Increase in the efficiency of removal of iron ions from wastewater by aquatic plant ‘Lemna minor‘

Abstract

Wastewater from food production enterprises could have significant concentrations of total iron that must be decreased. Aquatic macrophytes, for example “Lemna genera”, have a high potential for iron ions removal, but kinetics and treatment parameters should be qualified. The aim of the work is to increase in the efficiency of removal of iron ions from wastewater in the process of biological wastewater treatment using ”Lemna minor” and to determine rational parameters of the treatment (biomass, process duration, hydraulic load). The kinetics of the removal of iron ions from the water was studied in the batch mode of a biological reactor operation under various biomass quantities. Verification of the obtained rational parameters of the process was carried out under continuous mode conditions. The results obtained from the kinetics of the batch mode the bioreactor operation process indicate an increase in the degree of removal of ferrous ions from wastewater from 61.0% to 91.7% with an increase in the plant biomass concentration from 8 mg/L to 25 mg/L during the wastewater treatment process of 24 hours. The rational parameters of removal of iron ions from wastewater in the batch mode of the bioreactor operation are determined: biomass of duckweed is 25 mg/L; the treatment process duration is 8 hours; the hydraulic load is 0,126 L/(h•L). The purification effect was 89.8%.

Keywords

• wastewater
• waste
• duckweed
• iron ions
• purification
• biomass
• hydraulic loading