Activated sludge treatment plant

A typical overloaded conventional complete-mix activated sludge treatment plant (shown in Figure 27.11) has been described in Section 27.3.3. The same conventional treatment plant can be improved by the addition of a secondary flotation clarifier (shown in Figure 27.12). Some advantages of the improved activated sludge system are mathematically presented below. 

Many pilot-scale and full-scale trials involving the use of secondary flotation (Krofta Supracell) in activated sludge treatment plants were conducted by KEC and Lenox Institute of Water Technology (LIWT) (formerly Lenox Institute for Research). Only partial operational data are selected for presentation in this chapter. The readers are encouraged to contact the authors for details. In the illustration of each case history, the true names of the company and its resident engineer involved are omitted for the protection of the Company s privacy. 

Many pilot plant operations have been conducted by KEC through Krofta Apparatebau G.M.B.H., Germany, under direct supervision of Mrs Elisabeth Hurst-Gaul, Manager. The use of a Krofta Supracell DAF clarifier for secondary clarification in the activated sludge treatment plant has been concluded to be feasible. This chapter summarizes the results of her investigation. 

A conventional activated sludge treatment plant in Flouston, Texas, is heavily overloaded. KEC and the LIWT evaluated the flotation characteristics of MLSS in the Krofta Supracell... 

For an existing conventional activated sludge treatment plant having a fungi problem, installing a DAF clarifier between the existing aeration basin and the final sedimentation clarifier (shown in Figure 27.12) will be the remedy. 

More advanced water purification techniques, utilizing UV-irradiation, ozonization, or activated charcoal, may significantly improve the removal of these compounds, but these techniques are not broadly applied due to their high cost. Thus, current European activated sludge treatment plants, with a hydraulic residence time not greater than 14 h, can in most cases not completely eliminate all the estrogens and progestogens from the effluent [23]. 

Figure 8B shows the regression of the measured percent overall removal from activated sludge treatment plants only measured by Simonich et al. with... 

Leuenberger, C., Giger, W., Coney, R., Graydon, J.W., and Molnar-Kubica, E. Persistent chemicals in pulp mill effluents. Occurrence and behaviour in an activated sludge treatment plant. Water Res., 19(7) 885-894, 1985. 

The activated sludge process has been successfully employed for the treatment of a wide variety of pharmaceutical wastewaters. The American Cynamid Company operated an activated sludge treatment plant to treat wastewater generated from the manufacture of a large variety of... 

Ramamurthy, R., et al. (1996). Control strategies for activated sludge treatment plants. Pulp Paper Canada. 97, 11, 32-37. 

Input effluent, activated sludge treatment plant, water + particles 1490 pg/1 1740 pg/1 na Sinkkonen et al. (1994) [16]... 

Fig. 6a d. Total ion GC/MS chromatograms with the exact value of (M+2)+ ion of TriCDTs from three pulp mill effluents a input to activated sludge treatment plant b discharge to sea c alkaline effluent from hardwood kraft d the chlorination mixture of dibenzothiophene. From [16]... 

Expert System for Diagnosis of Wastewater Treatment Plants Assists operators to diagnose faults in conventional activated sludge treatment plant (development) PC-Plus Micro G.G. Patry/McMaster Univ. 23... 

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