Abstract: The oxidation dryer in a PTA plant of certain petrochemical company has run for threeyears.In the production process,the inner buildup of the dryer＇s cylinder frequently occurs and the scaling is formed,resulting in feed opening blockage and short-term running.This not only affects the longterm operation,but also brings safety risks.This paper analyzes the causes for the scaling problems within the dryer and takes corresponding measures to reduce the number of alkaline wash,which saves the cost of maintenance and energy consumption and helps to achieve the goal of extending the dryer＇s cycle of operation.