Process for removal of nitrogen oxides and sulfur oxides from waste gases
US4442079A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1982 |
| Grant date | Apr 10, 1984 |
| Priority date | — |
| Expiry date | May 28, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02A50/20
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for removal of nitrogen oxides and sulfur oxides from waste gases by contacting the waste gases with a particulate material comprising an alkaline earth based absorbent for sulfur oxides. Essential features are a reaction temperature of 85.degree.-145.degree. C., a maximum value of 3 for the ratio of nitrogen oxides to sulfur oxides, and the presence of oxygen and moisture. In its preferred form the process comprises a spray drying-absorption reaction followed by particle separation in a bag house. Removal efficiency is improved by the presence of minor amounts of sodium sulfite together with the alkaline earth based absorbent. Also a special conveyance of material may be applied to improve efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.