Oxidation treatment of photographic waste waters could be achieved with the Fenton's reaction for easy and complete degradation of the less decomposing organic compounds. Effects of amounts of hydrogen peroxide and iron (II) ion, pH and reaction temperature, etc. were investigated on the oxidation reaction. Chemical oxygen demand (COD) values were used as an analysis parameter of total oxidation behavior and chemical kinetics. Experimental studies were made by mixing the photographic waste waters with aqueous hydrogen peroxide and iron sulfate (II) solutions in a glass batch reactor. Some portions of the reaction mixture were timely sampled and transferred into 3 N NaOH solution in order to stop the oxidation reaction. After precipitation of the iron hydroxide (III), COD values of the residual sample solutions were measured by the acidic permanaganate method. The oxidation reaction was completed for about 120min, and the removal of less decomposing organic compounds such as metol, phenidone, hydroquinone and benzyl alcohol in the photographic waste waters was found more than 97%. The Fenton's oxidation reaction was proceeded when the reaction temperature became higher. The decomposition rate of COD substances showed the first order reaction of COD value, and activation energy obtained in the present work was 43.6 kJ·mol^-1. As the results, various actual photographic waste waters could effectively be treated with the Fenton's oxidation reaction.

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The objectives of work are to observe quantitatively the predator-prey relationship between Trochilioides recta and filamentous bacteria, and to discuss a new bulking control by using mass culture of chiliated protozoa.
T. recta was predaceous to Type 021N and Beggiatoa sp. from the end of the filament or the middle of it. In case of Type 021N, T. recta excreted the tubular material after taking bacterial cells. The predatory rate for Beggiatoa sp.is 7 times that for Type 021N. In addition, T. recta was predacious to short filamentous bacteria which grew in an anaerobic sewage.
It can be said from these results that T. recta is euryphagic as long as filamentous bacteria are given as food.

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[in Japanese]

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[in Japanese]

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