According to the varied materials, the researching of biologic output of trickling filters

The system of trickling filter has been used widespreadly nowadays in biological water-purifition. In our country, the biologic units of the most city waste water purifition establisment is being made of trickling filter. In these establishments, usually crushed stone or the element, which is shaped specially and made of plastic, are being used. The flowing of filtered water on filling material influences on the biofilm, which is formed, and special feature of sedimentation. In this thesis, a general research has been done and necessary knowledges have been collected on trickling filters. Besides, according to the varied materials, the output of the trickling filters have been researched. At the end of the experimental workings, by using bazal tic pumice stone as filter material, it has been obtained a » graphic on the quantity-output. This graphic has been compared with other graphics, which have been obtained by the results of the experiments with the other filling materials. KEY WORDS : Trickling Filters, filling materials, bazaltic pumice stone, biologic output, biologic fi 1 tra t i on, economy.