Evaporator pickling method

Abstract

The invention aims at providing an acid pickling method of an evaporator. The acid pickling method comprises the following steps that A, when maintained, the evaporator is subjected to water spray cooling through a spraying device; B, dilute sulfuric acid is injected into the evaporator, when the liquid level rises to 25% of the total liquid level, a circulating pump in the evaporator is started, acid liquor circulates in the evaporator, dilute sulfuric acid continues to be injected, dilute sulfuric acid injection is stopped till the liquid level rises to 50% of the total liquid level, circulation acid pickling of the evaporator continues to keep for 30 minutes, the circulating pump is stopped, and the acid liquor is discharged; and C, after the dilute sulfuric acid is discharged, tap water is injected, when the liquid level rises to 25% of the total liquid level, the circulating pump in the evaporator is started, acid liquor circulates in the evaporator, tap water continues to be injected till the liquid level rises to 30% of the total liquid level, circulation water washing of the evaporator continues to keep for 2 hours, the circulating pump is stopped, and liquid in the evaporator is discharged. The method overcomes the defect that the acid pickling time in the prior art is long, high efficiency and rapidness are achieved, and the time utilization rate is high.

Description

technical field [0001] The invention relates to the field of equipment cleaning, in particular to an evaporator pickling method. Background technique [0002] The pickling of the evaporator is an important work in the evaporation process, and it is an important means to ensure the heat transfer performance and stable production capacity of the evaporator. The existing pickling process is carried out during evaporation maintenance. The entire pickling time is generally 6 hours. If the time is too long, the cooperation with other processes will be reduced, resulting in a passive production organization and the inability to efficiently use stripping steam. Carry out production, resulting in a passive production situation. [0003] The original pickling operation steps are about 1 hour cooling process after the maintenance, 0.5 hour acid feeding process, 0.5 hour pickling process, 0.5 hour acid unloading time, 2 hours residual acid Washing process and 1.5 hours process switchi...