MODIFIED ASPHALT PARTICLES AND METHOD OF THEIR PRODUCTION AND USE THEREOF Russian patent published in 2019 - IPC C08L95/00 C09K8/35 C09K8/516 C08K3/06 

FIELD: oil and gas industry.

SUBSTANCE: group of inventions can be used in drilling processes for oil and drilling fluids. Modified asphalt particles contain asphalt and modifier containing polymer and free sulfur. Content of elementary sulfur ranges from 10 to 40 wt% of total weight of modified asphalt particles, and content of polymer sulfur ranges from 30 to 70 wt% of total weight of elemental sulfur. To obtain asphalt particles, sulfur is heated to molten state, a preliminary stabilizer is added, inert gas is fed and maintained at pressure of 0.5 to 2 MPa for 10–100 minutes to obtain a liquid modifier. Asphalt is heated to fused condition in sealed conditions and inert gas is supplied at maintaining pressure from 0.2 to 1 MPa. Fluid modifier is brought into contact with fused asphalt, held for 10–60 minutes at weight ratio of sulfur to asphalt 1–4:6–9, preferably 1–3:3–7. Product is sprayed into a quenching liquid, which contains a stabilizer for quenching, selected from alcohols.

EFFECT: higher softening temperature of asphalt particles, lower plastic viscosity, high dynamic shear force, breaking strength of emulsion, high resistance to high temperature and system ability to carry out drilling mud.

19 cl, 4 tbl, 12 ex