Vízügyi Közlemények, 1970 (52. évfolyam)

4. füzet - Rövidebb közlemények és beszámolók

(88) THE TREATMENT AND DISPOSAL OF SLUDGE By G. Öllös, Ph. П., Civ. Engr. (For the Hungarian text see pp. 425) Based on experience collected during a UN (WHO) sponsored study tour the typical practices applied for dewatering and disposing sludge resulting from the treatment of wastewaters are reviewed. In Chapter 3, starting from the fundamental idea of reducing the volume of sludge (Fig. 1 ), the more important methods of sludge treatment are described in the following sequence: a) Concentration methods, including mixing (Fig. 3) elutriation,flotation (Figs. 4, 5) and the Devoro process ( Figs. 6, 7). b

) Conditioning methods, including physical conditioning ( Figs. 8,9) and chemical conditioning. Chapter 4 is devoted to the different dewatering processes following concentration. The objective of these is to further reduce the water content of sludge. In this context natural dewatering, filtration, dynamic processes and combined processes are described in the following sequence: a) Of the natural dewatering processes the application of filter beds (Figs. 10, 11 ) and sludge ponds is critically reviewed. b) In connection with the filtration processes the potential applications of filter presses (Figs. 12 to 15) and the vacuum drum filter ( Figs. 16 to 19) are outlined, emphasising the welcome development due to the automation of filter presses. c) Of the dynamic processes the importance of centrifuges ( Fig. 20), and the experiences gained with the application of drum filters (Figs. 21 to 23) and vibrating screens (Fig. 24) are pointed out. d) Of the combined processes the Starcosa process, the Wegmann-Geiger process, the Lurgi process, the Passavant process and the Carbofloc process are described together with the operational experiences made with them. In Table III the different dewatering processes are compared on the basis of the water content of the dewatered sludge. Of the potential methods of sludge disposal the uses in agriculture (Figs. 29 to 31 ) and incineration, as well as the operational experiences thereof are reviewed in Chapter 5. Beyond the physical principles underlying the individual methods a description is given of the items of equipment used and the operational experiences gained with them. Starting from the present situation the expected trends of future development are outlined. PROBLEMS RELATED TO THE PRACTICAL APPLICATION OF SIMULATED HYDROGRAPHS OF PLAIN AREAS By G. Kienitz, Civ. Engr. (For the Hungarian text see pp. 457) In Chapter 1 the research work conducted at the Research Institute for Water Resources Development is described, in the course of which the method of hydrological systems analysis for simulating the runoff process in plain areas has been further improved. The related problems are also outlined. Relying on the physical-mathematical model described in earlier papers fl, 2] a program has been compiled for an electronic computer ( Fig. 1 ), using which the process under consideration can be simulated. This consists essentially in characterizing the plain catchment area and ist canal network with a group of parameters, while another group is used for characterizing the particular meteorological situation. The computer yields for the outflow section of the catchment, or for any arbitrary canal section the discharge hydro-