Hybrid low NO.sub.x process for destruction of bound nitrogen compounds
US5500194A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 4, 1994 |
| Grant date | Mar 19, 1996 |
| Priority date | — |
| Expiry date | May 4, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E20/34
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for treating an exhaust stream which includes high levels of noxious compounds containing chemically bound nitrogen, to produce an effluent stream that is extremely low in oxides of nitrogen and environmentally safe for discharge into the atmosphere. A source of oxygen and fuel is added to the exhaust stream to create a fuel-rich mixture, the quantity of fuel being sufficient to react with the available oxygen. The fuel-enriched stream is provided to a thermal reactor and reacted to provide a heated oxygen-depleted stream which includes quantities of by-product NO.sub.x, which stream is then cooled to 800.degree. to 1000.degree. F. Conversion oxygen is added to the cooled stream which is then passed over a first catalyst bed under overall reducing conditions, the quantity of conversion oxygen added being in stoichiometric excess of the amount of NO.sub.x in the stream, but less than the amount of combustibles, whereby the NO.sub.x is first oxidized to NO.sub.2, and then the NO.sub.2 is reduced by the excess combustibles. The stream is cooled to a temperature of about 450.degree. to 550.degree. F., and air is added to produce a further cooled stream at a temperature of abo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.