Morphological characteristics of polyvinyl chloride (PVC) dechlorination during pyrolysis process: Influence of PVC content and heating rate.
In this research morphological techniques were used to characterize dechlorination process of PVC when it is in the mixed waste plastics and the two important factors influencing this process, namely, the proportion of PVC in the mixed plastics and heating rate adopted in the pyrolysis process were investigated. During the pyrolysis process for the mixed plastics containing PVC, the morphologic characteristics describing PVC dechlorination behaviors were obtained with help of a high-speed infrared camera and image processing tools. At the same time emission of hydrogen chloride (HCl) was detected to find out the start and termination of HCl release. The PVC contents in the mixed plastics varied from 0% to 12% in mass and the heating rate for PVC was changed from 10 to 60°C/min. The morphologic parameters including "bubble ratio" (BR) and "pixel area" (PA) were found to have obvious features matching with PVC dechlorination process therefore can be used to characterize dechlorination of PVC alone and in the mixed plastics. It has been also found that shape of HCl emission curve is independent of PVC proportions in the mixed plastics, but shifts to right side with elevated heating rate; and all of which can be quantitatively reflected in morphologic parameters vs. temperature curves.
Thermal & Environmental Engineering Institute, Tongji University, Shanghai 200092, China.
Qiongmin
Q
Cao
Thermal & Environmental Engineering Institute, Tongji University, Shanghai 200092, China.
Guoan
G
Yuan
Thermal & Environmental Engineering Institute, Tongji University, Shanghai 200092, China. Electronic address: y_lijie@tongji.edu.cn.
Lijie
L
Yin
Thermal & Environmental Engineering Institute, Tongji University, Shanghai 200092, China.
Dezhen
D
Chen
State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 200092 Shanghai, China.
Pinjing
P
He
Thermal & Environmental Engineering Institute, Tongji University, Shanghai 200092, China.
Hai
H
Wang
D054879:Halogenation; D006358:Hot Temperature; D006851:Hydrochloric Acid / Q000737:chemistry; D010969:Plastics / Q000737:chemistry*; D011143:Polyvinyl Chloride / Q000737:chemistry*; D012037:Refuse Disposal / Q000379:methods*; D062611:Solid Waste
D010969:Plastics; D062611:Solid Waste; D011143:Polyvinyl Chloride; D006851:Hydrochloric Acid
Dechlorination; Heating rate; Morphological parameters; PVC; Pyrolysis