To the question of acidification of primary sedimentation sludge in tanks of sewage treatment stations in populated areas

In domestic waste water phosphorus occurs in the form of orthophosphates, polyphosphates and organic phosphorous compounds. For the phos-phorus removal from wastewater both biological and physical and chemical methods can be used. According to most experts the most environmentally safe and promising is biological method based on the activity of microorganisms of active sludge. The effectiveness of the method depends on the availability of the process of oxidationresistant organic matter. This can be achieved by conducting the acidification of raw sludge. The article presents the results of laboratory studies on the selection of optimal parameters of acidification of raw precipitation and sludge treatment facilities of the cities of Krasnoyarsk and Sosnovoborsk. We studied the effects of duration of staying of sediment in anaerobic conditions, its composition and humidity on the rate of formation of volatile fatty acids. On the basis of the conducted research the following conclusions can be made: to obtain oxidationresistant organics, necessary for intensification of the anaerobic stage of wastewater treatment, it is better to use raw sludge from primary sedimentation tanks; the higher the concentration of dry substance of sludge, the more intensive is the process of separation of vola-tile fatty acids; the time sufficient for acidification is 5-6 days.