The objective of this study was to remove mercury vapor from municipal waste incinerator (MWI) by the adsorption of powder activated carbon (PAC) prepared from the pyrolysis of waste tire. The study focused on the measurement of mercury concentration in flue gas emitted from municipal waste incinerator, the preparation of PAC from the pyrolysis of the waste tire and impregnated with sulfur, and the adsorption capacity of mercury by the self-made PAC.
The measurement of heavy metals in flue gas emitted from four typical MWIs was conducted in this study. Experimental results obtained from the measurement of mercury from flue gas indicated that the removal efficiency of mercury ranged from 83.71%~96.22%for the tested MWIs. This study revealed that the injection of PAC in flue gas would enhance the removal efficiency of mercury. Besides, oxided mercury (Hg2+) can be removed much more easily than elemental mercury (Hg0).
Experimental results obtained from the pyrolysis of waste tires indicated that the pyrolysis temperature of waste tire was approximately 400~500¢J, and the percentage of carbon residue is 35~37%. With higher temperature and water feed rate and longer activation time, the specific surface area and total pore volume of PAC increased while the average pore radius decreased. The highest specific surface area of PAC obtained in this study was 996 m2/g. In addition, experimental results obtained from sulfur impregnation process indicated that the specific surface area of PAC decreased dramatically as sulfur was added to PAC.
Experiment results obtained from the adsorption capacity of HgCl2 on PAC by column test indicated that PAC with higher specific surface area could adsorb more HgCl2 at room temperature (25¢J). The adsorption capacity of sulfur impregnated PAC decreased at 25¢J was due to the decrease of specific surface area of PAC. However, results from the comparison of two PAC with similar specific surface area indicated that the PAC with higher sulfur content had higher adsorption capacity. It suggested that the addition of sulfur to PAC could enhance the adsorption of HgCl2 at 25¢J. Experimental results obtained from column tests at 150¢J showed that the adsorption capacity of PAC increased as sulfur content of PAC increased. These results suggested that the adsorption mechanism of HgCl2 by PAC was mainly physical adsorption at lower temperature and it was chemisorption at higher temperature. Besides, the self-made PAC demonstrated the similar adsorption capacity of HgCl2 with commercial PAC used in MWIs.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0801100-064036 |
| Date | 01 August 2000 |
| Creators | Wu, Chun-Hsin |
| Contributors | Chung-Hsing Wu, Chung-Hsuang Hung, Kang-Shin Chen, Chung-Shin Yuan, Tsair-Fuh Lin |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0801100-064036 |
| Rights | unrestricted, Copyright information available at source archive |
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