Abstract: A chemical fluid for underground injection includes an inorganic substance, an antioxidant (e.g. ascorbic acid, gluconic acid, or a salt thereof, or ?-acetyl-?-butyrolactone, or bisulfite, or disulfite), and water. The inorganic substance may be a colloidal particle or a powder. The inorganic substance may be present in the chemical fluid in amounts of 0.001% by mass to 50% by mass based on the total mass of the chemical fluid for underground injection. The antioxidant may be present in the chemical fluid at a ratio of 0.0001 to 2 of the mass of the antioxidant to the mass of the inorganic substance. A surface of the inorganic substance may be coated with a silane compound. The chemical fluid may further include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, or a mixture thereof.

Abstract: A chemical fluid for underground injection includes an inorganic substance, an antioxidant (e.g. ascorbic acid, gluconic acid, or a salt thereof, or bisulfite, or disulfite), and water. The inorganic substance may be a colloidal particle or a powder. The inorganic substance may be present in the chemical fluid in amounts of 0.001% by mass to 50% by mass based on the total mass of the chemical fluid for underground injection. The antioxidant may be present in the chemical fluid at a ratio of 0.0001 to 2 of the mass of the antioxidant to the mass of the inorganic substance. A surface of the inorganic substance may be coated with a silane compound. The chemical fluid may further include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, or a mixture thereof.