城市湖泊水环境修复组合工艺效果研究——以深圳市荔枝湖治理工程为例

以深圳市荔枝湖为例,通过历时9个月的水质连续监测,研究该湖水污染综合治理工程实施后不同治理工艺的处理效果.研究表明,自动过滤工艺TP和COD平均去除率分别为33.6%和16.2%;生物砾石床工艺TP和COD平均去除率分别为39.O%和21.3%;人工湿地工艺TP和COD平均去除率分别为80.2%和56.1%.通过荔枝湖四湖总磷串联模型,计算在设计初始条件下,采用组合治理工艺时湖水恢复为地表Ⅳ类水所需要的时间.计算表明工艺每天运行24h,需要2.5d可将各湖TP浓度降至O.1mg/L以下,TP总去除量为7.27kg,去除率为46.%.

Investigation on effect of treatment units in restoration project for urban lakes——a case study of Lake Lichee in Shenzhen

The integrated restoration project in Lake Lichee in Shenzhen, China, is taken as a case study to investigate the treatment effect of the different units in the restoration project based on 9 months', field monitoring data. The results showed that, the mean removal rates were 33.6% for TP and 16.2% for COD via a filtration unit; 39.0% for TP and 21.3% for COD via a bio-gravel-layer unit; and 80.2% for TP and 56.1% for COD via a man-made wetland unit. A total phosphorus modeling of each sub-lake for Lake Lichee was developed and applied to compute time needed to improve water quality to match Grade IV of surface water standard under the designed conditions. The result showed that it will take 2.5d subject to 24h operation of the restoration project per day to reduce TP concentration lower than 0.1mg/L in Lake Lichee. During the process, TP removal load is about 7.27kg, and the removal rate is almost 46.9% in Lake.