METHOD OF CLEANING INNER HEATING SURFACES OF HEAT-POWER ENGINEERING EQUIPMENT OF FERROUS OXIDES Russian patent published in 1995 - IPC

FIELD: heat-power engineering. SUBSTANCE: heating surface is treated with hydrazine acid solution, after which it is treated by ammonium salt solution of ethylenediaminetetraacetis acid. Then washing solution is subjected to alkaline neutralization and water and steam-oxygen treatment are performed in succession. Use is made of steam of heat-power engineering equipment. Temperature is raised at each stage of treatment. Supply of solution at each stage of treatment is regulated depending on pH of washing solution. EFFECT: enhanced reliability. 1 dwg, 1 tbl