Влияние ультразвукового излучения на время всплытия микропузырьков воздуха

Представлены результаты экспериментального исследования влияния ультразвукового излучения, генерируемого дисковым пьезокерамическим элементом ЦТС-19, на время всплытия микропузырьков, выделяемых из пересыщенного воздухом водного раствора. Показано, что под действием ультразвука происходит объединение пузырьков в комплексы, что увеличивает скорость их всплытия. Зависимость времени всплытия от частоты излучения носит сложный характер, применение ультразвука с частотой 160 кГц может снизить время всплытия с 39,9 до 13,5 с. Результаты работы могут быть использованы для увеличения производительности установок очистки сточных вод методом напорной флотации. The paper presents the results of an experimental study of the effect of ultrasonic radiation generated by a piezoelectric ceramic disk on the ascent time of microbubbles released from an aqueous solution saturated with air. It was shown that being irradiated by ultrasound, the bubbles combine into complexes, which increases the rate of their ascent. Dependency of the ascent time on the frequency of ultrasonic radiation is of a complex nature; however, the use of ultrasound with a frequency of 160 kHz can reduce the ascent time from 39.9 to 13.5 s. The results can be used to increase the productivity of wastewater treatment plants by pressure flotation.

Treatment of the Processing Wastewaters Containing Heavy Metals with the Method Based on Flotation

Treatment of the Processing Wastewaters Containing Heavy Metals with the Method Based on FlotationThe aim of the studies carried out at full technological scale was to indicate optimal systems of the two-stage precipitation and coagulation (PIX 113 - SAX 18, PAX XL1 - SAX 18, ALCAT 102 - lime milk and SAX 18 - PAX 16) in the process of eliminating heavy metals from wastewaters made in the processing plant producing sub-systems for domestic appliances. Precipitated pollutions were thickened by flocculation and separated by hydrogen peroxide enhanced pressure flotation. The experimental installation of maximal flow capacity: 10.0 m3/d consisted of: the storage-equalization tank, the processing pipe reactor, the pressure flotation station, and the reagent preparation and dosing station. Optimal doses of reagents and a flocculent as well as pressure and saturation time were defined for which maximal reductions in the load of heavy metals were achieved. The usefulness of hydrogen peroxide as a means of enhancing flotation was tested. The use of two-stage precipitation permitted the reduction in heavy metals (Cd, Cu, Cr, Ni, Sn, Zn), eg by applying ALCAT 102 - lime milk at the level exceeding 80%.