Study on treatment of oil extraction wastewater by grounding electrode atomization corona discharge coupling flocculant

As one of the main by-products of oil exploitation, oil extraction wastewater is characterized by high organic matter concentration and poor biodegradability. These challenges have spurred the development of low-temperature plasma wastewater treatment technologies. Among them, the grounding electrode atomization corona discharge (GEANCD) technology enhances the discharge current compared to traditional corona discharge. However, a key issue remains the uneven liquid atomization, which significantly impairs pollutant degradation efficiency. In this experiment, the self-designed spiral-hole electrode was used as the discharge electrode of the reactor, and the atomization corona discharge method was used to improve the discharge current and atomization effect. Firstly, the optimal discharge characteristics and operating parameters of the reactor were determined by parameter optimization experiments. Then, under the optimal parameters, the influence of treatment time on the removal rate of pollutants was explored. Finally, the flocculant (polyacrylamide) was introduced for coupled treatment. Compared with the single process, the strengthening effect of the coupled flocculant process under different treatment time was evaluated.The final effluent achieved a BOD₅/COD ratio > 0.3, which, according to the Chinese standard Code for Design of Outdoor Wastewater Engineering, indicates that the wastewater has been transformed from a “recalcitrant treatment challenge” into a “high-quality feedstock” for biological treatment-a marked improvement over many conventional pretreatment methods.