Abstract
Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic organic pollutants. Because of their highly hydrophobic property, PAHs easily absorbed by organic matters. They also display highly biological accumulation ability and toxicity. PAHs can interrupt organism¡¦s endocrine systems and some are considered bearing mutagenic or carcinogenic potentialities. Because of industrialigation, the extent of accumulated PAHs in the environment at present is significantly higher than those in the past. Therefore, while it is best to avoid further producing of these compounds if at all feasible; efforts to limit the introduction of these compounds into the environment by treating point pollution sources should always be made.
The traditional approach to treat organic pollutants, including PAHs, in wastewater is mainly microbial based degradation. But recently due to its low cost and relatively high efficiency, treatment using aquatic plants combined with microbial degradation became popular. However, there have not much work done in using aquatic plant alone to treat PAHs. To study the sorption of PAHs by aquatic plant can provide information regarding the role of plant and microbial actions, and to enable such bioremediation technology more flexibile and feasible in application. Therefore, the forcus of this research is using plant solely to remove PAHs in a man-made wastewater.
In this study, an aquatic plant, Ceratophyllum demersum, was used to sorb phenanthrene (Phe) with a continuous flow device. The competition effect in sorption by another PAHs, pyrene (Pyr), was also studied. In addition, another aquatic plant, Naja gramunea Del., was tested using the same system.
In the batch experiment, the sorption kinetic constants of phenanthrene and pyrene for Ceratophyllum demersum are 0.19 and 0.22, respectively. Compared with Ceratophyllum demersum, Naja gramunea Del. has a higher kinetic constant. The sorption equilibrium constants of phenanthrene and pyrene for Ceratophyllum demersum are 1.36 and 19.24, respectively. Compared with Naja gramunea Del., Ceratophyllum demersum has a higher equilibrium constant for phenanthrene, but with a lower equilibrium constant for pyrene.
A competition effect was observed by the delayed phenanthrene¡¦s saturation time by using pyrene as the possible background pollutant in the continuous flow system. Naja gramunea Del. was also applied in the same system for treating phenanthrene and pyrene in the same way. In conclusion, these two aquatic plants demonstrated great potentials in applications used for treating wastewaters containing PAHs due to low energy and cost of the device.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0706105-180202 |
| Date | 06 July 2005 |
| Creators | Hsu, Sheng-shiung |
| Contributors | C. H. Lai, Chon-Lin Lee, Michael Hin-Kiu Mok, C. H. Chen |
| 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-0706105-180202 |
| Rights | off_campus_withheld, Copyright information available at source archive |
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