UDC 628.32.66.081.63
DOI 10.35776/VST.2025.03.06
Shirkova T. N.
Reducing the flow of reverse osmosis concentrate in the process of solid waste landfill leachate treatment
Summary
Leachate of the municipal solid waste landfills is a major environmental hazard. Reverse osmosis technology is used for leachate treatment. The disadvantage of using reverse osmosis is generation of a large amount of concentrate because its disposal involves high costs. A technology is presented that provides for reducing concentrate flow to values that ensure the economic feasibility of its evaporation or removal by trucks. Reducing concentrate flow is achieved by changing the ratio of salt ion concentrations and organic substances. The separation of the concentrate solution is effected owing to the difference in the retention capacity of low-pressure nanofiltration membranes in relation to organic substances and monovalent salt ions. The separation of the concentrate solution provides for reducing not only its flow, but also the costs of its disposal, that is to process and reduce the volume of each solution separately at lower costs. A method for conducting experiments is presented, the results of the separation of the concentrate solution are given, as well as technical and economic calculations that allow comparing the effectiveness of the proposed approach with the traditional solution based on the use of high-pressure membranes.
Key words
filtrate , concentrate , reverse osmosis , reverse osmosis unit , nanofiltration , membrane selectivity , low-selectivity membranes , solid municipal waste landfill