METHOD OF ECOLOGICALLY CLEAN PRESTARTING CHEMICAL CLEANING AND PASSIVATING OF SURFACES OF HEAT POWER-GENERATING EQUIPMENT Russian patent published in 2006 - IPC F28G9/00 B08B3/08 C23G5/36 

FIELD: heat power engineering.

SUBSTANCE: invention relates to prestarting chemical cleaning and passivating of equipment surfaces and it can be used for prestarting cleaning of heating surfaces of recovery boilers of steam-gas plants from inner deposits and cleaning of other boilers. Method includes washing of surfaces to be cleaned by survice water in open circuit, creating of at least one closed circuit including at least part of surface to be cleaned and provision of circulation of heated solution of chemical reagent in said closed circuit. Solution of reagent is prepared directly in each circuit by filling the circuit with desalinated or softened water with subsequent introduction of reagent. Water solution of mixture of volatile and film forming amines mixed with dispersing agent is used as reagent. Solution is heated to 70-350°C. Reagent is added at a rate of 5-25 g/sq.m to saturated surface of circuits revealed by appearance of concentration of reagent in solution within 25 mg/l. When content of ferrum compounds in circulating solution equals 10 mg/l. blowing through of circuits is started with introduction into circuits of make-up water and reagent. Cleaning is carried out for at least 24 h until concentration of ferrum compounds in circulating solution of reagent is reduced by 1/l, minimum.

EFFECT: simplified and reduced cost of cleaning, preventing of discharge of substances harmful to environment.

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