Issues with the restoration of nitrogen production molecular sieves
Thread Content
There is a nitrogen generation unit with a capacity of 1,000 cubic meters. Once, due to a malfunction in the pre-cooler, a small amount of water got into the system. Our staff disassembled the unit themselves; after doing so, they found that there wasn’t any serious problem. However, some of the molecular sieves were lost as a result, which meant there wasn’t enough of them left, and the unit can no longer operate properly. The issues are as follows: 1. What is the function of the alumina at the bottom of the molecular sieves, and can it be removed? 2. How to pack the molecular sieve? If it’s shaken, will it break? 3. Are there any other good suggestions? I earnestly request the expertise of all experts!
Let’s discuss it together; I plan to tidy it up again soon and share it with everyone at that time.
Let’s discuss it together; I plan to tidy it up again soon and share it with everyone at that time.
Is it cryogenic nitrogen production? The function of the activated alumina at the bottom is mainly to absorb moisture; compared to using only a single layer of molecular sieve, this approach allows for less use of molecular sieve, reduces the energy required for regeneration, and protects the molecular sieve. Do your adsorbers have manholes? If there are any unevenities, they can be leveled manually~~ It is also recommended to use cloth tubes that extend to the bottom, in order to reduce the rate of damage during filling~~ You can purchase molecular sieve and alumina directly for replacement or top-up purposes~~
The chiller is malfunctioning – was no action taken to reduce the load using molecular sieves?
It’s just the ordinary pressure swing adsorption technology; the equipment used in the Jiangsu area (the name of the company will not be mentioned for the sake of avoiding disclosure of trade secrets). Since this is the only method for nitrogen production using molecular sieves, and in order to keep the plant running, even when there are problems the load cannot be reduced; alternative methods are only resorted to when things really go wrong. There is a manhole at the top; we tried to level it manually, but it wasn’t filled properly, and it became loose as soon as it started operating. I don’t understand why. .
Is there a partition between alumina and molecular sieves? Additionally, add molecular sieve in small amounts multiple times, about 5–10 cm at a time, and level it off after each addition. The cloth tube is simply a long canvas tube into which the molecular sieve is poured; the bottom of this tube acts as a buffer, which helps to reduce the rate of damage to the molecular sieve~~
1. Aluminum oxide can be removed; it depends on the purification system used beforehand. Aluminum oxide is also used to prevent moisture absorption, and it’s possible to replace it. 2. What is the method of compressing the molecular sieve? Is it through cylinders, or is it compressed using large flanges and end caps? 3. Vibration compaction is necessary
You can remove all the molecular sieve, replace the alumina at the bottom with more of it to make up for the space taken up by the removed molecular sieve. The molecular sieve must be packed tightly; otherwise, it will become unusable after wearing out. Of course, with such a change, the gas production volume will be affected; the exact extent of the impact depends on the amount of loss of the molecular sieve.
The molecular sieve was compressed by using a large flange to press it down after filling it; at that time, there was concern that it might be damaged by vibrations, and it was not clear what kind of vibration would be appropriate, so only compression was applied without any vibration
Since it’s already installed, give it a try for now. Pay attention to whether there is any black dust coming from the exhaust area; if there is dust, stop using it immediately! It indicates that the molecular sieve has become powdered