Chemical softening of the Don River water in a dynamic softening system – a unit with fluidized inert bed

Summary

Underground water sources with high levels of hardness salts are often used for drinking water supply. To provide for the potable water quality, water softening is required. The known softening methods result in significant amounts of liquid and solid waste, i. e. mineralized wastewater or sludge not subject to utilization. Chemical softening of drinking water in clarifiers is rarely used because of the difficulties in preparing chemicals, maintaining the required constant water temperature, and the complexity of the installations and their maintenance. Since the 1990s, the chemical softening technology in intensified reactors with contact media – such as vortex and fluidized bed reactors – has been developed and found widespread application in drinking water supply. These units are widely used in Europe and the USA being much easier to maintain than clarifiers. The capacity of these units reaches thousands of cubic meters per hour. Their main advantage is the elimination of liquid discharge and generation of solid waste that can be easily disposed of, with a virtually 100% clean water yield. In Russia, RPC Mediana-Filter JSC is actively developing this technology using DSS® (the proprietary dynamic softening system).

Key words

potable water , reagent treatment , suspended layer , pilot plant , water softening , contact media , fluidized bed , intensified reactor , liming , soda softening , river water purification , soda liming , DSS® dynamic softening system