Engine exhaust purification device
US8899024B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Sep 14, 2012 |
| Grant date | Dec 2, 2014 |
| Priority date | — |
| Expiry date | Mar 1, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An engine exhaust purification device comprises: a selective reduction type NOx catalyst; an oxidation catalyst disposed on an upstream side of the NOx catalyst; a reducing agent adding device which adds an NOx reducing agent to an exhaust gas of an engine; a control device which controls the reducing agent adding device; and an NO2 ratio calculation device which estimates an NO2 ratio of the exhaust gas flowing into the NOx catalyst. The NO2 ratio of the exhaust gas flowing into the NOx catalyst is calculated by a catalytic reaction model where the oxidation reaction of NO in the oxidation catalyst is numerically formulated, and the NO2 ratio is reflected to calculate an amount of ammonia adsorbed on the NOx catalyst by a catalytic reaction model where a chemical reaction concerned with the reduction of NOx in the NOx catalyst is numerically formulated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.