Study On The Characteristic And Experimental Reaserch Of Pipe-cone Shape Bio-bed In Treating Municipal Wastewater

According to the analysis of the application actuality and the problems of the filters used in the Biological Contact Oxidation Reactors, and base on the perfect shape filter, the pipe-cone shape filter which is innoxiously is presented. Through theoretical analysis and experimental test we can conclude as follows:(1) Because of the pipe-cone shape filter has unique framework and random packed the reactor, the pipe-cone shape filter bio-bed can greatly increase the settling area and the capability of sedimentation and entrapment. The calculation shows, the horizontal projection area of every m³ filter is equal to the settling area of the settling tank which the diameter is 6.3m. The sludge concentration can reach at 6.89kg/m³ by increasing the living area and quantity of microorganism.(2) Owing to the unique framework of the filter, different flow characterisrstics are created in local area inside and outside of the filter, Which is benefit to aeration, mixing and material transferring. The flow condition inside the filter is a bit turbulent, so it will be benefit to habitation and propagation of microorganism. Because the bubbles are continually cut, obstructed, stroked and smashed by the filters, it prolongs the residence time of the bubbles and increase the contact time and area between the bubbles and water in the reactor, so as to improve the oxygen transfer ratio. The material transfering can be improved by the alternant change of the micro-environment.(3) When use the pipe-cone shape fiter bio-bed to treat the simulated domestic wastewater, the removal rate of COD at HRT of 1h is 90%, and the COD of effluent is less than 50mg/l. When HRT is 6h, the removal rate of COD rearch the upper limit. When HRT is 4h the removal rate of NH₄⁺ -N is 79.1%, and the NH₄⁺ -N concentration...