Active water loss management has become one of the primary interests of the water utilities in the world. Due to efforts of the IWA Task Force in the last decade, traditional approach of water loss expression in percentage of system input values has been proven to be misleading in may cases, and new way of performance measuring and benchmarking is proposed. This paper presents the basic principles of this methodology and results of the first step in attempt to approach Serbian water utilities performance according to new standards. Pirot water supply system is used as a case study to estimate pressure reducing impact on technical performance indictor values before introducing active leakage control

Prototype of atmospheric pressure non-thermal corona plasma reactor, developed for degradation of organics in water, operates at significantly higher frequency than other reactors for that purpose, and without sparks. Its construction provides the umbrella shaped, sustained pulsating corona discharge, with defined discharge oscillations on a given pulse frequency above the water surface. Dye degradation rate decreases with the decrease of discharge current density. Plasmaformed H 2 O 2 is consumed in dye degradation. The energy yield of dye degradation is 2.45 g kWh −1 for 50 ppm solution, which is higher than in other publications for comparable experimental conditions.

Active water loss management has became one of the primary interest of the water utilities in the world. It can make significant saves and investments in new water resources capturing can be justified only if appropriate action is done to minimize loss from the water main. There is some level of unavoidable water loss from the water main. Traditional indicator of water loss, widely adopted in the world, was % of the system input value. It always sounds well to have water loss less than some prescribed value (for instance 10%). Due to efforts of IWA Task Force in the last decade, this approach has been proven to be misleading in may cases, and new way of performance measuring and benchmarking is proposed. This paper presents the basic principles of this methodology and the results of the first step in attempt to approach Serbian water mains to the new standards

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The results of the commercial indicator gas tube investigation, using the time delay measuring method are presented in this paper. This tube is usually used as an indicator of many electrical appliances. Time delay distributions for voltages from 75 V up to 100 V and relaxation times from 1 ms to 20 ms are presented. The time delay distributions for voltages U W > 75 V have Gaussian shape, and for U W = 75 V are multimodal. The multimodal time delay distributions indicate several different mechanisms which lead to breakdown. It is also shown that gas discharge tube has very small memory effect, which indicates fast response after the long (out of use) time, and consequently good characteristic for indicator tube. This characteristic of the used commercial indicators gas discharge tubes is consequence of gas tube geometry causing several processes which lead to breakdown under the same experimental conditions.