Hot-dip galvanizing exhaust air heat recovery and vacuum compensation
At Galv-Est AS's hot-dip galvanizing plant, the 45,000 m³/h of air extracted above the zinc bath created a strong vacuum and significant loss of thermal energy. We installed a ventilation unit with a plate heat exchanger featuring corrosion-resistant elements, which recovers heat from the galvanizing process and compensates for the vacuum. The solution enables efficient use of heat even at temperatures down to -25°C without additional heating.
Project challenge
During the hot-dip galvanising process, a significant vacuum was created in the plant, caused by the air extracted from above the zinc bath. The problem lay not only in the 45,000 m³/h airflow, but also in the fact that considerable heat energy was lost in the process. In addition, the corrosive effect of zinc vapours and dust had to be taken into account, which made finding a solution even more complex.
How we built the solution
Our solution was twofold: heat energy recovery and vacuum compensation. We selected a ventilation unit with high heat exchange efficiency and specially treated components capable of withstanding a corrosive environment. We also optimised the piping system, choosing a material suitable for ensuring long-term reliability.
- Ventilation unit with plate heat exchanger and corrosion-resistant, specially treated components
- Piping system made of stainless and acid-resistant material
- Airflow from above the zinc bath: 45,000 m³/h
- Efficient use of heat down to a temperature of -25°C without additional heating
Automation
The automation synchronises the operation of the zinc bath and the fans of our system. This ensures optimal compensation of air volumes according to actual demand.
Result
The solution enables the heat energy obtained from hot-dip galvanising to be efficiently reused for heating the workshop, reducing heat loss and the need for additional heating. At the same time, the vacuum created in the plant was compensated and long-term reliability in a corrosive environment was ensured.
Galerii
FAQ
Frequently asked questions
How large an airflow does this solution handle?
Does the equipment withstand the corrosive effect of zinc fumes and dust?
Down to what outside temperature can the heat energy be used without additional heating?
How does the system adapt to the actual production need?
What benefits does this solution provide to production?
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