On The Bioflocculation-regeneration System And Its Characteristic Parameters

Based on the mechanism of the process to remove contaminants ,bioflocculation-regeneration was developed, which can easily remove pollutants from urban sewage under the condition of reducing infrastructure investment and operating costs. It has high application value to build urban sewage treatment plants in underdeveloped areas in China. The structure of the bioflocculation-regeneration system , the reactor structure and partial influencing factors including the reflux ratio and the hydraulic retention time are studied in China and abroad. But its process principle is not clearly understood and short of relevant researches, which make the study results lack of adequate generality. This paper studied the main factors of the process and determined the correlative parameters with analysis on their principles by systemic experiments.The cultivation of activated sludge adopted the method of simultaneous cultivation and domestication. The removal rates of COD, PO43--P and NH3-N increased as well as the sludge concentration during the cultivation period. A week later, the equipment worked stably. The sludge concentration of flocculator reached to 1 800 mg/L and 4 500 mg/L in the regenerated reactor accompanied with stable removal rate of organic compounds. Meanwhile, adsorption property and settling performance of sludge gradually improved.Through the research of bioflocculation-regeneration process, the values of aeration flux, recycle ratio, aeration time, flocculating time and SRT were 70L/min, 50%, 2h, 30min, which were the best running conditions.In bioflocculation-regeneration process, due to high sludge yield, the yield coefficient for heterotrophic bacteria is an important parameter. Not only affected the calculation of Sludge yield and oxygen demand, but also affected components of water and the calculation of kinetic parameters. There are many parameters that characterized this process's characteristics. It contains, readily biodegradable substrate(SS),slowly biodegradable substrate(Xs),Inert suspended organic matter (XI), Inert suspended dissolve substrate(SI).In this paper every parameter were researched. The result indicated the yield coefficient for heterotrophic is 0.71 g [COD]/g [COD]. The result is higher than experience. By Intermittent trials of biological flocculation, sludge adsorption and regeneration were studied tn his paper .The sludge in the flocculation to be less than that in the regeneration in some aspect like the removal properties. Inactivation of activated sludge were compared and found that the adsorption of activated sludge were better.