Multi-stage membrane for N2 rejection
US10780392B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2018 |
| Grant date | Sep 22, 2020 |
| Priority date | — |
| Expiry date | Oct 17, 2038 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02C20/40
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Nitrogen is removed from biogas using a three-stage separation system based on gas separation membranes. The first stage separates a biomethane feed stream into a first permeate gas stream and a first retentate gas stream. The second stage separates the first permeate stream into a biomethane product gas and a first low quality biomethane gas stream. The third stage separates the first retentate into a second low quality biomethane gas stream and a waste gas. A biogas feed stream is pretreated to remove amounts of water, VOCs, and CO2 to yield a methane-enriched biogas stream. The methane-enriched biogas stream is compressed together with the first and second low quality biomethane gas streams to form the biomethane feed stream.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.