Studies of the decontamination of the sewage from animal husbandry farms

Investigations revealed that under the conditions prevailing in the districts of Sofia and .pernik Ascaris suum and Trichocephalus suis eggs remained viable at the conventional storage of liquid manure on the large farms for about a year, and Fasciola hepatica and Paramphistomum sp. eggs--for 2 to 3 months. The methods of electrocoagulation and electroflotation could be employed with success in the cleansing and rendering harmless of the sewage waters after the preliminary treatment with calcium hydroxide. In terms of stabilizing the process, enhancing the cleansing effect and harmlessness, and lowering the use of electrical energy better results are obtainable with the use of pulsating current and constant current perdiodically changing its polarity.