Trial Study On The Performance And Kinetics Of Biological Aerated Filter

Biological Aerated Filter (BAF) is one kind of new developed biological sewage treatment on the late 1980s and early 1990s. Since 2001, The first BAF of China had been completed in Dalian Malan River sewage treatment plant. BAF technology received more and more attention in the field of sewage treatment process.The experimentation inspected the infection of hydraulic load, organic load, ammonic nitrogen load, the ratio of gas and water, the height of filling to removal efficiency of COD and ammonic nitrogen based on the self-confected water. The experimental result shows: the COD removal efficiency changes from 94.6% to 80% smoothly when the hydraulic load increases from 1.2 m~2 /(m~2 .h) to 2.8 m~3 /(m~2 .h). The ammonic nitrogen removal efficiency is over 72.1% when the hydraulic load in the range of 1.2-2.2m~3/(m~2.h). When the organic load changes from 2.41kgCOD/(m~3.d) to 5.4 kgCOD/(m~3.d), the COD removal efficiency is over 83.3%. When the ammonic nitrogen load is under 0.82kgNH3-N/(m~3.d), the ammonic nitrogen removal efficiency is over 75%. The great mass of COD removal is in the height range of 0-80cm. The great mass of ammonic nitrogen removal is concentrated in the height of 60-140cm. In single-factor experimental basis, the three parameters as the concentration of organic matter, the ratio of gas and water, hydraulic load was chosen to orthogonal tests. The orthogonal tests showed: the effectiveness of the factors on COD removal and ammonic nitrogen removal are characterized as follows: hydraulic load > the ratio of gas and water > the concentration of organic matter. Based on the ratio of gas and water 1:1, the experimentation achieved nitrate accumulation in the BAF reactor by the pH value controlling.The COD removal reaction in BAF accords with first order reaction. Its reaction kinetics can be simulated with first order exponential decay model: ρ_A =exp(0.0291-0.0426t)ρ_A0. The experimentation simulated the Submerged Biological filters model offered by GuXiaSheng. And the experimentation archives BAF kinetics model.