Regarding the jacket water of the two-stage converter

The flow in an overflow-type jacket is relatively steady, making it possibly easier to control. The liquid level is much easier to monitor visually.

The advantages of the overflow type over the boiling type for the jacket water in a two-stage converter are higher heat transfer efficiency and less scaling.

There are two types of water jackets: one is of the direct-flow type, with cold water circulating through it. The other type is the boiling type, where the water in the jacket remains at a constant pressure and boils; the amount of water added is limited to the amount that evaporates. The boiling water temperature seems high, which may not be favorable for cooling, but boiling water allows for rapid and uniform heat transfer, providing better protection. However, boiling water jackets require higher water quality, and steam condensate should be used. Cooling water should only be used temporarily in emergency situations, when the level of the water jacket fluid drops and there is no steam condensate. The water consumption in emergency situations is about three times that of normal times. Use desalinated water when there is no steam condensate while driving. Currently, all large ammonia plants use the boiling method, recycling the water from the secondary furnace, the gas transfer main pipes, and the jacket of the first waste heat exchanger as semi-deionized water or deionized water. If the original overflow heat transfer is replaced with boiling heat transfer, the normal jacket water flow rate can be reduced from 10–12 tons per hour to about 5 tons per hour. This post was last edited by mingyyan on 2009-3-1 15:47.]

In short, boiling is more economical, but it is less safe than the overflow method; our factory uses the overflow method and recovers the overflow water to send it to the water treatment plant. Easy to control, safe, and economical to recycle.

Our factory once switched to atmospheric pressure boiling, but we felt that boiling water posed certain safety risks, so we switched back to overflow mode

Reply to 1# epeter28: There is still some boiling-type two-stage jacket water available, but many systems have been converted to direct-flow type; the water that flows out can be directly returned to the deoxidation tank for reuse, thus avoiding water waste； The biggest drawback of the boiling type is: 1. Interface corrosion occurs at the area where the liquid surface evaporates in the two-stage furnace, and over time the jacket will get perforated. 2、Inadequate level monitoring can lead to drying out and accidents.

Agree with the person above; our factory’s situation is exactly as described

Many of the units in our factory are of the overflow type; they are simple and easy to operate, allow for the recycling of overflow water, and are safe and economical.