MICRO-POLLUTED LAKE WATER TREATMENT BY A FLOTATION/POROUS BALL/MEMBRANE INTEGRATED PROCESS

A flotation-porous ball-membrane integrated process was exploited to treat micro-polluted lake water with a kind of high algae，low turbidity and high organic substances． The experiment was conducted for more than 3 months，and the attention was focused on the performance of organic substances and algae removals by the integrated process． results showed that the integrated process removed organic substances and algae effectively． The average removal rate of turbidity，color， odor，COD，ammonia nitrogen and chlorophyll-a was 97. 8%，81. 7%，71. 4%，71. 9%，61. 4% and 94. 6%，respectively． Membrane had a significant effect on turbidity removal，and its average removal rate by this unit was 56. 7%． Flotation had a significant effect on removals of algae，color，and odor，with corresponding removal rates of 73. 5%，45. 3% and 50. 1%， respectively． Both flotation and porous balls presented good performance on COD and ammonia nitrogen removals． The average removal of COD and ammonia nitrogen by flotation was 30% and 29. 5%，respectively． While the average removal of COD and ammonia nitrogen by the porous balls was 30. 8% and 25. 2%，respectively．