Adsorption bed structure and process
An adsorbent bed structure and process is disclosed for use in an adsorption based gas separation process. A conventional adsorbent bed in a gas separation process is replaced with a one or more modular compact adsorbent bed units which are connected to make an adsorbent bed structure. The modular design requires lower fabrication and maintenance costs; is easier to transport; and is easier to load with adsorbent material.
1. A modular compact adsorbent bed unit comprising:
a) two distal substantially parallel non-permeable and circular outer walls consisting of a first outer wall and a second outer wall;
b) two substantially parallel gas permeable and circular inner walls positioned within the outer walls consisting of a first inner wall and a second inner wall;
c) a circular external wall enclosing the peripheral edge of the inner and outer walls and forming a first compartment between the first outer wall and the first inner wall and also forming a second compartment between the second inner wall and the second outer wall,
d) a feed flow channel positioned at the approximate center of the inner and outer walls that allows for passing feed gas through the outer and inner walls and excludes the feed gas from being in flow communication with the first compartment, the feed flow channel being capable of flow communication that allows flow into a second modular compact adsorbent bed unit;
e) adsorbent material packed between the first and said the second inner walls and around an outer perimeter of the flow channel to form an adsorber bed;
f) and at least one outlet channel in communication with the first compartment that allows removal of permeate gas from the adsorber bed into a product gas manifold.
2. The adsorbent bed unit of claim 1 , wherein the product gas manifold is external to the external wall.
3. The adsorbent bed unit of claim 2 , wherein the adsorber bed has an inter-particle void fraction of less than 40%.
4. The adsorbent bed unit of claim 1 , wherein the outlet channel is located proximate to the non-permeable outer wall.
5. The adsorbent bed unit of claim 1 , wherein the static volume of all outlet channels in the modular bed assembly is less than 90 percent of the volume of the feed flow channel.
6. The adsorbent bed unit of claim 1 wherein the ratio of the diameter of one inner wall to the depth of the adsorbent bed is in a range of between 2 and 10.
7. An adsorbent bed structure comprised of one or more modular compact adsorbent bed units as described in claim 1 .