초록 ▼

Biogas released from landfills and sewage treatment plants is freed of siloxane contaminants by passing the biogas through a bed containing activated alumina, which absorbs the siloxanes. When the activated alumina becomes saturated with siloxanes, the absorption capability of the activated alumina

Biogas released from landfills and sewage treatment plants is freed of siloxane contaminants by passing the biogas through a bed containing activated alumina, which absorbs the siloxanes. When the activated alumina becomes saturated with siloxanes, the absorption capability of the activated alumina can be recovered by passing a regeneration gas through the bed of activated alumina. A system containing two or more beds of activated alumina can use one bed to remove siloxanes from biogas while one or more of the other beds are being regenerated.

대표청구항 ▼

What is claimed is: 1. A purification process for removing siloxanes from a biogas, the process comprising obtaining from a landfill or sewage treatment plant a biogas comprising siloxanes; passing the biogas through a bed comprising activated alumina; adsorbing onto the activated alumina at least

What is claimed is: 1. A purification process for removing siloxanes from a biogas, the process comprising obtaining from a landfill or sewage treatment plant a biogas comprising siloxanes; passing the biogas through a bed comprising activated alumina; adsorbing onto the activated alumina at least a portion of the siloxanes in the biogas; and regenerating the activated alumina by removing from the activated alumina at least a portion of the siloxanes adsorbed on the activated alumina. 2. The process according to claim 1, wherein the regenerating comprises heating the activated alumina. 3. The process according to claim 1, wherein the regenerating comprising exposing the activated alumina to a vacuum. 4. The process according to claim 3, further comprising heating the activated alumina while the activated alumina is exposed to the vacuum. 5. The process according to claim 1, wherein the regenerating comprises passing a regeneration gas through the bed. 6. The process according to claim 5, further comprising heating the regeneration gas before passing the regeneration gas through the bed. 7. The process according to claim 5, wherein the regeneration gas comprises the biogas. 8. The process according to claim 5, wherein the regeneration gas is selected from the group consisting of air and nitrogen. 9. The process according to claim 1, wherein the bed containing activated alumina is a first bed; during the regenerating of the activated alumina in the first bed the biogas is passed through a second bed containing activated alumina; and the process further comprises adsorbing onto the activated alumina in the second bed at least a portion of the siloxanes in the biogas. 10. The process according to claim 9, further comprising regenerating the activated alumina in the second bed by removing from the activated alumina in the second bed at least a portion of the siloxanes adsorbed on the activated alumina in the second bed. 11. The process according to claim 1, wherein the bed further comprises silica. 12. The process according to claim 1, wherein the activated alumina is selected from the group consisting of powder, beads and pellets.