Experimental study on the performance of the dielectric barrier discharge technique in the treatment of simulated groundwater with high iron and manganese content

Abstract

Groundwater with high concentrations of iron and manganese is harmful to the human body and modern industries. Conventional methods of treating iron and manganese have the disadvantage of high costs and complex control processes. A dielectric barrier discharge (DBD) water treatment system was built to remove iron and manganese from groundwater in this paper. Single-factor experiments were used to analyze the effect of discharge power, initial iron and manganese concentrations, gas flow rate, liquid flow rate, initial pH, flocculant and capture agent process parameters on iron and manganese removal rates. It was found that Fe2+ removal rates can reach 97.31% and Mn2+ removal rates can reach 81.42% when the initial concentrations of Fe2+ and Mn2+ are 6 and 3 mg/L, respectively. The use of 10 mg/L NaHCO3 or 5 mg/L Ca(OH)2 increased the removal rate of Fe2+ to 99% but had no effect on the removal rate of Mn2+. It was found that the optimum treatment time for Mn2+ was different for different process parameters, mainly in the range of 9–15 min, which needs to be noted in future production applications. This work shows that DBD can effectively remove iron and manganese ions from groundwater and analyzes the removal mechanism. HIGHLIGHTS The removal of iron and manganese from groundwater was investigated.; The effect of individual factors on the removal of iron and manganese was analyzed.; DBD removed up to 97.31% of Fe2+.; DBD removed up to 81.42% of Mn2+.;

Keywords

• dielectric barrier discharge
• discharge power
• groundwater
• high concentrations of iron and manganese
• removal ratio