Method of high-concentration culture of nitrifying bacteria or denitrifying bacteria contained in activated sludge, culture promoter to be used in high-concentration culture method of nitrifying bacteria, and mehtod of weight loss treatmentof activated sludge

摘要

A method for incubation of nitrifying bacteria in a high concentration which are contained in a few amounts in activated sludge such as sewage sludge and excrement sludge and, in the said method, the activated sludge is subjected to nitrification and acclimation culture for about one to two months using a sludge-treated waste liquid such as dehydrated sludge filtrate and digested eluate (ammonia concentration: 100-300 mg/liter) under such a condition that the dissolved oxygen is 2-4 mg/liter, the pH is 7.5-8.5 of pH and the temperature is 25-35 DEG C and, at the same time, the pH which is apt to tend to an acid side during the acclimation culture process is constantly maintained within the pH range of 7.5-8.5 by addition of an incubation promoter comprising a mixture of sodium carbonate and sodium hydrogen carbonate (the molar ratio being 4-7:4-8) whereby the nitrifying bacteria contained in the sludge are subjected to an acclimation culture and accumulated. As a result, it is now possible to incubate the nitrifying bacteria in a large quantity and also in a high concentration.