| Summary: | 碩士 === 國立中山大學 === 環境工程研究所 === 91 === Abstract
Constructed wetlands can be treated as a imulated natural treatment system,which use solar adiation as the source of energy. By analogy with some removalmechanisms in natural wetlands, constructed wetlands are able to transform and
remove pollutants from the wastewater. Other features provided by the constructed wetland include wildlife support, hydrologic odification, erosion protection, and open space and aesthetics. It has been applied for domestic wastewater purification for decades.
The goal of this study was to evaluate the ffectiveness of using constructed wetlands on industrial wastewater treatment. In this study, grit chamber and furnace waste from steel-making were used as the media for plant growth. Two -tank
(dimension for each tank: 4L ×1W ×1H) system was designed and constructed to simulate the constructed wetland. Reed and cattail were planted in the first and second tanks, respectively. In the system, media in the first and second tanks were filled to a height of 0.4 m (furnace waste from steel-making) and 0.1 m (waste grit), respectively.
The depth of water was maintained at 0.3 m. The hydraulic retention time was approximately 5 days. The following parameters were analyzed during the operational period: nutrients, chemical oxygen demand (COD), suspended solids (SS), and biochemical oxygen demand (BOD). The calculated removal rates (g/m2/day) in the
first tank were：COD 5.92±0.64、BOD 3.48±0.95、SS (suspended solids) 3.42±1.44、TKN (total kjedal nitrogen, TKN) 0.94±0.26、TP (total phosphorus) 1.33±0.2。The removal rates (g/ m2/day) in the second tank were: COD 5.17±0.62、BOD 3.21±0.92、
SS 2.92±1.29、TKN 0.59±0.21、TP 0.66±0.15.
Results from this study indicate that the media and plants in both tanks created a biofiltration system for microbial growth and pollutant removal. Sorption and biodegradation were the two major pollutant removal mechanisms in the system.
During the operational period, the average removal efficiencies (%) in the first tank were: COD 55~62, BOD 73~90, SS 66~84, TKN 36~66, TP 28~39. The average removal efficiencies (%) in the first tank were: COD 49~54, BOD 73~83, SS 45~69,TKN 15~43, TP 9~24.
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