Circular-hole block graphite heat exchanger
Thread Content
Our company uses circulating water to cool hydrochloric acid solutions in circular-hole block graphite heat exchangers. The heat exchange area of these heat exchangers is 50 square meters; they are vertical type heat exchangers. The diameter of the inlet and outlet pipes for the circulating water is DN40, while the diameter of the inlet and outlet pipes for the hydrochloric acid is DN150. It has been found that the heat exchange efficiency of these heat exchangers is not very good. I would like to ask those with more experience what could be the reasons for this poor heat exchange performance? Is it because the inlet for the cold medium in this heat exchanger is too small?
The temperature difference between the inlet and outlet of the cold medium is over fifty degrees, and the pressure difference for the cold medium is sufficient.
Can the circulating water and hydrochloric acid be replaced? Is such a large volume of hydrochloric acid needed for imports and exports?
A large temperature difference of the cold medium indicates that the flow rate is too low.
Is the temperature difference between the cold medium entering and exiting so large because the interface between water and hydrochloric acid is incorrect? It should be made of pure graphite; it is recommended to swap the media in the tube side and shell side @Wang Genrong
Can hydrochloric acid flow through the tube side of a graphite heat exchanger? Afraid of perforation
In typical block-hole graphite heat exchangers, hydrochloric acid flows through the tube side, while water flows through the shell side; the tube side is made of graphite pores, and the shell side consists of graphite pores along with a carbon steel outer layer
But on our side, the outlet of the hydrochloric acid pump is connected to a pipe with a diameter of 150 mm, which feeds directly into the shell-side inlet; there’s only a pipe with a diameter of 40 mm. If the pressure is too high, the heat exchanger won’t be able to withstand it
Moreover, if it passes directly through the shell side, it will corrode the outer carbon steel material
Take a good look at the heat exchanger drawings; be careful not to make mistakes that could cause corrosion of the casing. Also, is your heat exchanger made entirely of graphite?
Since hydrochloric acid is circulated to cool the hot gas, it is necessary to pass the hydrochloric acid through the heat exchanger