METHOD OF PURIFYING SPENT PROPPANTS FROM OIL Russian patent published in 2020 - IPC C09K8/80 B01D21/26 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the field of oil industry and can be used in regeneration of oil-contaminated proppant after hydraulic fracturing of the formation for its further use as a propping agent. Proposed method comprises preparation of pulp by mixing proppants contaminated with oil with water medium. Above proppants are mixed with water at ratio of 1:4.0, respectively, frozen and brought to ice formation. Frozen proppant in the form of ice is milled and loaded into a container with a perforated bottom, which is placed above the settling tank. Ice is melted and proppant is washed out with hot water with steaming. Water is heated by submersible burner in reservoir, which is connected to vessel and to collector of contaminated water. Reservoir is divided into two parts by overflow partition wall to form settling tank and second part connected to heat exchanger. Container loaded with frozen proppant in the form of ice is supplied from above with a pipeline for supply of harmful volatile reagents to the gas holder after melting of ice. After complete cleaning of heated proppant from oil products to heated preset temperature and drying to preset temperature, hot proppant granules are unloaded into metal cone-shaped container. Inside cone-shaped container there is a pack of closed hollow circular rims with round holes towards proppant granules. Cone-shaped container has inclined bottom towards discharge branch pipe, which is shut off by shutter. Source of heat carrier includes gas supply and ignition plug. Combustion chamber has a reflector in the zone of maximum expansion of ignition of gas mixture in the form of a shell of a hollow truncated cone and connected to an internal wall of the combustion chamber. Combustion chamber is equipped with a shield in the form of a plate installed coaxially to the outlet hole of the cone. There is provision for control unit of hot heat flow and flue gases entering into vertical submersible burner into reservoir for accumulation of hot water and gas mixed products. Connection of control unit with unit of cold compressed flow supply to hollow rims fixed in cone-shaped reservoir for proppant cooling is provided.

EFFECT: increased efficiency of treatment ensuring possibility of using cleaned proppant for hydraulic fracturing of formation.

6 cl, 2 dwg