Acid distributor clogged

There is no good solution; the only option is to stop the operation and deal with the acid separator. The procedure is as follows: after stopping the operation, turn on the fan to create suction, check that there is no sulfur dioxide present, then open the manhole, put on protective clothing, enter the tower, and use a thicker iron rod to ensure proper conductivity in each hole

Check whether the pressure difference across the catalyst layer has increased; powdered catalyst can also contribute to blockages.

There really isn’t much that can be done; the only option is to stop the machine for maintenance. It’s likely that the area is covered with broken porcelain rings. After the maintenance, it’s important to pay attention to regular upkeep, and it would be best to use something like a price filter. Also, is there less separation at the acid point?

I have never used a trough-type acid separator. I have a simple question: in a trough-type acid separator, the various acid distribution branches overflow from the upper middle part of the trough. For these branches to get blocked, it would have to be because the trough is filled with impurities, but where do these impurities come from? And how can they exist in the acid? The acid in this trough enters it after passing through an acid cooler (after the pump). With the dense layers present in the acid cooler, it’s impossible for any mechanical impurities to block the acid distribution pipes. So, in my opinion, the only possibility is that small ceramic rings have been blown into the acid separator trough. 　　　　　　　

This is actually a problem related to the structural design of the acid distributor; several cases have been encountered before. Logically, broken ceramic rings should not enter the downcomer from its top and cause blockages in it, as the density of these broken rings or bricks is greater than that of the acid.

Clean it up, then find the cause and make improvements

By the way, I haven’t asked the original poster yet whether this happens right from the start of system operation or only after it has been running for a while I still hope that the original poster will let everyone know once he has found out the truth, so that everyone can learn from it. This post was last edited by shen*rong2006 on 2009-3-27 at 18:33.]

The clogging of slot-type acid separators is relatively easy to clear, as the holes in their acid-dividing claws are large; however, ceramic ring fragments that are slightly larger than these claws can easily get stuck, making it difficult to deal with such situations. Furthermore, during maintenance, it is not sufficient to clean only the acid separator; it is also necessary to remove the acidic sludge that settles at the bottom of the circulation tank. This sludge contains many ceramic ring fragments, which are drawn up when the acid pump starts operating.

The system has been in operation for only three months; it features a tubular acid separation unit with anodic protection, and a PTFE throttle ring with an inner diameter of 11.5 mm is installed inside the acid separation claws. The system will be shut down for maintenance next week.

The root cause of the blockage is the broken porcelain rings; I don’t think there’s any doubt about that. I’ve seen similar situations many times on site. Not only in the acid separation units, but also in the acid cooling units, there are a large number of porcelain rings. As for where all these broken porcelain rings come from, I believe they are brought in during the acid circulation process. The fact that the acid discharge pipes in the trough-type acid separation units are positioned above the bottom of the acid separation troughs is intended to prevent porcelain ring fragments from entering the circulating acid. However, this final measure alone cannot stop porcelain rings from getting into the circulating acid. If there are a large number of porcelain rings in the previous processes, including the acid return process, then the issue of blockage is just a matter of time. Therefore, it is still necessary to strengthen the management of various processes; the necessary facilities and equipment, such as filters, must be installed in places like in front of pumps and at the acid outlet of the dry absorption tower.

A ring for F4? What is the acid feed rate and the diameter of the tower? What do you mean by “acid distribution claws”? In other words, what is the diameter of the acid drop tubes? Let me take a look for you

I don’t understand; I’m currently learning about sulfuric acid. I hope the original poster can find out the reason and share it, so that we can all gain some experience from it. I also thank everyone above for sharing so much experience

It’s necessary to stop the machine for maintenance: use a blower to remove the gas inside, check with ammonia solution to ensure there is no sulfur dioxide present, and then open a manhole so that technicians can go in and make the repairs……

Some time ago, I encountered a sulfuric acid production plant with a capacity of 1,800 MTPD where the liquid level in the first absorption tower rose to excessive levels. Upon checking both the drying tower and the second absorption tower, it was found that the downcomer of the acid separation device was severely blocked. It should be noted that the relationship between the blockage of the downcomer in the acid splitter and flooding is still under investigation, and the cause of flooding has not yet been determined.

Hehe, another tubular acid splitter with anode protection – the same problem! Before the major overhaul last year, it was found that the acid used for drying produced a lot of foam; reducing the amount of acid applied improved the situation, which led to the conclusion that the acid distribution holes were blocked. You don’t know until you conduct a thorough inspection; once you do, it’s shocking. Goodness, some of those areas are completely blocked. They claim to have a placement density of 43 units per square meter, but in our 18-square-meter tower cross-section, we found only about 40 areas that weren’t blocked. A large group of people was called in to work on each hole one by one; don’t think it was easy – many special tools as well as high-pressure water hoses were used, and eventually it was possible to make the acid distribution pipes that led vertically downward function properly. However, the acid distribution pipes on the sides of the acid distribution tank were difficult to make functional due to their curvature and the presence of throttle holes. This thing seems pretty risky to me. For this year’s major maintenance, it’s necessary to prepare in advance by lifting the acid distributor as a whole; only by blowing from the opposite side can the blockage be completely removed. The tubular acid splitter is an optimized evolution of both the trough-type acid splitter and the tubular acid splitter; it indeed has many advantages, but it tends to clog more easily than the tubular acid splitter and is harder to clean than the trough-type acid splitter, which significantly reduces its performance. Therefore, the manufacturers using it must remember to take appropriate preventive measures.

I’m not sure which type of acid separator is most widely used these days. Everyone can share information about how they use their own acid separators and what problems have arisen, so that we can discuss and learn from each other! ! !

Mengmoke’s Uniflo alloy acid splitter is also used in domestic plants, and no cases of extensive blockage in the downcomers have occurred so far.