Method for the anticorrosive treatment of waste plastics treating equipment

摘要

This invention relates to equipment for treating the aforesaid waste plastics directly with supercritical water, and an object thereof is to provide a method for the anticorrosive treatment of waste plastics treating equipment which makes it possible to use inexpensive stainless steel. Waste plastics treating equipment made of stainless steel is charged with a predetermined amount of an aqueous solution containing at least one alkali metal salt, and this aqueous solution is deaerated until its dissolved oxygen content is reduced to 0.5 mg/L or less. After the temperature and pressure of the equipment are raised until supercritical conditions are established, these temperature and pressure are maintained for a predetermined period of time.