Claims
- 1. A process for the drying of a compressed gas stream comprising a gas component and water, said process comprising contacting the compressed gas stream with an adsorbent to adsorb at least a portion of the water to produce a dry compressed gas stream, wherein said adsorbent comprises a shaped alumina particle having dispersed thereon a colloidal silica layer and wherein said alumina particle has a surface area between 250 and 550 m2/g.
- 2. The process of claim 1 wherein said alumina particle has a surface area between about 300 and 450 m2/g.
- 3. The process of claim 1 wherein said alumina particle has a surface area between about 300 and 400 m2/g.
- 4. The process of claim 1 wherein said alumina particle has a surface area between about 320 and 380 m2/g.
- 5. The process of claim 1 wherein the adsorbent has an attrition loss of less than 0.4 wt-%.
- 6. The process of claim 1 wherein the silica layer extends less than about 50 microns from the surface of the shaped particle towards the center of the particle.
- 7. The process of claim 1 wherein the adsorbent comprises a rehydration loss of less than about 5 wt-%.
- 8. The process of claim 1 wherein the shaped alumina particle is selected from the group consisting of spherical, an extrudate, a pill, a flake or a monolith.
- 9. The process of claim 1 wherein the gas component is selected from the group consisting of air, nitrogen, light hydrocarbons and mixtures thereof.
- 10. The process of claim 1 wherein the gas component comprises air.
- 11. The process of claim 1 further comprising periodically purging the selective adsorbent to desorb the water.
- 12. The process of claim 1 wherein the contacting of the compressed gas with the adsorbent takes place in a pressure swing adsorption process wherein the adsorbent is depressurized to an effective desorption pressure and purged to desorb the water.
- 13. An air brake dryer assembly having a refillable or replaceable cartridge containing shaped particles having a colloidal silica layer dispersed on the shaped alumina carrier, at least 60 percent of the colloidal silica being present in a band extending from the surface towards the center and having a width of less than about 50 microns and wherein said shaped alumina carrier has a surface area of about 250 to 550 m2/g.
- 14. The air brake dryer assembly of claim 13 wherein said shaped alumina carrier has a surface area of about 300 to 450 m2/g.
- 15. The air brake dryer assembly of claim 13 wherein said shaped alumina carrier has a surface area of about 300 to 400 m2/g.
- 16. The air brake dryer assembly of claim 13 wherein said shaped alumina carrier has a surface area of about 320 to 380 m2/g.
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a Continuation-In-Part of copending application Ser. No. 09/796,218 filed Feb. 28, 2001, the contents of which are hereby incorporated by reference in its entirety.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09796218 |
Feb 2001 |
US |
Child |
10307014 |
Nov 2002 |
US |