What substances are contained in the PSA adsorption unit?
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May I ask, what substances are contained in a PSA unit? All I know are activated carbon, molecular sieves, and so on! ~~What are their functions?
It mainly consists of modified 13X molecular sieves, mordenite, coal-based activated carbon, fruit-shell-based activated carbon, and granular activated carbon fibers; customers use them for separating oxygen, carbon dioxide, etc
There are many types of adsorbents used in PSA units, and the choice is primarily based on the impurity components that need to be removed. Common ones include silica gel, molecular sieves, activated carbon, and activated alumina; there are also some special adsorbents available. Moreover, there are various types of molecular sieves.
Molecular sieve, ceramic ball, CO adsorbent, activated carbon, activated Al2O3
The PSA adsorption tower is filled from bottom to top with AI2O3 ceramic balls, activated carbon, molecular sieve, silica gel, and AI2O3 ceramic balls； The pore size of the adsorbent decreases from the lower layer to the upper layer; it first adsorbs the components in coke oven gas that are easiest to adsorb. As for the order of activity among these components, my memory is a bit fuzzy – I will let the original poster know tomorrow. :handshake
Different raw materials result in different adsorbents: 1) The C40 and HXBC-30D adsorbents are primarily used for adsorbing liquid heavy hydrocarbon components. 2) GL-H2 adsorbent: The GL-H2 adsorbent has a high capacity for adsorbing H2O; it is also easy to regenerate. Moreover, it possesses high strength and stability, making it suitable for use at the bottom of adsorption towers to remove moisture and protect the adsorbents located above it. 3) HXSI-02 adsorbent: The HXSI-02 adsorbent used in this device has inert chemical properties, and is non-toxic and non-corrosive. Installed in the middle and lower part of the adsorption tower to absorb moisture and C5+. 4) HXBC-15D adsorbent: The HXBC-15D adsorbent used in this device is a water-resistant, non-polar adsorbent that exhibits strong affinity for almost all organic compounds present in the feed gas. The specification used for this device is a Φ1.5 strip, which is installed in the middle of the adsorption tower and is primarily used to remove C2-C5 components. 5) Special adsorbent for HXBC-15C: The HXBC-15C adsorbent used in this device is filled in the upper part of the adsorption tower and is primarily used to remove C1-C2 components. 6) HX5A-49H adsorbent: The HX5A-49H adsorbent used in this device is a silicoaluminate with a cubic skeletal structure; it comes in the form of Φ2-3 spherical particles, and is non-toxic and non-corrosive. The HX5A-49H adsorbent not only has a large specific surface area but also a very uniform pore distribution. The HX5A-49H adsorbent is an excellent adsorbent with high adsorption capacity and excellent selectivity; it is placed at the top of the adsorption tower to remove methane, CO, and N2, thereby ensuring the purity of the final product.
The principle behind the material used in PSA adsorption units is to pass gas through an adsorbent with micropores; large-molecule gases get trapped within the adsorbent, or their flow rate is reduced, thereby separating the large and small molecule gases in the gas.
The materials filled in the PSA unit, in order from bottom to top within the adsorption tower, are: activated carbon (used to remove impurities such as sulfur dioxide and moisture from the gas), alumina or silica gel (primarily used to remove moisture from the gas), different types of molecular sieves (which are the key element for adsorption; molecular sieves are quite expensive), modified molecular sieves, and weights (used to compress the various adsorption layers inside the tower)
Fill from bottom to top with AI2O3 ceramic balls, activated carbon, molecular sieve, silica gel, and AI2O3 ceramic balls； The pore size of the adsorbent decreases from the lower layer to the upper layer; it can adsorb substances such as CO, nitrogen, and carbon dioxide from coke oven gas, but it cannot remove oxygen
The principle is similar, with slight adjustments for different uses
It varies depending on the adsorbent component; generally, there are AL2O3, activated carbon, and carbon molecular sieves, which are used to adsorb water, CO2, CO, and certain organic macromolecules respectively.