Andesite as a filter in the constructed wetland to process the effluent water of hospital

• Main Authors: Yu-Fu Liu, 劉昱甫
• Other Authors: Wing-Ping Liao
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/40073542379776612416

碩士 === 國立中興大學 === 環境工程學系所 === 100 === Abstract Constructed wetlands are designed and regulated by human to simulate the mechanism of water purification in natural wetlands in order to remove the water pollutants by the interaction of wetlands mediums, water, plants and microorganisms associating with physical, chemical, biological and other mechanisms. This is an economic ecological engineering method to reduce water pollutants. In this study the subject selected was domestic wastewater, combing an in-series constructed wetland for a small-scale tertiary wastewater treatment plant to further process the removal of contaminants from the wastewater, reduce the pollution loading on receiving waters after releasing. The device was placed in the sunny outdoors, well-installed to protect from the rain, equipped with Free Water Surface Constructed Wetland (FWS) and Subsurface Flow (SSF). Also, the tanks were stuffed with soil, Porphyritic Andesite and planted with cattails. We applied gravity flow to conduct water, used an valve to control the water incoming. The operation period was from March 21st 2011 to June 7th 2011, divided into three Hydraulic Retention Time (HRT) phases. The retention times were 4.2 days, 2 days and 1 day, respectively. On these occasions, here are the data related to removal percentages of the following pollutants, applied by the wetland system: 93%, 84% and 87% in Suspended Substance (SS); 87%, 87% and 87% in Biological Oxygen Demand (BOD); 99%, 84% and 27% in Total Phosphorus (TP); 99%, 99% and 99% in amino nitrogen (NH3-N); 99.7%, 47% and 21% in nitrate (NO3-) as well as 99.4%, 99.6% and 99.7% in coliform. Finally, we plan to combine the small sewage treatment plant with constructed wetland as a reference to build an actual size, in order to meet the demand but under the regulation for water quality standards control, as an evaluation. Keywords：domestic wastewater 、Subsurface Flow、Free Water Surface Constructed Wetland、Porphyritic Andesite