The plate heat exchanger has the characteristics of light weight, small floor space, low investment, high heat exchange efficiency, flexible assembly, easy to remove scale, and its role in heating work.It is increasingly highly valued by heating companies and gradually promoted to replace the original shell-and-tube heat exchangers.How to choose plate heat exchanger cleaning agent?
The cleaning agents currently used are pickling, which includes organic and inorganic acids. The main organic acids are: oxalic acid, formic acid and the like. The main inorganic acids are: hydrochloric acid, nitric acid and the like. According to the heat exchanger fouling and process, material and scale composition analysis:
(1) The heat exchanger has a small flow area and a complicated internal structure, and it is difficult to discharge if the cleaning liquid is precipitated.
(2) The material of the heat exchanger is nickel alloy, and hydrochloric acid is used as the cleaning liquid, which is easy to cause strong corrosion to the plate and shorten the service life of the heat exchanger.
Through repeated tests, it was found that the choice of formic acid as the cleaning solution is the best. Adding a buffer and a surfactant to the formic acid cleaning solution, the cleaning effect is better, and the corrosion of the cleaning liquid on the sheet can be reduced.Chemical tests on scale samples have shown that formic acid is effective in removing scale. Through the acid immersion test, it was found that formic acid can effectively remove the scale attached to the plate, and its corrosion effect on the heat exchanger plate is also small.