Studies and experience of introducing the technology of ground water de-ironing and softening in the Moscow Area

Summary

The analysis of physical and chemical parameters of ground water quality from the wells of water intake facilities No. 4 and 5 in Zhukovskii town, Moscow Area, was carried out. Based on the results the priority pollutants – iron compounds, hardness salts, dissolved gases (carbon dioxide and hydrogen suphide) were identified. The technology of ground water conditioning with the use of bioreactors with jet vacuum ejection, subsequent filtration in moving bed filters and chemical water softening in a vortex reactor was substantiated. Under the conditions of an operating water intake field trials were carried out in a plant that comprised the models of bioreactor, degasifier, moving bed filter and vortex reactor. The process parameters of the main facilities operation that ensured the sustainable standard quality of the water after purification were specified. It was found that after bioreactor and filter charging water de-ironing alongside with the removal of dissolved gases was taking place. The efficiency of purification at the first stage is 88.9%, after filtration the concentration of iron in water does not exceed 0.3 mg/l. The required dosage (3.4 mg-eq/l) and concentration of sodium hydroxide solution (4%) that ensured the required level of preliminary de-ironed water softening were determined. The data on the implementation of the efficient technology of ground water conditioning at design stage and at the stage of reconstruction and upgrade of water pumping station No. 5 in Zhukovskii town are set.

Key words

filter , deferrization , aeration , bioreactor , ground water , degasification , softening , floating media , field trials , conditioning , jet vacuum ejection