| Nowadays, the process that integration of urban and rural areas increasing rapidly.The population aggravating continuous which bring about plenty of influence andpressure on city environment. In recent years, the total emissions of wastewatersincreasely.In addition, Urban planning is also backward result in so many problems suchas that sewage concentration more and more highly, handle it became more difficulty. Atthe same time, areas of the sewage land are less than before. Therefore, it is imperativethat we should research novel technology that more efficiency, more quickly, coveredless space, easily conducted.This paper is to introduce the pressure aeration activated sludge-air flotationtechnology（PA-DAF）. This direction is namely coupling Dissolved air flotation（DAF）and high-pressurized biochemistry，meaning this technology can not only maximize thefunction of high-efficiency biochemistry but also lead the sludge quickly separate fromwater，which values its research and application in reality. This study includes the rapidprocessing performance. The result show that influence factors of the rise of suspendedmatter consist of bubble rise velocity, micro-bubbles size, the choice of flocculent. Theexperiment shows that most of the micro-bubbles particle diameter keeps from30um50um steady and no longer significantly reduce. By adjusting the reasonablebubble rise velocity to keep the bubble-particle flow up when mixed liquid suspendedsolids （MLSS） concentration is low. Hydraulic loading rate would have less influencewhen MLSS reach3000mg/L, and this is time for flocculent play a crucial role. Resultsshowed that Polyaluminium Chloride（PAC） could control actived sludge flow-up moreeffective compared with Polymerization ferric chloride（PFC） if it kept the density from30μm/L to50μm/L. Too high or low pressure of dissolved gas, air inflow, hydraulicretention time or initial pH value will made the removal efficiency had different levels ofreduced. The trial found the optimal control parameters by means of several trial factorsrespectively included that initial pH value=6.87.2,dissolve pressure0.4MPa, gas-liquidratio5:1,hydraulic retention time2h, volume loading1.22.2kg/m3d. At this time,COD will degraded to60mg/L within an hour, and NH4+-N will reduced to3mg/L after2hours biochemical reaction Process. |
