METHOD OF FEED WATER PREPARATION FOR LOW PRESSURE COIL STEAM GENERATORS Russian patent published in 2017 - IPC F22B27/00 F22D5/00 C02F5/00 

FIELD: chemistry.

SUBSTANCE: chemicals are added to the feed water, at that, two chemical reactant are added to this water: Aminat™CO-2 for final removal of oxygen from the feed water and Aminat™CO-3P to prevent scaling and adjust pH of the feed water, at that, the dose of the chemical reagent Aminat™CO 2 is calculated by the formula: D_CO-2=8×O₂+i, mg/dm3, where O₂ is oxygen content in the feed water in mg/dm³; i is the excess of reagent Aminat™CO-2, mg/dm³, which is in the range of 5-15 mg/dm³ for the feed water and in the range of 10-25 mg/dm³ for the boiler water, and the dose of the chemical reagent Aminat™CO-3P is calculated by the formula: D_CO-3P=186×(H_feed.w-H_res.)+6.7C_Fe, mg/dm³, where: H_feed.w. is feed water hardness, mg-Eq/dm³; H_res. is residual hardness, mg-Eq/dm³; C_Fe is iron content in the feed water in mg/dm³.

EFFECT: prevention of scale formation and corrosion processes on the heat transfer surfaces of low pressure coil steam generators.