Brazed plate cooler is a very special plate cooler. Thi […]
Brazed plate cooler is a very special plate cooler. This type of plate cooler often presents some problems in the time of application. This is mainly due to the fact that there is no regular stop to raise, and the scale is one of them. Kind, then what are the technical points when stopping the cleaning?
1 Passivation treatment: After the acid washing is completed, the scale and metal oxide on the surface of the plate cooler are mostly dissolved and detached, and the new metal is exposed, which is highly corrosive. Therefore, after pickling, the heat exchanger plate Stop passivation disposal.
2 Pickling solution concentration: According to repeated experiments, the pickling solution is prepared according to the concentration of formic acid 81%, water 17%, buffer 1.2% and external active agent 0.8%. The cleaning effect is very good.
3 Pickling method and time: The pickling method is mainly stopped by static immersion and dynamic circulation. The pickling time was first static soaking for 2 hours, followed by dynamic cycling for about 3 hours. At the time of pickling, it is necessary to frequently sample and test the pickling concentration. When the difference between the two adjacent assays is less than 0.2%, the pickling reaction can be completed.
4 Pickling temperature: Increasing the pickling temperature is very beneficial to the descaling effect. If the temperature is too high, it can aggravate the corrosion of the acid cooler to the plate cooler plate. After repeated experiments, the pickling temperature is controlled at 60 degrees Celsius. it is good.