Accelerated technology for cleaning oil-contaminated soils

Abstract

Relevance. The uniqueness of the practical application of accelerated and environmentally safe technology for the reclamation of oil–polluted lands, which uses local mineral raw materials, a consortium of autochthonous hydrocarbon-oxidizing bacteria with multifunctional positive properties, effective phytomeliorants, is theoretically substantiated. Hydrocarbon pollution is eliminated directly at the spill site, and the rate ofreturn of disturbed soils to agricultural circulation is 3–4 times faster than traditional methods.Methods. Objects of research: mechanically activated bentopowder and nanobentonite, a consortium of hydrocarbon-oxidizing bacteria composed of three autochthonous strains, soil leached chernozem, spring wheat, Devonian oil. The concentration of oil pollution at the site was 6.4%. Bentopowder and nanobentonite were introduced in doses of 6.0 t/ha and 0.3 t/ha, respectively. Sampling was carried out with a sampler on the 0th, 15th, 30th, and 90th days.Results. The optimal doses of application of bento powder and nano bentonite to disturbed soil above the average pollution level (6.0 t/ha and 0.3 t/ha respectively) are recommended. After 15 days, the level of contamination is halved (to 51.1 g/kg and 40.8 g/kg with benton powder and nanobentonite respectively). Removal of the introduced mineral sorbent is not required, since it later becomes a source of mineral nutrition for autochthonous microorganisms-destructors and a soil improver. At the second innovative stage, a consortium formed from effective strains and adapted to specific conditions is used. The strains of the consortium fit into an ecological niche, adapt and begin to actively develop, utilizing oil and petroleum products. After a month, the level of contamination decreases to 19.2 g/kg and 9.2 g/kg with the addition of benton powder and nanobentonite respectively.