Techno-soil based on landfill leachate for layer-by-layer isolation of solid municipal waste landfills

The article describes the main negative aspects of storing municipal waste at landfills and substantiates the need for their layer-by-layer backfill with inert materials. The main materials used for layer-by-layer isolation were considered and the idea of using techno-soil based on landfill leachate stabilized with blast furnace slag with a mass ratio of components of 1: 1: 0.027 (filtrate, blast furnace slag and coagulant) was proposed. Invitro studies were conducted to substantiate the possibility of using techno-soil as a layer-by-layer insulating material: the chemical and phase composition of the techno-soil was determined; hazard class IV of the waste-based material was established; it was proven that the content of toxic substances in the aqueous extract from the material was lower than or equal to their content in the leachate of landfill; the integral oxidation index was measured and equal to 260 mgO2/l; the particle size of the material, its good compactibility and gas permeability to landfill gases, as well as water permeability to infiltrating atmospheric precipitation were established; the solubility of the material was less than 3 % by weight. Thus, the possibility of using techno-soil based on landfill leachate stabilized with blast furnace slag as an inert material in the operation of solid municipal waste landfills was proven.