Why do tail chlorine pipes freeze?

Is the weather there too cold? I suggest you insulate the pipes.

I think your liquid chlorine level is too high, causing part of the liquid chlorine to escape into the tail chlorine pipe, where it vaporizes and absorbs heat, causing frost. Please check your liquid chlorine level.

The main reasons are as follows. The key is to analyze the cause based on your own process pipeline and find it in time, so as to avoid larger accidents. 1. The tail gas outlet valve of the gas-liquid separator of the liquid chlorine liquefier is opened too large, which is prone to this situation. ； 2. The valve from the gas-liquid separator of the liquid chlorine liquefier to the liquid chlorine storage tank or other reasons prevents liquid chlorine from entering the liquid chlorine storage tank smoothly. ；

The liquid chlorine lowering valve is clogged due to various reasons, and the liquid chlorine cannot flow. It overflows from the exhaust pipe into the system, which is more dangerous. :o

If the liquid chlorine is not being fed smoothly, the system will stop before the poster can post here: lol My analysis: Possibility 1. The unit used by the host unit uses a low-pressure method for liquefaction, and the temperature of the exhaust gas is relatively low. The opening of the exhaust valve is not too large, causing the temperature of the exhaust chlorine to drop below zero after throttling, and frost to form on the outer wall of the pipe. If this is possible, it doesn't matter. There is no need to keep warm or cold like the friend above said. Even if you do that, you will just not see the frost and the temperature will still be very low. ； Possibly 2. It is still caused by the throttling of the exhaust valve, and the liquefaction pressure of the chlorine gas is not too high, so it does not belong to the low-pressure method. However, due to the large pressure difference between the front and rear valves, the throttling phenomenon is more obvious. This kind of problem needs to be paid attention to. When the temperature is low in winter, the tail chlorine may be throttled and the temperature will drop to cause secondary liquefaction, causing subsequent system abnormalities. Might be wrong, just for reference.

It should be that liquid chlorine has entered the tail chlorine pipe. It is necessary to check the corresponding valves of the liquid chlorine system.

It's like this in winter. When it's cold, the separator opens wider and the temperature of the liquid chlorine is low, frost will form.

The moderator is unaware that this phenomenon often happened in our unit before, but there were no accidents. Sometimes steam is used, which is of course more dangerous. :handshake

1) The amount of synthetic exhaust gas is too large； 2) Liquid chlorine is not flowing smoothly into the tank ； 3) The liquefaction efficiency is too high and the purity of the exhaust gas is too low.

Pipe frosting is caused by the pipe medium temperature being below 0 degrees Celsius. Please analyze the reason why the exhaust gas temperature may decrease.

According to your description, it should be caused by the vaporization of liquefied exhaust gas. Insulation is not necessary. It would be better to add an exhaust gas buffer tank or distribution table.

　Owner, I would like to know a few things about your liquid chlorine plant.: 　1. Is your liquefier a coiled square box type or a tube type? 　2. Is the gas phase pipe of the liquid chlorine storage tank connected to the original chlorine or the tail chlorine? 　3. How big is the difference between the outlet of the liquid chlorine gas-liquid separator and the inlet of the liquid chlorine storage tank? 　4. What is the degree of subcooling of liquid chlorine? 　5. Is there a U-bend in the liquid chlorine discharge pipe of the liquid chlorine storage tank?

Vaporization absorbs heat, causing moisture in the air to form frost. The solution is to add a buffer tank.

No. 5, I have some doubts: Why set up U-bend? Is there any problem if I don’t set it up? Isn't the storage tank balanced with gas chlorine? :L

The purpose of setting up the U-bend is that the feed pipe forms a liquid seal in front of the storage tank to prevent the gas phase in the storage tank from passing upward through the liquid chlorine pipe, causing the liquid chlorine discharge to form a gas block. This post was last edited by hzggp on 2007-12-5 21:04 ]

Oh, according to what you said, there is no need to install a U-bend when installing an insertion pipe in the discharge pipe of the liquid chlorine storage tank.

It's obvious: It is caused by liquefaction of exhaust gas. The following data are given and you can check it yourself.: Temperature-20 -10 -5 0 5 10 Vapor pressure (A) atm 1.81 2.60 3.08 3.64 4.25 4.96

There is a problem when feeding into an empty tank. The feed pipe of the hydrochloric acid tank also has such a structure. The principle is the same. I estimate that the original poster's problem is that the material is not being discharged smoothly. The reason is that there is air resistance in the discharge pipe and it is not a physical blockage. It is recommended that the poster find out the cause as soon as possible, otherwise it will be a huge safety hazard. Generally, companies regard frost formation on the exhaust gas distribution platform as a safety incident to assess operating workers. Because the liquid chlorine liquefaction station and the exhaust gas usage station (hydrogen chloride or sodium hypochlorite station) are not well coordinated, the exhaust pipeline will be frosted. The problem in the owner's unit is probably a hardware problem of the device, not an operation problem of the employees. I'll post a post to let everyone know when it's resolved. So that relevant practitioners can learn from it. The safety of liquid chlorine is of paramount importance, and a large liquid chlorine leakage may force a chlor-alkali company to suspend production for rectification. I am by no means an alarmist.

We don’t know what the chlorine pressure is in the owner’s unit? If it is below 0.25MPa (gauge pressure), it means that liquefaction is not possible. To take a step back, it is liquefaction, and it is impossible to liquefy all the way to the hydrogen chloride synthesis station.

If it is the first reason, most companies will use raw chlorine to replenish it.； If it is the second reason, I have posted above to solve it ； I don't seem to understand the third reason.