METHOD FOR OBTAINING MAGNESIUM OXIDE FROM NATURAL BRINES AND SIMULTANEOUSLY EXTRACTED WATERS OF OIL FIELDS Russian patent published in 2022 - IPC C01F5/02 

FIELD: oil industry.

SUBSTANCE: invention relates to the production of magnesium oxide from natural brines and simultaneously extracted reservoir waters of oil fields for the purpose of their subsequent injection into the layers of oil fields to maintain reservoir pressure. The brine and the produced reservoir waters are purified from oil and iron ions, after which they are treated with lime milk to form magnesium hydroxide. Carbonization of a suspension of magnesium hydroxide is carried out to obtain a solution of magnesium bicarbonate and a solid precipitate. The separated magnesium bicarbonate solution is heated to a boil to form magnesium carbonate, which is separated and calcined to produce magnesium oxide. Moreover, the pH value of the mentioned initial brines and waters is preliminarily determined, as well as their pH value after filtration of magnesium hydroxide. After the separation of magnesium hydroxide, the mentioned brines and waters are re-carbonized with carbon dioxide contained in the gases after calcination of magnesia with carbon dioxide, or with flue gases that are formed during fuel combustion. Carbonation is continued until the pH value of the brine and the associated produced reservoir waters reaches the pH value of the original natural brine. The resulting brine is filtered from the precipitated calcium carbonate precipitate and sent for injection into the layers of oil fields to maintain reservoir pressure.

EFFECT: method makes it possible to obtain magnesium oxide with a purity of at least 98% using lime of any quality on the basis of simultaneously extracted waters of oil fields, as well as natural brines with minimal emissions of carbon dioxide into the atmosphere.

1 cl, 2 tbl, 1 ex, 2 dwg