| The process combined with methane generating pit,water-dropping aerating contact biofilm and combined flow wetlands was studied. The main contents were about the removal character and load of combined process, HRT and DO consumption of contact biofilm, affecting factors of water-dropping aerating, nitrogen and phosphorus removal of constructed wetlands, the mechanism of gypsum dephosphorization and the microbial morphology of contact biofilm and constructed wetlands.The conclusions of the study were:⑴When the influent loads were 0.27kgCODCr/ m3·d,11.65 gNH4+-N/ m3·d,12.60 gTN/ m3·d,3.42 gTP/ m3·d ,the removal ratio are upward 60%,80%,70%,70%.in addition, the system had the ability of enduring shock loading, the effluent TP concentration keeps below 0.3mg/L.⑵In the condition of inferior influent loading, the appropriate HRT of contact biofilm was 2.41h.⑶When the second type water-dropping baffle and the lower HRT were used, the better aerating effect was acquired. the DO concentration descended in the interval of 0-40cm,and the reaeration could not be ignored.⑷The high removal of nitrogen and phosphorus in constructed wetlands was maintained. nitrogen removal owed to nitrification and denitrification, the phosphorus removal owed to physical chemistrical of groundmass and reaction of gypsum.⑸In the condition of alkalescence, the reaction of gypsum and phosphate led the falling of pH within 40h. High phosphorus removal rate were gained in the condition of neutrality by the way of adding gypsum. The grain size of gypsum remarkable effect the TP removal.⑹The bacteria colonies,nitrobacteria and nitribacteria were at the high level of 1012cells/g,1011cells/g,1010 cells/g respectively, and the food chain was complex.⑺The subsurface flow and surface flow, the horizontal flow and vertical flow were skillfully hanged together in constructed wetland. Simultaneous, the high phosphorus removal ratio and resourcizing of waste were achieved making use of scrap material—gypsum and architectural garbage.
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