No abstract

Cavitation treatment of surface and natural waters is a method for their microbiological purification. The aim of the present paper was to investigate the possibilities for the disinfection of natural waters by cavitation treatment with a Ge USM Cleaner device. A full factorial experiment of type 22 was performed. The factors influencing the water purification process were studied. Based on the obtained experimental results, the activation energy, the thermal effect due to the disinfection of the water and the rate constant of the process were calculated. The thermodynamic parameters of the transition state -Gibbs energy, enthalpy and entropy were also calculated. The analysis of the experimental results proveеd the effectiveness of the method used for natural water treatment.

Hydrodynamic cavitation damages the apparatus by intensive cavitational erosion of the elements in a hydro system. Being acquainted with the mechanisms of effect, hydrodynamic cavitation can be used to intensify technological processes in different industrial areas. The aim of the present work is to investigate the possibilities using hydrodynamic cavitation for wastewater treatment from an urban treatment plant. To intensify the purifying process series of trials, at different levels of intensity of the electrical field in the zone of cavitation, were performed. Additionally presented, the electrical field assists in forcing the process of silver ions separation with the purpose of microbiological purification of the flowing water. Here we present the results of experimental studies conducted at various times and electrical fields intensity. These trials substantiate the idea of the microbiological purification of wastewaters via hydrodynamic cavitation and represent a huge range of opportunities for applying this method in various industrial fields. The basic criterion that supports our statement is the enormous drop of the microbe number by increasing the cavitation treatment time.

The energy efficiency of household refrigerating appliances was measured according to EN TSO15502. A Liebherr TKP 1650 built-in Domestic refrigerator is used to determine the influence of the capillary pipe geometry. The temperatures at the injection site of the refrigerant, the inlet and outlet of the evaporator receiver were measured. The obtained results show that there is no universal optimal geometry of the capillary pipe. There is no element of the refrigeration cycle whose change has no effect on the refrigerant flow rate passing through the capillary pipe. A change in the geometry of capillary pipe affects all other components of the refrigeration cycle and can greatly improve or impair the efficiency of the refrigerator. The potential for switching from one to two different geometries of the capillary pipe is approximately 8% improvement in energy consumption. Possible implementation should take into account the potential savings - 8% and the life cycle of the particular appliance (- 15 years). For the particular measured device, the consumption per year is about 75kWh, which should take into account that the device itself has a low volume and low energy consumption.