Internal combustion engine with SCR and integrated ammonia production
AssigneeCollier Technologies, Inc.
InventorD. Neal Mulligan
Life of this patent
Estimating the term…
Abstract
NOx emissions from an internal combustion engine fueled by a gaseous hydrocarbon fuel can be reduced by catalytically producing a hydrogen and carbon monoxide fuel gas stream from the gaseous hydrocarbon fuel and a portion of the hot exhaust gas from the internal combustion engine. Furthermore, ammonia is also produced catalytically by reacting a portion of the hydrogen produced with ambient nitrogen present in the exhaust gas. The ammonia produced is used in connection with a selective catalytic reduction reactor to treat the remaining hot exhaust gas produced from the internal combustion engine, resulting in a treated exhaust gas stream having near-zero NOx emissions.
Claims20
An emission control system for use with a lean burn internal combustion engine of the type receiving a source of fuel and producing a hot exhaust gas stream containing water vapor, nitrogen, NOx, and oxygen, the emission control system comprising:
- a first reactor adapted to receive a first portion of the hot exhaust gas stream and a fuel gas to produce an intermediate exhaust stream containing hydrogen and ammonia;
- a separator adapted to separate the intermediate exhaust stream to a hydrogen-rich stream and an ammonia-rich stream;
- a conduit adapted to recycle the hydrogen-rich stream to the internal combustion engine as at least a portion of the source of fuel;
- and
- a selective catalytic reduction reactor adapted to treat a second portion of the exhaust gas stream with the ammonia-rich stream and produce a treated exhaust stream substantially free of NOx.
A method for reducing the emissions from a lean burn internal combustion engine of the type receiving a source of fuel and producing a hot exhaust gas stream containing water vapor, nitrogen, NOx, and oxygen the method comprising the steps of:
- a first reaction step for reacting a first portion of the hot exhaust gas stream with a source of fuel gas in a reactor to produce an intermediate exhaust stream containing hydrogen and ammonia;
- separating the reformed exhaust stream to a hydrogen-rich stream and an ammonia-rich stream;
- recycling the hydrogen-rich stream to the internal combustion engine as at least a portion of the source of fuel;
- and
- a second reaction step for reacting a second portion of the exhaust gas stream with the ammonia-rich stream to produce a treated exhaust stream substantially free of NOx.
Dependencies are inferred from the claim text.