Amine liquid regeneration device

This post was last edited by Clauspolunit on 2010-7-7 08:53 There are usually two types of reboilers at the bottom of the regeneration tower, one is the thermosyphon type and the other is the ax type. The thermosiphon reboiler usually has one inlet and one outlet. The liquid phase comes in and the vapor and liquid phases go out. What you are talking about is an ax reboiler, one in and two out. Thermosiphon reboilers were often used in the past, but due to corrosion and other problems, most now use axe-type reboilers. The reason why the ax structure has two outlets is that the lean amine liquid directly enters the bottom of the tower from one side of the reboiler baffle and is then sent out of the device.

Reply 2# Clauspolunit Can you be more detailed? Thanks!

Reply 3# The inlet of Shandong Huaxing thermosiphon reboiler is the liquid phase, and the outlet is the vapor-liquid two-phase, which circulates based on density difference. There is no lean amine liquid sent out from the thermosiphon reboiler, and the lean amine liquid is sent out from the bottom of the regeneration tower. The axe-type reboiler also enters the liquid phase (usually with a baffle), but usually has two outlets. The gas phase returns to the regeneration tower from the upper part of the reboiler, while the liquid phase is sent to each desulfurization device through the other side of the baffle and the bottom of the regeneration tower as a lean amine liquid.

“Thermosiphon reboilers were used more often in the past, but due to corrosion and other problems, are there many such problems? The equipment I'm about to install here seems to be of the thermosiphon type.

Is it a thermosiphon reboiler that is used in acidic water stripping where the liquid is fed in from the bottom and the gas phase exits from both ends of the upper side of the reboiler? ? ?

I can answer this question. The amine liquid flowing down from the regeneration tower cannot be said to be a lean liquid that meets the requirements.； two out: 1. The lean liquid is returned to the tower. This is the amine liquid heated in the reboiler. It should be said to be the real lean liquid. It all flows back to the bottom of the tower and is pumped out by a circulation pump. 2. The gas phase returns to the tower. Needless to say, the poster knows what this gas phase is, so I will not be wordy. I wonder if the poster understands what I mean?

Reply to 5# Due to the presence of vapor and liquid phases in the Shandong Huaxing thermosiphon reboiler, it will cause greater corrosion to the equipment itself (mostly based on experience during use). In addition, I just participated in an expert demonstration meeting on equipment selection and material anti-corrosion for sulfur recovery units and other desulfurization units some time ago. Most experts suggested that the amine regeneration reboiler should be of the ax type, and try not to choose the thermosiphon type.

The reboiler is also a type of heat exchanger. One inlet and two outlets are mainly used to obtain the highest possible heat exchange efficiency in the reboiler. The material flows in from the middle and flows out from both sides. The utilization rate of the heat exchange area is the highest, the vaporization is uniform, and it is closest to the countercurrent state.； On the other hand, setting up two outlets reduces the size of the outlet opening (after the lean liquid part is vaporized, the volume flow rate at the outlet will be much greater than the volume flow rate at the inlet), which also makes the equipment easy to design. At the same time, the symmetrical design of one inlet and two outlets makes it easy to arrange the inlet and outlet pipes. (You can imagine, if it is one inlet and one outlet, how should the heat exchanger be designed and how should the pipes be arranged? ) Finally, the liquid phase is connected to the bottom of the tower to prevent the reboiler from being unable to perform a normal siphon cycle due to abnormal conditions in the tower (the phenomenon is that the steam from the reboiler at the bottom of the tower cannot be added). Opening the valve causes the liquid phase at the bottom of the tower to flow into the reboiler and re-establish the siphon cycle. Under normal circumstances, this valve * It is closed, and the material entering the reboiler is the lean liquid from the last tray, so that the reboiler also plays the role of a tray.

There are usually two types of reboilers at the bottom of the regeneration tower, one is the thermosiphon type and the other is the self-pressure type. The thermosiphon reboiler usually has one inlet and one outlet. The liquid phase comes in and the vapor and liquid phases go out. What you are talking about is a self-pressure reboiler, with one inlet and two outlets. Thermosiphon reboilers were often used in the past. Due to corrosion and other problems, the corrosion problem of the reboiler tube bundle has not been well solved. Therefore, newly designed devices now generally adopt self-pressure reboiler structures. The reason why the reboiler structure has two outlets is because the lean amine liquid directly enters the bottom of the tower from one side of the reboiler baffle and is then sent out of the device. Because the inlet is higher than the outlet, the material leaving the reboiler relies on the pressure difference generated by the height difference between the inlet and outlet to ensure the normal flow of the material.