@ x 263.net, liujie@glite.edu.cn, zenghonghu@glite.edu.cn,
wangdunqiu@glite.edu.cn, zqwu@glite.edu.cn
Abstract: The constructed wetlands planted with Leersia hexandra Swartz (CWL) in pilot scale were
used to treat electroplating wastewater containing Cr, Cu and Ni. Effects of surface loading rate (SLR)
and initial metal concentrations on removal of Cr, Cu and Ni were studied. It was found that CWL
significantly reduced the concentrations of Cr, Cu and Ni in wastewater by 84.4%, 97.1% and 94.3%,
respectively. High SLR decreased the removal efficiencies of Cr, Cu and Ni, however, the heavy metal
concentrations in effluent met Emission Standard of Pollutants for Electroplating in China (ESPE) with the
SLR less than 0.3 m3/ m2 d. For the influent of 5 mg/L Cr, 10 mg/L Cu and 8 mg/L Ni, effluent
concentrations were below maximum allowable concentrations in ESPE, indicating that removal of Cr, Cu
and Ni by CWL was feasible at considerable high influent metal concentrations. Mass balance showed
that the primary sink for the retention of contaminants within the constructed wetland system was the
sediment, which accounted for 59.5 %, 83.5 %, and 73.9 % of the Cr, Cu, and Ni, respectively. The data
from the pilot wetlands support the view that constructed wetlands planted with L. hexandra could be
used to successfully remove Cr, Cu and Ni from electroplating wastewater.
Keywords: Constructed wetland; Leersia hexandra Swartz; Cr; Cu; Ni
Renovation of used lithium cobalt oxide from lithium ion rechargeable battery by ultrasonic
irradiation
Zheming Zhang, Wenzhi He*, Jing Xia, Guangming Li, and Juwen Huang
Tongji University, No 1239, Siping road, Shanghai, CHINA. 200092, *Corresponding author: Wenzhi
He Tel:13564753913, Email: hithwz@163.com
Abstract: Lithium-ion battery (LIB) is widely used as electrochemical power sources in mobile telephones
and other modern-life appliances. As a result, huge amount of spent LIBs are generated. Recycling of
LIBs has increasingly become important because their unsafe disposal will cause a serious problem due
to the presence of flammable and toxic elements or compounds. Economic benefits could be achieved in
recovery of major components from LIBs, especially for cathode materials LiCoO2. The effective recycling
and reusing of spent LIBs has good environmental and economic benefit. Ultrasonic renovation can
significantly improve the treating efficiency of precious components in spent LIBs.
This work proposes a new process for renovating cathode materials LiCoO2 from spent LIBs in LiOH
by ultrasonic hydrothermal reaction. The ultrasonic cavitation can provides partial higher temperature and
voltage and hydroxyl radical which has strong oxidability. In order to get the best renovation effect, the
optimal reaction condition was selected: 10 grams LiCoO2 with 2 mol of LiOH, 120°C, the ultrasonic
power is 999W and ultrasonic method is “work 5S-stop 2S” and ultrasonic radiation for 10 hours.
Through X-Ray Diffraction, scanning electron microscopy, ICP-AES and charge-discharge analysis, the
results showed that the renovated LiCoO2 had high degree of crystallinity, fine layered structure, good
dispersion of particles and improved electrochemical cycle performance. Finally, the renovated LiCoO2
under optimal operating conditions was assembled into button battery and its charge and discharge
performance of the renovated LiCoO2 was 132.6 mAh/g and 131.5 mAh /g respectively. The first-time
charge and discharge efficiency was 99.2%. After 20 times of cycling, the discharge capacity retention
rate was 98.1% which could reach electrochemical properties of commercial batteries. This process is
feasible for recycling spent LIBs in scale-up.
Keywords: Spent lithium-ion batteries, LiCoO2, renovation, Ultrasonic reaction
Effect of short-time aerobic digestion on bioflocculation of extracellular polymeric
substances from waste activated sludge
Zhiqiang Zhang1 Jiao Zhang2 Xiangrong Li1 Siqing Xia1
张 志 强 1 张 姣 2 李 向 蓉 1 夏 四 清 1
1 State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science
and Engineering, Tongji University, Shanghai 200092, China; 2 School of Civil Engineering and
Transportation, Shanghai Technical College of Urban Management, Shanghai 200432, China; Email:
zhiqiang@tongji.du.cn, ggglg@163.com, lixr872@126.com, siqingxia@tongji.edu.cn
Abstract: The effect of short-time aerobic digestion on bioflocculation of extracellular polymeric
substances (EPS) from waste activated sludge (WAS) was investigated. Bioflocculation of the EPS was
found to be enhanced by 2~6 h WAS aerobic digestion under the conditions of natural sludge pH (about
7), high sludge concentration by gravity thickening, and dissolved oxygen (DO) about 2 mg/L. With the
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