Method and apparatus for treatment of exhaust streams
US5603215A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1995 |
| Grant date | Feb 18, 1997 |
| Priority date | — |
| Expiry date | Mar 23, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
In a system for treating an exhaust stream, such as the exhaust of an internal combustion engine (10), the exhaust is initially treated by a first catalytic converter (14) and its effluent is cooled in an indirect heat exchanger (18) with an extraneous coolant fluid, i.e., one other than recycled engine exhaust, before introducing the exhaust into a hydrocarbon trap (30) to adsorb hydrocarbons therefrom at least during a cold-start period of engine operation. Such cooling enables utilization of highly efficient adsorbent materials such as activated carbon which otherwise could not be used. Adsorbed hydrocarbons are desorbed from the hydrocarbon trap (30) as the engine exhaust heats up. The exhaust is passed from hydrocarbon trap (30) to a second catalytic converter (34) for oxidation of the hydrocarbons. The coolant fluid may be air and the heated air obtained from the heat exchanger (18) may be introduced into the oxidation catalytic converter (34) to heat the latter at least during cold-start operation and to supply additional oxygen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.