|
Biological fluidized bed granulation fluid bed granulation is efficient solid-liquid separation technology to the field of sewage treatment sewage treatment technology. Its characteristics are a processing unit through physical methods and the combination of biochemical methods, and complete chemical coagulation, sludge granulation, chemical and biological degradation, and other solid-liquid separation process. Experimental results show that the optimal operation conditions, biological fluidized bed granulation can effectively remove contaminants from water. In the biological fluid bed granulation wastewater treatment unit as a separate operation, a very important issue is the granular sludge stability and anti-jamming capability. In this paper, through laboratory testing of small devices investigated in a stable operating conditions, physical and chemical properties of granular sludge and cyclical changes in the fluidized bed influent loading conditions, the particle size of the granular sludge bed distribution, density variation of physical properties can, on this basis, for effective removal of particulate pollutants in sludge characteristics and the relationship between the granular sludge crushing and recovery performance were evaluated. Study the following conclusions: (a) work in a stable condition, the biological fluidized bed granulator to form a good granular sludge. The structure of dense granular sludge, floc effective density than conventional one order of magnitude. Broken due to particle growth and homeostasis and water layers, showing the height of the granular sludge bed size along a significantly reduced tendency. 10cm, 50cm, 90cm three highly granular sludge median particle size dso were 2.84mm, 2.22mm, 1.92mm. (2) in the biological fluid bed granulator series operating conditions, the two column particle breakage plays a major role in running high after 12 h of each particle size decreases, and the different heights of the particle size tends to be uniform of, but still maintain particle shape; switching level column, the particles play a major role in the growth, crushed particles to be restored, indicating that the particles of the fluidized bed has good dynamic stability and self-recovery. (3) in a number of switching cycle fluidized bed operating conditions, the effective density of granular sludge varies with the size of the trend is not obvious, the particle size - density relation in the double logarithmic plot is always in the same field, and much higher than the conventional density of floc, indicating that the formation of the granular sludge bed having a dense structure. (4) in the biological fluid bed granulator series operation under working conditions, a fluidized bed column height changes on the two particles in a fluidized bed sludge particle size column influential, but the impact of the law is not obvious. This is mainly because there are no two columns of coagulant and coagulant aids, which on the other hand fully explained in the biological fluidized bed granulation, coagulant and coagulant dosing for particle pollution The importance of the formation of sludge. (5) When the biological fluidized bed granulation in a steady operating state of total phosphorus in water, ammonia, COD can be effectively removed, the removal rate were 60%, 56.7%, 76.7%. (6) biological fluidized bed granulation removal of pollutants in water, fluidized bed height along the longitudinal gradually removed. Bottom of the column effluent just entering the fluidized bed, suddenly substantially reduce the concentration of pollutants, especially phosphorus in water and COD, which is mainly coagulants work. When the water gradually rising along the fluidized bed height, to further reduce pollutants in water, mainly granular sludge microorganisms in the work, the biodegradable organic microorganisms. Therefore, the biological removal of pollutants fluidized bed granulation is sedimentation, adsorption, biological degradation of the joint action.
|