Utilization of reverse osmosis concentrate to obtain commercial products of sodium sulfate and sodium chloride

Summary

The technology of evaporating concentrate of reverse osmosis process of Novoshakhtinsk wastewater with the purpose of obtaining commercial products of sodium sulfate and sodium chloride salts from is presented. The studies were conducted with model clear solutions for the development of process solutions to be implemented at the wastewater treatment facilities where wastewater with the salt content up to 3000 mg/dm³ was supplied. A process flow scheme with the methodology and description of the technological process of obtaining salts at the site of the Novoshakhtinsk wastewater treatment facilities is proposed. The results of several research stages are presented, the nuances of the technological process are described, the crystallization temperature from +2.9 to +3.5°C is selected, and the obtained final salt products are compared with the requirements of regulatory documents. The recommended process flow scheme eliminating all shortcomings will provide for improving the purification efficiency and reliability of the operation of the treatment facilities. The implementation of the proposed technology helps to reduce operating costs and allows solving an important environmental problem, i. e. waste transformation into a secondary material resource.

Key words

concentrate , reverse osmosis , salt-content , permeate , sodium chloride , sodium sulfate , salt obtaining , vacuum evaporation unit , crystallization , secondary material resource