The primary signs of nitrogen generator carbon molecular sieve leakage include black smoke emitting from the venting management during the oxygen-rich exhaust process of the nitrogen generator, sometimes even with sieve particles ejected. The powdering of the molecular sieve and the damage to internal components of the equipment are the direct causes of powder leakage in the nitrogen generator.

1.1 Poor molecular sieve quality

Molecular sieve is an adsorbent that separates nitrogen by adsorbing oxygen, and its quality directly impacts the performance of nitrogen generators and the purity of the supplied gas. High-quality molecular sieve exhibits superior dust resistance, moisture-proof capabilities, strength, and adsorption compared to lower-quality versions. Poor-quality molecular sieve has a shorter lifespan and accelerates abrasion during operation.

1.2 Mole Sieve Filling Inaccurate

The nitrogen generator experiences low filling density of the molecular sieve due to the lack of a professional filling vibration device during the filling process. As the nitrogen generator operates, compressed air flows upwards through the bottom of the tank. After oxygen is adsorbed by the molecular sieve, nitrogen is transported to the downstream pipeline. Frequent impact from the air flow intensifies the wear on the internal molecular sieve, causing the material level to gradually decrease. When it reaches the lower limit of the top cylinder, the cylinder no longer exerts pressure or limits the operation of the molecular sieve, accelerating its pulverization. This leads to the powder passing through the filter, being exhausted along with the enriched oxygen.

1.3 Gas Source Pressure Level

Purified compressed air enters the bottom of the nitrogen generator tower, and the pressure of the gas source affects the operation of the nitrogen generator. Due to the high frequency of pressurization and depressurization in the PSA nitrogen equipment, the impact of pressurized gas on the molecular sieve causes wear on the carbon molecular sieve. Therefore, strict control must be exercised over the pressure and flow rate of the gas source. Excessive gas source pressure, at the moment the pneumatic valve opens, results in a significant impact on the molecular sieve, increasing the friction between the sieves. After the molecular sieve is fully adsorbed, the moment the intake pneumatic valve closes, the static friction force is relatively high as the sieve falls. Insufficient gas source pressure leads to a longer time for the molecular sieve to adsorb oxygen to saturation, which, in turn, extends the nitrogen generator's time to produce qualified nitrogen gas. This increases the friction time between the sieves, accelerating the sieving of the molecular sieve.

1.4 Air Valve Leaking

The nitrogen generator pipeline is equipped with pneumatic quick-open butterfly valve groups, pressure equalization valve groups, exhaust valve groups, and vent valve groups. Any valve group that does not close tightly and leaks may cause a gas flow in the other nitrogen generator that is temporarily out of service. The surge of the gas flow may also increase the static friction between the molecular sieve, exacerbating the pulverization of the sieve.

1.5 Inlet moisture and oil-gas mixture lead to failure

The nitrogen generator's front-end air intake is equipped with multi-stage filtration and drying facilities. The main components of this equipment include an air dryer, a high-efficiency filter, an alumina heating dryer, and a precision filter, forming an air source purification system.

Filter cores and alumina ceramic balls in the gas purification system must be replaced regularly. Damaged cores or delayed replacements can lead to water and oil contamination in the gas source, which are significant factors affecting the quality and service life of molecular sieve.

1.6 Cylinder Head Compression Not Tight Enough

Low gauge pressure, cylinder damage, and low material level in the nitrogen generator are all reasons for the top cylinder not being properly sealed. When the top cylinder is not sealed properly, it no longer restricts the molecular sieve, allowing more space for the gas flow to enter and increase the impact force between the molecular sieves, accelerating their degradation. In severe cases, this can affect the structural integrity of the equipment and exacerbate the damage to internal components.

July 1 - Filter and coconut pad破裂

Due to the prolonged impact of air flow and molecular sieve, the intermediate section of the filter and coconut pad has been damaged, causing the molecular sieve to fall to the bottom of the tank and leak out through the oxygen-rich exhaust pipe. If the damaged filter and coconut pad are not replaced promptly, it will lead to a vicious cycle, affecting the purity and flow of the product gas, and severely impacting the stability and safety of the equipment operation.