Study of oil sludge, waste oil and other auxiliary substances influence on the methane hydrate dissociation

In this paper, classes of oil medium that ensure the methane hydrate self-preservation were identified. The following compounds and substances were studied: asphaltenes, resins, asphaltene-resin-paraffin deposits (ARPD), multiwall carbon nanotubes, meloxicam (C14H13N3O4S2), kinetic hydrate inhibitors (KHI) Luvicap 55W (copolymer of N-vinylcaprolactam and N-vinylpyrrolidone) and Luvicap EG (poly(N-vinylcaprolactam)), refined petroleum products (initial and waste) and 2,6-Di-tert-butyl-4-methylphenol (antioxidant fuel additive AO-29). Isolated oil components had practically no effect on the decomposition process of methane hydrate. It was observed, that the presence of surface-active additives in refined petroleum products leads to suppression of the investigated effect (self-preservation). It seems to be that in the case of used engine oils, the degree of manifestation of methane hydrate self-preservation effect depends on the duration of its operation (mileage). The obtained results can be the basis of recycling of ARPD and hazardous waste petroleum products in technologies for storage/transportation of natural gas.