The purpose of this study is to use vertical-flow constructed wetlands (VFCW) microcosm systems to investragte the removal efficiencies of sulfate. The system was located on the campus sewage treatment plant. nn National Sun Yat-sen University. In this study, two media, gravel and peat, were installed in four different systems. The two system with same media were separated into vegetated and non-vegetated (control) ones respectively. In the test runs, the operation methods included batch type filled with water, continuous flow and integrated vertical flow constructed wetland (IVCW) with continuous flow. In batch type test, it was run under an initial concentrations of SO42--S about 500 mg/L. The experimental results showed that the removal efficiencies were increased with increasing COD concentrations. Under the same conditions but with continuous flow operation, the removal efficiencies of SO42--S were lower than the batch type one, which 80% could be reached. The best system for operation was P1 (peat with vegetated), in which the removal effciency reached 90%. The experimental results also showed that the vegetated systems presented higher removal efficiencies of sulfate than the non-vegetated ones. In addition, this research were increased the concentrations of SO42--S and COD to about 1200 mg/L and 4000 mg/L respectively. The experimental results showed that the IVCW treatment system could achived greater efficiency than VFCW treatment system.
The experimental in depth research test run indicated that the anaerobic condition did not affect the removal efficiencies of ammonia by using batch type. However, nitrification was the main reaction of ammonia to nitrate in the continuous flow type systems. When ORP values were found below the -300 mV, the sulfate began to be drcreased. It was believed that if the anaerobic condition were well be established, while the organic carbon could be contented in this system, the sulfate reducing bacteria (SRB) might live, and then sulfate could be removed.
The effect of temperature on sulfate removal was generally established in this study. According to the experimental results, it was found that the activity of SRB motility was higher in higher temperature (35¢J) than that in lower temperature (25¢J).
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0722110-122215 |
| Date | 22 July 2010 |
| Creators | Chung, Chia-chi |
| Contributors | Wen-chien Kuo, Lei Yang, Chih-ming Kao |
| 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-0722110-122215 |
| Rights | unrestricted, Copyright information available at source archive |
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