The blast furnace of a steel metallurgy enterprise has molten iron inside at high temperatures, encased in a shell of the same metal material. To prevent the shell from melting, refractory bricks are placed adjacent to the molten iron, reducing heat transfer to the shell, increasing resistance, and expanding the temperature difference. Additionally, within the shell's metal interior, a circulating water system, known as the water-cooled wall, is added, with low-temperature circulating water flowing inside to carry away heat energy.
A decade ago, due to the un认可 of closed-loop cooling towers, open-loop cooling towers were used for the water-cooled walls to lower the temperature. After use, it was found that there were insurmountable defects.
Firstly, there's the issue of scaling. As the circulating water cools and降温 through evaporation in open towers and ponds, the scale ions do not脱离 and are continuously concentrated. Eventually, they exceed the saturation point and crystallize out in various parts of the system, particularly within the water-cooled walls. The scale on the inner walls thickens over time, severely affecting heat transfer and causing the blast furnace shell temperature to rise continuously. This can lead to the shell becoming soft or even cracking. To address this, the metallurgical system uses demineralized water and pure water as the circulating medium, but even the cleanest treatment will not reach 0%. As time goes on, the accumulated scale ions will still exceed the saturation concentration.
Next, issues with impurities, the tower and pool require sufficient contact and heat exchange with the air. Meanwhile, various impurities in the environment, after multiple layers of filtration, may still enter the recirculation system, causing blockages and severe consequences.
Again, issues with algae, in large ponds, ensure water buffering and increase safety coefficients; however, it also leads to an increase in still water, slow water flow, excessive algae growth, which is one of the causes of blockages.
Furthermore, water waste issues include: increased evaporation, frequent discharging of effluents, the飘逸 of open towers, and leaks in reservoirs, all contributing to increased operational costs.
Now, with the continuous maturation of the design and manufacturing technology of closed cooling towers, also known as evaporative air coolers, the standard high furnace cooling has been changed to evaporative air coolers, effectively eliminating the aforementioned issues and also reducing operation costs.
Its advantages include:
1. No Evaporation: Only temperature reduction, no evaporation or consumption; the circulating medium is completely isolated from the external air, with no contact at all. This eliminates the evaporation and consumption of the medium and the entry of impurities, ensuring the stability of the internal medium composition.
2. Non-scaling: Due to no evaporation, the concentration of scaling ions such as calcium, magnesium, and sulfate in the medium remains unchanged, hence scaling does not occur.
3. Easy Maintenance: All coils are fully visible, making maintenance convenient and repairs straightforward.
4. The equipment features four-sided air intake with low wind resistance, resulting in reduced fan power.
