Features of Obtaining the Dispersed Gas Phase in Electroflotators

Abstract

The conditions for increasing the energy efficiency of the process of obtaining the dispersed gas phase in electroflotators by optimizing the parameters of the electrode unit operation are studied. As an efficiency criterion, the specific gas yield representing the volumetric flow rate of emitted gases per unit of current strength is taken. Studies on the model of electroflotation cell with a capacity of 5 dm³ were carried out. The influence on the specific gas yield of the ratio of densities of anodic and cathodic currents in the range of 52–2500 A/m² was analyzed. It is established that the basis of gas release is represented by the cathodic process of molecular hydrogen formation, while the anodic process of oxygen formation can be complicated by electrochemical reactions with anions included in the composition of wastewater. It is revealed that the highest specific gas yield, which is up to 95 % of the theoretically possible, is achieved at the ratio of active surfaces of anodes and cathodes equal to 2:1, respectively, in the range of anodic current density from 150 to 250 A/m² with cathodic current density from 300 to 500 A/m². It is concluded that the application of the research results allows increasing the energy efficiency of the process of gas dispersion generation, reducing the dimensions of the electrode block, optimizing the structural solutions in the design of electroflotators.