What is the difference between industrial acid washing and alkali washing?

The purpose of acid washing:

The main purpose of boiler acid washing is to remove iron oxide, copper scale, iron scale and other impurities in the evaporation heating surface of the boiler, and also to eliminate silicon dioxide and scale.

The purpose of alkali washing:

The purpose is to remove oil stains, oil residues and other protective agents in the boiler. Alkali washing refers to circulating the alkali-containing solution with the temperature of 95-100X in the condensate-water supply pipeline and the boiler body to remove oil stains, oil residues and other protective agents. The alkaline cleaning drugs used by the unit are alkaline phosphate solution, and different proportions of drugs are prepared according to the pollution situation of the cleaning circuit. After alkali washing, rinse with demineralized water, first rinse with large flow for about 30min, and then continue to rinse with demineralized water with smaller flow until there’s no fine particles and the pH value is less than 8.4.