Iwona Zawieja, Paweł Wolski
Kinetics of the changes taking place in the anaerobic sludge stabilization condition for the slow pace of biochemical decomposition of organic substances, affecting the length of time required to stop sludge digesters. The method of chemical-thermal treatment of sludge, increases the degree of disintegration of the particles, determining the acceleration of the hydrolysis process, the process of limiting the anaerobic stabilization. The use of excess sludge hybrid treatment prior to anaerobic stabilization process affects the intensification of subsequent phases of methane fermentation. The aim of the study was to determine the effect of chemical-thermal sludge modified in the following during the hydrolysis process increase the production of volatile fatty acids, and also obtained at this stage of the process, the digested degree of sludge. Excess sludge, which has been conditioned against anaerobic stabilization process was more susceptible to the generation of volatile fatty acids. Ability to transform organic matter is an important factor in the process of anaerobic stabilization. The effect of increase in susceptibility to biodegradation of excess sewage was evaluated on the basis of COD and VFA levels in sewage sludge that have been submitted to processes of disintegration of thermal, chemical, and chemical-thermal, relative to baseline. In the case of 8-daily methane fermentation of raw sewage over-the maximum rate of COD and VFA 1123 mg O2/dm3, respectively, and 771.43 mg CH3COOH/dm3 recorded on the 3rd day of the process. During the 8-daily anaerobic digestion of excess sewage disintegrated by hybrid method, i.e. with peracetic acid at a dose of 2.5 cm3 CH3COOOH/dm3 of sludge and then heat at 70°C for a period of 6 h maximum COD value was recorded in the age of initiation of the process – 5,616.67 mg O2/dm3, while the maximum value of the VFA – 3600 mg CH3COOH/dm3 on the 4th day of the process.
modyfikacja osadów; fermentacja metanowa
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